NPS- OC-94-006
NAVAL )gRRADUCE SCHOOLL Monterey, California
00N=z
OTICELECTF
THESIS
A NUMERICAL STUDY OFWIND FORCING EFFECTS ON THECALIFORNIA CURRENT SYSTEM
by
James R. Vann
September, 1994
Thesis Advisor: Mary L. Batteen
Approved for public release; distribution is unlimited.
Prepared for:Office of Naval Research800 N. Quincy StreetArlington, VA 22217-5000
r 7D
94-35200Ill!l|~fli,
NAVAL POSTGRADUATE SCHOOLMonterey, CA 93943
Rear Admiral Thomas A. MercerSuperintendent
Thi e• was prepared in conjunction with research sponmored in pan bythe Office of Naval Research, 800 N. Quincy Street, Arlington, VA 22217-5000.
Reproduction of all or pat of this qpox is authorized.
Relead by:
I a fResearch
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I1. AGENCY USE ONLY o4encb~mk) j2. REPORT DATE ~ 3. REPORT TYPE AND DATES COVERED41 1 WkMasier's Thesis
4. TITLE AND SUBTITLE A NUMIERICAL STUDY OF WIND FORCING S. FUNDING NUMBERSEFFECTS' ON THE CALIFORNIA CURRENT SYM~M (U)
6. AUTHOR(S) Vann, James R. a oo%*mom vi mar Besmn
7. PERFORMING ORGANIZATION NAME(S) AND ADDREZS(ES) 8.PERFORMINGNaval Pos4a'paua School ORGANIZATIONNmoodey CA 93943-S00 REPORT NUMBER
NPS-OC-4W-006
9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESI(ES) 10. IPONSORING/MONITORINGOffice of N"~v Resarcli AGENCY REPORT NUMBER300 N.- Qummy St.
Abgo.VA 22217-500
11- SUPPLEMENTARY N01S noe view expessed in this thesis ame ibm of the author azxd do not reflectthe officia policy or pmosido of the Departmnet of Defense or the U.S. Government,
12A. DISTRI3UTION/AVAILADUJLTY STATEMENT 12b. DISTRIBUTION CODEApproved for public releas; disvibution is unlimitied. j A
13. ABSTRACT Asiiaa20 used)
Ab ll-rsesaom, nf-lsvd praove eqmsbm corn model.a umeed w sinummdie s~oprnA of sanideelized, fle-booom.asee bosmndery oosamic regimse as a beft-hns lo climological averae (1950-939), individual yew, a~d .okqkl yew windkiting. 71e focus of 6o Nody Jsdie Ca~ofmsa Curmen Syism alongs di. amend regica, home 3S* N so 4730* N, off &c. Weetrom of Noedi America.
Two types of e;ipmn - w conduichud. Min first type fores die mode[ from 'rest wil dlimebological, 1981, and 1983Mondaly aid 10 examie dk. 2ero - pseof beesur. nuch sis awrrm, upwefling, meansders, eddie., and filaments. Tie
esodtype oomemus die forcing from die previous ye.ts loeainns di nasiatmace of dines. features.In die Em type of ea1. di f-Owl*lowing fesures ame observed: a polowad coastal sorface current nar die start and
end of sabb yewr, -m eyuirawwud nufacs anrea, a polaward undercuirrent, upwalling, meanders, and eddies. In die meooed typeof experemeews meanders and eddies were already presentat di. start of de exerimeeta. in addition to die features observedduring Owe fire type of eparsen, filamemsaama generated. The results support die hypodiess dia wind forcing is an inuortantmescumai fo die gemerstiom of may of die observed fetue in die CAlifonsia Current Systemi.
14. SUBJECT TERMS Primitive equation Model, California Current System, eddies, 15. NUMBER OFfilament, jets, undercurrent, wind forcing, curns PAGES 235
16. PRICE CODE17. SECURITY CLASSIFI- Is. SECURITY CLASSIFI- 19. SECURITY CLASSIFI- 20. LIMITATION OF
CATION OF REPORT CATION OF THIS PAGE CATION OF ABSTRACT ABSTRACTUnlUnclassi fncasfed Unclassified UL
NSN 7540401-230-550 Standard Form 298 (Rev. 2-89)Puawijie by ANSI Std. 239-18
ii
Approved for public release; distribution is unlimited.
A NUMERICAL STUDY OFWIND FORCING EFFECTS ON THE
CALIFORNIA CURRENT SYSTEM
by
James R. VannLieutenant, United States Navy
B.S., United States Naval Academy, 1984
Submitted in partial fulfillment
of the requirements for the degree of
MASTER OF SCIENCE IN
METEOROLOGY AND PHYSICAL OCEANOGRAPHY
from the
NAVAL POSTGRADUATE SCHOOLSeptember 1994
Author:__ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
James R. Vann
Approved by: A .
Mary L. Batteen, Thesis Advisor
ellL
Curtis A. Collins, Second Reader
Robert H. Bourke, Chairman,
Department of Oceanography
iv
ABSTRACT
A high-resolution, multi-level, primitive equation ocean model is used to
examine the response of an idealized, flat-bottom, eastern boundary oceanic
regime on a beta-plane to climatological average (1980-1989), individual year,
and multiple year wind forcing. The focus of this study is the California Current
System along the coastal region, from 350 N to 47.5* N, off the West Coast of
North America.
Two types of experiments are conducted. The first type forces the model
from rest with climatological, 1981, and 1983 monthly winds to examine the
generation phase of features such as currents, upwelling, meanders, eddies, and
filaments. The second type continues the forcing from the previous years to
examine the maintenance of these features.
In the first type of experiments, the following features are observed: a
poleward coastal surface current near the start and end of each year, an
equatorward surface current, a poleward undercurrent, upwelling, meanders, and
eddies. In the second type of experiments, meanders and eddies were already
present at the start of the experiment. In addition to the features observed during
the first type of experiment, filaments are generated. The results support the
hypothesis that wind forcing is an important mechanism for the generation of
many of the observed features in the California Current System.Aw.~ !.L t
v -'Aval a-x/orD~st Spd.aia
vi
TABLE OF CONTENTS
I. INTRODUCTION ................... 1
II. BACKGROUND ..... 3A. BRIEF DESCRIPTION OF REGION . . .. . ".. . . . 3B. CLIMATOLOGICAL WINDS..............................5C. EL NISO-SOUTHERN OSCILLATION. ........ . 7D. NUMERICAL MODEL STUDIES .................. .... 8
III. MODEL DESCRIPTION AND EXPERIMENTAL DESIGN . . . 19A. MODEL DESCRIPTION ......... ................ 19
1. Basic Model .......... ............... 192. Friction ... ......... ............... 193. Boundary Conditions .... . . . ............ 204. Domain and Resolution . . ................. 205. Finite Difference Scheme ................. 216. Method of Solution .... ............ .. 227. Initial Conditions ..... ............ .. 22
B. WIND AND ATMOSPHERIC FORCING ... ......... .. 22C. SPECIFIC EXPERIMENTAL DESIGN ... ......... .. 23D. ENERGY ANALYSIS TECHNIQUES ... .......... .. 24
IV. RESULTS OF EXPERIMENTS ._......... . .... 25A. EXPERIMENTS STARTED FROM REST .. ................. 25
1. Experiment 1 - Climatological Winds. . 252. Experiment 2 - 1981 Winds ...... ...... 293. Experiment 3-l1983Winds .. ................. 314. Summary of First Year Run Results ... .. 33
B. EXPERIMENTS SPUN UP FROM THE PREV.TOUS YEAR . 341. Experiment 4 - Climatological Winds . . .. 342. Experiment 5 - 1982 Winds ... ......... .. 363. Experiment 6 - 1984 Winds...... . . ... 384. Summary of Second Year Run Results . . . 405. Experiment 7 - Multiple Climatological Runs 416. Experiment 8 - Multiple Years (1981 - 1984) 427. Summary of Multiple Year Run Results . . . 44
V. SUMMARY AND RECO4MMENDATIONS ...... ............ .. 133A. SUMMARY................ ............ ..... 133B. COMPARISON WITH OBSERVATIONS DURING AN EL NI O
YEAR .............. ..................... 136C. NAVAL RELEVANCE .......... ................ 137D. RECOMMENDATIONS .......... ................ 138
vii
APPENDIX A. INSTABILITIES FOR EXPERIMENT 1 (CLIMO) . . 149
APPENDIX B. INSTABILITIES FOR EXPERIMENT 2 (1981) . . 157
APPENDIX C. INSTABILITIES FOR EXPERIMENT 3 (1983) . 167
APPENDIX D. INSTABILITIES FOR EXPERIMENT 4 (CLIMO II) 183
APPENDIX E. INSTABILITIES FOR EXPERIMENT 5 (1982) . . 193
APPENDIX F. INSTABILITIES FOR EXPERIMENT 6 (1984) . . 199
LIST OF REFERENCES ............. .................. 207
INITIAL DISTRIBUTION LIST .......... .............. 211
viii
LIST OF TABLES
4.1 SUMMARY OF INSTABILITIES FOR CLIMATOLOGICALYEAR (TOP), 1981 (CENTER), AND 1983 (BOTTOM). 46
4.2 SUMMARY OF EXPERIMENTS - FIRST YEAR ......... .. 474.3 SUMMARY OF INSTABILITIES FOR CLIMATOLOGICAL II
YEAR (TOP), 1982 (CENTER), AND 1984 (BOTTOM). 484.4 SUMMARY OF EXPERIMENTS - SECOND YEAR ........ .. 494.5 SUMMARY OF EXPERIMENTS - MULTIPLE YEARS ........ 505.1 COMPARISON OF OBSERVED AND MODEL RESULTS DURING
AN EL NINO YEAR (1983) ..... ............. 140
ix
x
LIST OF FIGUR=S
2.1 Generalized circulation schematic of theCalifornia Current System (CCS). .... . ... ... 11
2.2 Section of California Current System withschematized positions of jets and synoptic-scale eddies .......... ................ ... 12
2.3 Domain of model off the western coast of theUnited States of America ............ ....... . 13
2.4 Map of a portion of the west coast of NorthAmerica, showing the location of some of thepast studies in the CCS ........... ...... . . 14
2.5 Long-term mean atmospheric pressure at sealevel for (a) January and (b) July .... ...... 15
2.6 Long-term (1854-1972) mean wind stress(dynes cm"2 ) by one-degree squares, fromship reports .................... ....... ... 16
2.7 An illustration of the distributions of keyproperties involved in the teleconnectionprocess during a typical E1 Niflo-SouthernOscillation event ................ ..... ... 17
4.1 Mid-monthly averaged climatological (1980 -1989) ECMWF winds in m s-1: (a) January,(b) February, (c) March, (d) April, (e) May,(f) June, (g) July, (h) August, (i)September, (j) October, (k) November, and(1) December ........ .................. ... 51
4.1 (continued) ........ .................. ... 524.1 (continued). ....... . 534.2 Experiment 1: Surface meridio'nalcomponent
of velocity at day 30.. . . .. . ... 544.3 Experiment 1: Surface velocity'vectors at
day 90 ............. ... ......... 554.4 Experiment 1: Cross-section at y~704 *km
(41.250 N) of the meridional component ofvelocity at day 60 ........ ............ ... 56
4.5 Experiment 1: Cross-section at y-704 km(41.250 N) of the meridional component ofvelocity at day 90 ........ .............. ... 57
4.6 Experiment 1: Surface temperature at day120 ........................ ...... .... 58
4.7 Experiment 1: Surface velocity vectors atday 210. ......................... ......... 59
4.8 Experiment 1: Surface temprature at day210 .......................... ........... 60
4.9 Experiment 1: Surface temperature at day240 ........... ........................ 61
xi
4.10 Experiment 1: Surface velocity vectors atday 240 .......... ................... .. 62
4.11 Experiment 1: Surface temperature at day360 ........................... 63
4.12 Experiment 1: Surface velocity vectors atday 360 ........... .................... .. 64
4.13 Experiment 1: Cross-section of themeridional component of velocity at day360. . ................. ........ . ...... .. 65
4.14 Experiment 1: Total kinetic energy per unitmass time series for climatological (1980-1989) year over the entire domain . . .... . .. 66
4.15 Mid-monthly ECMWF winds for 1981 in m(a) January, (b) February, (c) March, (d)April, (e) May, (f) June, (g) July, (h)August, (i) September, (j) October, (k)November, and (1) December ............. .... 67
4.15 (continued) ........ .................. .. 684.15 (continued) ......... .................. .. 694.16 Experiment 2: Surface meridional component
of velocity at day 45 ........... ...... . . 704.17 Experiment 2: Surface velocity vectors at
day 90 ................. 714.18 Experiment 2: Cross-section at'y-704 km
(41.250 N) of the meridional component ofvelocity at day 90 .......... .......... ... 72
4.19 Experiment 2: Layer 5 (316 m) velocityvectors at day 210 ...... ............... ... 73
4.20 Experiment 2: Surface temperature at day120............ . ... 74
4.21 Experiment 2: Surface velocity vectors atday 210. ......... .... 75
4.22 Experiment 2: Surface temperatu~re at day210. . ..... .Surface -- . . .vectos .a . 76
4.23 Experiment 2: Surface velocity vectors atday 270. . ................................... 77
4.24 Experiment 2: Surface temperature at day270........................... . . ..... 78
4.25 Experiment 2: Surface temperature at day360 ........................ ........ ..... 79
4.26 Experiment 2: Cross-section at y-704 km(41.250 N) of the meridional component ofvelocity at day 360.. . . . _........ . ... 80
4.27 Experiment 2: Total kinetic energy per unitmass time series for 1981 over the entiredomain ............................ ... .... . 81
4.28 Mid-monthly ECMWF winds for 1983 in m(a) January, (b) February, (c) March, (d)April, (e) May, (f) June, (g) July, (h)August, (i) September, (j) October, (k)November, and (1) December .............. .... 82
xii
4.28 (continued) . . . . . . . . . . . . . . . . . . 834.28 (continued) .. .. . .. . .. . 844.29 Experiment 3: Surface velocity vectors at
day 30 ...... ... .............. ..... 854.30 Experiment 3: Surface velocity vectors at
day 120. ................. ................. 864.31 Experiment 3: Cross-section at y-704 km,
(41.250 N) of the meridional component ofvelocity at day 90 ..... ............... .... 87
4.32 Experiment 3: Surface temperature at day150........ ........... . . 88
4.33 Experiment 3: Surface velocity'vectors atday 150. ..... . .... 89
4.34 Experiment 3: Surface velocity'vector, atday 240. ..................... 90
4.35 Experiment 3: Surface temperature at day240 ...... . ........... ... 91
4.36 Experiment 3: Surface temperature at day360 .......... *............ . 92
4.37 Experiment 3: Cross-;ection it'y:704 km(41.250 N) of the meridional component ofvelocity at day 360. . .... 93
4.38a Experiment 3: Total kinetic energ.yper'unitmass time series for 1983 (days 1-306) overthe entire domain. ............ . ... 94
4.38b Experiment 3: Total kinetic energy per unitmass time series for 1983 (days 309-363)over the entire domain ..... ....... ... ... 95
4.39 Experiment 4: Surface velocity vectors atday 396 (yd 30) .......... ......... .. .... 96
4.40 Experiment 4: Surface temperature at day 396(yd 30). ... ....... 97
4.41 Experiment 4: Cross-section at'y:704 **m(41.250 N) of the meridional component ofvelocity at day 426 (yd 60) ..... ..... .. ... 98
4.42 Experiment 4: Surface temperature at day 546(yd 180) ..... ......... . 99
4.43 Experiment 4: Surface temperature at da'y606(yd 240) ....................... ..... ... 100
4.44 Experiment 4: Surface velocity vectors atday 456 (yd 9o) . ... ....._ 101
4.45 Experiment 4: Cross-section at Y'-704km(41.250 N) of the meridional component ofvelocity at day 666 (yd 300)... . .. .......... 102
4.46 Experiment 4: Surface temperature at day 696(yd 330) .... .. ............. 1034.47 Experiment 4: Surface temperature at day 726(yd 360)........................... . . ... 104
4.48 Experiment 4: Total kinetic energy per unitmass time series for Climo II over theentire domain ............ ................. 105
xiii
4.49 Kid-monthly IOU? winds for 1962 in a 3"1:
(a) January, (b) February, (c) March, (d)April, (e) May, (f) June, (9) July, (h)August, (i) September, (j) October, Wk)November, and (1) December .... ........... ... 106
4.49 (continued) .......... .................. .. 1074.49 (continued). .I.............................. 1084.50 Experiment 5: Surface velocity vectors at
day 396 (yd 30) ...... ................ ... 1094.51 Experiment 5: Surface meridional component
of velocity at day 426 (yd 60) ...... ........ 1104.52 Experiment 5: Cross-section at y-704 km
(41.25' N) of the meridional component ofvelocity at day 426 (yd 60) ...... ..... .111
4.53 Experiment 5: Surface velocity vectors atday 426 (yd 60) ........ ............... ... 112
4.54 Experiment 5: Surface temperature at day 516(yd 150) ........................ ....... 13
4.55 Experiment 5: Surface temperature at day 6;6(yd 240) ................................ * * _ 114
4.56 Experiment 5: Surface temperature at day 696(yd 330) .......... 115
4.57 Experiment 5: Totai kinetic ene'rgy perunitmass time series for 1982 over the entiredomain ............................. .... .. 116
4.58 Mid-monthly 306fF winds for 1984 in m s'1:(a) January, (b) February, (c) March, (d)April, (e) May, (f) June, (g) July, (h)August, (i) September, (j) October, (k)November, and (1) December ............... ... 117
4.58 (continued) .......... .................. ... 1184.58 (continued) .............. ............. ... 1194.59 Experiment 6: Surface velocity vectors at
day 396(yd 30) .............. ....... ... 1204.60 Experiment 6: Surface meridional component
of velocity at day 426 (yd 60) .......... 1214.61 Experiment 6: Cross-section at y-704 kJ
(41.250 N) of the meridional component ofvelocity at day 546 (yd 180) .... .......... .. 122
4.62 Experiment 6: Surface temperature at day 456(yd 90). . . . 123
4.63 Experiment 6: Surface- t _em-perature at'da•y576" ,(yd 210). . . . ............. ... 124
4.64 Experiment 6: temperature at day 666(yd 300).. . 125
4.65 Experiment 6: Totai kinetic energy per unitmass time series for 1984 over the entiredomain .......... 126
4.66 Experiment 7: Total kinetic energy*per'unit"mass time series for Climo III over theentire domain ......... ................. ... 127
xiv
4.67 Experiment 7: Total kinetic energy per unitmass time series for Climo IV over theentire domain ......... ................. ... 128
4.68 Experiment 7: Total kinetic energy per unitmass time series for Climo, Climo II, ClimoIII, and Climo IV over the entire domain . . 129
4.69 Experiment 8: Total kinetic energy per unitmass time series for 1983 over the entiredomain ........................... ............ 130
4.70 Experiment 8: Total kinetic energy per unitmass time series for 1984 over the entiredomain ............................ .... .. 131
4.71 Experiment 8: Total kinetic energy per unitmass time series for 1981, 1982, 1983, and1984 over the entire domain .. . . ... . . ...
