Gulf of Alaska Climate and Oceanography. Pacific Decadal Oscillation positive phase negative phase tao.atmos.washington.edu/pdo/ Winter PDO score (November

Gulf of Alaska Climate and Oceanography

-3

-2

-1

0

1

2

1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000

PD

O In

de

x S

core

Pacific Decadal Oscillation

positive phase negative phase

tao.atmos.washington.edu/pdo/

Winter PDO score (November – March)

jisao.washington.edu/pdo/PDO.latest


Oceanographic correlates:

- Atmospheric pressure - Air / sea temperature

- Freshwater input - Surface salinity

- Mixed layer depth - Upwelling / downwelling strength

- Wind stress - Sea ice extent / time of thaw

- Nutrient flux - Current strength / gyre circulation

- Solar radiation absorption- Aerosol (dimethylsulfide) production

- Primary productivity - Secondary productivity


Effect on trophic level of Alaska’s commercial fishery landings 1964-2003

R2 = 0.32

3.6

3.7

3.8

-2 -1 0 1 2

PDO score (3-yr running mean, lagged 2 yr)

Me

an

tro

ph

ic le

vel o

f ca

tch

.


0

20

40

60

1997 1998 1999 2000 2001 2002 2003 2004 2005

Jou

rna

l art

icle

s

Mantua et al. 1997,

Minobe 1997

PDO journal articles listed in Web of Science

-3.0

-2.0

-1.0

0.0

1.0

2.0

1950 1960 1970 1980 1990 2000Vic

tori

a P

atte

rn s

core Principal component 2 - Victoria Pattern

(Bond et al. 2003. Geophys. Res. Let. 30:2183)

-3.0-2.0-1.00.01.02.03.0

1950 1960 1970 1980 1990 2000

PD

O s

co

re

Principal component 1 - Pacific Decadal Oscillation


-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

1970 1975 1980 1985 1990 1995 2000

STARS-definedcommunity states

(Rodionov. 2004. Geophys. Res. Let. 31:L09204)

Com

mun

ity s

tate

(N

MD

S a

xis1

)

P < 0.0001

P < 0.0001

P > 0.1

More groundfish

More capelin & shrimp

Catch composition of small-mesh trawls in three Alaska Peninsula Bays

July – October hauls; Chignik-Castle, Kuiukta, Pavlof Bays

-3

-2

-1

0

1

2

1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000

PD

O In

de

x S

core

Winter PDO score (November – March)

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1850 1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000

Running 5-yr mean

Tem

pera

ture

ano

mal

y re

lativ

e to

196

1-19

90 (

ºC)

Average global temperature

East Anglia University, UKwww.cru.uea.ac.uk/cru/data/temperature/#datdow


-1

-0.5

0

0.5

1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000

5-yr running mean

East Anglia University, UKwww.cru.uea.ac.uk/cru/data/temperature/#datdow

Tem

pera

ture

ano

mal

y re

lativ

e to

196

1-19

90 (

ºC)

Average North Pacific temperature

hour monthday year centurydecade millennium

Time scale of data collection

Overview: GOA Climate and Oceanography Posters

Early Holocene / Late Pleistocene Shoreline North of the Present Ice

Margin of the Bering Sea, A. Pasch & N. Foster

Nutrient Dynamics in the Gulf of Alaska, C. Mordy et al.

GEM Biophysical Observations Aboard the Alaskan State Ferries,

E. Cokelet et al.A Catalog of Marine Gap Winds for the

Western and Northern Gulf of Alaska, J. Curtis

& N. Bond Yakutat Eddies and Shelf/Slope Exchange in the Coastal Gulf of

Alaska, M. Janout et al.

Oceanographic Boundary Conditions to Cook Inlet,

W. Pegau et al.

A Catalog of Marine Gap Winds for the Western and Northern Gulf of Alaska

Joel Curtis and Nicholas Bond

Oceanographic Boundary Conditions to Cook Inlet

W. Scott Pegau, Edward Cokelet and Susan Saupe

Yakutat Eddies and Shelf/Slope Exchange in the Coastal Gulf of Alaska

Markus Janout, S. Okkonen, T. Weingartner, D. Musgrave, and T. Royer

surface salinity

sea surface height

bathymetry





GEM Biophysical Observations Aboard the Alaskan State Ferry Tustumena

Edward Cokelet, A. J. Jenkins, W. S. Pegau, C. W. Mordy, and M. Sullivan

GEM Biophysical Observations Aboard the Alaskan State Ferry Tustumena

Edward Cokelet, A. J. Jenkins, W. S. Pegau, C. W. Mordy, and M. Sullivan

Nutrient Dynamics in the Gulf of Alaska

Calvin Mordy, Peter Proctor, Sigrid Salo, Phyllis J. Stabeno, and David P. Wisegarver

