Figure 3. From Amstrup, Marcot & Douglas 2008, caption from original (as per American Geophysical Union): Area of sea ice extent (>50% ice concentration) on 16 September 2007, compared to 10 Intergovernmental Panel of Climate Change Fourth Assessment Report GCM mid century projections of ice extent for September 2045–2054 (mean ±1 standard deviation, n = 10 years). Ice extent for 16 September 2007 was calculated using near-real-time ice concentration estimates derived with the NASA Team algorithm and distributed by the National Snow and Ice Data Center (http://nsidc.org). Note that five of the models we used in our analyses project more perennial sea ice at mid century than was observed in 2007. This suggests our projections for the future status of polar bears may be conservative. Image credit: American Geophysical Union.