5.1a Experiments 1-3: Total kinetic energy perunit mass time series for climatology (1980-1989), 1981, and 1983 over the entiredomain . .............. 141
5.1b Experiments 1-3: Mean kinetic energy perunit mass time series for climatology (1980-1989), 1981, and 1983 over the entiredomain ................ 142
5.1c Experiments 1-3: Eddy kinetic energy perunit mass time series for climatology (1980-1989), 1981, and 1983 over the entiredomain ...................... ............ .. 143
5.2a Experiments 4-6: Total kinetic energy perunit mass time series for Climo II, 1981,and 1983 over the entire domain ........... .. 144
5.2b Experiments 4-6: Mean kinetic energy perunit mass time series for Climo II, 1981,and 1983 over the entire domain ........... .. 145
5.2c Experiments 4-6: Eddy kinetic energy perunit mass time series for Climo II, 1981,and 1983 over the entire domain ........... .. 146
5.3 Experiment 3: Surface meridional componentof velocity at day 45 ..... ............. ... 147
A.1 Experiment 1: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for climatological (1980-1989)year, for model days 207 to 216 ........... .. 150
A.2 Experiment 1: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) forclimatological (1980-1989) year, for modeldays 207 to 216 ........ ........... 151
A.3 Experiment 1: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for climatological (1980-1989)year, for model days 228 to 231 ........... .. 152
xv
A.4 Experiment 1: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) forclimatological (1980-1989) year, for modeldays 228 to 231. .. .............. 153
A.5 Experiment 1: Energy transfers'of mean toeddy kinetic energy (i.e., barotropic energytransfer) for climatological (1980-1989)year, for model days 297 to 303 ........... ... 154
A.6 Experiment 1: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) forclimatological (1980-1989) year, for modeldays 297 to 303. .................. ... 155
B.1 Experiment 2: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1981, for model days 210 to222 ......... .... ..... 158
B.2 Experiment 2: Energytransfers of eddy
potential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1981, formodel days 210 to 222... ............. ...... 159
B.3 Experiment 2: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1981, for model days 240 to252 ............................... ....... 160
B.4 Experiment 2: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1981, formodel days 240 to 252 ........ ........ ... 161
B.5 Experiment 2: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1981, for model days 297 to303 ................. 162
B.6 Experiment 2: Energy trnfrso;ddy*potential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1981, formodel days 297 to 303 ............ ..... ... 163
B.7 Experiment 2: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1981, for model days 309 to333 ................ ..... 164
B.8 Experiment 2: Energy transfers'of eddy"potential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1981, formodel days 309 to 333 ........ .......... ... 165
C.1 Experiment 3: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1983, for model days 186 to192 .............. ...................... ... 168
xvi
C.2 Experiment 3: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1983, formodel days 186 to 192 .... ............. 169
C.3 Experiment 3: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1983, for model days 222 to234. . ........... ..... 170
C.4 Experiýent 3: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1983, formodel days 222 to 234. .............. 171
C.5 Experiment 3: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1983, for model days 249 to258. .......... 172
C.6 Experint 3: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1983, formodel days 249 to 258 .... ............. 173
C.7 Experiment 3: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1983, for model days 279 to288 ........................ 174
C.8 Experiment 3: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1983, formodel days 279 to 288 ................ 175
C.9 Experiment 3 Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1983, for model days 312 to315 .................... ......... . . 176
C.10 Experiment 3: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1983, formodel days 312 to 315 .... ............. 177
C.11 Experiment 3: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1983, for model days 324 to327 ........................... ........... 178
C.12 Experiment 3: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1983, formodel days 324 to 327. . ............ 179
C.13 Experiment 3: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1983, for model days 342 to348 .............. ...................... ... 180
xvii
C.14 Experiment 3: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1983, formodel days 342 to 348 ..... ............. ... 181
D.1 Experiment 4: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for Climo II, for model days 378to 408 (yd 12 - 42). ......................... 184
D.2 Experiment 4: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for Climo II,for model days 378 to 408 (yd 12 - 42) ........ 185
D.3 Experiment 4: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for Climo II, for model days 453to 465 (yd 87 - 99). ....... ..... 186
D.4 Experiment 4: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for Climo II,for model days 453 to 465 (yd 87 - 99) ........ 187
D.5 Experiment 4: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for Climo II, for model days 504to 516 (yd 138 - 150) .......... ........... 188
D.6 Experiment 4: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for Climo II,for model days 504 to 516 (yd 138 - 150) . ... 189
D.7 Experiment 4: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for Climo II, for model days 624to 636 (yd 258 - 270). .............. 190
D.8 Experiment 4: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for Climo II,for model days 624 to 636 (yd 258 - 270) . ... 191
E.1 Experiment 5: Energy transfers of mean toeddy kinetic energy (i.e-, barotropic energytransfer) for 1982, for model days 507 to516 (yd 141 - 150). . ............. 194E.2 Experiment 5: Energy'transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1982, formodel days 507 to 516 (yd 141 - 150) ........ .. 195
E.3 Experiment 5: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1982, for model days 525 to528 (yd 159 - 162) ........................... 196
xviii
3.4 Experiment 5: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1982, formodel days 525 to 528 (yd 159 - 162). ...... 197
F.1 Experiment 6: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1984, for model days 576 to591 (yd 210 - 225) ........ . .......... 200
F.2 Experiment 6: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1984, formodel days 576 to 591 (yd 210 - 225) ........ .. 201
F.3 Experiment 6: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1984, for model days 606 to624 (yd 240 - 258) .................. 202F.4 Experiment 6: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1984, formodel days 606 to 624 (yd 240 - 258). ..... 203
P.5 Experiment 6: Energy transfers of mean toeddy kinetic energy (i.e., barotropic energytransfer) for 1984, for model days 645 to657 (yd 279 - 291) ............ ..... 204P.6 Experiment 6: Energy transfers of eddypotential to eddy kinetic energy (i.e.,baroclinic energy transfer) for 1984, formodel days 645 to 657 (yd 279 - 291) ........ .. 205
xix
'cc
A C-------- -T
The author wants to thank Dr. Mary Batteen for her
guidance and patience during the work in performing this
investigation. Additional thanks to Mike Cook for his
endless assistance with UNIX, FORTRAN, and MATLAB
progranmTing, and to Pete Braccio for his invaluable
assistance with numerous model runs and visualization of the
results.
xxi
I. INTRODUCTION
The California Current System (CCS) is an eastern
boundary current (EBC) off the west coast of the United
States of America. A primitive equation numerical model
developed by Batteen et al. (1989) is used to simulate the
currents, eddies and filaments in the CCS. In this study
monthly winds from the European Centre for Medium-Range
Weather Forecasts (ECMWF) global data set from 1980 to 1989
(which include El Niflo events) are used to force the model.
The thesis is organized as follows: Chapter II
describes the region modeled, the El Nifto-Southern
Oscillation (ENSO), and some previous modeling work in this
region. The numerical model which was used here along with
the experimental setup are presented in Chapter III. The
results of the various model simulations are presented in
Chapter IV. Chapter V sunmarizes the work, discusses naval
relevance, and presents recommendations for future research.
Comparisons of model simulations with available observations
are shown in both Chapters IV and V. Six appendices follow
which contain the detailed results of the barotropic and
baroclinic instability analyses for the main experiments.
1
2
II. BACKGROUND
A. BRIEF DESCRIPTION OF REGION
The west coast of North America serves as an eastern
boundary for the circulation of water in the North Pacific
Ocean. The entire flow along the coast is referred to as
the CCS, which is a classical subtropical EBC system.
The CCS consists of three separate component flows, each
of which varies both spatially and seasonally (see Figure
2.1): an equatorward surface current, a poleward
undercurrent and a poleward surface current adjacent to the
coast (Tisch &t al., 1992). This latter current can be a
surface manifestaLion of the undercurrent or a separate
current.
The predominant flow is an equatorward surface flow
called the California Current (CC). The second basic flow
is the poleward undercurrent which has been called both the
California Undercurrent (CUC) (e.g., by Batteen = al.,
1989) and the California Counter Current (CCC) (e.g., by
Hickey, 1979). Thiq is a relatively weak subsurface flow
(around 5 cm a-1).
The third basic flow is the Inshore Current (IC), which
is known as the Davidson Current (DC) north of Pt.
Conception. This is also a relatively weak poleward flow
3
found at the surface and near the coast. There are other
ICs known as the Southern California Countercurrent (SCC) to
the south, and the Southern California Eddy (SCE) inshore of
the Channel Islands within the California Bight (Hickey,
1979), which are both equatorward of the model region (see
below) to be studied.
The CC is a broad, slow (-10 cm s-1) flow which can
extend offshore around 1000 km (Hickey, 1979). Superimposed
on this mean flow are highly energetic mesoscale eddies and
meandering jets which can have peak velocities near 80 cm
s-1 (Mooers and Robinson, 1984). Figure 2.2 depicts these
features.
A section of the CCS from 350 to 47.50 N and extending
12.5 degrees offshore from the coast will be the model study
area and is depicted in Figure 2.3. Major observational
programs which have sampled this region are quite numerous
and include: California Cooperative Oceanic Fisheries
Investigation (CalCOFI), Coastal Ocean Dynamics Experiment
(CODE) I and II, Large-Scale West Coast Shelf Experiment
(nicknamed SuperCODE), Coastal Upwelling Experiment (CUE) I
and II, Ocean Prediction Through Observation, Modeling and
Analysis program (OPTOMA), and Central California Coastal
Circulation Study (CCCS). Figure 2.4 depicts some of the
areas of observations.
4
B. CLIKATOLOGICAL WINDS
The North Pacific Subtropical High dominates the
atmospheric circulation off the west coast of the United
States of America, and varies in position and strength by
season (Huyer, 1983). In the winter (January) the high is
about 1020 mb and centered near 300 N, 1350 W (Figure 2.5a).
In the summer (July) the pressure increases to 1025 mb and
the center moves northward to 380 N, 1500 W (Figure 2.5b).
Over the continental west coast the typical pressure is 1020
mb in the winter, and 1015 mb during the summer, the latter
in response to a thermal low (of 1005 mb) in the central
valley of California (Huyer, 1983). This results in a
tighter pressure gradient against the west coast during the
summer. As this gradient tightens, stronger winds can
result.
Propagating atmospheric disturbances (Halliwell and
Allen, 1987), along with other atmospheric mesoscale
phenomena (Huyer, 1983), further complicate the wind pattern
on a daily, as well as on a seasonal basis along the coast.
The winds are also affected by coastal atmospheric boundary
layer processes within 100 to 200 km of the coast (Halliwell
and Allen, 1987).
The oceanic response to summer and winter wind patterns
are most notable near the coast. The equatorward winds of
summer can produce nearshore upwelling, while the divergent
5
wind flow of winter can force downwelling in some areas
(Rienecker and Mooers, 1986).
The shifting of the Pacific High, along with the
Aleutian Low moving to the southeast, can cause the winds to
diverge near Cape Mendocino (located at about 400 N) during
the winter. North of the Cape, northerly winds are
encountered as the wind blows around the eastern side of the
Aleutian Low, while south of the Cape, southerly winds
result as wind flows around the North Pacific High.
The summer wind pattern is established by the
interaction between the North Pacific High and the thermal
low in the southwest United States (Nelson, 1977; Halliwell
and Allen, 1987). Winds are predominately equatorward on
both sides of Cape Mendocino during the summer (Nelson,
1977).
Climatological wind stress fields, shown in Figure 2.6
for the months of January, April, July, and October, depict
regions of maximum wind stress in the CCS as shaded areas.
The strongest wind stress is located off Point Conception in
April and migrates northward until it is at a maximum in
July off Cape Mendocino. The average summer wind stress
close to the shore is equatorward and is thus favorable for
upwelling at the coast (Halliwell and Allen, 1987; Nelson,
1977; Wickham ej al., 1987).
6
C. IL NIIO-SOUTEMN OSCILLATIXN
One large-scale two way coupling of the atmosphere and
ocean has been studied for many years and is referred to as
the El Niflo-Southern Oscillation (ENSO). El Niflo refers to
the warming of Eastern Pacific ocean waters, while the
Southern Oscillation is an atmospheric pressure fluctuation
between the Indian Ocean and the Eastern Tropical Pacific
Ocean (Philander, 1990). Figure 2.7 illustrates key
properties of the teleconnection including upper troposphere
and surface pressure anomalies. Note the shift in the
Eastern Pacific Subtropical High during an ENSO event.
Explanations for this phenomena involve both an oceanic
and atmospheric teleconnection. Rienecker and Mooers (1986)
explain that the oceanic connection occurs when eastward
propagating equatorial Kelvin waves turn poleward upon
impacting the west coast of the Americas. In contrast, the
atmospheric teleconnection links the tropical sea surface
temperature (SST) anomalies to the Aleutian Low by momentum
transfer through an intensified Hadley Cell circulation
(Bjerknes, 1966; Philander, 1990). A stronger poleward wind
stress subsequently develops at the coast near 360 N when
the Aleutian Low deepens and moves to the southwest.
Simultaneously the North Pacific High weakens and moves
offshore.
The El Nifto of 1982 - 1983 was one of the strongest on
record. The Aleutian Low was much deeper than normal during
7
the winter and wind stress anomalies were at a maximum in
the region between 350 N and 450 N (Trenberth et al., 1990).
Anomalous conditions were observed from San Diego to
Vancouver Island (Rienecker and Mooers, 1986). There were
two anomalous peaks in the SST, the first occurring in
February to March of 1983 off northern California, while the
second one was evident in September to October of 1983 near
Point Conception (Rienecker and Mooers, 1986), the latter
equatorward of our model domain.
D. NUMERICAL MODEL STUDIES
There have been numerous models used over the past few
decades to model EBCs. particularly the CCS. Extensive
reviews can be found in Allen (1980), Chelton (1984), and
O'Brien = al. (1977). No attempt is made to provide a
comprehensive review of the models here; instead, a summary
of modeling work that has led directly to this study is
presented.
Early work included that of Pedlosky (1974) and
Philander and Yoon (1982) who used steady wind stress and
transient wind forcing, respectively. Carton (1984) and
Carton and Philander (1984) investigated the response of
reduced gravity models to realistic coastal winds. At
periods exceeding 100 days the alongshore currents began to
weaken and disperse as a series of alternating jets.
8
Another series of experiments were done by McCreary eJ
Al. (1987) utilizing a linear model with both transient and
steady wind forcing with Laplacian diffusion in which no
eddies or filaments developed. This work was extended using
a full primitive equation model by Tielking (1988) who
obtained similar results.
Batteen t al. (1989) used a primitive equation, multi-
level model with biharmonic heat and momentum diffusion
which had both steady forcing constant throughout the domain
and meridionally varying forcing. In both cases, when the
baroclinic shear between the surface current and
undercurrent became strong enough, eddies and filaments
developed. This was the first EBC model to simulate
currents, eddies and jets in the CCS.
The work of Batteen r& &1. (1989) was extended by
Mitchell (1993) and Haines (1994). Mitchell (1993) forced
the model with different sets of averaged winds and obtained
reasonable results utilizing a set of seasonally varying
full climatological wind fields. Haines (1994) enlarged the
model domain, improved resolution to 8 x 13 km and used
interannual vice steady or seasonal winds.
This effort builds on the model used by Batteen et al.
(1989) and the work of Mitchell (1993) and Haines (1994).
The computer code for the model has been modified to include
a barotropic component, while the model resolution has been
refined to 8 x 11 km grid spacing. Seasonal and interannual
9
wind forcing was used to force the model. Model simulation
times have been expanded from one year, as in Mitchell
(1993) and Haines (1994), to two to four years for each
model run. The enhanced simulation times should allow
analysis of the maintenance of currents and eddies as well
as the generation of these features.
10
50-
47.5-IN Columbia River
1: 45 - ccC-CUC
w42.50- DC
'40 -
Pon ConceptionM 35
IC
32.5-SCE
30--140 -135 -130 -125 -120 -115 -110
Longitude (degrees west)
Figure 2.1 Generalized circulation schematic of theCalifornia Current System (CCS). The broad, slow surfaceequatorward California Current (CC) overlies the polewardCalifornia Undercurrent (CUC) along with the Inshore Current(IC), also known as the Davidson Current (DC), SouthernCalifornia Countercurrent (SCC), and Southern CaliforniaEddy (SCE).
11
128OW 126 W 124 0 W 122 0 W
:.... .. Cape Mendocino
4()0 N-
Point Arena
+41
• 38 N"- -" San Francisco
.....................
..........
Monterey
Figure 2.2 Section of California Current System withschematized positions of jets and synoptic-scale eddies; C,cyclonic eddy; A, anticyclonic eddy. Arrows indicateprincipal surface flows; solid arrows are definite and openarrows are inferential. Also shown is a qualitativeanalysis of satellite infrared image gray shades for sea-surface temperature (SST) predominant patterns on 1 August1982: coolest SST, crosses; warmest SST, dots (from Mooersand Robinson, 1984).
12
50-
47.5- • •Columbia River
:: 45 0 0 " 0 0
0w 42.5LM• Cape Mendicino
"0
"a,
Point Conceptionm 35, •
3 2 .5 - • -
30--140 -135 -130 -125 -120 -115 -110
Longitude (degrees west)
Figure 2.3 Domain of model off the western coast of theUnited States of America. Domain bounded by 350 to 47.50 Nand from the coast to 12.5 degrees offshore. Model coversan area 1024 km (1408 km) in the cross-shore (alongshore)direction and the cross-shore (alongshore) horizontalresolution is 8 km (11 km).
13
Vb .
Hickey
Su,. .• . •. S.
' % -40.
Wickham et &I
St3*
14
;-
Figure 2.4 Map of a portion of the west coast of NorthAmerica, showing the location of some of the past studies inthe CCS (from Huyer r& al, 1989).
14
a Atmospheric PressureH
(mb)/05
.60-04
02.5
Figure 2.5Logermanamospheric pressure a e eeformb (a)Z Jaur5n b uy fo ue18)
15
'0i ; .II
16IDw
161C L
kl , A - - -
Figure~ 2. Logtr 15 -17)ma id tes(ye*m2 byoedge0qaefo hprprs(esn
1977).~~~~~~~~~~~ Cotuscrrsodt ontn antue f05
1.0,~~~~~~ ~ ~ ~ an 1. ye m2 ra hr h idsrs xed
1. dne c -2ar sadd frm.....193)
16-~~ - . ~,
Figure 2.7 An illustration of the distributions of keyproperties involved in the teleconnection process during atypical 91 Nifto-Southern Oscillation event. (Left) Uppertroposphere anomalies of geopotential height for theNorthern Hemisphere winter. (Right) Contours of surfacebarometric pressure, with surface wind anomalies (arrows) inthe tropics (from Enfield, 1989).
17
18
111. MODEL DESCRIPTION AND EXPERIMNfTAL DESIGN
A. MODEL DESCRIPTION
1. Basic Model
The model used in this research is a slightly
modified version of that used by Batteen et al. (1989, 1992)
which was adapted from Haney's (1974, 1985) closed basin
model. This limited area EBC model is multi-level, uses
non-adiabatic primitive equations on a P plane, and has both
barotropic and baroclinic components. The following
approximations are made: hydrostatic, Boussinesq, and rigid
lid. (For a more detailed summary of the model and the
governing equations, refer to Batteen r& al. (1989)).
2. Friction
The type of diffusion used can be important for the
generation of mesoscale eddies. Biharmonic rather than
Laplacian lateral heat and momentum diffusion is used in
this study. The use of biharmonic lateral diffusion allows
mesoscale eddy generation via barotropic (horizontal-shear)
or baroclinic (vertical-shear) instability mechanisms, or
both, as Holland (1978) and Holland and Batteen (1986) have
shown. The biharmonic coefficients are the same (i.e., 2.0
X 1017 cm4 s"1) as used in Batteen e= al. (1989). Weak (0.5
cm2s"1 ) vertical eddy viscosities and conductivity are used.
19
A simplified quadratic drag law is used to parameterize
bottom stress (Weatherly, 1972).
3. Boundary Conditions
The domain of the model on the eastern boundary is
closed and is modeled as a straight, vertical wall. A no-
slip condition on the alongshcre velocity is used. The
kinematic boundary condition of no flow through the eastern
boundary is imposed on the cross-shore velocity component.
A modified version of the radiation boundary conditions of
Camerlengo and O'Brien (1980) is used for the open
boundaries to the south, west, and north.
At the surface, the rigid lid approximation filters
out external gravity waves and allows a longer time step.
On the ocean bottom, no vertical heat flux or vertical
velocity is allowed.
4. Domain and Resolution
The domain of the model is an elbow shaped region
off California's coast from 350 N to 42.50 N as shown in
Figure 2.3. This covers an area 1408 km alongshore and 1024
km in the cross-shore direction. The horizontal resolution
is 8 km in the cross-shore direction and 11 km in the
alongshore direction. Mesoscale features within the CCS
should be resolvable with this resolution because typical
eddy wavelengths are around 100 km (Breaker and Mooers,
1986). Bottom topography and variations in the coastline
20
have been omitted to focus on the role played by wind
forcing in the CCS.
5. Finite Difference Schme
A staggered grid model, using the Arakawa and Lamb
(1977) B-scheme is used in the horizontal. Variables are
defined as follows: u, v, and w are velocity components
eastward, northward and vertical, respectively, t denotes
time, T is temperature, p is density, p is pressure, and
is the streamfunction. The center of each grid point
defines u and v while T, p, 4, w, and p are defined at the
corners. The B-scheme is used because it gives a superior
representation of the geostrophic adjustment process
(Batteen and Han, 1981).
The model uses ten layers in the vertical, with
constant z-levels at depths of: 13, 46, 98, 182, 316, 529,
870, 1416, 2283, and 3656 m. This spacing scheme
concentrates more layers above the thermocline in the
dynamically active portion of the ocean, consistent with
Haney (1974). Variables are staggered in the vertical with
u, v, p, and T defined at each level, while w and p are
defined between the levels which lie between the ocean
surface (w%-0) and at the bottom (z--H, where H is the
depth). A Matsuno time step followed by ten leapfrog time
steps is used and continuously repeated during the model
run.
21
6. Method of Solution
The method of solution is straightforward with the
rigid lid and flat bottom assumption because the vertically
integrated horizontal velocity is subsequently non-
divergent. The vertical mean flow can be described by a
streamfunction 0 which can be predicted from the vorticity
equation, while the vertical shear currents can be predicted
after the vertical mean flow is subtracted from the original
equations. The other variables T, p, w, and p can be
explicitly obtained from the thermodynamic energy equation,
equation of state, continuity equation, and hydrostatic
relation, respectively.
7. Initial Conditions
An exponential temperature profile with a vertical
length scale of h-450 m is used as the initial mean
stratification. The bottom temperature is assumed to be 20
C and the change in temperature between the bottom and
surface is 130 C. This profile was derived by Blumberg and
Mellor (1987) and has been used by Batteen (1989) and
Batteen et al. (1989).
B. WIND AND ATMOSPMEIC FORCING
The winds used to force the model are from the European
Centre for Medium-Range Weather Forecasts (ECMWF) (Trenberth
r& al., 1990) and have been provided by the National Center
for Atmospheric Research (NCAR). Winds were extracted from
22
world wide mean monthly wind velocities that were provided
at 2.5 degree spacing for the years 1980 to 1989 along with
120 month climatology for the area of study. This data was
linearly interpolated in space and then in time to provide
daily forcing at the desired grid points.
