Jamie MorisonPolar Science Center

University of Washington

Seattle, Washington USA

morison@apl.washington.edu

SEARCH Update

ARCSS AHW Feb. 20, 2002

SEARCH The Arctic is in the midst of a major

change involving Atmosphere, Ocean, and Land.

Impacts on the ecosystem and society

The Arctic change is connected to changes in the atmospheric circulation of the Northern Hemisphere and global climate.

Future course is unknown

Requires long-term program of observations, analysis, modeling, integration and application to society’s response.

Unaami The complex of changes that have dominated the

Arctic in the last 2 decades

Unaami characterized by among other things:

- Drop in Arctic atmospheric pressure

- Increased SAT in N. Europe & Russian Arctic

- Cyclonic ocean circulation, rising coastal sea level

- Increased Atlantic water temperature

- Decreased ice cover

- Decreased Beaufort Sea salinity

From the Yup’ik word meaning tomorrow, synonymous with change for Arctic residents -transportation, food gathering, quality of life

The “El Nino of the North”

A Changing Arctic

SEARCH Strategy

A P P L I C A T I O N

Impacts on Ecosystem and Society

Data

O B S E R V A T I O N S

Long-term and Pan-Arctic

M O D E L I N G

Data Assimilation

Data

Understanding &Prediction

PROCESS STUDIES

UnderstandingSpecific Links

UnderstandingProcesses

Data & LogisticsOpportunities

SEARCH and Other Programs

CLIVARUnderstand

Climate Variation

SEARCH-CLIVARWorking Group

ACSYS/CLiCUnderstand Change in

Global Cryosphere

CliC-SEARCHMOA

Arctic Council(ACIA, AMAP....)

Protection of the ArcticEnvironment and Sustainable

Development

NSF -ARCSSUnderstand theArctic System

S E A R C HUnderstand

Response of theArctic System

Recent SEARCH Developments

Science Plan published Summer 2001: http://psc.apl.washington.edu/search/ index.html

IWG Completes 2003 Funding Implementation Framework and IARPC submits to OMB Sept 2001

SSC & IWG developing bridging Science Implementation Strategy:

A) Questions, Priorities, Organization B) Terms of Reference C) Implementation Plan Skeleton

Arctic and Sub-arctic Ocean Flux (ASOF) Workshop

Atmospheric and Cryospheric Change in the Arctic (ACCA) Workshop

First SEARCH AO : Arctic Freshwater Cycle: Land/Upper-

Ocean Linkages

SEARCH Tasks&

Modes of Variability

Outreach activities to educate about SEARCH

Refine implementation in areas such as: - Marine Ecosystem - Terrestrial Ecosystem - Arctic Ocean and Sea Ice - Societal Impacts and Application

Modes of variability are important to implementation:

Learning modes of variability helps our understanding of the system

Extreme modal response (Unaami) reveals internal dynamics

Key to intelligent sampling decisions

Ice andAtmospheric Pressure Changes

ICE THICKNESS DECREASED 42% in last 30 years

(Comparison of submarine data, Rothrock et al, 1999)

Transpolar Drift of ice shifted axis counterclockwise producing a more cyclonic motion in 1990s

Ice extent decreased 3% per decade

Beaufort High decreased and shifted east in 1990s

Surface Atmospheric Pressure (contours) and Ice Velocity (arrows)Averaged 1979-87 and 1988-96

Steele & Boyd (1998)

Connection to Global Climate

Low pressure spins up Polar Vortex, brings warm air to Greenland Sea and Russian Arctic

Warm air overGreenland Seaallows warmerAtlantic Water inArctic Ocean

Warm air advection- increases SAT- warms permafrost

Increase in Polar Vortex- More cyclonic ocean circulation- Shift in front and Transpolar Drift- Russian shelf water to Beaufort

Increase in Polar Vortex- Weakens Beaufort High- Increases open water- Decreases Albedo- Increases radiative heating & melt- Freshens upper Beaufort Sea

Cyclonic Circulation- Increases export of fresh water- Increases stratification in Greenland and Labrador seas- Inhibits global ocean overturning

AO Index

1900 1920 1940 1960 1980 20001900 1920 1940 1960 1980 2000

Rising AO means lowers atmospheric pressure over the Arctic.

Thompson and Wallace, 1998)

Ocean ChangesSalinity Difference, Pargo ‘93 - Climatology

Shift in front between Atlantic and Pacific waters

Salinity increase in the upper 200 m of the Makarov

Surface salinity decrease in Beaufort Sea (SHEBA)

Mendeleyev R.

Makarov B.

Alaska

Greenland

Siberia

0

500

Canada B.

Alpha R.

400

4 3

300

2

200

1

100

0-1-2-3

90°E

ΔS

75°N90°W

80°N

85°N

3000 m

1000 m2000 m

Eurasian B.

Lomono

Frontal Line1993

0°

180°

Frontal LinePre-1993

From Morison, J. H., K. Aagaard, and M. Steele, 2000, Recent Environmental Changes in the Arctic: A Review, Arctic, 53, 4.

Saltier Atlantic-Derived Water

Fresher Pacific-Derived Water

Frontal Shift

Salinity Increase

Pargo ‘93 - Climatology Early Indication of Change from ARC-

Instigated 1993 SCICEX

Appearance of warm cores over ridges

Increase in Temperature maximum of over 1.5°

Atlantic Water Temperature maximum is shallower

Mendeleyev R.

Makarov B.

0

500

Canada B.

Alpha R.

400

2.0

300

1.5

200

1.0

100

0.5

75°N

0.0

80°N

85°N

-0.5-1.0

90°E

ΔT(° )C

.Eurasian B

3000 m

1000 m2000 m

Lomono

Alaska

Greenland

Siberia

90°W

Frontal Line1993

Frontal LinePre-1993

0°

180°

From Morison, J. H., K. Aagaard, and M. Steele, 2000, Recent Environmental Changes in the Arctic: A Review, Arctic, 53, 4.

Atlantic Water 1.5° warmer

Modes of Variability Caveats

(from Brodeur et al., 1999)

Small perturbation in physical mode can create nonlinear change in other parts of the system (e.g., ecosystem):

Keep some broad sampling in the mix

Regime shifts likely involve the rise and combination of previously less interesting modes

Modes of Variability still provide a useful paradigm.