A Major Climate/Ecosystem Shift Observed in the Northern Bering Sea James E. Overland1, Jacqueline M. Grebmeier2, Sue E. Moore3, Ed V. Farley4, Eddy C. Carmack5, L.W. Cooper2, K E. Frey.6, J.H, Helle4, F.A. McLaughlin5, S. Lyn McNutt7, Phyllis

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A Major Climate/Ecosystem Shift Observed in the
Northern Bering Sea James E. Overland1,
Jacqueline M. Grebmeier2, Sue E. Moore3, Ed V.
Farley4, Eddy C. Carmack5, L.W. Cooper2, K E.
Frey.6, J.H, Helle4, F.A. McLaughlin5, S. Lyn
McNutt7, Phyllis Stabeno11 NOAA/Pacific Marine
Environmental Laboratory, Seattle, WA,
james.e.overland_at_noaa.gov2 The University of
Tennessee, Knoxville, TN 3NOAA/NMFS, Alaska
Fisheries Science Center, Seattle, WA4
NOAA/NMFS, Auke Bay Laboratory, Juneau,
AK5Institute of Ocean Sciences,, Sidney,
Canada6 Department of Geography, University of
California, Los Angeles, CA7University of Alaska
Fairbanks, Fairbanks, AK
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POSTERS Igor Belkin
Bering Sea Frontal Pattern Douglas Dasher
Aleutian Islands, Coastal Environmental
Monitoring
Assessment Program
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Recent loss of sea ice in southern Bering Sea
Spring 2000-2005
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Vertically Averaged Temperature (C) at M2 2
deg C increase in winter after 2000
Above freezing point
Stabeno
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Southern Bering Sea Ecosystem Changes
Warm temperatures favor pollock over Arctic
species
1999
2003
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Northern Bering Sea Ice Concentration ( Aprils
2000-2004) and St. Lawrence Temperature Changes
Coming out in Science
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Change in Benthic Biology SW of St. Lawrence
Island -Grebmeier
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10 M new Salmon in the N. Bering Sea in 2004-
following increase northward movement of
pollock - Helle
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Walrus herd in the Chukchi Sea June 2002
M. Webber-USFWS
Clam food in walrus stomachs
photos courtesy G. Sheffield
Schematic of food web in the northern Bering and
Chukchi Seas Grebmeier and Dunton 2000
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Persistent Arctic Changes
Sea Ice Decreasing
From NSIDC
Tundra shown in Pink
Tundra Decreasing
Overland and Wang 2005a Wang and Overland 2004
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Arctic Oscillation (AO) Index
EOF 1 Sea Level Pressure
Thompson and Wallace, 1998 Geo. Res. Let.
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Climate Patterns
Temperature Anomalies
1977-1988 (PNA)
1989-1995 (AO) 1996-2004 (Arctic
Warm) Pacific North American
Arctic Oscillation
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New Climate Pattern
Air Temperature
Wind/Pressure fields

Overland and Wang, GRL, 2005b
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Its too warm!
Future Continued ice reductions due to Arctic
feedback processes (winds, clouds, ocean
currents) Or Shift to different climate
pattern within next 5 years with eventual return
to warm pattern
Thanks for support from NOAA Arctic Research
Program North Pacific Research Board
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Spotted seals are found much further in from the
ice edge 300 km vs. 25 km