The total heat flux across the surface is initially set
to zero by choosing an initial air temperature that forces
the net flux of longwave radiation, sensible heat, and
latent heat to zero, as in Batteen e= al. (1989). The air
temperature is then used in the model. Any subsequent
surface heat flux forcing is thus a secondary effect of the
changes to SST due to the wind and/or thermal structure of
the ocean.
C. SPECIFIC EXPERIMENTAL DESIGN
Climatological winds were used for 365 days (Experiment
1) and then used to restart the model to run climatological
winds for another 365 days (Experiment 4). Next, 1981 winds
were run for 365 days (Experiment 2) and used to initialize
the run of 365 days with 1982 winds (Experiment 5). Then
1983 winds from a cold restart were run for 365 days
(Experiment 3) and then used to initialize the run of 366
days (leap year) with 1984 winds (Experiment 6). Two
additional extended runs were conducted in which the model
ran for four years. Experiment 7 used the climatological
23
winds four times, while Experiment 8 used the monthly winds
of 1981 through 1984.
D. ENERGY ANALYSIS T3CZNIQUZS
The energy technique used is the same as that used and
described in Batteen et al. (1992), and is based on that of
Han (1975) and Semtner and Mintz (1977). This is done to
gain a better understanding of the flow within the CCS and
of the types of energy transfer during unstable flow. A
brief summary of the method follows.
Kinetic energy (K) is calculated for the horizontal
components. After quasi-steady state is reached where the
total kinetic energy is nearly constant, mean and eddy
kinetic energies are calculated using the averaged sum of
squared mean and eddy horizontal fields, respectively.
Next, the available potential energy is calculated and used
to determine when a quasi-steady state is reached and when
statistics should be collected. Then, both mean and eddy
available potential energy are computed.
The energy transfers follow that of Semtner and Mintz
(1977), and are used to argue for the type of instability
mechanism (e.g., barotropic, baroclinic, or mixed) which
leads to the initial eddy generation in each experiment.
24
IV. RESULTS OF EXPERIUMTS
Experiments 1 through 3 study the effects of forcing a
model ocean domain that is initially at rest. Experiment 1
uses monthly climatological average (1980 - 1989) wind
fields, while Experiments 2 and 3 use monthly average wind
fields for 1981 and 1983, respectively. Experiments 4
through 6 study the effects of forcing a model domain that
has been spun up by the wind field from the previous year.
Experiment 4 uses the results of Experiment 1 as the start
for a second year of climatological average wind fields,
while Experiment 5 and 6 use the results of Experiment 2 and
3 as the start for 1982 and 1984, respectively. Experiments
7 and 8 use the results of longer (4-year) time runs from
climatological and 1981 - 1984 wind fields, respectively, to
examine the maintenance of features after initial spin up.
A. EXPERIMENTS STARTED FRC( REST
1. Experiment 1 - Climatological Winds
Experiment 1 was forced with monthly averaged
climatological (1980 - 1989) winds. Figure 4.1 depicts the
monthly wind patterns over the model domain starting with
January 15 (day 15) and ending on December 15 (day 345).
The atmospheric pressure pattern for January has a low to
the north and a high to the south which results in a wind
25
divergence near 400 N (Figure 4.1a). This pattern of
poleward winds north of 400 N and equatorward winds to the
south, continues through February and March (Figures 4.1b
and c). During April and May (Figures 4.1d and e), the
divergence in the wind flow is observed to migrate poleward.
By June (Figure 4.1f), an equatorward component in the wind
field is observed along the entire model domain. July,
August, and September (Figures 4.1g through i) depict the
strongest and most equatorward winds. By October (Figure
4.1j), the winds start to weaken throughout the domain and a
divergence in the wind flow is observed in the north. This
divergent wind flow pattern continues through November
(Figure 4.1k). By December (Figure 4.11) the wind
divergence has returned to around 400 N.
In response to the prevailing poleward winds in the
north, a relatively weak poleward coastal surface current of
-3 cm s-1 was observed by model day 30 (Figure 4.2). It
retreated further northward until by day 60 (not shown) it
was not discernible. An equatorward surface current was
observed along most of the coast by model day 90 (Figure
4.3) due to the prevailing equatorward winds over most of
the model domain. A poleward undercurrent, caused by the
meridional variation of the wind field (Batteen etal.,
1989), first became evident at model day 60 (Figure 4.4),
and was fully established by model day 90 (Figure 4.5).
26
Along with the equatorward surface current,
upwelling also occurred and was discernible by day 120
(Figure 4.6). Meanders in the equatorward surface current
formed by model day 210 and are evident in both the velocity
and temperature contour plots (Figures 4.7 and 4.8,
respectively). By model day 240, meanders began to form
cold core, cyclonic eddies as seen in the temperature
contour and velocity plots (Figures 4.9 and 4.10,
respectively) due to vertical and/or horizontal shear
instabilities between the equatorward jet and the poleward
undercurrent. The eddies initially appear to be about 30 km
(Rossby radius of deformation) in diameter and extend about
100 km off the coast, and appear during the period of
maximum wind stress (July - September).
The coldest temperatures due to upwelling were
reached by model day 240. After model day 270 no upwelling
was discernible (not shown). At the end of the year,
meanders and eddies in a weak equatorward surface current
were still present (Figures 4.11 and 4.12). A very weak
poleward coastal surface current (not shown), and a poleward
undercurrent were also present at the end of the year
(Figure 4.13). Note that no filaments developed during this
first climatological year.
Except for the lack of development of filaments,
these model results are consistent with available
observations cited in the literature. For example, the
27
eddies have rotational velocities of around 50-80 cm s-1
which is in agreement with observations of Mooers and
Robinson (1984). The poleward undercurrent is relatively
weak (-5 cm s-1 or less) and is in agreement with available
observations by Huyer e= al. (1989).
A time series of total kinetic energy per unit mass
over the entire domain is shown in Figure 4.14. In this
figure there are around three periods when the kinetic
energy becomes quasi-steady. These time frames correspond
to model days: 207 - 216, 228 - 231, and 297 - 303. Since
meanders and/or eddies appeared during these time periods,
more detailed analysis was performed on these intervals to
determine the type of instability mechanism that could
generate these features. Barotropic instability can result
from horizontal shiar while baroclinic instability can
result from vertical s,•ear in the current. As Figure 4.12
shows, there is considerable horizontal and vertical shear
between the equatorward surface current and the poleward
undercurrent. As a result, both types of instabilities
(mixed), can be present simultaneously. Energy transfer
calculations which consist of barotropic (mean kinetic
energy to eddy kinetic energy) and baroclinic (eddy
potential energy to eddy kinetic energy) components were
performed on the three time frames above.
The results for the instability analyses for these
periods are summarized in Table 4.1 (see Appendix A for the
28
energy transfer plots for this experiment), and show the
following: For model days 207 to 216, 228 to 231, and 297
to 303 both barotropic and baroclinic (i.e., mixed)
instabilities were present in the coastal, equatorward
region of the domain. Additional analysis of model days 297
to 303 shows barotropic instabilities to be weak (Figure
A.5) and baroclinic instabilities to be dominant (Figure
A.6) during this period.
2. Experiment 2 - 1981 Winds
Experiment 2 was forced with the monthly ECMWF winds
from 1981. Figure 4.15 depicts the monthly wind patterns
within the model domain starting with January and running
through December. Unlike the climatological winds, January
starts off with poleward flow throughout the model domain
(Figure 4.15a). February (Figure 4.15b) shows the typical
wind divergence at 400 N, consistent with the climatological
data. March through June (Figures 4.15c through f) depict
the wind divergence moving poleward and also shows the wind
speed increasing to a maximum in June, especially in the
southern half of the region. Figures 4.15g and h (July and
August) depict strong winds and equatorward flow throughout
the model domain. By September (Figure 4.15i), the wind
divergence reappears in the north and migrates equatorward
over the remaining three months of the year (Figures 4.15J
to 1). By December the wind divergence is at 37.50 N
29
(Figure 4.151), which is around 2.50 farther equatorward
than the climatological wind divergence.
As in Experiment 1, a relatively weak poleward
coastal surface flow -2 cm s-1 was observed in the poleward
region of the model domain (Figure 4.16). In response to
the wind pattern, an equatorward surface current was
observed along most of the coast by model day 90 (Figure
4.17). A weak poleward undercurrent became evident by model
day 90 (Figure 4.18), and became as large as 5 cm s-1 in
layer 5 (316 m) by day 210 (Figure 4.19).
Upwelling of temperatures cooler than 150 C was
observed by model day 120 (as observed in the climatological
run), as seen in Figure 4.20. Meanders in the surface
current also formed by the same model day as in the
climatological run (day 210) as depicted in the velocity and
temperature contour plots (Figures 4.21 and 4.22,
respectively). By model day 270, the first sign of eddies
appear (see the velocity and temperature contour plots of
Figures 4.23 and 4.24), which is -30 days later than in the
climatological run. The amplitude of the meander of the
coastal current increases to the south as a result of the
stronger equatorward winds in this region. Again, these
eddies are cold core, cyclonic, and about 30 km in diameter.
Upwelling of the coldest surface water oc-urred by
model day 240 (not shown), corresponding to the period of
strongest equatorward winds. Upwelling did not disappear
30
until model day 330 (not shown), which is -60 days later
than the climatological results. At the end of the year,
meanders in the equatorward surface current along with
embedded eddies remain (Figure 4.25). A poleward
undercurrent is also discernible at the end of the year
(Figure 4.26). A very weak poleward coastal surface current
(not shown) has reappeared in the poleward region of the
model domain. As in Experiment 1, no filaments developed
during this experiment.
Figure 4.27 shows the time series of total kinetic
energy per unit mass over the entire domain for 1981 and
shows four periods when the kinetic energy becomes quasi-
steady, model days: 210 - 222, 240 - 252, 297 - 303, and
309 - 333. Energy transfer plots were obtained for these
periods and yielded mixed (i.e., both barotropic and
baroclinic) instabilities in all cases in the coastal,
equatorward region of the model domain. These results are
summarized in Table 4.1 (see Appendix B for the energy
transfer plots for this experiment). During the time frame
297 to 303, barotropic instability (Figure B.5) was much
greater than baroclinic (Figure B.6) instability.
3. EZxperiment 3 - 1983 Winds
Experiment 3 represents the El Nifto year of 1983 and
was forced with the monthly winds depicted in Figure 4.28
representing January through December. The year starts off
31
with predominantly poleward winds for the first three months
as seen in Figures 4.28a - c. April shows a change in the
wind pattern as equatorward winds are present throughout
(Figure 4.28d). These winds remain equatorward and
strengthen from May through September (Figures 4.28e -i).
The winds weaken in October (Figure 4.28j). A divergence in
the wind field appears near 380 N during November (Figure
4.28k) and remains through December (Figure 4.281).
In response to the three consistent months of strong
poleward winds at the start of 1983, a poleward coastal
surface current with velocities as high as 5 cm s-1 is
established by model day 30 (Figure 4.29) and remains
through model day 60 (not shown). By model day 120 an
equatorward surface current develops along most of the coast
(Figure 4.30). A weak poleward undercurrent is present at
model day 90 as seen in Figure 4.31, and strengthens to
around 6 cm s-1 by model day 195 (not shown).
Upwelling and meanders both appear by model day 150
(Figure 4.32). The meanders are also discernible in the
velocity plot (Figure 4.33). Note that the meanders appear
farther poleward than in the previous experiments. Eddies
start to form by model day 240 as seen in the velocity
(Figure 4.34) and temperature (Figure 4.35) fields. As in
the previous experiments, these eddies are cold core and
cyclonic.
32
The coldest upwelling temperatures were reached by
model day 240 but were warmer (only 14.00 C as compared to
13.50 C and 11.50 C for climatology and 1981, respectively)
than observed in previous runs. No upwelling was
discernible after model day 270. By the end of the year,
meanders in the equatorward surface current along with
embedded eddies (Figure 4.36), a weak poleward coastal
current (not shown), and a poleward undercurrent (Figure
4.37) were discernible. As in the previous experiments, no
filaments developed during the experiment.
Figures 4.38a and b show the time series of total
kinetic energy per unit mass for 1983. Quasi-steady periods
that prompted additional evaluation were, model days: 186 -
192, 222 - 234, 249 - 258, 279 - 288, 312 - 315, 324 - 327,
and 342 348. The results for the instability analysis for
this year are summarized in Table 4.1 (see Appendix C for
the energy transfer plots). Every period showed mixed (both
barotropic and baroclinic) instabilities to be present. The
instability analysis for model day 279 to 288 was the only
case where one type of instability was noticeably greater
than the other, and in this case barotropic (Figure C.7) was
greater than baroclinic (Figure C.8).
4. Sumary of First Year Run Results
Table 4.2 summarizes the climatological, 1981, and
1983 experiment runs for the first year. In all first year
33
runs, both a surface equatorward current and a poleward
undercurrent developed. There was also a poleward coastal
surface current present during the winter season. Upwelling
was a seasonal feature which, as expected, had the coolest
temperatures during a non-El Niflo year (1981) and warmest
temperatures during an El Niflo year (1983). Both meanders
and eddies were generated. The eddies were cold core,
cyclonic, and had a size around the Rossby radius of
deformation (30 km). Along with an equatorward surface
current, both meanders and eddies remained at the end of
each year. Instability analyses revealed that both
barotropic and baroclinic processes were important eddy
generatiol. mechanisms. In all first year runs, no filaments
were observed.
B. EXPERIMENTS SPUN UP FROM THE PREVIOUS YEAR
1. Experiment 4 - Climatological Windu
Experiment 4 was forced with the same monthly
averaged climatological winds as in Experiment 1 (Figure
4.1). In this experiment, the model was continued with the
spun-up output from Experiment 1, rather than starting from
rest. For convenience this experiment is referred to as
'Climo III because climatological winds are used a second
time.
In response to the wind forcing, an equatorward
surface current was observed by model day 396 (year day (yd)
34
30) (Figure 4.39). Embedded in this current are meanders
and cyclonic eddies (Figures 4.39 and 4.40). A weak
poleward coastal surface current was also present initially
(not shown). A poleward undercurrent was established by
model day 426 (yd 60) (Figure 4.41).
Upwelling was observed by model day 546 (yd 180)
(Figure 4.42), and peaked by model day 606 (yd 240) (Figure
4.43), with a minimum temperature near 120 C. Cessation of
upwelling occurred by model day 726 (yd 360) (not shown).
In previous model runs anticyclonic meanders were
observed, but they did not close off to form anticyclonic
eddies. During this experiment, in addition to the
predominantly cyclonic eddies, a warm core anticyclonic eddy
(defined by closed contour in streamline plot - not shown)
formed by model day 456 (yd 90) (Figure 4.44). This
anticyclonic eddy persisted for the remainder of the year.
Figure 4.45 is a cross section in the middle of the
domain and depicts the broad meanders in the CC along with a
strong core of the CUC near 250 m in depth. Between model
days 696 (yd 330) and 726 (yd 360), an eddy formed as the
result of a pinched-off meander (Figures 4.46 and 4.47). A
filament was observed during this experiment by day 606 (yd
240) and extended about 300 km offshore (15i C isotherm)
near 40* N (Figure 4.43).
A time series of total kinetic energy per unit mass
over the entire domain is shown in Figure 4.48. Four
35
periods were investigated further because the kinetic energy
became quasi-steady. These time frames correspond to model
days: 378 - 408 (yd 12 - 42), 453 - 465 (yd 87 - 99), 504 -
516 (yd 138 - 150), and 624 - 636 (yd 258 - 270). All four
of these periods consisted of both barotropic and baroclinic
instabilities. These results are summarized in Table 4.3
(see Appendix D for the energy transfer plots for this
experiment).
2. Experiment 5 - 1982 Winds
Experiment 5 was forced with monthly winds from
1982. This experiment continues the spun up case using the
output of Experiment 2 (1981) as a starting point, rather
than starting from rest. Figure 4.49 shows the monthly wind
patterns within the model domain starting with January and
running through December. January starts with the typical
divergent flow, this year slightly to the north at 420 N
(Figure 4.49a). February moves the divergence equatorward
to 400 N and has weaker winds to the south (Figure 4.49b).
The flow in March is onshore throughout the model domain
with a slight poleward component in the north (Figure
4.49c). April has the divergence at 42.50 N (Figure 4.49d).
May starts the all equatorward flow and is the strongest
(Figwue 4.49e), this regime continues in June (Figure 4.49f)
through October (Figure 4.49i). A divergent flow returns in
October at 42.50 N (Figure 4.49j), and migrates equatorward
36
to 38.50 N in November (Figure 4.49k) and remains in
December (Figure 4.491).
As in the previous experiment, the year starts with
a fully developed equatorward surface current which contains
embedded meanders and eddies (Figure 4.50). Also present is
an anticyclonic eddy, and a poleward surface coastal current
in the northern part of the model domain (Figures 4.50 and
4.51). A relatively strong (-9.5 cm s-1) poleward
undercurrent is present by model day 426 (yd 60). A cross
section in the middle of the domain (Figure 4.52) shows this
feature along with a strong subsurface flow associated with
an eddy (Figure 4.53).
Upwelling began by model day 516 (yd 150) (Figure
4.54), and peaked by model day 606 (yd 240) (Figure 4.55).
The coolest water observed was around 12.00 C. The
upwelling ceased by model day 696 (yd 330) (Figure 4.56).
Four cyclonic eddies and one anticyclonic eddy were
preser. e.g., Figure 4.53) throughout most of this
experiment. The size ranged between 30 and 150 km in
diameter and the westward propagation of these larger
features was around 500 km. As in Experiment 4, a filament
was observed during this experiment. By day 600 (yd 234)
(not shown) this filament extended about 350 km offshore
near 38.50 N. A cold core eddy pinched off from this
filament by day 606 (yd 240) (Figure 4.55).
37
A time series of total kinetic energy per unit mass
over the entire domain was produced (Figure 4.57), and
showed two quasi-steady periods for additional study. These
were model days: 507 - 516 (yd 141 - 150), and 525 - 528
(yd 159 - 162). As in the previous experiments, the energy
transfer plots indicate the presence of both barotropic and
baroclinic instabilities. Table 4.3 summarizes these
results (see Appendix E for the energy transfer plots for
this experiment).
3. Experiment 6 - 1984 Winda
Experiment 6 was forced with monthly winds from
1984. This experiment continues the spun-up case using the
output of Experiment 3 (1983) as a starting point, rather
than starting from rest. Figure 4.58 shows the monthly wind
patterns within the model domain starting with January and
running through December. January has a divergent flow at
430 N (Figure 4.58a), while February shows that the
divergence has moved equatorward to 398 N (Figure 4.58b).
From March through May (Figures 4.58c through e), the wind
divergence moves from 410 N to 430 N and the winds become
stronger. June is the start of equatorward wind flow
(Figure 4.58f), which continues through July and August
(Figures 4.58g and h). In September, the wind divergence
reappears in the north at 470 N (Figure 4.58i). During
October and November, the divergence migrates equatorward to
38
370 N (Figures 4.58i and k). The year ends in December with
weak winds along the coast with a divergence at 400 N, and
with predominantly equatorward winds further off the coast
(Figure 4.581).
At the start of the experiment, there is a well-
developed equatorward surface flow with embedded meanders
and eddies (Figure 4.59). There is also a weak poleward
coastal surface current in the northern corner of the model
domain which remains until model day 426 (yd 60) (Figure
4.60). A relatively strong (-10 cm s-3) poleward
undercurrent is evident, as seen in a cross-section in the
middle of the model domain, at model day 546 (yd 180)
(Figure 4.61).
Upwelling begins by model day 456 (yd 90) (Figure
4.62). Corresponding to the period of maximum equatorward
winds, the peak occurs at model day 576 (yd 210) (Figure
4.63) in which cooler temperatures of around 100 C are
present along the entire coast. This year had upwelling of
cooler water earlier than previous years and also had the
coldest water which was a result of the strong equatorward
winds. Cessation of the cooler water occurs by model day
726 (yd 360) (not shown).
The eddies are around 90 km in diameter and stay
within 300 km of the coast. A filament occurs by model day
666 (yd 300) (Figure 4.64). This filament is observed near
39
380 N as a plume of 150 C wateL .id extends about 200 km off
the coast.
The time series plot of total kinetic energy per
unit mass over the entire domain is shown in Figure 4.65.
The kinetic energy is still fluctuating because the model is
still spinning up during the first part of the year. Three
periods were selected for additional study, model days: 576
- 591 (yd 210 - 225), 606 - 624 (yd 240 - 258), and 645 -
657 (yd 279 - 291). All of these included both barotropic
and baroclinic instabilities, and are sunmnarized in Table
4.3 (see Appendix F for the energy transfer plots for this
experiment).
4. Summary of Second Year Run Results
Table 4.4 summarizes the follow-on (second year)
model runs. In general, a weak coastal poleward surface
current was evident during the winter season in the northern
region of the domain for all years (Climo II, 1982 and
1984). A meandering equatorward surface current, already
present, at the start of these experiments was maintained.
A poleward undercurrent was generated in all experiments.
The eddies, already present at the start of the experiments,
were both cold core, cyclonic, and warm core, anticyclonic
eddies in Climo II and 1982, while in 1984 there were only
cold core, cyclonic eddies. The size and offshore extent of
the eddies were consistent with the first experimental runs.
40
Seasonal upwelling occurred with minimum temperatures of
-120 C for Climo II and 1982, and of -100 C for 1984. The
year 1964 had the largest extent of cool upwelled water as
expected for a year with the strongest equatorward winds.
