Not predicted: more sea ice than average in southern-most Arctic first week of August

Polar bear habitat update for the first week of August 2019 shows there is still more sea ice than average in Hudson Bay, the southern-most area of continuous habitation for this species. That certainly wasn’t part of the predictions of doom, especially since freeze-up in that region for the last two years has also been earlier-than-average which means a shorter ice-free season than we’ve seen for decades.

Hudson Bay weekly departure from normal 2019 Aug 5

Despite ice coverage for the Arctic ice as a whole being marginally lower than it has been since 1979 for this time of year, sea ice for the first week of August was also above average around Svalbard in the Barents Sea and higher than the last few years in the Central Arctic, which is a critical summer refugium for polar bears that live in the peripheral seas of the Arctic Ocean, including the Chukchi (see photo below, taken in early August 2018).

Chukchi Sea polar bear Arctic_early August 2018_A Khan NSIDC small

Arctic sea ice coverage July

from NSIDC:

sea ice extent 2019 July average vs previous decades NSIDC graph


sea ice extent 2019 July average NSIDC_6 Aug


from Norwegian Ice Service:

Svalbard ice extent 2019 Aug 8_graph_NIS

Svalbard ice extent 2019 Aug 9_NIS

Central Arctic

from NSIDC Masie:

r11_Central_Arctic_ts_4km at 2019 Aug 8

masie_all_r11_Central Arctic v01_2019220_4km

Hudson Bay

Oddly, researcher Andrew Derocher has not posted an update on the locations of his tagged Western Hudson Bay bears since July 27, when at least half (11 or so) were still on the ice. However, it has been a quiet week for problem bears in Churchill, which suggests few starving individuals around – also not a predicted outcome for a low-ice summer for the Arctic.

Churchill problem bears_week 4_2019 July 29-Aug 4 posted Aug 8

All of that thick first year ice adjacent to Southern Hudson Bay shown below (home to the southern-most polar bear subpopulation) means most of the bears in that region will be heading to shore over the next week or so – which would have been about normal back in the 1980s. Again, not what you’d expect for a low-ice Arctic summer. From the Canadian Ice Service:

Hudson Bay weekly stage of development 2019 Aug 5


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