Invertebrate Evidence for an Early Holocene / Late Pleistocene Shoreline North of the Present Ice Margin of the Bering Glacier

Anne D. Pasch and Nora R. Foster

Mike Litzow1 & Lorenzo Ciannelli21Alaska Fisheries Science Center, NOAA

Fisheries2Center for Ecological and Evolutionary Synthesis,

University of Oslo

Has Climate Change Produced Oscillating Ecosystem Control in the Gulf of Alaska?

Taxa involved in PDO-driven community reorganizations

Salmon ShrimpZooplankton Gadids

Flatfishes Capelin Jellyfish

Seabird / pinniped diets

Salmon AnchoviesZooplankton Sardines

Mackerel HakeRockfish Sablefish

Seabirds

Tuna

SardinesAnchovetaSeabirds

SardinesAnchovies

Zooplankton

Tuna

PDO regime shift and Gulf of Alaska cod abundance

0

200

400

600

800

1964 1974 1984 1994 2004

Estimated age 3+ biomass76/77

regime shift

103

met

ric

ton

sAverage of models 2 & 3, 2006 SAFE document

Cold regime1954 - 1975

Proportion of occurrence in NMFS bottom trawls

Warm regime1978 - 2005

Proportion of hauls with cod Proportion of hauls with cod

0.001

0.01

0.1

1

10

100

1000

1970 1975 1980 1985 1990 1995 2000 2005

CodPrey (4 shrimp spp. + capelin)

CP

UE

(k

g /

km t

ow

ed

)

Pavlof Bay small-mesh trawl data

July – October, n = 593 hauls

Cod exercise top-down control on shrimp populations in N. Atlantic

(Worm and Myers 2003. Ecology 84:162-173)

Cod-shrimp interactions

Cod regulation cascades to zooplankton, phytoplankton and nutrients

(Frank et al. 2005. Science 308:1621-1623)

Climate effects on cod-shrimp interactions

N. Pacific biological time series show non-linear dynamics / alternate stable states

(Hsieh et al. 2005. Nature 435:336-340)

Alternate stable states predict different ecological controls under different climate regimes – i.e., oscillating control

(Scheffer et al. 2001. Nature 413:591-596)

Oscillating control hypothesis:

Approach:

1) Cod-shrimp abundance correlations

negative correlation = top down controlpositive or weak correlation = bottom-up control

(Worm and Myers 2003. Ecology 84:162-173)

multi-modal distribution of controlling parametersnecessary condition of alternate states (Scheffer et al. 2001. Nature 413:591-596)

1970s climate regime shift resulted in change between bottom-up and top-down control in Gulf of

Alaska cod-shrimp system

Approach:

2) Non-additive modeling approach to test for different control under different climate regimes

(Cianelli et al. 2004. Ecology 85:3418-3427,Cianelli et al. 2005. Proc. R. Soc B 272:1735-1743)

Climate regulation of top-down and bottom-up ecosystem controlC

orre

latio

n st

reng

th

(run

ning

5-y

r P

ears

on’s

r)

Temperature index (PC1 score) -2 -1 0 1

-1.5

-1.0

-0.5

0.0

0.5

1.0

pc1mean

s(p

c1

me

an

,4.0

7)

1

0

-10 1-1-2

74

75

7677 78

79

80

82

8384

85868788

89

90

91

92

93

9495

9697

98

99

00

01

0203

81

Top-down control

Bottom-up control

Temperature effects on running 5-yr correlation between cod and standardized prey abundance (capelin and 4 shrimp species)

Model R2 = 0.42, P(temperature) = 0.005

0 10

Count

1) Correlation approach

Non-additive modeling approach

Selects between competing models:

Generalized Additive Model (GAM): response variable estimated by adding effects of smoothing functions for each explanatory variable

Nonadditive model: constructs separate GAMs for data below and above threshold value in some environmental or biological parameter

Choice of additive or non-additive model, and selection of threshold value, made by minimizing # of parameters and maximizing model fit to data

-1.0 -0.5 0.0 0.5 1.0

-2.0

-1.0

0.0

1.0

log(meanprey + 1)

s(log(m

eanpre

y +

1),

1.2

2)