Filaments developed in all three experiments, but was most
pronounced (as expected) in 1984. The filaments had an
offshore extent between 200 and 350 km. Instability
analyses revealed that both barotropic and baroclinic
processes were involved in eddy generation.
5. Experiment 7 - Multiple Climatological Runs
Experiment 7 was an extended climatological run in
which the climatological winds used in Experiment 1 (Figure
4.1) were used in repetition four times. The third and
fourth years of the run follow Experiment 4 (Climo II) and
are dubbed "Climo III" and "Climo IV", respectively. (The
values in the model on the last day of a run were retained
for use at the start of the next run, rather than starting
from scratch or rest as is done in a cold restart.)
In response to the wind forcing, an equatorward
surface current was observed by model day 760 and 1125 (yd
30) for Climo III and Climo IV, respectively (not shown).
Embedded in this current were meanders and cyclonic eddies
(not shown). A weak poleward coastal surface current was
also present initially (not shown). A poleward undercurrent
41
was evident early on by model day 820 and 1185 (yd 60) for
Climn III and Climo IV, respectively (not shown).
Upwelling was observed by model day 850 and 1215 (yd
120) for Climn III and Climo IV, respectively (not shown).
The upwelling peaked by model day 970 (yd 240) for Clima III
(not shown) and day 1305 (yd 210) for Clima IV (not shown),
with a minimum temperature near 110 C. Cessation of
upwelling occurred by model day 1060 (yd 330) for Clime III
(not shown), and was still present in small patches by day
1455 (yd 360) for Climo IV (not shown).
Figure 4.66 and 4.67 show the total kinetic energy
per unit mass time series over the entire domain for Climeo
III and Clime IV, respectively. Climn III has a peak
kinetic energy of 166 cm2s"2 around model day 915 (yd 185)
while Climo IV has a peak of 145 cM22s 2 at model day 1293
(yd 198). Figure 4.68 depicts the total kinetic energy per
unit mass time series for all four ciimatological runs
together. It clearly shows that the first and second runs
were involved in the generation or spin-up of features in
the model, while the third and fourth runs oscillated about
125 cm-2s 2 and indicate the maintenance of these features
(i.e., a quasi-steady state).
6. Experiment 8 - Multiple Years (1981 - 1984)
Experiment 8 was a run of two additional years of
the model using the monthly winds of 1983 (Figure 4.28) and
42
1984 (Figure 4.58). This experiment differs from Experiment
3 (1983) which was started from scratch (cold restart). The
runs in this experiment followed in succession after
Experiment 5 (1982), and used the values in the model on the
last day of the year as input to the restart.
In response to the wind forcing, an equatorward
surface current was observed by model day 760 and 1125 (yd
30) for 1983 and 1984, respectively (not shown). Embedded
in this current were meanders and cyclonic eddies (not
shown). A weak poleward coastal surface current was also
present initially (not shown). A poleward undercurrent was
evident by model day 820 and 1185 (yd 60) for 1983 and 1984,
respectively (not shown).
Upwelling was observed by model day 880 (yd 150) for
1983 (not shown), and day 1155 (yd 60) for 1984 (not shown).
The upwelling peaked by model day 940 and 1305 (yd 210) for
1983 and 1984, respectively (not shown). The minimum
temperature was near 110 C for both 1983 and 1984, but 1983
had only patches of this water while 1984 had this cool
water along the entire coast. Upwelling was still present
in small patches by day 1090 and 1455 (yd 360) for 1983 and
1984, respectively (not shown).
Figure 4.69 and 4.70 are the total kinetic energy
per unit mass time series over the entire domain for 1983
and 1984, respectively. The year 1983 has a peak kinetic
energy of 128 cm2 s" 2 around model day 963 (yd 233) and 1984
43
has a peak of 215 cm2s" 2 at model day 1368 (yd 273). Figure
4.71 depicts the runs for all four years (1981 through 1984)
together on one total kinetic energy per unit mass time
series. It appears that the first year (1981) as seen in
Experiment 2 and the second year (1982) as seen in
Experiment 5, were involved in generation or spinning up of
the model. The third year (1983), which was an El Nifto
year, had an energy level on par with 1982, so that no
increase in kinetic energy occurred. In the fourth year
(1984), the energy level increase significantly to the
highest value (215 cm2s' 2 ). Comparing this figure to the
climatological time series (Figure 4.68) for the last two
years shows that the maximum (1984) and minimum (1983)
kinetic energies lie on either side (as expected) of the
climatological year. During a non-El Nifo year, as is 1984,
features such as equatorward currents and upwelling would
strengthen while during an El Nifo year, as in 1983, these
features would be weaker.
7. Sumary of Multiple Year Run Results
Table 4.5 summarizes the last two years of the
extended (four year) runs. Listed here are Climo IV, 1983,
and 1984. Similar results are obtained: A poleward coastal
surface current, a surface equatorward current, a poleward
undercurrent, along with embedded meanders and eddies. Of
interest, upwelling occurs later in 1983 (at yd 150) than
44
for the other years (yd 60 to yd 90). Although the minimum
temperature is the same (11.00 C) for all years, 1984
experienced a larger area of cooler water (all along the
coast) than that of the El Nifio (1983) year. In all
experiments, there were both cold and warm core eddies.
Finally, filaments were observed during Climo IV and 1984,
but not during 1983.
45
TABLE 4.1 SUMMARY OF INSTABILITIES FOR CLIMATOLOGICAL YEAR(TOP), 1981 (CENTER), AND 1983 (BOTTOM).
MODEL DAYS FEATURE TYPE INSTABILITY LOCATIONfor (Meander, (Barotropic, (Coastal,
Climatology Eddy, Both) Baroclinic, Offshore,Mixed) Both)
207-216 Meander Mixed Coastal
228-231 Meander Mixed Both
297-303 Both Mixed Both
MODEL DAYS FEATURE TYPE INSTABILITY LOCATIONfor (Meander, (Barotropic, (Coastal,
1981 Eddy, Both) Baroclinic, Offshore,Mixed) Both)
210-222 Meander Mixed Coastal
240-252 Meander Mixed Both
297-303 Both Mixed Both
309-333 Both Mixed Both
MODEL DAYS FEATURE TYPE INSTABILITY LOCATIONfor (Meander, (Barotropic, (Coastal,
1983 Eddy, Both) Baroclinic, Offshore,Mixed) Both)
186-192 Meander Mixed Coastal
222-234 Meander Mixed Both
249-258 Meander Mixed Coastal
279-288 Meander Mixed Coastal
312-315 Both Mixed Both
324-327 Both Mixed Both
342-348 Both Mixed Both
46
TABLE 4.2 SUMMARY OF EXPERIMENTS - FIRST YEAR.
FEATURE CLIMO 1981 1983
Sfc Poleward -1-60, & -1-60, & -1-60, &330-360 days 330-360 days 330-360 days
Sfc Equatorward -90 days -90 days -120 days
Undercurrent -60 days -120 days -60 days(poleward only)
UPWELLING:(<15 o C) ___
Start -120 days -120 days -150 days
Maximum -240 days -240 days -240 days(min temp) (13.00 C) (11.00 C) (14.00 C)
Cessation -270 days -330 days -270 days
Start -210 days -210 days -150 days
EDDIES:_______
Start -240 days -270 days -240 days
Core cold cold cold
Rotation cyclonic cyclonic cyclonic
Size (diameter) -30-60 km -30-60 km -30-80 km
FILAMENTS:
Start none none none
Offshore n/a n/a n/aextent
47
TABLE 4.3 SUMMARY OF INSTABILITIES FOR CLIMATOLOGICAL II YEAR(TOP), 1982 (CENTER), AND 1984 (BOTTOM).
MODEL DAYS FEATURE TYPE INSTABILITY LOCATIONfor (Meander, (Barotropic, (Coastal,
Climo II Eddy, Both) Baroclinic, Offshore,Mixed) Both)
378-408 Both Mixed Both(12-42)
453-465 Meander Mixed Coastal(87-99)
504-516 Both .xed Both(138-150)
624-636 Both Mixed Both(258-270)
MODEL DAYS FEATURE TYPE INSTABILITY LOCATIONfor (Meander, (Barotropic, (Coastal,
1982 Eddy, Both) Baroclinic, Offshore,Mixed) Both)
507-516 Both Mixed Both(141-150)
525-528 Both Mixed Both(159-162) _
MODEL DAYS FEATURE TYPE INSTABILITY LOCATIONfor (Meander, (Barotropic, (Coastal,
1984 Eddy, Both) Baroclinic, Offshore,Mixed) Both)
576-591 Meander Mixed Coastal(210-225)
606-624 Meander Mixed Coastal(240-258)
645-657 Meander Mixed Coastal(279 -291)
48
TABLE 4.4 SUMMARY OF EXPERIMENTS SECOND YEAR.
FEATURE CLIKO II 1982 1984
CURRIENTSSfc Poleward -366-426 -366-426 -366-426
(1-60), & (1-60), & (1-60), &696-726 696-726 696-726(330-360) (330-360) (330-360)days days days
Sfc Equatorward -396 days -396 days -396 days(30) (30) (30)
Undercurrent -426 days -426 days -546 days(poleward only) (60) (60) (180)
UPWELLING:(<15 0 c) CStart -546 days -516 days -456 days
(180) (150) (90)
Maximum -606 days -606 days -576 days(min temp) (240) (240) (210)
(12.00 C) (12.00 C) (10.00 C)
Cessation -726 days -696 days -726 daysMANDRS: (360) (330) (360)
Start -396 days -396 days -396 days(30) (30) (30)
Start -396 days -396 days -396 days(30) (30) (30)
Core cold & warm cold & warm cold
Rotation cyclonic & cyclonic & cyclonicanticyclonic anticyclonic
Size (diameter) -30-90 km -30-150 km -30-90 km
FILAMENTS:
Start -606 days -600 days -666 days(240) (234) (300)
Offshore -300 km -350 km -200 kmextent
49
TABLE 4.5 SUMMARY OF EXPERIMENTS - MULTIPLE YEARS.
FEATURE CLIKO IV 1983 1984
CURRENTS: _______, _______ .... __,__,,,_,,
Sfc Poleward -1096-1215 -731-850 -1096-1185(1-120), & (1-120), & (1-90), &1395-1455 1060-1090 1425-1455(300-360) (330-360) (330-360)days days days
Sfc Equatorward -1125 days -760 days -1125 days_,_(30) (30) (30)
Undercurrent -1155 days -790 days -1155 days(poleward only) (60) (60) (60)
UPWELLING:(<15 o C)
Start -1185 days -880 days -1155 days(90) (150) (60)
Maximum -1305 days -940 days -1305 days(min temp) (210) (210) (210)
(11.00 C) (11.00 C) (11.00 C)
Cessation -1455 days -1090 days -1455 days(360) (360) (360)
MEANDERS: ______________
Start -1125 days -760 days -1125 days(30) (30) (30)
EDDIES:.______. __. ___ ___._________ _______.____. _
Start -1125 days -760 days -1125 daysI_(30) (30) (30)
Core cold & warm cold & warm cold & warm
Rotation cyclonic & cyclonic & cyclonic &Ianticyclonic anticyclonic anticyclonic
Size (diameter) -30-80 km -30-80 km -30-80 km
FILAMENTS:
Start -1305 days none -1305 days(210) (210)
Offshore -350 km n/a -350 kmextent
50
:imo (OfRO fig) Winds - day 1% Climn (11160- N0) Winds day 4!.
/////// / I I I l!,/ / , .,- / / ,
/1 / / / / / , F I / I , .9,-, / I 1li ' 4 110l1. 4
771 , / / / / , / , , 77(1 / , ." 9 I , •
77 0 'p77A
S,, / / , , -. -. . . .. . 9/,, - - .. . .
76E, /" - , - 66.. - -.. .
I 9 -ý . . . - -, " - - 'q \
l.4 22.3 43.7 69.8 86.3 187.7 129.a 1.9 77.3 43.7 65. 116 1 16? 7 12"1 i
-limo (19R(0-6) Winds. -day 75 Clima (1980 119) Winds day 105
20.0 I/u
•161 4 113.4.-*-" t .-" - /" -. - 9" 9 / /
77 1 77 1
5, , . . . . • ,
-" - N. \\\ \ \ \ \.
7'!. .. . "• \ \ 266 *
Longitude Longitude
Figure 4.1 Mid-monthly averaged climatological (19801989) ECMWF winds in m s- : (a) January, (b) February, (c)March, (d) April, (e) May, (f) June, (g) July, (h) August,(i) September, (j) October, (k) November, and (1) December.The latitudinal grid point 1 (129) corresponds to 350 N(47.50 N); so that the latitudinal grid point of 52corresponds to 400 N. Maximum wind vector is 20 m s"1.
51
Clmro (1980 69) Winds day 135 Clina (19060 - ) Winds -day 166
i~~~'9~ 1 29 -8
18:1 4 183.4
52 2 522-
2b 26 6
I . 22 V\ 3.7 N 6%. \6\ Vi' 7 1 9 1 ý 1 6. 63%' )
-- * Clinso (1980- 89) Winds -day 195 Clirna (1980-89) Winds -day 225MAXIMMUIO20.0 r/
1111 4 103A4
7/ 0 17.8-
12? 52,2-
26 6 26 6-
6 223 13 V~ a--6\ 221~6~~ r', 'i \I,0o1giLude longitude
Figure 4. 1 (continiued).
52
CInto (1980 89) Winds -day 255 Chima (1980 so) Winds -day 285
IY a. A- -A1
16.1 4 133 4
,, II 17 II
92 2 52 2
SI ' \ \ \" , ,,
26 6 26 6-
i j \ \ \ 1 \ \
.1 22.3 43. P 6 .0 86.3 197 1 1298
- Clino (1980 89) Winds -day 315 CIrnoo (1980-BO) Winds -day 345MXINUM "INDS
20.0 U/S
129 a -- *. I. I , A. 129.6- J-- ..- L -. _.... _
1011 4 163.4-
26 6;26 6
' " .'" -,- '-, ., -• ' - ; A , " / ' /'- '-* - • • - • - , '/ "
;02 3 43 7 65 a 0. 3 1 8 129 0 M 22 3 43 7 65.6 ofý 3 lei 7 1 ý) a
Longitude Logiaitude
Figure 4. 1 (continued).
53
Distance off shore (km)
-1324.3 -953.3 -692.7 -512.3 -341.3 -173.7 3.3
140P.9- I I I 1. - -
0
-- - - -. _---
1173.3--- ,-
•'a "-- -- k....
0"I -
214.7- ,',";-
S* II--- I"'. I,
0 .8 " "
Figre4.2 Exeiet1 uraemrdoalcmoeto
0J ' +,1
C,,1 I I l,,
+ w vlc69y3 $7 -he -
I,,,
*It'llli g"II*
?)34 . 7 - |% -l iiI •
L II.11.1IIIIlgIp
IRorth-South vel contour at. model day 30.0 'I
Figure 4.2 Experiment 1: Surface meridional component ofvelocity at day 30. The contour interval is 1 cms.'. Thedashed lines indicate equatorward velocities. The maximumpoleward velocity is -3 cm s"1* Latitudinal alongshoredistance 0 (1408) km corresponds to 350 N (47.50 N).
54
Distance off shore (kin)
-1024.0 -853.3 -682.7 -512.1 -341.3 -170.7 8.0
1409.0 - I I
1173.3-
939.7 -
0m 784.8-
to93
-U 469.3-
2344.7 -
Velocity at model day 90.0
Figure 4.3 Experiment 1: Surface velocity vectors at day90. To avoid clutter, velocity vectors are plotted at everythird grid point in both the cross-shore and alongshoredirection, and velocities less than 5 cm s1 are notplotted.
55
Distance off shore (kin)
-1024,6 -853.3 -682.7 -512.6 -341.3 -170.7 6.6
0.0- .! t..-- . --. -H ,s
-151 .6l-H~me I.I,, I• it
- 302.1 - Ras
-453.1 (J-ۥ -694.2-- L-.Im
-755.2-
- • 6 3 -I!II1
-1024.0 -953.3 -692.7 -512.6 -341.3 -117.7 6.9
North-South velocity at model day 60.0
Figure 4.4 Experiment 1: Cross-section at y-704 km
(41.250 N) of the meridional component of velocity at day60. Dashed lines indicate equatorward flow, while solidlines indicate poleward flow.
56
Distance off shore (km)-1024.0 -,53.3 -682.7 -512..8 -341.3 -1,7N.7 @Ae
'.9-- I I. I I
I I -o
-151 .0-
-102.1 , --
- 604.2 -
-1824.8 -853.3 -682.7 -512.6 -341.3 -170.7 6.,
North-Sotith velocity at model day 90.0
Figure 4.5 Experiment 1: Cross-section at y-704 km(41.250 N) of the meridional component of velocity at day90. Dashed lines indicate equatorward flow, while solidlines indicate poleward flow.
57
Distance off shore (kin)
-1524.9 -953.3 -692.7 -512.3 -341.3 -175.7 U.6
146• . I I It
1173.3- 18
q38.7-
0I~k g18
A 704.0-
0
C.)
•-- 469.3-M t8
234.7-
"18
Temperature contour at model day 120.0
Figure 4.6 Experiment 1: Surface temperature at day 120.The contour interval is 10 C. The temperature decreasestowards the coast.
58
DisLance off shore (kin)
-1924.0 -853.3 -682.7 -512.9 -341.3 -17.7 F..
1438.9- _________ ___
1173.3- I
III
I
936.7 II
I
II.
U3I
/
4J 49.31.7- I0 /
.74.3-
o / / I"--I, 1/ 1
U)/I /1 1Imi i n
4-' 469..'3-
i1/I II//// I
I /1/1/ I
/ IlI
Fiue4.7- IEI S i -
210 ToI avi ltevlctvcosaepotda
II IllII/ II/ III
/1 II ~II
Velocity at. model day 210.0 ***
Figure 4.7 Experiment 1: Surface velocity vectors at day210. To avoid clutter, velocity vectors are plotted atevery third grid point in both the cross-shore andalongshore direction, and velocities less than 5 cm s-1 arenot plotted. Note start of meander at y-500 km.
59
Distance off shore (kin)
-1024.0 -n53.3 -682.7 -512.fl -341.3 -170f.7 0.9
1 173.3-
'130. 7 -
0)
• 7014.0J --
o
-• 469.3--
~j4 4
PIA. 7 --
' 1 8
e. - t I_ __t1
Temperature contour at model day 210.0
Figure 4.8 Experiment 1: Surface temperature at day 210.The contour interval is 10 C. The temperature decreasestowards the coast. Note start of meander at y-500 km.
60
Distance off shore (kin)
-1024.0 -8A 3 3 -682.7 -512.0 -341.3 -170.7 0.9
II I ! I
1173.3-
9138.7 -
t•t0 .4
13
00
234 .7-
14
18-
Temperature contour at model day 240.0
Figure 4.9 Experiment 1: Surface temperature at day 240.The contour interval is 10 C. The temperature decreasestowards the coast. Note the formation of cold core eddy aty-230 km.
61
Distance off shore (k1m)
-1824.0 -B53.3 -682.7 -512.0 -341.3 .170.7 O.R
M40N 0- I I -
IIII
II
1171.3- ! -
IISII
II''II
938.7- II
U, III3o €/11
Veoct at4. moedy24.
oe "f c ec
20 as in Fiue43 oetefrmto fcl oeed
i/// ! "m t/1/I
at y-2.30-k. The/ nube asoitdwth o ty70k
'/// /
/41
I37 II ,k
I I
I~ I,1 " -
Velocity .t. model day 240.0 2u•_,ln*XIMI• vrf flnn
Figure 4.10 Experiment 1: Surface velocity vectors at day240 as in Figure 4.3. Note the formation of cold core eddyat y~230 km. The number associated with the low at y-700 kmcorresponds to temperature, not velocity.
62
Distance off shore (kin)
-1024.0 -853.3 -682.7 -512.0 -341 .3 -170.7 8.8
14(nR1 P- -I I___
1173 1-
9n.7 -
0J1 704.0-to•
00A69.3-
0.8-
Temperature contour at model day 360.0
Figure 4.11 Experiment 1: Surface temperature at day 360.The contour interval is 10 C. Note meanders and eddies arestill discernible in temperature contours.
63
Distance off shore (kin)
[email protected] -953.3 -682.7 -512.0 -341.3 -179.7 3.0
143ne0- ! I I IIII
I II
'i Ii
1171.3- 1
toI
4697,.3- I
II,,I
3.7- IIIII,
liVc ay
"Al-.O ilr iol
o I,
II!
II
III"
III 1
Velocity at model day 360.0 ._
Figure 4.12 Experiment 1: Surface velocity vectors at day360 as in Figure 4.3. Note equatorward surface current overa poleward undercurrent. The number associated with the lowat y-800 km corresponds to temperature, not velocity.
64
Distance off shore (kin)
-1024.9 -953.3 -692.7 -512.8 -341.3 -17F.7 0.
- " " " ' - 4 . 1" -
I- . " - "0- .' "
-~~ 79. -
-151. - 5.7 - . ,341. -170.7 a"." ""S-' " " - " I
,- -392.1 -- -"" .8 , " ' J -
F-i43. - Ex. 10
co -6 oyt. 2 - 3 e-
- 795.2 -
-99e6.3 - I I'
-1924.9 -953.3 -692.7 -512.9 -341.3 -179.7 9;.9
North-South velocity &t model day 360.0
Figure 4.13 Experiment 1: Cross-section of the meridionalcomponent of velocity at dlay 360. Note meanders and eddiesare still discernible in a weak equatorward surface current.
