B3 1 Morison

Recent Changes in the Arctic,The Study of Environmental Arctic Change: 

Recent Changes in the Arctic, The Study of Environmental Arctic Change James Morison Chair of SEARCH SSC Polar Science Center University of Washington Seattle, Washington USA morison@apl.washington.edu

SEARCH: 

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. Future course unknown, but Fingerprint of global warming Requires long-term program of observations, analysis, modeling, and assessment.

Ocean ChangesSalinity Difference, Pargo ‘93 - Climatology: 

Ocean Changes Salinity 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) 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

Ocean ChangesTemperature Difference, Pargo ‘93 - Climatology: 

Ocean Changes Temperature Difference, Pargo ‘93 - Climatology Appearance of warm cores over ridges Increase in Temperature maximum of over 1.5° Atlantic Water Temperature maximum is shallower 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

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Ocean Changes Pacific-derived surface waters off Ellesmere Is. Fresher at Coast Saltier at Pole Fresher Water NPEO ’00 CTD Survey Beaufort Sea surface water is fresher and moving east.

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Ice and Atmospheric Pressure Changes ICE THICKNESS DECREASED 42% in last 30 years Beaufort High decreased and shifted east in 1990s Transpolar Drift of ice shifted axis counterclockwise producing a more cyclonic motion in 1990s Ice extent decreased 3% per decade

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Terrestrial Changes Thawing of Frozen Ground Permafrost temperatures rising in Russian Arctic. Permafrost temperatures in the intermittent permafrost region of Alaska have been rising. Permafrost temperatures falling in eastern Canada.

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Ecosystem Changes Barents Sea fisheries shifting north Whale migrations shifting with reduced ice extent Brackish water sea ice ecosystems in Beaufort Sea Massive Bering Sea coccolithophore blooms Large increase in Bering Sea jellyfish population More terrestrial plant growth

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Unaami The complex of changes that have dominated the Arctic in the last 2 decades From the Yup’ik word meaning tomorrow, synonymous with change for Arctic residents - Transportation - Food gathering - Quality of life Unaami characterized by: - 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

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Atmospheric Changes The Arctic Oscillation (AO) Warming in northern Europe and Russia is correlated with AO. Changing Northern Hemisphere circulation - Dominant pattern (EOF1) is centered over Arctic. - Magnitude of EOF1 (AO index) increases since ‘70s. (Thompson and Wallace, 1998) (Thompson and Wallace, 1998)

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Unaami Links to Polar Vortex Rising AO lowers atmospheric pressure over the Arctic. (Thompson and Wallace, 1998) Low pressure spins up Polar Vortex, brings warm air to Greenland Sea and Russian Arctic Warm air over Greenland Sea allows warmer Atlantic Water in Arctic 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 Arctic Ocean Circulation - Increases export of fresh water Increases stratification in Greenland and Labrador seas Inhibits MOC

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Could Unaami be due to greenhouse warming? (Shindell et al., 1999) (Fyfe et al.,1999) AO observations EOF 1 in GHW simulation with stratosphere GHW Simulation GHW Simulation GHW Simulation Control Simulation Observed - earlier and larger than simulated Yes, or Unaami may indicate what’s to come. Simulations suggest spin up of the Polar Vortex is part of greenhouse warming response. AO Index

SEARCH Strategy: 

SEARCH Strategy

SEARCH Organization: 

SEARCH Organization Science Plan: http://psc.apl.washington.edu/search/ index.html