-2 -1 0 1 2

-2.0

-1.0

0.0

1.0

pc1

s(p

c1,1

)

0 2 4 6 8 10 12

-2.0

-1.0

0.0

1.0

logcodcatch

s(logcodcatc

h,1

)

0.0 0.5 1.0 1.5 2.0 2.5

-2.0

-1.0

0.0

1.0

laggedcod

s(laggedcod,2

.31)

Prey abundance index

P = 0.01

-1.0 -0.5 0.0 0.5 1.0

-2.0

-1.0

0.0

1.0

log(meanprey + 1)

s(lo

g(m

eanp

rey

+ 1

),1.

22)

-2 -1 0 1 2

-2.0

-1.0

0.0

1.0

pc1

s(pc

1,1)

0 2 4 6 8 10 12

-2.0

-1.0

0.0

1.0

logcodcatch

s(lo

gcod

catc

h,1)

0.0 0.5 1.0 1.5 2.0 2.5

-2.0

-1.0

0.0

1.0

laggedcod

s(la

gged

cod,

2.31

)

Temperature index (PC1 score)

P = 0.03

Eff

ect

on

co

d a

bu

nd

ance

-1.0 -0.5 0.0 0.5 1.0

-2.0

-1.0

0.0

1.0

log(meanprey + 1)

s(lo

g(m

eanp

rey

+ 1

),1.

22)

-2 -1 0 1 2

-2.0

-1.0

0.0

1.0

pc1

s(pc

1,1)

0 2 4 6 8 10 12

-2.0

-1.0

0.0

1.0

logcodcatch

s(lo

gcod

catc

h,1)

0.0 0.5 1.0 1.5 2.0 2.5

-2.0

-1.0

0.0

1.0

laggedcod

s(la

gged

cod,

2.31

)

Log (cod CPUE) lag 1 yr

P < 0.001

Additive model of cod abundance

Model R2 = 0.74

2) Non-additive modeling approach

0.0 0.5 1.0 1.5 2.0 2.5

-0.5

0.0

0.5

1.0

Cod effect below threshold

cod

s(co

d,1)

-2 -1 0 1 2

-0.5

0.0

0.5

1.0

Temp effect above threshold

pc1

s(pc

1,1)

0.5 1.0 1.5 2.0 2.5

-0.5

0.0

0.5

1.0

Lagged shrimp effect

laggedpink

s(la

gged

pink

,1)

-0.20 -0.10 0.00 0.10

0.10

0.12

0.14

NMDS

GC

V

Log (cod CPUE)

Eff

ect

on

pin

k sh

rim

p a

bu

nd

ance

P = 0.003

Below threshold

0.0 0.5 1.0 1.5 2.0 2.5

-0.5

0.0

0.5

1.0

Cod effect below threshold

cod

s(co

d,1)

-2 -1 0 1 2

-0.5

0.0

0.5

1.0

Temp effect above threshold

pc1

s(pc

1,1)

0.5 1.0 1.5 2.0 2.5

-0.5

0.0

0.5

1.0

Lagged shrimp effect

laggedpink

s(la

gged

pink

,1)

-0.20 -0.10 0.00 0.10

0.10

0.12

0.14

NMDS

GC

V

Temperature (PC1 score)

Eff

ect

on

pin

k sh

rim

p a

bu

nd

ance

Above threshold

P = 0.08

Non-additive factors affecting pink shrimp abundance

-0.6

-0.4

-0.2

0

0.2

0.4

1970 1975 1980 1985 1990 1995 2000 2005

Co

mm

un

ity

stat

e (N

MD

S a

xis

1)

More shrimp & capelin

More groundfish

Threshold

Model R2 = 0.85

2) Non-additive modeling approach

Conclusions

1) Support for hypothesis that climate change has produced oscillating control in Gulf of Alaska – shifts between bottom-up and top-down control

- temperature regulation of top-down and bottom-up control of cod-shrimp interactions

- non-additive control of shrimp populations, depending on community state

2) Results demonstrate limitations in using annual-scale variability to study decadal-scale patterns in climate-ecosystem interactions

Acknowledgements

Paul Anderson, Dave Jackson, Alisa Abookire, Franz Mueter

and everyone who helped collect small-mesh trawl data through the years…

Documents

Gulf of Alaska Climate and Oceanography. Pacific Decadal Oscillation positive phase negative phase tao.atmos.washington.edu/pdo/ Winter PDO score (November