65
Kinetic Energy vs. Time65 1T TT-- I 1 I 1
60
55
45
- 40 -(V
U* 35
N,
'2 io
• 25
15
0 50 lo 150 200 250 300 391 4AS
Time (days)
Figure 4.14 Experiment 1: Total kinetic energy per unitmass time series for climatological (1980-1989) year overthe entire domain (Units of the kinetic energy are cm2 s 2 ).
66
101 Winds -day 15 Io 111u, 1 • ,l..y 45
'• ~ t t t I I o • . .- .- ," / ,"I /
1/ 1t " "A /m/ ,7'I
CO ~ < ' < 4 1 r T Ai * i~ ' " , VP /
a b
' / /1 / I 4 / ,,
20/ ,, , / / / / .. . 0--,
10 14 10:1 4
-1 P
26
C IS
I0 2) 1 41 1 ,', 0 oil, 1 1l, , i r 0 21 ., 1 0- -0I !g i l a id e 1
a tii l d y
Figure 4.15 Mid-monthly ECMWF winds for 1981 in m a-1:(a) January, (b) February, (c) March, (d) April, (e) May,(f) June, (g) July, (h) August, (i) September, (j) October,(k) November, and (1) December. The latitudinal grid point1 (129) corresponds to 350 N (47.50 N); so that thelatitudinal grid point of 52 corresponds to 400 N. Maximumwind vector is 20 m a1
67
1961 Winds day 135. 19111 Winds day 16,5
.#1 Il 1! I , I , I I , *• l I * I * I , I I ,
* - , .. , • . P _ t • . • . • ..
191 14 191 4
eI
i1tl 1 4 1111 4
' 4 I 1I II
_• ..... . .\ \ \ \ \ . .- ,-, \ \ \ \
266
---- ÷ IIl0l Win~ds day 195 I198l Winls day 22."i)MAZIU WIITNIHDS
20.0 u/ul
. iiiii11 t , \ \ \\\\ \\ \
LO,)•tucleI~ongitudc
Figure 4.15 (continued).
68
.9111! widl day 255 1901, Wilds ?M,) •II!:
l~ ' l • I , I I I *a I , I * I
--. \,, \ \ \ ",10 1 4 I101 4
6 2)6 6
- ... ~ 19011 Winds day :115 10111 Winds day :1I5HAXIMMU WINIDS
20.0 u/O
101 4 181 4
* -. -. \ \ \ .. .. \/,, /\ \ \ / / / /
.......... ,-\ \. \ \/ -... ... ,A,, \ //,/,/
)f, 6 ~~~16 b '- - - -
I 3 411 6, 0 .161 I Is? 129 14 2)3 4:1 1 6 ',a 1163 Is/ I
lo.n1git wi c 1igtudc
Figure 4.15 (continued).
69
Distance off shore (kin)
-M124.0 -853.3 -682.7 -512.0 -341.3 -17f 7 8.014 80e.0 - U o It I1I ,I~ _
1173,3- --
0 -.
0
00t /• ~ ~ " - II
0 Loi •-, 0../
I 0It
7946 . --..- ,I --
o I.,i
"I"
234.7 -. I,,
!'.,
'i,
North-South vel contour at model day 45.0
Figure 4.16 Experiment 2: Surface meridional component ofvelocity at day 45. The contour interval is 1 cm s"-. Thedashed lines indicate equatorward velocities. The maximumpoleward velocity is -2 cm s-1. Latitudinal alongshoredistance 0 (1408) km corresponds to 350 N (47.50 N).
70
Distance off shore (kin)
-1,24., -853.3 -682.7 -512.3 -341 .3 -17f.7 0.0
1173.3-
q38. 7 --
S704.8-- 1 _In
469. 3-
.7- 1--
0.0-
Velocity at model day 90.0 _0IJl kmllI- VrIOIne
Figure 4.17 Experiment 2: Surface velocity vectors at day90. To avoid cluLter, velocity vectors are plotted at everythird grid point in both the cross-shore and alongshoredirection, and velocities less than 5 cm s"- are notplotted.
71
Distance off shore (kin)
-1024.0 -653.3 -682.7 -512.0 -341.3 -171.7 5.6S* -• - - -" - -°Ia . . lIo . . . "
~lI.8 - - . e -. - - I1.g -- .-
-151."5 L-... La, -
,,• -453.1I
S~L-.tel .t L_.n _.4. -1 4 2
-604.2- L.* k.k. k,
-755.2-
-1024.5 -853.3 -682.7 -512.8 -341.3 -175.7 9.A
North-South velocity at model day 90.0
Figure 4.18 Experiment 2: Crcss-section at y-704 km(41.250 N) of the meridional component of velocity at day90. Dashed lines indicate equatorward flow, while solidlines indicate poleward flow. Note weak polewardundercurrent.
72
Distance off shore (kin)
-1824.0 -853.3 -682.7 -512.3 -341.3 -170 7 0.0
148. I
1174 .3 -
234. 7 -
III
0.0-4.0 -
II
- 49,37 - 91 -
Velocity at model day 210.0
Figure 4.19 Experiment 2: Layer 5 (316 m) velocity vectorsat day 210. The maximum poleward velocity is 5 cm s'l neary-469 )an.
73
Distance off shore (km)
-1324.3 -893.3 -692.7 -512.3 -341.3 -176.7 a.V
1408.3- I I I
1173.3-
0WI.9 704.0g--
tM
0-4
0a
469.3--U,,
234 . 7
•.9 - - -
Temperature contour at model day 120.0
Figure 4.20 Experiment 2: Surface temperature at day 120.The contour interval is 10 C. The temperature decreasestowards the coast.
74
Distance off shore (km)
192.4,0 -853 3 -682.7 -512.6 -341.3 -170 7 3
In 7
liIivi'iII
'II'IIIIII
S,''I
oi/
0 ,
V/ /,,S// /ll
0
U ///' Jill
4 f7/- - /suIo.' -/ ----- I
,,A7-/1/"l//Il.... I
'1/]/// llit'' -I1//I- 11111
I///i/ III
Velocity at model day 210.0
wlll f InsPl
Figure 4.21 Experiment 2: Surface velocity vectors at day
210. Note the meander near y-469 kIm.
75
Distance off shore (km)
1074 a -RC3,1 1 -682 7 -,17 I -341 3 179 7 9.0
- /70or
apaId
Vu
t14 2 _ N I 2
Temperature contour at model day 210.0
Figure 4.22 Experiment 2: Surface temperature at day 210.The contour interval is 10 C. The temperature decreasestowards the coast. Note the meander near y-469 km.
76
l)Ist•, o ff shore (km)
"1C4 ll 60 1. -341 3 -173.7 0.6
I In P L - I II-IIIIII,Ii
1~II IiIiIfIIII
'II
-
o I -
Vlct att moe a 7..
SI
corespnd to tepraue not veoiy.Ntteed
/1/I I
Ill,/// II
lii
I II //| II
III, / 11
SI'll' I
corrspods t teperaure not velo ity Noe h ed
near y-600 km.
77
Distance off shore (km)
-1024.0 -893.3 -602.7 -512.0 -341 .3 -170.7 ".0
1408 .- - I RI _
1173.3-
Q•R. 7-
0704 P-
ol
h 469,3-
714 7 - S .-
e.g,- I B"
Temperature contour at model day 270.0
Figure 4.24 Experiment 2: Surface temperature at day 270.The contour interval is 10 C. The temperature decreasestowards the coast. Note the cold core eddy near y-6000 km.
78
Distance off shore (kin)-102•4.0J -853.3 -682.7 -512•.9 -341 .3 -170.7 @•."
140 .0 -- !-- ---I I ,
fqem
1173A.3-
I H
918.7-
469.1-It
M
C18
IT
2•.14.7 - !, •
Temperature contour at model day 360.0
Figure 4.25 Experiment 2: Surface temperature at day 360.The contour interval isn 1 C. The temperature decreasestowards the coast. Note existence of meanders and embeddededdies.
79
Distance off shore (kin)
-1824.1 -953.3 -692.7 -512.0 -341.3 -173.7 3.0
',,.O .' -.1,, , *.
-- 3o - - * - l
-. '1S2 I --. 8" -"S-453.1 -0 - _
II
-76 3- -n n--1324.3 -853.3 -632.7 -512.3 -341.3 -173.7 3.6
North-South velocity et model day 360.0
Figure 4.26 Rxperiment 2: Cross-section at y- 7 04 kin(41.250 N) of the meridional component of velocity at day360. Dashed lines indicate equatorward flow, while solidlines indicate poleward flow. Note existence of polewardundercurrent.
so
K;netic Energy vs. Time
• -
60
U 50(V
N
U 40
w
10 -
0 so IN• 15 2M 291 190• 4A
Tline WAlY"l
Figure 4.27 Experiment 2: Total kinetic energy per unitmass time series for 1981 over the entire domain (Units ofthe kinetic energy are m2s92} . Quasi-steady periods: days210-222, 240-252, 297-303, and 309-333.
81
190:1 Wsinds day 16 1983 Winds day 45
'" /1/1 /1 /11 1'/;1 11 1 1/ // // // /ll / 33 / / /1 /1111I 1
""////////i¢ "9//I//f IiIu:1
9
36 ,'///i /,,,. 36 7/ 1/////1/ ,. * / 5 , ,2 /
a b
a 22 3 43 7 65 0 86 3 17.1 .1393 1.0 22.3 43.7 65.3 06.3 107 1;2299
MAITUM ... . 1 1:1 "i14S day 75 190 Wilnds day 105
20.0 I/a
t2l 0 1,| • j .| j I • L "129 .__I -- |.._L_..... L_-i _A I
\ i I
I 1 I I I I l Ii -
292 4 923.4
r I-I I 1 1. N \
S~,,ii,,i/ I I,,
\S \ \ \S \s \. \. S
.. //dI'\ \ \ \ \ \ \
.-. 5,
03- .. a.A.. '# 7/ /" /r , -'-"23 • • ,
2 2 3 43 1 (5 8 06 3 101 7 239 6 2 2.3 43.1 65 0 06 3 10? 1 129 0
lzngitudc loigi-tude
Figure 4.28 Mid-monthly ECMWF winds for 1983 in m 9'1:(a) January, (b) February, (c) March, (dý April, (e) May,
(f) June, (g) July, (h) August, (i) September, (j) October,
(k) November, and (1) December. The latitudinal grid point
1 (129) corresponds to 350 N (47.50 N); so that the
latitudinal grid point of 52 corresponds to 400 N. Maximum
wind vector is 20 m s".
82
1903 Winds --day 135 19N3 Winds day 165
- -\ \ \ \ 12 .
I1I 4 163 4
- N -. -\ -. -. -, "
IU 0 17.8
'i) 292 2
26 6 26.6
0 f
- 1983 Winds -day 195 1986 Winds day 225KA13I4UK WINDS
20.0 0/-
18:3 4 10e: 4
a -- --'- '..'.'. \ ',. \ ',, N, ', \ \ \ \ \ \ \' \0 1
• .",.\ \ \\\ ',\\ \ \\ \ \ \ \ -
26,6 26.6,.,•, \\\ \\ \., ,,, \ \ \\\\\\\ .
1 ... 6 ?Al j.' 7\ 8 8% 0 9 22t -3,7V X ,. 8
i~oigitudc ~LonglLude
Figure 4.28 (continued).
83
108:1 Wlind --day 255 1903 Wields day 2115
-,\ \ \\\ \ t '18:1 4 161 4
", \\ \ \ I I I . . .
52 2
1 2273-'j431 F .0O 8N7 2 9 1.0 2
9 22.3 43.a
-~1903 Winds -day 315 1983 Winds day 345KaZZNM~ WINDS20.0 .1.a
* I \ ., I £ 1.I.I *i~ I * 129 L.L.L'..L . .8 I a.
*I -- t--,- -// I I I I I I I I ,
123 4 183.4
/)9 -. ~~ ~ / / / 1 77 8 .
v
S2 ;1 SP 2.A / I- . - . -
26 6 26 6-;
-" - P" -- I- -. .. 1.0 - - A .
26 7- -+: J: -•. •o: -" 6- --'- -,-- +-v ,- t -+, ,.
11 22.3 43,7 65.0 86.3 lf? 7 129 1 . 22,3 43.7 615.0 .b 3 -17.i 1 i 0
Longitude longitude
Figure 4.28 (continued).
84
Distance off shore (kin)
-102A4. -853.3 -682.7 -512.1 -341.3 -17N.7 ".a
117M 3--
qrnl. 7 -
Ix
140
0
g.
-~469.3-
234.7 -
9.9-
Velocity at model day 30.0 _M_2._MAXlI MIIM ¥V"W'W I I
Figure 4.29 Experiment 3: Surface velocity vectors at day30. To avoid clutter, velocity vectors are plotted at everythird grid point in both the cross-shore and alongshoredirection, and velocities less than 5 cm s-1 are notplotted. Note poleward flow to the north of y-1200 km.
85
Distance off shore (kin)
-1624.0 -853.3 -682.7 -512.1 -341.3 -171.7 P.A
140n.e- I I I I
1173.3-
')9f1 . 7 -
0I
0
7141I-UI"
.-2 I
o) IC) I
469.3-
S~I
34•7- I
Velocity at nodel day 120.0HA•lg-m, vrftnn
Figure 4.30 Experiment 3: Surface velocity vectors at day120. To avoid clutter, velocity vectors are plotted atevery third grid point in both the cross-shore andalongshore direction, and velocities less than 5 cm a-' arenot plotted. Note equatorward surface current dominates.The number associated with the high at y-250 km correspondsto temperature, not velocity.
86
Distance off shore (kin)
-,924.9) -653.3 -682.7 -512.8 -341.3 -179.7 @.P"-- ""- -'- '-"" I • % -,
-151 ,@ -A.0- II.oO .
-• - 43 . I - .1 _
-453.1- I.
L-.,4
•799. 2 - -..
-1024.0 -853.3 -682.7 -512.9 -341.3 -170.7 @.A
North-South velocity at model day 90.0
Figure 4.31 Experiment 3: Cross-section at y-70 4 km(41.250 N) of the meridional component of velocity at day90. Dashed lines indicate equatorward flow, while solidlines indicate poleward flow.
87
DIstance off shore (km)
,ga4 a OKI 3 62 7 5i1 0 -34d1 3 170 7 I.9
14pfl . . I . .. _ ........ A- -
1171 1
"7.18 7 -
I,",
LO0
MA 7R4.R -
0)
()
41 469.3-
034.7 -7
Temperature contour at model day 150.0
Figure 4.32 Experiment 3: Surface temperature at day 150.The contour interval is 1° C. The temperature decreasestowards the coast. Note the existence of upwelling andmeanders.
88
Distance off shore (kin)
t 824 p _953 . -,2 7 -S12 3 3d' 3 li 7 36
II
140RI 9 - '-
A 70490--
II-
in0
IdI
0
0
274 .7 -
9.9-
Velocity at model day 150.0
Figure 4.33 Experiment 3: Surface velocity vectors at day150. To avoid clutter, velocity vectors are plotted atevery third grid point in both the cross-shore andalongshore direction, and velocities less than 5 cm sa arenot plotted. The number associated with the high at y-850km corresponds to temperature, not velocity. Note themeanders near y-938 km.
89
Distance off shore (km)
1974 li60 1 67 7 S12 6 341 3 170 7 P S
140" 0
11171 1
SIII'III
II
153fl 7 '1II'I
III'I,
lis
6) III
'4 III
W'I
0.Fiur 4.4 Eprmet3 ufcevlct lecosa a
2 . T olo
km/ ce
o /i/ -
./ I//Ji
Ill Il
Io d I de
II 9
Velocity at model day 240.0__,___,
Figure 4.34 Experiment 3: Surface velocity vectors at day240. To avoid clutter, velocity vectors are plotted atevery third grid point in both the cross-shore andalongshore direction, and velocities less than 5 cm s"I arenot plotted. The number associated with the high at y- 2 50km corresponds to temperature, not velocity. Note existenceof eddies.
90
Distance off shore (km)
-1624.9 -953 3 -682.7 -512.8 -341.3 -1W7 7 .6
4 0. 8 -- - -I I I I I
11 71.3-
g .q0.7 -
70 46to
00
69.3-
214.7-1I:
" .6 - I
Temperature contour at model day 240.0
Figure 4.35 Experiment 3: Surface temperature at day 240.The contour interval is 10 C. The temperature decreasestowards the coast. Note existence of eddies.
91
D)istance off shore (kin)
-1624. -853.3 -682.7 -512.6 -341.3 -171.7 1.1
468.8- I ! I I
1173 1-
0
0 I
469.3 --
IBIs
FU r- 18T ------ IAL
Temperature contour at model day 360.0
Figure 4.36 Experiment 3: Surface temperature at day 360.The contour interval is 10 C. The temperature decreasestowards the coast. Note eddies remain at end of year.
92
Distance off shore (km)-1324.3 -953.3 -692.7 -512.9 -341.3 -17N.7 S.A
- 3•. 3I-i v- • I ;l~ .,_'. -"
, . - - .- ,.,
-S • ' V , -
R-O I -.
151 . 11- 1W-
0 -R4.S2 -
-9053.---r
- I I•
-124 .9 -t953.3 -62.7 -512.3 -341.3 -173.7 3.9
North-Soft~h velocity at model day 360.0
Figure 4.37 Experiment 3: Cross-section at y-704 km(41.250 N) of the meridional component of velocity at day360. Dashed lines indicate equatorward flow, while solidlines indicate poleward flow. Note poleward undercurrentremains at end of year.
93
Kinetic Energy vs. Time
4C-
40F
319
NNUU
2• 5
9~
N
N
U
w 20
15-
F 20 40 60 80 100 120 140 160 180 200 220 240 260 2FS 300 320
Time (days)
Figure 4.38a Experiment 3: Total kinetic energy per unitmass time series for 1983 (days 1-306) over the entiredomain (Units of the kinetic energy are cm2 s- 2 ). Quasi-steady periods: days 186-192, 222-234, 249-258, and 279-288.
94
K;nelic Energy vs. Time5'.5 -rTI i-r~vtl--t v | v w -r , ' •vI vv I v' w I i , I--rfr• --- v t |r -ii
5-.
49 9
F
US
' 49.0
LLJ
N
4 6 . 9 1 1 u_ I -JL-L I _. .J I _ L I -i - i t- t i I I i , i I t i I I i i i I i t j 1- - i t , II L L JL L LI I I I I I L 1 I
306 316 326 336 346 356 366
Time (days)
Figure 4.38b Experiment 3: Total kinetic energy per unitmass time series for 1983 (days 309-363) over the entiredomain (Units of the kinetic energy are CM2g"2) . Quasi-steady periods: days 312-315, 324-327, and 342-348.
95
Distance off shore (kin)
-1924. -9513 3 -682.7 -512.8i -341.,3 -171W 7 5.3
I ~I_____ -
111111tIl, I1111 I!111 I
toI
CI!
''I'II'•''ll l l
A69.13 -_
Fi1g 4.3- E 4 11
1111111/
atlt e third g po'n i b hor
alongshore direction, and velocities less than 5 cm s"I arenot plotted. The number associated with the low at y-80 kmcorresponds to temperature, not velocity. Note equatorward
surface current with embedded meanders and cyclonic eddies.
96
Distance off shore (kin)
-1124.0 -853.3 -692.7 -512.9 -341.3 -178.7 0.9
14 03'e- I I I I -
11 73.3 -
934.7 -
W
in 7N .0 -
us 469.3--0
234.7 -
Temperature contour at model day 396.0
Figure 4.40 Experiment 4: Surface temperature at day 396(yd 30). The contour interval is lo C. The temperaturedecreases towards the coast. Note cold core eddies.
97
Distance off shore (km)
-1824.0 -953.3 -692.7 -512.0 -341.3 [email protected] 3.41.- i __ ...._ -.3- ,_- - -. f r-. -. '-- ,' . .. ,,, - u.. •./"-5"3 .-. . .. -j: --.,.
""" .-- . , ,,
- 5 5.2-. g,.-. -3112.1 - -. - , , -,,-
- - 5.*-- 14
-90l6.3 It_
4 J4
-1324.1 -853.3 -682.7 -5t2.0 -341.3 -173.7 3.3
North-South velocity at model day 426.0
Figure 4.41 Experiment 4: Cross-section at y-704 km(41.250 N) of the meridional component of velocity at day426 (yd 60). Dashed lines indicate equatorward flow, whilesolid lines indicate poleward flow. Note existence ofpoleward undercurrent.
98
Distance. off shore (k1m)
-1024.8 -853.3 -682.7 -512.0 -341 -17F.7 8.g
1480 a0-
1173.3-
10
930 7 -
to
0..
0
: 74.7-- I-
Temperature contour at model day 546.0
Figure 4.42 Experiment 4: Surface temperature at day 546(yd 180). The contour interval is 10 C. The temperaturedecreases towards the coast.
99
D)istance off shore (km)
-1024.0 -853.3 -682.7 -512.0 -341.3 -170.7 0.0
14 0.@- 1 . .-
18
1173.3-
ll8939.7-
0 -0
2.•.£7 • -
0S704.0o-
0
469.3 -8
234.7-14
Temperature contour at. model day 806.0
Figure 4.43 Experiment 4: Surface temperature at day 606(yd 240). The contour interval is 10 C. The temperaturedecreases towards the coast.
