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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 Stabeno1
1 NOAA/Pacific Marine Environmental Laboratory, Seattle, WA, [email protected] 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
POSTERS
Igor Belkin Bering Sea Frontal PatternDouglas Dasher Aleutian Islands, Coastal Environmental Monitoring Assessment Program
Recent loss of sea ice in southern Bering Sea –Spring 2000-2005
Vertically Averaged Temperature (°C) at M2: 2 deg C increase in winter after 2000 Above freezing point
Stabeno
Southern Bering Sea Ecosystem Changes
1999
2003
Warm temperatures favor pollock over Arctic species
E. Bering Sea Crab
0
200
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12001
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82
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Year
To
tal m
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re b
iom
ass
(1
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0 to
ns)
Snow crab C. opilioTanner crab C. bairdiBristol Bay Red King CrabPribilof Is. Red King Crab
Pribilof Is. Blue King CrabSt. Matthew Blue King Crab
Northern Bering Sea Ice Concentration ( Aprils 2000-2004) andSt. Lawrence Temperature Changes
Coming out in Science
Change in Benthic Biology SW of St. Lawrence Island-Grebmeier
10 M new Salmon in the N. Bering Sea in 2004- following increase northward movement of pollock- Helle
[M. Webber-USFWS]
Walrus herd in the Chukchi Sea– June 2002
Schematic of food web in the northern Bering and Chukchi Seas [Grebmeier and Dunton 2000]
Clam food in walrus stomachs
[photos courtesy G. Sheffield]
Persistent Arctic ChangesPersistent Arctic Changes
Overland and Wang 2005aWang and Overland 2004
Sea Ice DecreasingSept 2003
-4 -2 0 2 4 deg C
Warm Surface Temperatures
Tundra shown in
Pink
From NSIDC
Tundra Decreasing
Arctic Oscillation (AO) Index
Thompson and Wallace, 1998 Geo. Res. Let.
EOF 1 Sea Level Pressure
Temperature Anomalies
1977-1988 (PNA+) 1989-1995 (AO+) 1996-2004 (Arctic Warm) Pacific North American Arctic Oscillation
Climate Patterns
New Climate Pattern
Air Temperature Wind/Pressure fields
Overland and Wang, GRL, 2005b
It’s too warm!Future:Continued ice reductionsdue to Arctic feedback processes(winds, clouds, ocean currents)
Or:Shift to different climate patternwithin next 5 years with eventualreturn to warm pattern Thanks for support from
NOAA Arctic Research Program
North Pacific Research Board
Spotted seals are found much further in from the ice edge300 km vs. 25 km
