Alaskan Arctic Economic Access : Faster than Expected

James OverlandNOAAPacific Marine Environmental Laboratory Seattle

Alaska

250 Miles ofOpen Water North of Alaska

NOAA Cross-Line Office Response to Shell 2012 Sea Ice Season Request

Shell OilKulluk

Shell Oil

SEA ICE SEPTEMBER 2012~50 % loss of extent from climatology

NSIDC

Sea Ice Reanalysis recently verified by satellite thickness estimates

Schweiger et al. 2011, Maslowski et al. 2012Laxon et al. 2013

75 % Loss in Sea Ice VolumeSince the 1980s

June Snow Cover 2012 relative to 1971-2000

Polar Bears Loss of Habitat Walrus haul-outs move to North Of Alaska Land

Walrus calf Carin Ashjian, 2004

Ringed Ribbon

Atmospheric Storm in Pacific Arctic

September 2010 and August 2012Alaska

2010

“Arctic Amplification”: Why New Normal? Global Warming +Multiple Feedbacks

Global Warming

Reduction of Arctic sea Ice

Arctic amplification

Surface albedo decrease

Atmosphere warming

Heat releases to atmosphere in the fall.

Teleconnection and circulation pattern change

Ocean absorbs more heat

JAS SSTASept Sea Ice Extent

OND Temp Anomaly

ArcticAmplification

From E Carmack

Cascading Climate Impacts to Ocean and Biology

“Better” CMIP5 Climate Models

“Better” CMIP5 Climate Models

Predictions

Human forcing is known or already in the climate system. Summer Arctic wide sea ice loss is very likely to occur within a decade or two, based on multiple information. But summer open water is happening now in Alaska

For 2100: Model Results

Mitigation scenario (Rcp 4.5) late fall +7 °C ; late spring +2 °C

Business as usual (Rcp 8.5) late fall +13 °C ; late spring +5 °C

Hot Arctic-Cold Continents Hot Arctic-Cold ContinentsHot Arctic-Cold Continents Hot Arctic-Cold Continents

Added Ocean Heat Storage and Heat Flux to Atmosphere from New Sea Ice Free Areas

Increased Weather Linkages?Arctic-Mid Latitude Linkages “Warm Arctic-Cold Continents”

February 2010Winter 2009-2010 was most extreme in 145 years of Measurements

Potential Arctic Connections can make it colder and snowier in Mid-latitude winter and Drought in Summer (varies a lot)

Not Just Global Warming Everywhere