View
218
Download
1
Category
Tags:
Preview:
Citation preview
Lessons learned in C20C Lessons learned in C20C “Pacemaker” experiments“Pacemaker” experimentsLessons learned in C20C Lessons learned in C20C
“Pacemaker” experiments“Pacemaker” experiments
James L. Kinter James L. Kinter ⅢⅢ andand K. Emilia Jin K. Emilia Jin
Center for Ocean-Land-Atmosphere Studies, USACenter for Ocean-Land-Atmosphere Studies, USA
James L. Kinter James L. Kinter ⅢⅢ andand K. Emilia Jin K. Emilia Jin
Center for Ocean-Land-Atmosphere Studies, USACenter for Ocean-Land-Atmosphere Studies, USA
Workshop on Climate of the 20th Century & Seasonal and Interannual Climate PredictionWorkshop on Climate of the 20th Century & Seasonal and Interannual Climate PredictionWorkshop on Climate of the 20th Century & Seasonal and Interannual Climate PredictionWorkshop on Climate of the 20th Century & Seasonal and Interannual Climate Prediction
C20C pace-maker experimentsC20C pace-maker experiments
Region for prescribed SST
Mixed-layer depth
Climate drift and relaxation
Blending zone with observed SST: tropics and polar region
Management of sea ice
Experimental IssuesExperimental Issues
Ongoing Pace-maker experiments in COLAOngoing Pace-maker experiments in COLA
ExperimentBlending
Mixed-layer depth Extratropics Tropics statustropics Polar
region
Run 014 points
(10-15N,10-5S) 70-60S,50-60N
30 times 9-grid smoothed Levitus climatology
Slab ocean mixed-layer
Observed interannual
SST5 yr
Run 029 points
(10-20N,10-20S)70-60S,50-
60N30 times 9-grid smoothed Levitus climatology
Slab ocean mixed-layer
Observed interannual
SST5 yr
Run 035 points
(10-20N,10-20S)70-60S,60-
70N
Zonal mean monthly Levitus climatology exc
ept Eastern Pacific
Slab ocean mixed-layer
weak damping of 15W/m2/K
Observed interannual
SST3 yr
Run 04 No blending 70-60S,60-70N
Zonal mean monthly Levitus climatology exc
ept Eastern Pacific
Slab ocean mixed-layer
weak damping of 15W/m2/K
Observed interannual
SST3 yr
Run 05 No blending70-60S,60-
70N
Zonal mean annual mean climatology
except Eastern Pacific
Slab ocean mixed-layer
weak damping of 15W/m2/K
Observed interannual
SST0.5 yr
Experiments
AGCM NCEP operational Global Forecast System (GFS)
T62 64 Levels
1. Prescribed region as pace-maker1. Prescribed region as pace-maker
Shaded region denotes that Shaded region denotes that dynamic term prevails over thermodynamic termdynamic term prevails over thermodynamic term
in 20-yr NCEP CFS (Climate Forecast System) simulationin 20-yr NCEP CFS (Climate Forecast System) simulation
The NCEP Climate Forecast System (CFS)
AGCM Resolution OGCM Resolution
NCEP operational Global Forecast System (GFS) T62 64 Levels MOM 3.0 1oX1/3 to 1o 40 Levels
ynamicsmodtherdynamicsdt
dSST
HC
Flux
p
sfc
t
SSTSST nn
2
11
1. Prescribed region as pace-maker1. Prescribed region as pace-maker
Years showing that Years showing that dynamic term prevails over thermodynamic termdynamic term prevails over thermodynamic term
in 20-yr NCEP CFS (Climate Forecast System) simulationin 20-yr NCEP CFS (Climate Forecast System) simulation
(a) Annual mean
(b) JJA (c) DJF
2. Mixed-layer depth in slab ocean model2. Mixed-layer depth in slab ocean model
Prescribed mixed-layer depth:Prescribed mixed-layer depth:
30 time 9-grid smoothed mixed layer depth 30 time 9-grid smoothed mixed layer depth of Levitus climatologyof Levitus climatology
Simulated minus observed SSTSimulated minus observed SST
2. Mixed-layer depth in slab ocean model2. Mixed-layer depth in slab ocean model
Zonal mean mixed-layer depth for Levitus climatologyZonal mean mixed-layer depth for Levitus climatology
Each ocean basin Difference from Global mean
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
2. Mixed-layer depth in slab ocean model2. Mixed-layer depth in slab ocean model
Zonal mean mixed-layer depth for Levitus climatologyZonal mean mixed-layer depth for Levitus climatology
Each ocean basinEach ocean basin Difference from Global meanDifference from Global meanDifference from Global mean Difference from Global mean
except Eastern Pacificexcept Eastern Pacific
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Jan
Apr
Jul
Oct
Jan
Global mean except Eastern PacificGlobal mean
3. Climate drift and relaxation3. Climate drift and relaxation
Obs.with relaxation without relaxation
1949 1950 1951
1949 1950 1951
(a) Global mean SST except pace-maker region
(b) Simulated minus observed global mean SST difference
run 3 run 4
4. Blending zone with observed SST4. Blending zone with observed SST
5 points blending No blending
Ratio of observed SST
Cross section for 140W
Cross section for equator
1949 1950 1951
1949 1950 1951
4. Blending zone with observed SST4. Blending zone with observed SST
(a) Global mean SST except pace-maker region
(b) Simulated minus observed global mean SST difference
Obs.with blending without beldning
5. Sea ice / seasonality of mixed-layer depth5. Sea ice / seasonality of mixed-layer depth
Seasonal march of difference between simulated and observed SST over the North Pacific (100E-60W)
Seasonal march of mixed-layer depth
1949 1950 1951
1949 1950 1951
1949 1950 1951
1949 1950 1951
5. Sea ice / seasonality of mixed-layer depth5. Sea ice / seasonality of mixed-layer depth
Seasonal march of sea Ice fraction over the Pacific (120E-120W)
Seasonal march of difference between simulated and observed SST over the North Pacific (100E-60W)
5. Sea ice5. Sea ice
Seasonal mean sea ice fraction climatology
for 1950-1999 Hadley Center data
1949 1950 1951
1949 1950 1951
5. Sea ice / seasonality of mixed-layer depth5. Sea ice / seasonality of mixed-layer depth
(a) Global mean SST except pace-maker region
(b) Simulated minus observed global mean SST difference
Obseved global mean (0-360E, 60S-60N)Simulated global meanObserved North Pacific (100E-60W, 20-60N)Simulated North Pacific
Recommended