100
Distance off shore (km)
-1024.A -853.3 -682.7 -512,6 -341.3 -179.7 9.9•4999e- L... I !
AI
Velocity at tIoeldyI5IIAiWI IIio
lii II
1173.31 1 II
111Ill111 tit
1111 '\% I
at eerythir grd pint n bth he l crs-hr an
'Ill,
101|
-II-
SI I H1//)• -
o II I ,. •
0 I11//
*i 79I-I Il I i/
.2 11111 • I 1/
II 4693-- II
I ~iF- li\\
eI-.I I 1 -l -
Velocity atl model day 456.0 *SI..Ke2
Figure 4.44 Experiment 4: Surface velocity vectors at day456 (yd 90). To avoid clutter, velocity vectors are plottedat every third grid point in both the cross-shore andalongshore direction, and velocities less than 5 cm s1I arenot plotted. Note anticyclonic eddy at y-650 Iam.
101
Distance off shore (kin)
-1324.3 -853.3 -692.7 -512.3 -341.3 -173.7 3.3
S-7I
o~- ... . Z : 2 98-o - - " "" •- *.
- 33. S-- .. - • -30 .'o, ,, ..-- '~I,'~ 3, -- _ ~ S ... -,,
S'. _- • - - - .4 - - -
,. -453...4..4
c'• -63)4.2•- -
- 755.? --
-9N6.3- _ _ _ _ _ _ _ _ _ _ _ _ _-8
-1024.3 -853.3 -682.7 -512.0 -341.3 -173.7 3.3
North-South velocity at model day 666.0
Figure 4.45 Experiment 4: Cross-section at y-704 km(41.250 N) of the meridional component of velocity at day666 (yd 300). Dashed lines indicate equatorward flow, whilesolid lines indicate poleward flow.
102
Distance off shore (kin)
-1824.9 -85,.3 -682.7 -512.9 -341.3 -17".7 B."
149.8 9- I I I I 1 _20
1173.3-
93S.7 -
20
W11
0
V) . 20 lie_
o 1,,' to20
234.7- 1 ~m1
20 1 1 260 16
Temperature contour at model day 696.0
Figure 4.46 Experiment 4: Surface temperature at day 696(yd 330). The contour interval is 10 C. The temperaturedecreases towards the coast. Note formation of eddy frompinched off meander at y-469 km.
103
Distance off shore (km)
-1624.3 -853.3 -682.7 -512.6 -341.3 -170.7 6.6
1410.0- 118
1173.3-
938.7 -
Inoto
S469.3 -- lt,
'234,. 7 - i,.,
18j 16
Temperature contour at model day 726.0
Figure 4.47 Experiment 4: Surface temperature at day 726(yd 360). The contour interval is 10 C. The temperaturedecreases towards the coast. Note formation of eddy frompinched off meander at y-469 km.
104
Kinetic Energy vs. Time
130 " rr -T-- -T --
120
110
100
U
Y
7,
N
E
U -0
70-
60
• 0 * 1 t m t I t I t t I . I t ! | t I i I I |_ ._ _L I_
0 50 100 150 200 250 300 350 4V 0
Time Idays)
Figure 4.48 Experiment 4: Total kinetic energy per unitmass time series for Climo II over the entire domain (Unitsof the kinetic energy are cm2 s- 2 ). Quasi-steady periods:days 378-408 (yd 12-42), 453-465 (yd 87-89), 504-516 (yd138-150), and 624-636 (yd 258-270).
105
1012 Winds day 15 1962 Winds day 45
l < I2 I , 4 I- ,. - I -, - JI24 *I .. I.. .. 4 -__ 4. ... -n__ _, * , 4
S.. .. . ..... .. .. " - .. .. .. -. /" / / / /
• ,, ,_*.. _.. . . .. .. -A ... .. . -" .- / / / /181 4 -113 4
ab
1 21 37 6.0 16. 3 117.7 129 8 1 I 22.3 43.7 65.8 86 3 197 7 129) I
-i 1982 Winds -- day 75 1982 Winds dny 105MAXIMUM4 WINDS
20.0 alo
1211 I 4* 129 a - ~ I. a I--
101 4 113 4
". \ \ N \ \ \ \ N '. N -.,
-, ,,, H\ \ 1.7 " "
21, 6 26 6-,, .
.5 \\ \ N \\\\\ \ . ....
a S S- \ \ \ \ \ \ \ \ N
Cd
1 0 22 3 41 7 69,I 86 3 17 11 29 I IiI 1 22,3 43 1 6568 06 3 107 1 129 I0
Longitude L~ongitude
Figure 4.49 Mid-monthly EMW winds for 1982 in m a(a) January, (b) February, (c) March, (d) April, (e) May,(f) June, (g) July, (h) August, (i) September, (j) October,(kc) November, and (1) December. The latitudinal grid point1 (129) corresponds to 350 N (47.50 N); so that thelatitudinal grid point of 52 corresponds to 400 N. Maximumwind vector is 20 m s-.
106
1042 Winds day 135 1962 winds day 165
113.4-" "\129 8-
l 1J 3 4Hll II II
S2 52.2
26 6
1942 Winds --day 195 38 ~d a 2
20.0 .=/&129• * . I 11-a- ---..-I ---.- .... --- -- L .--.--I---, --. 129.6l ---- ---J------'----I -- -- L--.j -i .a -I-
~i 'I129.
10: 4l 113.4
52 2 52.2
5 7 2 6 6
I6.12?L3 • E .• \ ,,\ ,..1?, ,,q, I -'" \ \I' A'"'66 ;\,6\ \aI\ '>'Iongitude Longitude
Figure 4.49 (continued).
107
1982 Winds day 255 1982 Winds day 285
*\ \\ \\\ \ \ ,-N N N -. - o
IN:) 4 113 4
1I 8 77
S-., ---
52 2 52.?-
26 6 26.6-
. I I . .023 ,, 1 I 22.3 43.7 65.8 06.3 181.1 1"
1982 Winds -day 315 1902 Winds - day 345
20.0 ,/St29 II L _J _. - J _ -- - . . . I .. .L __ .. . 129.0 __ . - I.--. --- I - -.- I -. I --, - I -.*
-.... ... , I I / / / / / I/ III I
S. . . . - / I I / / / / / / / 1 !
113.4 163.4-- - - , 1 I' / / / , , / / / / ,
. .. . . . .- - / I / / / -p - / / / I I
.11 0 11.9--- - / I // / - -. -. - / / I I
"0- -- , / ~ / - .o / / l
a 1 0 !- -.- -I- - -I ý - - I-
•6 6*- .. 5 ,266 .. ..- /-
I a 22 3 43 7 6 6 9 06.3 17,7 1 129 I8 1a 22.3 43.7 65 I8 6.3 1 .7. 1;9 8qLongitude Longitude
Figure 4.49 (continued).
108
Distance off shore (km)
-1024.9 -853.3 -682.7 -512.9 -341.3 -176.7 0.8'498.3-- I I !
4II
111 1 7 ,3 . 3 - | ii--
Los
'111 t1
alnshr drcio.7- eoctesls tuhan 5 m - r
II I'I'tI
t e u I I It ll
with po r sufc curntnrh1fy1173 k.-.,
10
S794.9- ut \
•0 ~III1IIlI
S~IIIll/11//11-I//ill /,
p37i/i I I~ ii~~11111/
II/III'
9.9-lt II F 4
Figre4.50Exeimn 5:I Sufc veoityecor atda
alongshre diretionndvlociie lestan5c s r
sufaeluren cith embde meaders and eddis,0aongK~
withupoeard0 suprfacen curen northc eof ty-7 km.os a
39 (d 0} T aoi cuter vlolt vctrsa109ote
Distance off shore (kin)
-i924.0 -953.3 -692.7 -512.9 -341.3 -179.7 9.9
1499.9 *. I*.. -I
a aaI l IS
~ I
b I I p I ! "
. 40
469:.3-- ,q
* ' I 'I
%1 II•
-t 0
934.7- % .
-10i=. ', • '. a0'N ° ¶-1€
,*l - , o' ,,.
,c , , 30.o- , . .
7* ". a O ' 'I , -2 - * _/"
veoci. a0
8 . T e d s e i e in ic t e ut o r ve ci es Th
ma xi mu soe r ve o c ty i s -1 m - . L ti u i a
alnsoe ditac -( ket4
11~,,110
S 469.3- • 0 1 e L ; .20 , so -
-I ° I ; ** -I tO ; ; 0_ ' *' '- 0
I " 'I * -• • % II /|1 g
23 . - 0,,,, ' ,,_ -10-10 -10 1 1- 0
aximu polewar velot is -1 cm s Lattudna
aloguhre distancerien0 (108 Surfcorespelonds topo nen o4f5
N).
110
Distance off shore (kin)
-1324.3 -953.3 -692.7 -512.3 -341.3 -173.7 3.3
,'.3- ," t ' -, , - , L_.m ,, __, Ie2a5 e - -. " •~ ""- .""• " '"-T';"••lI
-113 -8, -..• -p.8 ,'t tS., -" - , -.8, -,~2-f
__ -332.1 - - " 5 -"" -" " - 'i/t 'I' -.W-2
) - 42*3 192.1 -
A S.
-755.2- III' 4 1 -. 8. ;
-906.3
-1024.3 -853.3 -682.7 -512.3 -341.3 -173.7 3.N
North-South velocity at model day 426.0
Figure 4.52 Experiment 5: Cross-section at y-704 km(41.250 N) of the meridional component of velocity at day426 (yd 60). Dashed lines indicate equatorward flow, whilesolid lines indicate poleward flow. Note strong polewardundercurrent along with subsurface flow associated with aneddy.
111
Distance off slhore (km)
-1•24.3 -853.3 -682.7 -512.3 -341.3 -170.7 9.3
14M38- I I - _IllIlIl I
4J 693- 111 1111
I23 .Ii I I
iIl Il
I O 1 1WI 1W
notplote. Th nubr asoiae wit th low embedded
/112
II2 .. ~I"\
IllIlI -
734- I/I/I'
SII tl '
.26.MA/II/ vIini
Figue 4.53 Expeiment 5:SraevlctyvcosaIa
temeraure nt vlocty
I I1 I\ \"'112• il
Distance off shore (km)
-,•124. -1151.1 -682.7 -512.3 -341.3 17N.7 V.P
146 .- I I Ir- -
- 173.3-
a,0
fm
Temperature contour at model day 516.0
Figure 4.54 Experiment 5: Surface temperature at day 516(yd 150). The contour interval is 10 C. The temperaturedecreases towards the coast.
113
Distance off shore (km)
-1024.0 -893.3 -682.7 -512.8 -341.3 -170.7 ".0
40R.- I I I18
1171.1
08
938. 7-
54
L4o
00
I., I p -
Temperature contour at model day 606.0
Figure 4.55 Experiment 5: Surface temperature at day 606(yd 240). The contour interval in 10 C. The temperaturedecreases towards the coast. Note maximum extent ofupwelling.
114
Distance off shore (kim)
-1324.6 -853.3 -692.7 -512.9 -341.3 -179.7 8.0S• .-I , I I I I._
1400i.0- __ j - --
20
is
1173.3-
20
4 37 . 70-
to
0
+j 469.3 -( -
02
d m.n
234.7-
6.9-
Temperature contour at model day 696.0
Figure 4.56 Experiment 5: Surface temperature at day 696(yd 330). The contour interval is 10 C. The temperaturedecreases towards the coast. Note the disappearance ofwater cooler than 150 C.
115
Kinetic Energy vs. Time1•~~~~~~~~~~~~~~ I- Ii•V I v w v-r- r-T- --- 7-T v-
125
120
115
NN
135
785
F1 so 100 159 200 250 3F 190 Ape
Time (dlays)I
Figure 4.57 Experiment 5: Total kinetic energy per unitmass time series for 1982 over the entire domain (Units ofthe kinetic energy are cm28-2). Quasi-steady periods: days507-516 (yd 141-150), and 525-528 (yd 159-162).
116
1911.1 Winds day 16 1984 Wind. day 46
)11* I ,-a .-. .. . . . I A" I I * I
"101 4 1I:1 4
/1 I/A.... . ,$$/9/P7//// I!
•ll / / - - \ \ o i. i A,-/ I I - I /
,-• * ' " \ \ I I / • / i ... .. I .. - ,
a , I1 \\\ I b ...
143 i.IIO6X3' 1 1) " . 1
2,3 3. a. 22.3 43.7 659 86.3 9. V I?9 II
MAI -- 19114 Winds -day 75 1l84 Wiedn day 105W4ar I J1'H NDS
20.0 0/n
/ / / / / / / / / / / .... •, • . .. .. .. . .
1I.l 4 113 4/ / ,' -9 . / / / / ....~ , ... .. .. . .. ...
/'/19 i 7---. /" A / / i"I I I.,_, . ......... . .
it II 77.11
,• '• " -.. .. .- -. -, - ,,,, /-
S -- . . .. .. -. ...\.\..N,,,\ \ \ N.
26 6 .. 26.
C d1' .q I \ .' 111 N 1"I a. , 1 '\ ' 'IX , . ,., ,,
IN 22 3 43.7 6i 8 06 ei 9 1 1 2 3I~ongi~I Ic I~ioniltuidc
Figure 4.58 Mid-monthly ECMWF winds for 1984 in m a'1:(a) January, (b) February, (c) March, (d) April, (e) May,(f) June, (g) July, (h) August, (i) September, (j) October,(k) November, and (1) December. The latitudinal grid point1 (129) corresponds to 350 N (47.50 N); so that thelatitudinal grid point of 52 corresponds to 400 N. Maximumwind vector is 20 m sa-.
117
£964 Willit -day 135 1084 Winds day 165
-. ~~~~ ~~ I - A A - - . -. - . * -. -
113 4 10:1 4
~1 a
5 2 57.?
26 6 26 6
~ I I--~ 1 -££-I~rrr~w~ r'.'1 2 "WI 6 1% 1.a 22. i3. 6\.Ia\86\ 1l2 A
NAINN IN 1 904 Winds -day 195 1984 Wsinds day 225
20.0 0/0
a ~1 -A-.a.....s.i *~~i* 129.0
10:1 4 101. 4
71l 11''~i t 11.0
9
Logitd Log~d
/11 l~\118
1884 Winds day 255 IO4 Winds -day 18
I•'I l .* -l. ._ - --J. l. -. N . _ L -_ ~ .. \ *-- -. - . , _I _, I , i
A. -A . -. - -
101 4 13 4
I) 8 11.0
112 52.2
26 6 26.6
I \ \\\\\\ ' \ \\ \
22. 3 FIr 6ý 11%1 0 1 g 22 ~ 3 77 X '0; 06' i ) 1964 Winds day 315""IKiUHlll KlINDS 1984 Winds -day 345
20.0 u/a
1 29 0 - .- l-J . _ L -. _.L . 12 9 .0 - _. LJJ I L . L L L. ._ _ _
-.. ... -.-.. .. -.. / / I I• /
103 4 1634
11 A - / / /77.8.-
k 1U 'N. . N.\ \ \ \ '
: . ,/ /i2 - •" .,. 2, *. • .. I-..-.- - 52
-*61 ... -b•I • - *"P-- .-'fr -#
\ \\ \ \ \ \ \
1 22 3 43 1 653 86.3 137.7 129.1 . 2. . 67 , 06.3 I1s 7 129 a
Iongitude Longitude
Figure 4.58 (continued).
119
Distance off shore (kin)
-1024.1 -853.3 -682.7 -512.1 -341.3 -170. 7 M.1
1408.0- I !
1173.3- 111 1
9 3 e3.7 - I I / / 1_
Q) I IIIk, III /I
0
937-Ill '~<
S~~ ~~I I I I /...-.-..
U, I , a•'40
A 469 .3 ---
.III I _ ,
234.7- 11 -• II II I, / •t I • \" I I "_-_,________.
I
Velocity at model day 396.0HAXm q "s .vrflin
Figure 4.59 Experiment 6: Surface velocity vectors at day396 (yd 30). To avoid clutter, velocity vectors are plottedat every third grid point in both the cross-shore andalongshore direction, and velocities less than 5 cm s-1 arenot plotted. The numbers associated with the low and highembedded in the meanders and eddies along the coastcorrespond to temperature, not velocity. Note equatorwardsurface flow with embedded meanders and eddies.
120
Distance off shore (kin)
-1•24.0 -95,.13 -682.7 -512.1 -341.3 -176.7 6.6
14U.R -I I , I I
0 -193P. -1
-0'.
I I
0 .
10* * I 0
6 I i 0 -
o , I P
o LU
% I tI •
234.7- / , ,'0fit'"•'"
L -.
SI -!0/," . , -'. "--' ",
"S.04 '- • - .. 0.s,.
/0
Not-ot vel cotu at mdelday:26.
S'. T veloie."I•9. - •, \ -| . , ' *, l
I 121
.- , . , - , , ,.--
, , , [ - ' -II 0 -" , ', -. I "• "-- , ,
* L." -- • 1 • l I- • ' '|I|S•, , -\ • . ... ., .,
o ,L. ' , '!X\ ,, , S , ",;..' /
S.... "-, ' ,,./ ."
North-South vet contour at model day 426.0
Figure 4.60 Experiment 6: Surface meridional component ofvelocity at day 426 (yd 60). The contour interval is 5 cms~z. The dashed lines indicate equatorward velocities.Latitudinal alongshore distance 0 (1408) km corresponds to350 N (47.50 N). Note weak poleward flow along the coastnorth of y-1273 km.
121
Distance off shore (km)
-1024.0 -853.3 -682.7 -512.0 -341.3 -170.7 a.0• . - .I I I.
010-
%
-
5
-- 3
S -453.1 -
76 5.•--
W * _'.1
14- 90. 3-. III
-1024.0 -853.3 -682.7 -512.0 -341.3 -170 7 .0
North-SouLh velocity at model day 546.0
Figure 4.61 Experiment 6: Cross-section at y-704 km(41.250 N) of the meridional component of velocity at day546 (yd 180). Dashed lines indicate equatorward flow, whilesolid lines indicate poleward flow. Note existence ofpoleward undercurrent.
122
Distance off shore (kin)
-1924.0 -653.3 -682.7 -512.9 -341.3 -17N.7 0.0
1 173 .3 -
g398.7-
W,1.
0
In
0rd
S461).3 --
i-IP
1°.,.,
Temperature contour at model day 456.0
Figure 4.62 Experiment 6: Surface temperature at day 456(yd 90). The contour interval is 10 C. The temperaturedecreases towards the coast. Note start of upwelling.
123
Distance off shore (kin)
-1024.0 -853.3 -682.7 -512.0 -341.3 -175.7 6.6
1460..- t -t
1173.3-
938. 7-I -
14
0)
to
00 1
0(d•
1.2
114734 .7-
Temperature contour at model day 576.0
Figure 4.63 Experiment 6: Surface temperature at day 576(yd 210). The contour interval is 10 C. The temperaturedecreases towards the coast. Note maximum extent ofupwelling.
124
Distance off shore (kin)
[email protected] -853.3 -682.7 -512.. -341.3 -1 7. 7 1.1
14 M ). I ! I I a M
1171.3-
18
Q.18. 7 -
0704.0-
0
Is)
V3
4 '• - 1 ' I234.7 2814
16 i
Temperature contour at model day 666.0
Figure 4.64 Experiment 6: Surface temperature at day 666(yd 300). The contour interval is 1 C. The temperaturedecreases towards the coast. Note occurrence of filament aty-250 km.
125
Kinetic Energy vs. Time
160 -T--r--T--r---T-T -7 1 1 ' 1 v Y I I I ' I T -,r--T -
1405
1315
1205
N 111
U
F0
90
C" 115 -•
60
50
0 50 Ion 150 200 250 300 351 41
Time (days?
Figure 4.65 Experiment 6: Total kinetic energy per unitmass time series for 1984 over the entire domain (Units ofthe kinetic energy are cm2 s8 2 ). Quasi-steady periods: days576-591 (yd 210-225), 606-624 (yd 240-258), and 645-657 (yd279-291).
126
Kinetic Energy vs. Time170T ' '
S145Nw
U -
* 1/10
S135U
w'y 13•
125
119
7uge Iday~l
Figure 4.66 Experiment 7: Total kinetic energy per tinitmass time series for Climo III over the entire Jomain (Unitsof the kinetic energy are cm2 sg 2 ). Peak value of 166 cm2 s" 2
at day 915 (yd 185).
127
Kinelic Energy vs. Time190 -- -j I ' I I , I I I , I I I I p I I I I I I I I I ' - - - -
135
w 130N
105
US
(V 125N
EU
Iw~ 120 -
115-
110 -
10 5 -
WOO t I i I I ! I I l I I I I I I t I i t i I I I i I I I I ' i I I _ _I_
0 50 100 150 200 250 300 3:;S 109
Time (days)
Figure 4.67 Experiment 7: Total kinetic energy per unitmass time series fcr Climo IV over the entire domain (Unitsof the kinetic energy are cm2 8' 2 ). Peak value of 145 cm2 s" 2
at day 1293 (yd 198).
