Polar bear habit more extensive in most areas of the Arctic compared to previous years

Mid-November is half-way through the Arctic fall season (October-December) and polar bear habitat is expanding slowly. Here’s a look at fall conditions compared to previous years, so you can see where bears may still be ashore and fasting (i.e. Hudson Bay and southern Foxe Basin) and where others have already resumed feeding.

Sea ice conditions at 12 November 2021

Courtesy NSIDC Masie

Sea ice conditions back to 2012

In particular, compare conditions in the Chukchi Sea (between Alaska and Russia), the Barents Sea (north of Norway) and Hudson Bay over the last decade: you’ll notice more ice in the Chukchi and Barents Sea this year and a bit less in the western Canadian Arctic and Hudson Bay than almost every other year.

Chart below is the only one I have for 12 November 2012, which came after the lowest September minimum extent since 1979 and sent climate scientists into a panic. There was actually some ice along the west coast of Hudson Bay which this view does not show and the apparent ice in James Bay and the Gulf of St. Lawrence are ‘artifacts’ generated by this particular NSIDC satellite algorithm (see the Canadian chart that follows):

Conclusion

Caption: Comparative graph showing ice extent at 12 November 2021 compared to 2012, the 1981-2010 average (solid black line) and 2 standard deviations (grey shading, which indicate values within natural variation), courtesy NSIDC Interactive.

Fall is the second-most important feeding period for polar bears. Given that global polar bear numbers have remained stable or somewhat increased since 2012, depending on which numbers you believe, and that body condition and reproductive indicators in most regions suggest thriving populations, I’m not seeing evidence that fall sea ice levels over the last 10 years have contributed to an ’emergency’ situation for polar bear survival.

In other words, despite Arctic sea ice falling to very low levels in mid-to-late September most years this decade, sea ice has expanded remarkably within the following two months as it has always done with no apparent negative repercussions for polar bears.

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