Dr. Susan Crockford
Svalbard is still ice-free this fall, which it has been rather consistently for at least ten years but the amount of sea ice greater than ‘normal’ in the Eastern Canadian Arctic at this date is something to behold. Yet contrary to predictions, polar bears in Svalbard are thriving.
All the dark blue on the chart below shows ‘much greater’ sea ice than usual in Hudson Bay and east of Baffin Island (compared to the long-term average for 1991-2020), suggesting conditions more like the 1980s for polar bears:
Indeed, excess ice goes all the way up Davis Strait into Baffin Bay for this third week of November:
I couldn’t find any archived ‘departure from normal’ charts I’d archived that had this much dark blue in Davis Strait at this date. The closest I could find was 2017, which was also a really early freeze-up in Hudson Bay:
Oddly, 2018 was similar for Hudson Bay but not Davis Strait:
Here is what the regional ice chart for 24 November 2022 looks like:
For comparison, the same week in 2016–the last time polar bears left the shore of Western Hudson Bay as late as the first weeks of December:
For the same week last year:
Svalbard (Western Barents Sea)
Sea ice coverage around Svalbard in the Barents Sea was the 10th lowest on record, which means there have been many years with less ice than this.
Compared to other years, note that this year is about the same as 2012 (when summer ice hit a record low) but not the lowest this has been:
Polar bears that used to make maternity dens around Svalbard either den on the sea ice or go to Franz Josef Land to the east, where there was ample ice a month ago: habitat all within what is officially the ‘Barents Sea’ subpopulation boundary.
Two weeks ago (10 November 2022), sea ice had reached the north coast of Novaya Zemlya:
Results of the annual survey done this year, discussed here, showed polar bears are still doing well despite about six times as much sea ice loss as other Arctic regions. The bears know what to do, despite hand-wringing by one vocal specialist who thinks that ice conditions as he knew them more than two decades ago is how conditions should remain forever or catastrophe will ensue.
In fact, a 2019 study showed female bears around Svalbard have been thriving in recent years despite the lack of “essential” ice.
“Unexpectedly, body condition of female polar bears from the Barents Sea has increased after 2005, although sea ice has retreated by ∼50% since the late 1990s in the area, and the length of the ice-free season has increased by over 20 weeks between 1979 and 2013. These changes are also accompanied by winter sea ice retreat that is especially pronounced in the Barents Sea compared to other Arctic areas” [Lippold et al. 2019:988]
Lippold, A., Bourgeon, S., Aars, J., Andersen, M., Polder, A., Lyche, J.L., Bytingsvik, J., Jenssen, B.M., Derocher, A.E., Welker, J.M. and Routti, H. 2019. Temporal trends of persistent organic pollutants in Barents Sea polar bears (Ursus maritimus) in relation to changes in feeding habits and body condition. Environmental Science and Technology 53(2):984-995.
via Watts Up With That?
November 25, 2022 at 09:07AM