128
Total Kinetic Energy180-II
100 - - clihno,.cllno2
*. . climo3 I •
140 *. cnmoq ,p
I 4 91400
-120 '"<*
0 100-E
80-'U
/
40-
20-0
0 250 500 750 1000 1250 1500Time (day)
Figure 4.68 Experiment 7: Total kinetic energy per unitmass time series for Climo, Climo II, Climo III, and ClimoIV over the entire domain (Units of the kinetic energy arecm 2 9-2).
129
Kinetic Energy vs. Time1 1 0 1-r - - - T -- - , 1 1 1 1 V w V I I I I '-T '- - V ! r ' - I - "
125
119
u 110•U105
w
N
Y
95
9(
50 100 11W 200 251 305 350 41-IF
Time Idays)
Figure 4.69 Experiment 8: Total kinetic energy per unitmass time series for 1983 over the entire domain (Units ofthe kinetic energy are cm2s"21 . Peak value of 128 CM28-2 atday 963 (yd 233).
130
85 ~ I II II ,i I I i I I I I L......I.L..LL...L.11 g....
Kinetic Energy vs. Time2•• -•-i v i ! , , I v , i r r T-y-l--1T--r T- - r v I- v-
-' -- -
- 170(VN
US160•
:
EU
wsY 149 -
110
1 -
90 _- 1 t I m ! I f I I t , I , , ,L.IJJ.LLI .tlJ l t
0 50 199 159 200 259 300 19 400
Time (daysl
Figure 4.70 Experiment 8: Total kinetic energy per unitmass time series for 1984 over the entire domain (Units ofthe kinetic energy are cm2 9,2). Peak value of 215 cm2 s" 2 atday 1368 (yd 273).
131
Total Kinetic EnergyI I I
- - monthly 81
2001 monthly 82
monthly 83
i.... onthly 8.,
S15o-U)
S- -
EI I°
I00-- "| ... -
I50- ,
0!
0 250 500 750 1000 1250 1500Time (dav)
Figure 4.71 Experirent 8: Total kinetic energy per unitmass time series for 1981, 1982, 1983, and 1984 over theentire domain (Units of the kinetic energy are cm2 s' 2 ).
132
V. SUOUARY AND RZCOIEDATIONS
A. SUMMARY
The different experiment runs are summarized in Tables
4.2, 4.4, and 4.5. In all first year runs (see Table 4.2),
both a surface equatorward current and a poleward
undercurrent developed. There was also a poleward coastal
surface current present during the winter season. Upwelling
was a seasonal feature which, as expected, had the coolest
temperatures during a non-El Nifto year (1981) and warmest
temperatures during an El Nifto year (1983). Both meanders
and eddies were generated. The eddies were cold core,
cyclonic, and had a size around the Rossby radius of
dsformation (30 km). Along with an equatorward surface
current, both meanders and eddies remained at the end of
each year. Instability analyses revealed that both
barotropic and baLoclinic processes were important eddy
generation mechanisms. In all first year runs, no filaments
were observed.
The follow-on (second year) model runs are sunmarized in
Table 4.4. In general, a weak coastal poleward surface
current was evident during the winter season in the northern
region of the domain for all years (Climo II, 1982 and
1984). A meandering equatorward surface current, already
133
present, at the start of these experiments was maintained.
A poleward undercurrent was generated in all experiments.
The eddies, already present at the start of the experiments,
were both cold core, cyclonic, and warm core, anticyclonic
eddies in Climo II and 1982, while in 1984 there were only
cold core, cyclonic eddies. The size and offshore extent of
the eddies were consistent with the first experimental runs.
Seasonal upwelling occurred with minimum temperatures of
-120 C for Climo II and 1982, and of -100 C for 1984. The
year 1984 had the largest extent of cool upwelled water as
expected for a year with the strongest equatorward winds.
Filaments developed in all three experiments, but was most
pronounced (as expected) in 1984. The filaments had an
offshore extent between 200 and 350 km. Instability
analyses revealed that both barotropic and baroclinic
processes were involved in eddy generation.
The last two years of the extended (four year) runs are
summarized in Table 4.5. Listed here are Climo IV, 1983,
and 1984. Similar results are obtained: A poleward coastal
surface current, a surface equatorward current, a poleward
undercurrent, along with embedded meanders and eddies. Of
interest, upwelling occurs later in 1983 (at yd 150) than
for the other years (yd 60 to yd 90). Although the minimum
temperature is the same (11.00 C) for all years, 1984
experienced a larger area of cooler water (all along the
coast) than that of the El Niflo (1983) year. In all
134
experiments, there were both cold and warm core eddies.
Finally, filaments were observed during Climo IV and 1984,
but not during 1983.
Experiments 1 through 6 investigated the formation or
generation of features such as currents, meanders, eddies,
and filaments. In Experiments 7 and 8 a quasi-steady
equilibrium state for the CCS was reached and the features
observed to develop in previous years were maintained.
Figure 5.1 plots the mean, eddy, and total kinetic
energy per unit mass for Climo, 1981, and 1983 (Experiments
1 - 3) together. During these first generation years,
Figure 5.1a shows 1981 had the most total kinetic energy and
1983 (El Nifto year) the least. This also holds true for
both the mean and eddy kinetic energy per unit mass plots
(Figures 5.1b and 5.1c). The decrease in kinetic energy
(total and mean) during the last few days of 1983 is not an
error, but rather an adjustment for continuation with the
start of the 1984 kinetic energy plots.
Figure 5.2 plots the mean, eddy, and total kinetic
energy per unit mass for Climo II, 1982, and 1984
(Experiments 4 - 6) together (the second years of
generation). The largest values of total, mean, and eddy
kinetic energy were observed during 1984 (Figure 5.2a
through 5.2c). Climo II had the least total and eddy
kinetic energy (Figures 5.2a and 5.2c), but both Climo II
135
and 1982 had nearly identical low mean kinetk• energy
(Figure 5.2b).
In all experiments, the atmospheric pressure cycle and
subsequent movement of low and high pressure patterns
affected the wind orientation and strength over the model
domain. The surface current was observed to respond to the
prevailing wind direction. As the wind turned equatorward
and exerted stress on the water surface, Ekman transport
offshore resulted in the upwelling of cooler water along the
coast. Interannual variability was thus observed as
expected.
In conclusion, the experiments showed that, due to the
wind forcing, features such as currents, meanders, eddies
and filaments could be generated and maintained. These
results support the hypothesis that wind forcing is a very
important mechanism for the generation of many of the
observed features in the CCS.
B. COMPARISON WITH OBSERVATIONS DURING AN EL N10 YEAR
It has been shown that the model results qualitatively
agree with available observations of the CCS during non-El
Nifo years. For example, the simulated surface and
subsurface currents, along with eddies and filaments agree
in size and magnitude with available observations of the
CCS, as listed in Batteen r& al. (1989).
136
Here the focus is shifted to comparisons of observed and
model results during an El Nifto year. Qualitative results
from both of the El Niflo experiments (3 and 8) along with
some observations taken in the CCS during the 1983 El Nifio
are presented in Table 5.1. Because the model does not
include remote forcing, the oceanic teleconnection will not
be expressed in the model results. There is still good
agreement between the model and observations taken during
the 1983 El Nifuo within the model domain. In particular,
warmer sea surface temperatures along with onshore advection
are evident, especially during the first three months of the
year. Poleward surface flow (for example Figure 5.3) is
enhanced and the entire current system appears weaker than
in the other model years. Based on these results, it is
concluded that atmospheric forcing played a substantial role
in the anomalous conditions observed in the CCS during the
El Nifto of 1983.
C. NAVAL RELEVANCE
As the Navy focus has recently shifted from blue water
to the littoral, EBC models such as the one used here take
on an increased importance. Although this EBC model would
require a finer scale before it could be used to predict the
location of features of interest, it is a start in the right
direction.
137
Accurately predicting the location of meanders, eddies
and regions of upwelling becomes critical for the successful
use of mines, along with aviation, amphibious, and covert
swimmer operations. The meanders and eddies could impact
several aspects of mining (i.e., laying, known position, and
mine removal). Smaller amphibious craft could get swept off
course if caught up in a strong jet associated with a
meander. The cold upwelled water may be nutrient rich and
support a plankton bloom which could significantly reduce
visibility in the water. In addition, the colder water
adversely affects swimmer immersion times.
Fog often results in upwelling regions where warmer air
is present over the cooler upwelled water. The effect of
this fog is to reduce surface visibility, which could be a
plus (such as to provide cover for an amphibious landing) or
minus (such as when defending an area against covert
operations). This decreased visibility may also affect
aviation operations by requiring instrument flight rules
(IFR) vice visual flight rules (VFR). Finally, other
optical and infrared devices will be degraded by the
presence of increased moisture in the atmosphere (i.e.,
fog).
D. RECON MTDATIONS
Future studies should let the model run for multiple
years, to allow for spin-up. As seen in multiple year
138
kinetic energy per unit mass time series plots, it appears
that spin-up may take only three to four years, but this
needs to be confirmed. Additional studies should use daily
rather than monthly winds to examine the effects of events
and relaxations. The incorporation of bottom topography and
a more realistic coastline would allow preferred eddy
generation areas to be identified. The incorporation of
bottom topography could also lead to an even better
depiction of the undercurrent, which plays an important role
in eddy generation. Finally, finer horizontal and vertical
resolution should be incorporated into the model to aid in
more accurately predicting the location of meanders, eddies,
and filaments.
139
TABLE 5.1 COMPARISON OF OBSERVED AND MODEL RESULTS DURINGAN EL NINO YEAR (1983).
El Niuo (1983) observations Experiment 3 Experiment 8in CCS compared to mean (1983 cold (1983 extended
restart) run)
Warmer SST Simulated Simulated(1, 2, 3)
Weaker overall current Simulated Simulatedsystem(2)
Enhanced poleward flow Simulated Simulated(2, 3)
Enhanced onshore advection Simulated Simulated(1, 2, 3)
Maximum equatorward surface Simulated Simulatedcurrent farther offshore(2)
References: (1) Rienecker and Mooers (1986)(2) Simpson (1983)(3) Simpson (1984)
140
Total Kinetic Energy100- I
---- clino11.. 1monhly 81
0- ..... mo lly (cold) I / - "
- -I N "
U)6 0 - . - .
C.)E 4U .0 o/ *
20 "I""
-- / /
I /
/ .
/ I
20- . •
2 18
Time(day
Figre5.l Epermets1-3 Ttalkietc eery pr ni
oeurte entir doperient (Unit Tofthe kinetic energy arerul
cn2s"2)o
141
Mean Kinetic Energy100- I I I -
- morthly 81
80- monthly 83 (cold)
S60-
Em 40-
L\.
20-
. . . •
0- 1..0 60 120 180 240 300 360
Time (day)
Figure 5.1b Experiments 1-3: Mean kinetic energy per unitmass time series for climatology (1980-1989), 1981, and 1983over the entire domain (Units of the kinetic energy arecm2s -2).
142
Eddy Kinetic Energy100- t n
7 climo 81 1moithly 83 (cold)
80 _
.n 60-
</E
40- - --
/ .
20-0 6/ / 2
/ ./ / .;
/ / .
/7
. .. * . .- .
0 60 120 180 240 300 360Time (day)
Figure 5.1c Experiments 1-3: Eddy kinetic energy per unitmass time series for climatology (1980-1989), 1981, and 1983over the entire domain (Units of the kinetic energy arecm2 s- 2).
143
Total Kinetic Energy200- I I P
- - climo 2S- montily 82
• * • monthly 84 (icold)
150-."*•
S100- - -
50-
//
S- . * * --'•k /
*,
50-
0- 5 I 5 3 I I
300 360 420 480 540 600 660 720Time (dav)
Figure 5.2a Experiments 4-6: Total kinetic energy per unitmass time series for Climo II, 1981, and 1983 over theentire domain (Units of the kinetic energy are cm2 s' 2 ).
144
Mean Kinetic Energy200 n n n I
- climo 2
*.-.-.montlby 82
imonthly 84 (rcold)
150-
U)
E 100-0It'
v*
,.,, .. .. •.
0- I l I I I T T
300 360 420 480 540 600 660 720Time (dav)
Figure 5.21b Experiments 4-6: Mean kinetic energy per unitmass time series for Climo II, 1981, and 1983 over theentire domain (Units of the kinetic energy are cm2 s8 2 ).
145
Eddy Kinetic Energy200- I I
- - climo 2
*.... monthly 82
***moilthly 84 (rcold)
150-
iS , 6,
< 10
10 - ' "'- . . .
Iii
50 " -
300 360 420 480 540 600 660 720Time (dav)
Figure 5.2c Experiments 4-6: Eddy kinetic energy per unitmass time series for Climo II, 1981, and 1983 over theentire domain (Units of the kinetic energy are cm2 s' 2 ).
146
Distance off shore (kTi)
-1,24.0 -653.3 -662.7 -512.3 -341.3 -17f.7 3.3
14 60. - 1 AI I I I
0
1173.3- Li
0
93H. 7 -
A 704.1-In
.-. 14
S7@4 . 7 ---
In.
North-South vel contour at model day 45.0
Figure 5.3 Experiment 3: Surface meridional, component ofvelocity at day 45. The contour interval is 1 cm s-. Thedashed lines indicate equatorward velocities. Latitudinalalongshore distance 0 (1408) km corresponds to 350 N (47.50N). Note enhanced poleward flow.
147
148
APPUEDIX A. INSTABILITIES FOR ZXPERIMENT 1 (CLIMO)
This appendix contains additional analyses from
Experiment 1 (climatological year) for the periods when the
total kinetic energy per unit mass became quasi-steady.
Energy transfer plots which consist of barotropic (mean
kinetic energy to eddy kinetic energy) and baroclinic (eddy
potential energy to eddy kinetic energy) were produced for
the following model days: 207 - 216, 228 - 231, and 297 -
303. These plots appear as Figures A.1 through A.6.
149
Distance off shore (kin)
-I 24.8 -853.3 -682.7 -512.A -341.3 -178.7 N.A
1171 3 -
93f8. 7 -
w1..
0"1:1• 704.P@- te. -
734.7-
Mean kinetic energy to eddy kinetic energy
avernge over model days 207.0 to 216.0
Figure A.1 Experiment 1: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) forclimatological (1980-1989) year, for model days 207 to 216.The contour interval is 1 ergs cm"3 8-1.
150
Distance off shore (kin)
-1124.0 -5,31.3 -687.7 -512.0 -341.3 -178.7 0.8
140)" 8- - - L - -- I I I I V -TIM.", na.tt I 92
TIS.7-
"to
Tlfl. 7 -/ -
a)L |LU,.L
0
0 0
,41
"Fin."(
192.81
234.7 -
Eddy potential energy to eddy kinetic energyaverage over model days 207.0 to 216.0
Figure A.2 Experiment 1: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for climatological (1980-1989) year, for model days 207 to216. The contour interval is 1 ergs cm- 3 s"1.
151
Distance off shore (kin)
-182A.8 -M53.1 -682.7 -5123. -341.3 -173.7 3.914Rnfl . - L - I I I I -
1173,. -
7AA. 7 -
0 J• 794 f.• -- "o
.' 469.3 -In
;,34.7 -
Menn kinetic energy to eddy kinetic energy
average over model days 228.0 to 231.0
Figure A.3 Experiment 1: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) forclimatological (1980-1989) year, for model days 228 to 231.The contour interval is 1 ergs cm" 3 a- .
152
D)istance off shore (kin)
-1124.0 -953., -682.7 -512.8 -341.3 -176.7 U.8
140n 0- I I II
l ife"ioIIIL'..
11 73.3 -
q3O. 7 - 1119.0
___ H ..,,
0"4 Me. 0 - °-
i~0
734.7--
ov~f
U hteII, .- , l°
r-a.7 - '-
Eddy potential energy to eddy kinetic energyaverage over model days 228.0 to 231.0
Figure A.4 Experiment 1: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for climatological (1980-1989) year, for model days 228 to231. The contour interval is 1 ergo cm" 3 s81
153
Distance off shore (kin)
-1•24.3 .853.3 -692.7 -512.3 -341.3 -170.7 N."
1409.0.- I I i I
1173.3-.
918.7--
I-. II ,.0
,d
4 469,.3---
234.7-
" .11- 1 1 1 1 IT - - -
Mean kinetic energy to eddy kinetic enerRy
average over model days 297.0 to 303.0
Figure A.5 Experiment 1: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) forclimatological (1980-1989) year, for model days 297 to 303.The contour interval is 1 ergo 6m"3 s" 1
154
n ~~~~~~Ig t]I f II.neI I..
Distanc off shore (kin)
-1•24.3 -853,. -682.7 -512.3 -341.3 -17N.7 3.3,43fl *- I I I -
91nn7 tin,1" '
ll,".,j l.
00
.- 704.0--&n
00
234. 7 - -
0. p
Eddy potential energy to eddy kinetic energyaverage over model days 297.0 to 303.0
Figure A.6 Experiment 1: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for climatological (1980-1989) year, for model days 297 to303. The contour interval is 1 ergs cm" 3 s".
155
156
APPEDIIX B. INSTABILITIES FOR EXPERIMEIT 2 (1981)
This appendix contains additional analyses from
Experiment 2 (1981) for the periods when the total kinetic
energy per unit mass became quasi-steady. Energy transfer
plots which consist of barotropic (mean kinetic energy to
eddy kinetic energy) and baroclinic (eddy potential energy
to eddy kinetic energy) were produced for the following
model days: 210 - 222, 240 - 252, 297 - 303, and 309 - 333.
These plots appear as Figures B.l through B.8.
157
Distance off shore (kin)
-1024.6 -853.3 -662.7 -512.0 -341.3 -176.7 0.0
1406 6 I I
1173.3-
11,m*,
930I. 7 -
I1• Ham.,
0. 74.-- 704 0-
0
IdU
234.7-
14,5..,
0.0- I I I I
Mean kinetic energy to eddy kinetic energy
average over model days 210.0 to 222,0
Figure B.1 Experiment 2: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1981,for model days 210 to 222. The contour interval is 10 ergscm 3 s-
158
Distance off shore (kin)
-1024.0 -853.3 -682.7 -512.9 -341.3 -173.7 R.8
14"R.U- I I I
1173.3 H477.
31173.3 - L141.2 H,,,.4
11141.3LI41r,1A
0)
|,1.4.•
-0
746.3-
0te
CC
€15
--- 411,,.,
030
234.7 -lo
I'1II.S "
11,,... 411141.0
Figure 82 Experiment 2: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1981, for model days 210 to 222. The contour intervalis 10 ergs cm 3 s-.
159
Distance off shore (kin)
--1924.0 -853.3 -682.7 -512.8 -341.3 -171.7 0. P
140988- I I I
an'r
1173.3-
18 .7-
SH..,
I-0 WIi.,.Q
0
- 3
..J 4 ,9.3- • -.
•734.7 - Lee.5
cm 8.
160*
Mean kinetic energy to eddy kinetic energy
average over model days 240.0 to 252.0
Figure 3.3 Experiment 2: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1981,for model days 240 to 252. The contour interval is 10 ergs
-m3 -1
160
Distance off shore (kin)
-124.3 -85•. 3 -682.7 -512.0 -341 .3 -173.7 3.31431.13- IL... I I I
1401 .0 -- 1 11 1".
l'161.3LIN.@3 11".
1173. 3-
93S. 7 -
• g76 7 4. 0J
SI|IIW~il |Wt
734.3-
04
ill.'llt~ •
U 0
234.7 7I
Eddy potential energy to eddy kinetic energyaverage over model days 240.0 to 252.0
Figure B.4 Experiment 2: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1981, for model days 240 to 252. The contour intervalis 10 ergs cm- 3 s"1.
161
D~istance off shore (km)
-1824 0 -953.3 -682.7 -512.0 -341.3 -1 7 7 6.R
14• •. - I I J____ __
1173.3-
q•3.7- L3-
S..
0-~ 704.0-
6Ti
21 4.7- -1
m
7>34.7 -Ilwss
Mean kinetic energy to eddy kinetic energyaverage over model days 297.0 to 303.0
Figure B.5 Experiment 2: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1981,for model days 297 to 303. The contour interval is 10 ergscm 3 1
162
Distance off shore (kin)
- 1024.1P -853.3 -682.7 -512. -341.3 -171.7 9.I140F1. 0 - -
1173.3-
938.7 -
0 .0 3 7040
&1I-o Ii.,,
0
C"
4j- 469.3--
4723.4 .7 --
0.0.tie.,,-
6.6-
Eddy potential energy to eddy kinetic energyaverage over model days 297.0 to 303.0
Figure B.6 Experiment 2: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1981, for model days 297 to 303. The contour intervalis 10 ergs cm" 3 s"1.
163
Distance off shore (kin)
-1924.0 -851.3 -682.7 -512.0 -341.3 -170.7 P.R, • .-I I I I -
1171.3-
9n 7F1
0
S469.3--
0
Mean kinetic energy to eddy kinetic energy
average over model days 309.0 to 33.1.0
Figure B.7 Experiment 2: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1981,for model days 309 to 333. The contour interval is 10 ergs
cm3 s-1
164
Distance off shore (km),124.9 -851.3 -682.7 -512.3 -341.3 -170.7 3.0
143113- 0 I ! I L _
1173.3-
131.7.
__
0)
7 74.0-
0
.' 469.3-
214f~. 7 --
Q0.7-
Illl, 14.
Eddy potential energy to eddy kinetic energyaverORe over model days 309.0 to 333.0
Figure S.8 Experiment 2: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1981, for model days 309 to 333. The contour intervalis 10 ergs cm3 s-.
