Hudson Bay freeze-up 2014 – average again this year, not late

Freeze-up of Hudson Bay sea ice is well underway now, virtually the same time as it was the last three years, and in 2008. Bears in the north will be able to move out, while near Churchill and in Southern Hudson Bay, some bears will be able to successfully hunt for seals on the newly-formed ice close to shore.

Over the next week or so, all the bears onshore will gradually move out onto the ice as freeze-up progresses. By the time there is ~10% ice coverage on the bay, most bears will have moved onto the ice (except pregnant females that have made dens onshore).

The Arctic outbreak underway in over North America may hasten this process along (see 7-day and 14-day weather forecasts for Churchill). Ice maps below courtesy Canadian Ice Service.

Sea ice extent Canada 2014 Nov 13 CIS

It seems pretty clear now that time of freeze-up on Hudson Bay is not correlated with the extent of sea ice at the September minimum. Have a look at the maps and graphs below.  UPDATE: more recent maps added below (ice concentration 15 November; ice development 14 November).
15 November added below:
Sea ice extent Canada 2014 Nov 15 CIS

Hudson Bay freeze-up ice development_Nov 12 2014

14 November added below:

Hudson Bay freeze-up ice development_Nov 14 2014

Freeze-up also occurred at this time back in 2008, as reported by Kelsey Eliasson on his PolarBearAlley blog. And last year, he described in detail the sequence of freeze-up and movement of bears around Churchill – it’s worth a read if you’re interested.

See these previous freeze-up posts for the last few years:
Hudson Bay freeze-up average this year – not late [most detailed] November 13, 2013; Hudson Bay freeze-up has not been a day later each year since 1981 November 22, 2013; The sea ice is back and polar bears are heading out November 14 2012; A more optimistic view of Churchill polar bears and Hudson Bay freeze-up November 11, 2014.

But most importantly, note in the graph below (from NSIDC) that freeze-up dates for Hudson Bay over the last few years are not correlated with overall Arctic sea ice extent in September: freeze-up was ~mid-November in 2012 (the lowest minimum extent recorded since 1979), as it was in 2013, 2014 and even 2008. And as I noted in an earlier post, breakup was later in 1983 (by about two weeks) than it has been recently, despite the overall high ice extent in September that year.

The great hue-and-cry over September sea ice extent tells us nothing about freeze-up timing on Hudson Bay and the migration of Churchill polar bears that gets so much attention every fall.

Sea ice extent 2014 -2010_2008_1983 NSIDC interactive graph at Nov 13 2014

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