165
166
APPENDIX C. INSTABILITIES FOR ZXPZRIMT 3 (1983)
This appendix contains additional analyses from
Experiment 3 (1983) for the periods when the total kinetic
energy per unit mass became quasi-steady. Energy transfer
plots which consist of barotropic (mean kinetic energy to
eddy kinetic energy) and baroclinic (eddy potential energy
to eddy kinetic energy) were produced for the following
model days: 186 - 192, 222 - 234, 249 - 258, 279 - 288, 312
- 315, 324 - 327, and 342 - 348. These plots appear as
Figures C.1 through C.14.
167
Distance off shore (kin)
-1fl24.0 -895.3 -6132.7 -512.s -3W1.3 -173.7 3.3
1 Fin 63 -
1173.3-
q3S. 7 -
0"".
0
oo
O,
-~469.3-
234.7-
U..- I I 1 1 I
Mean kinetic energy to eddy kinetic energyaverage over model days 188.0 to 192.0
Figure C.l Experiment 3: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1983,for model days 186 to 192. The contour interval is 10 ergscm 3 -
168
Distance off shore (kin)
-1•24.0 -353.3 -682.7 -512.9 -341.3 -17, 7 F."
14 09- - - l I I I I
1173.3-
fllsI.$
to°.. (i
"J t,.o~et',.o.
0. flls.@
J• 70 4 .0 - -
0
+ 469.3-
lltoofill""e,.g
-- II,,...
fIIl .4
Eddy potential energy to eddy kinetic energyaverage over model days 186.0 to 192.0
Figure C.2 Experiment 3: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1983, for model days 186 to 192. The contour intervalis 10 ergs cm 3 s-1
169
Distance off shore (km)
-1824.8 -853.3 -692.7 -S12.1 -341.3 -170 7 0.6,490.8- I I I I I
MI,
1173.3-
938,7 -
L.
to
0 G
4' 469.1-
S• 7 -- l I',.. .
234.7-
Mean kinetic energy to eddy kinetic energy
average over model days 222.0 to 234.0
Figure C.3 Experiment 3: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1983,for model days 222 to 234. The contour interval is 10 ergsC -3 9"I1
170
Distance off shore (km)
.1524.0 -853.3 -682.7 -512.6 -341 3 1711 7 1.4
1411 0 - _ -_ I -
~ ,, , tIe
lip 7
- tlat..
V Lowe a
0
S t",I. *U
7114 iP
0M
.aI IPMA• ,
Eddy potential energy to eddy kinetic energyaverage over model days 22.0 to 234 0
Figure CA4 Rxperitnent 3: Energy transfer@ of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1983, for weldays 222 to 234. The contour intervalis 10 erg. c"' @'I.
171
Distance off shore (km)
1,24 s -653 3 -66?.7 -S1?.6 -,"1 3 -179 7 66
1 400 a --- 11_ _-
4qa~ I
Mean kinti enrg to edd kieieeg
Now,
average ovrmdldy74. o28
S
a-3'
0-• 7t4 5-
0
S I I It .
cm
Mean kinetic energy to eddy kinetic energyaverage over model days 249.0 to 25860
Figure C.5 Experiment 3 : Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1983,for model days 249 to 258. The contour interval is 10 ergs
172
Distance off shore (kin)
1U74 of -F191 6•9S .7 -512 6 -341.3 170 7 a.1140nl 4 - - I---- 1.. - I - -_ -
1171 1
tin w
'lIR 7
0
-2 704-
0
H,..
"Lam 794 M
00
Eddy potential energy to eddy kinetic energyaverage over model days 249.0 to 258.0
Figure C.6 Experiment 3: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1983, for model days 249 to 259. The contour intervalis 10 ergs cm- 3 a--
173
Distance off shore (kin)
-11924. -853.3 -682.7 -512.0 -341 .3 -171.7 9.!
1409."-
173. --
q9if. 7 -
L..
0
7 0
0'4".
)I4. 7 -
@.* - I-!-
Mean kinetic energy lo eddy kinetic energy
average over model days 279.0 to 288.0
Figure C.7 Experiment 3: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1983,for model days 279 to 288. The contour interval is 10 ergsm-3 S-.
174
Distance off shore (kin)
-1024.0 -853.3 -68..7 -512.0 -341.3 -170.7 0.0140111- I I I I
1404..0
114444
1173.3'--
II444.
1II,4 4
q3r1.7 -
0
II 114.44
0-l= 794.9f -'44,•
0
114444 11444
I1
0(5
2 .7- H44 H..0
•4 11441441
Eddy potential energy to eddy kinetic energyaverage over model days 279.0 to 288.0
Figure C.8 Experiment 3: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1983, for model days 279 to 288. The contour intervalis 10 erg. cm"3 g"l.
175
Distance off shore (km)
-1824.,l -OC3,.3 -602.7 -512.g -341.3 -170,7 1.1
LIII.4?
173.3
-. ,i i 21 0* -
¶ 7 1 .
1 --
0 0
0*714.1K111.10 *0
+a 469 3 -. "Los-0 0-
o o.
*0
Mean kinetic energy to eddy kinetic energy
average over model days 312.0 to 315.0
Figure C.9 Experiment 3: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1983,for model days 312 to 315. The contour interval is 1 ergocm-3 8-1.
176
Distance off shore (kin)
-1024.0 -8•3.3 -602.7 -512.9 -341.3 -170.7 "l.al
14PS0 - I I I II I--V - _T _
fe*
NIL
r-->4 0 111
0
0.
387-
0 IT
". oe o d 30 t.
todd knt en in
for 1983, for model day. 312 to 315. The contour intervalis 1 erg. cm"3 u"I.
177
Distance off shore (kin)
-1324.3 -8953.3 -682.7 -512.3 -341.3 -1711.7 3."
140B(1.0- I I I
910. 7 18.0
A 7(14.0-
o t
a C
469.3-
CDto..'
1. - I "
Mean kinetic energy to eddy kinetic energy
average over model days 324.0 to 327.0
Figure C.11 Experiment 3: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1983,for model days 324 to 327. The contour interval is 1 ergsc-3 -1"
178
Distance off shore (kin)
-1024.8 -053.3 -682.7 -512.6 -341.3 -17F.7 9.91 .-I I I I _ _
1173.3 --
0
0) 0
164, - L, 00
a .00*Hm etC7
oo
aver.,e ove moe as340t 2.
179m
,0
)vr3eoermde.oy7- 0to370
Figure C.12 Experiment 3: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1983, for model days 324 to 327. The contour intervalis 1 ergs cn" 3 S"1
179
Distance off shore (kin)
-1824.0 -851.3 -682.7 -512.0 -341.3 -170.7 0.0
146R 8 i- _ I I I
1173.3-
|tW4,IS
93". 7-
C3
04 ll•7.4.0on
+a 469.3-
0
734 .7-'44.6. 7 -'*
Mean kinetic energy to eddy kinetic energyaverage over model days 342.0 to 348.0
Figure C.13 Experiment 3: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1983,for model days 342 to 348. The contour interval is 1 ergs
l-3 s-1"
180
Distance off shore (kin)
-1024.0 -853.3 -6f02.7 -512.0 -341.3 -170.7 0.0
140R 0- - _ _ _ _ _ __ _
list
6.40
1173.3-
36. 7 --
0
o
WIV
14*35,
0i!.. e
FEddy potential energy to eddy kinetic energy
average over model days 342.0 to 348.0
Figure C.14 Experiment 3: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1983, for model days 342 to 348. The contour intervalis 1 ergs cm" 3 s"1.
181
182
APPENDIX D. INSTABILITIES FOR ZXPERIENCT 4 (CLIKO I1)
This appendix contains additional analyses from
Experiment 4 (Climo II) for the periods when the total
kinetic energy per unit mass became quasi-steady. Energy
transfer plots which consist of barotropic (mean kinetic
energy to eddy kinetic energy) and baroclinic (eddy
potential energy to eddy kinetic energy) were produced for
the following model days: 378 - 408 (yd 12 - 42), 453 - 465
(yd 87 - 99), 504 - 516 (yd 138 - 150), and 624 - 636 (yd
258 - 270). These plots appear as Figures D.1 through D.8.
183
D~istance off shore (kim)
1924 P P%3 :i 6V 7 512 a -3.1 3i Ila 7 a 6
11 71 1
q3n. 7 -
L.~~ ~ C9 - _•3.
tim. 6
6,• .
0 711 .R -.
to
0
469.3- fiwe s
0
P34. 7 - 'lg.HNCN
Mean kinetic energy to eddy kinetic energyaverage over model days 378.0 to 408.0
Figure D.1 Experiment 4: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for ClimoII, for model days 378 to 408 (yd 12 - 42). The contourinterval is 1 ergs cm" 3 s"1.
184
Distance off Shorf, (kin)
tWP4 a h1451 1 611 7 417 34J 1 3 11 7 I7 Ia
'3 -- - J -
"10o 71lot III
foli-
um
ti0
'I
40
LooWII
0 04
Eddy potential energy to eddy kinetic energy
average over model days 376.0 to 406.0
Figure D.2 Experiment 4: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for Climo II, for model days 378 to 408 (yd 12 - 42). Thecontour interval is 1 ergs cm" 3 s0-.
185
iLptanee off shore (kin)
-61P . ! . . .. 7 -S I 1341 3 179 7 U.6
0~s---------L 1 L _ _ -L
9.11. 7 -q: i00
7194.7 -
0
+'469.3-
234.7 a-
I -. II • 1 -
Mean kinetic energy to eddy kinetic enrrgyaverage over model days 453.0 to 465 0
Figure D.3 Experiment 4: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for ClimoII, for model days 453 to 465 (yd 87 - 99). The contourinterval is 1 ergs cm" s3a.
186
Distance off shore (km)
-1I14. -893.3 -682.7 -517.8 -3AI .3 -17 W 7 1.1
14PO - L0 i 1 1. A- - -
Itng
'nft 7.'..' -- ma
_ •
0
1 79234.7--
-2
C,1
"i" '.
•'4 7 -- , U-
P. 11-O OLI
Eddy potential energy to eddy kinetic energyaverage over model days 453.0 to 465.0
Figure D.4 Experiment 4: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for Climo II, for model days 453 to 465 (yd 87 - 99). Thecontour interval is I ergs cm"3 s81.
187
D)istance off shore (km)
-102a.8 -RIS .3 -682.7 -512, -341.3 -171. 7 3.9
14PO 0 - - I-L J LL_.!
11 7:.:; -
111. 7 -
0)
I.I
70.3R.- "• -
X3 ' 0.
0
- °
234.7- -
0.9 02
Mean kinetic energy to eddy kinetic energyaverage over model days 504.0 to 516.0
Figure D.5 Experiment 4: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for ClimoII, for model days 504 to 516 (yd 138 - 150). The contourinterval is 1 ergs cm"3 s"I.
188
Distance off shore (km)
-1024.0 -953.1 -682.7 -512.3 -341.3 -176.7 R.'
I 4f - - _ _ 11 I - 1-
1171. 3
S1. 7..1-" 9 /1n. 7 - 139, 116 -
A 784.0-
0
46q. 3 -
'is..,
'34 7--• 0 -
0 .,0
3..- tu.nli..
Eddy potential energy to eddy kinetic energyaverage over model days 504.0 to 516.0
Figure D.6 Experiment 4: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for Climo II, for model days 504 to 516 (yd 138 - 150). Thecontour interval is 1 ergs cm" s- .
189
Distance off shore (km)
-1824.01 -815.3 -692.7 -512.0 -341.3 -1 73.7 3.3
140 - I Ia
0U
1173.3-
469. 7 -
°
l112
tin.,
It.,.. I,.,..
21•4.7 - ,
7-M.
Mean kinetic energy to eddy kinetic energynvernge over model days 624.0 to 636.0
Figure D.7 Experiment 4: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for ClimoII, for model days 624 to 636 (yd 258 - 270). The contourinterval is 1 ergs cm"3 a"1.
190
Distance off shore (kin)-1024.3 -953.3 -692.7 -512.1 -341.3 -178.7 8.9
14P1n. ... J I I I I
* IILI Hi
1173.3- Irk.
0
q36.7 - a
A .P I __
0
7fl4 .-- •flu."-
• -' 421 .7 -
C,>
Eddy potential energy to eddy kinetic energyaverage over model days 624.0 to 636.0
Figure D.8 Experiment 4: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for Climo II, for model days 624 to 636 (yd 258 -270). Thecontour interval is 1 ergo cm 3 s-.
191
192
APPZNDIX Z. INSTABILITIES OR EXPZRIMMIT 5 (1982)
This appendix contains additional analyses from
Experiment 5 (1982) for the periods when the total kinetic
energy per unit mass became quasi-steady. Energy transfer
plots which consist of barotropic (mean kinetic energy to
eddy kinetic energy) and baroclinic (eddy potential energy
to eddy kinetic energy) were produced for the following
model days: 507 - 516 (yd 141 - 150), and 525 - 528 (yd 159
- 162). These plots appear as Figures E.1 through E.4.
193
Distance off shore (kin)
-10124.0 -953.3 -682.7 -512.1 -341 .3 -170.7 N.91409~ 0- !I ___I__
I,,4*
1173.3 -j4.w
93fl. 7 -
00U,4
70 .0 1154." 0
00
C) 0
469.3- 344. 0
• 734. 7
6
a a
,,- . I 4. I-- .
Vo
Mean kinetic energy to eddy kinetic energyaverage over model days 507.0 to 516.0
Figure 3.1 Experiment 5: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1982,for model days 507 to 516 (yd 141 - 150). The contourinterval is 1 ergs cm"3 8" .
194
Distance off shore (km)
-11824.8 -853.3 -68,2.7 -512.I a -341.3 -170.7 7.8,140,8- I . I I I___I
1136.83
117.1 - q
938.7-
0 if-
I.. 'K
0In
to
0"
S469.3 -1353_
2_34.7 --
0 .
0.0- tI
Eddy potential energy to eddy kinetic energyaverage over mudel days 507.0 to 516.0
Figure 3.2 Experiment 5: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1982, for model days 507 to 516 (yd 141 - 150). Thecontour interval is 1 ergs cm- 3 s"-.
195
Distance off shore (km)
[email protected] -953.3 -682.7 -512.0 -341.3 -173.7 P.0
140.0-1 I 1
I'.,,
1173.3-
93n. 7 -
0 •
I1.0
0
0
-• ,169.3-
z)0
Mean kinetic energy to eddy kinetic energy
average over model days 525.0 to 528.0
Figure R.3 Experiment 5: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1982,for model days 525 to 528 (yd 159 - 162). The contourinterval is 1 ergs cm"3 a"1.
196
9.3- I I
Distance off shore (km)-11N24. -953.3 -682.7 -512.1 -341.3 -176.7 01.6
1410.1- I I ! I
1173.3-
9383.7-
0 .V
14U, " - ,?"''-
0 ,-- . V 0" - .t°. , 6 "*
""0
0 I,, 46g.3- ::J J i ! - " -'.
m•_
214.7-
o~V.
evernge over model days 525.0 to 526.0
Figure 3.4 Experiment 5: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1982, for model days 525 to 528 (yd 159 - 162). Thecontour interval is 1 ergs cm-3 s-.
197
198
APPENDIX F. INSTABILITIES FOR ZXPERIMENT 6 (1984)
This appendix contains additional analyses from
Experiment 6 (1984) for the periods when the total kinetic
energy per unit mass became quasi-steady. Energy transfer
plots which consist of barotropic (mean kinetic energy to
eddy kinetic energy) and baroclinic (eddy potential energy
tc eddy kinetic energy) were produced for the following
model days: 576 - 591 (yd 210 - 225), 606 - 624 (yd 240 -
258), and 645 - 657 (yd 279 - 291). These plots appear as
Figures F.1 through F.6.
199
Distance off shore (kin)
-1•24.9 -953.3 -682.7 -S12.9 -341.3 -17N.7 N.@
14011.9-
1173.3-
q3R .7 -
'.X
0
934
Mean kinetic energy to eddy kinetic energyaverage over mnodel days 576.0 to 591 0
Figure 1.1 Experiment 6: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1984,for model days 576 to 591 (yd 210 - 225). The contourinterval is 10 ergs cm 3 *r.
200
Distance off shore (kin)
.,324.9 -853.31 -682.7 -512.3 -341.3 -170.7 I.'- I,..L.-I_____I-
HI.....
117,.3-
q3R.7 -
4)
LI .
0
-0 704 . 7 -
V}
,- 0
I M - II I
Eddy potential energy to eddy klnetic energ~yaverage over model deys 578.0 to 591.0
Figure F.2 Experiment 6: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1984, for model days 576 to 591 (yd 210 - 225). Thecontour interval is 10 ergs cm"3 s"1.
201
Distance off shore (km)
-124.1 -653.3 -682.7 -512.1 -341.3 -176.7 S.PIAPn's- I
.173. 3 - 144
936.7 -7
0)
• : 794.0-
bo0
- 4'd11M.4 14
469.3-
fl V
IN4., lsN., '0
23 . -1
,jA
Tim., •.
0.8- I I
Mean kinetic energy to eddy kinetic energyaverage over model days 606.0 to 624.0
Figure F.3 Experiment 6: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1984,for model days 606 to 624 (yd 240 - 258). The contourinterval is 10 ergs cm"3 S&r.
202
Distance off shore (kin)
-1•124.1 -9.53.3 -682.7 -S12.. -341 .3 -171.7 0.0
1468.8- I I I___1_1 -
11165.1 1-104.7 Inell .1 1ý9'.I
ll1M.8
1173.3-
'11Wtm [1a
91FIS 7 -
If,,
~llma
09 741.04-
0- I
IM
0.9
Edd pnl-4 .
203
'1rn.a .
Eddy potential energy to eddy kinetic energyaverage over model days 608.0 to 624.0
Figure P.4 Experiment 6: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1984, for model days 606 to 624 (yd 240 - 258). Thecontour interval is 10 erg. c- 3 s-1.
203
Distance off shore (kin)-1824.9 -853.3 -682.7 -512.3 -341.3 -173.7 .6
t148.t
1173.3-
93. 7-
0)
0
[1...,
N• 469•,.3 -
234.7 -
Mean kinetic energy to eddy kinetic energyavernge over model days 645.0 to 657.0
Figure F.5 Experiment 6: Energy transfers of mean to eddykinetic energy (i.e., barotropic energy transfer) for 1984,for model days 645 to 657 (yd 279 - 291). The contourinterval is 10 ergs cm"3 2r.
204
Distance off shore (km)
-1324.9 -153.3 -682.7 -512.3 -341.3 -173.7 3.9•4 9. .9 I I I I
I ! 7.!. 31-325 .
1173.3-
93"1. 7 -
0
A 704.0- _., -
°0m}• " 0
00
,14.7--0
Eddy potential energy to eddy kinetic energyaverage over model days 645.0 to 657.0
Figure F.6 Experiment 6: Energy transfers of eddy potentialto eddy kinetic energy (i.e., baroclinic energy transfer)for 1984, for model days 645 to 657 (yd 279 - 291). Thecontour interval is 10 ergs cm"3 8"1.
205
206
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Batteen, M.L., and Y.-J. Han, 1981: On the computationalnoise of finite-difference schemes used in ocean models.Tellus, 33, 387-396.
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Carton, J.A., 1984: Coastal circulation caused by anisolated storm. J. Phys. Oceanogr., 14, 114-124.
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Huyer, A., P.M. Kosro, S.J. Lentz, and R.C. Beardsley, 1989:Poleward flow in the California Current System. In,Poleward Flows Along Eastern Ocean Boundaries, S.J.Neshyba, C.N.K. Mooers, R.L. Smith and R.T. Barber,eds., Lecture Notes on Coastal and Estuarine Studies,Springer-Verlag, 142-159.
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210
INITIAL DISTRIBUTION LIST
No. Copies
1. Defense Technical Information Center 2Cameron StationAlexandria, VA 22304-6145
2. Librarian, Code 52 2Naval Postgraduate SchoolMonterey, CA 93943-5101
3. Chairman (Code OC/Bf) 1Department of OceanographyNaval Postgraduate SchoolMonterey, CA 93943-5122
4. Chairman (Code MR/Hy) 1Department of MeteorologyNaval Postgraduate SchoolMonterey, CA 93943-5114
5. Dr. Mary L. Batteen, (Code OC/Bv) 2Department of OceanographyNaval Postgraduate SchoolMonterey, CA 93943-5122
6. Dr. Curtis A. Collins, (Code OC/Co) 1Department of OceanographyNaval Postgraduate SchoolMonterey, CA 93943-5122
7. Dr. Leslie K. Rosenfeld (Code OC/Ro) 1Department of OceanographyNaval Postgraduate SchoolMonterey, CA 93943-5122
S. LT James Vann 212 Hedgerow PlaceJackson, TN 38305
9. Director, Naval Oceanography Division 1Naval Observatory34th and Massachusetts Ave, NWWashington, DC 20390
211
10. Conmander 1Naval Meteorology and Oceanography Command1020 Balch BoulevardStennis Space Center, MS 39529-5005
11. Commanding Officer 1Naval Oceanographic OfficeStennis Space Center, MS 39529-5000
12. Commanding OfficerFleet Numerical Meteorology and Oceanography Center 17 Grace Hopper Avenue, STOP 1Monterey, CA 93943-5001
212