Tag Archives: observations

Science behind the video Polar Bear Scare Unmasked – updated paper now available

Announcing the publication today of Version 3 2 of my paper that tests the hypothesis that polar bear population declines result from rapid declines in summer sea ice, updated with recently available data. Version 2 provides the scientific support for the information presented in the GWPF video published yesterday, “Polar Bear Scare Unmasked: The Sage of a Toppled Global Warming Icon” (copied below).

crockford-2017-version-2-title-page-graphic

[The graphic above was created by me from the title page and two figures from the paper]

Updated 1 March 2017: I added an important reference to the paper below that got overlooked in previous versions (the work of Armstrong et al. 2008, see this post), making Version 3 the latest and most up-to-date.

Crockford, S.J. 2017 V3. Testing the hypothesis that routine sea ice coverage of 3-5 mkm2 results in a greater than 30% decline in population size of polar bears (Ursus maritimus). PeerJ Preprints 2 March 2017. Doi: 10.7287/peerj.preprints.2737v3 Open access. https://doi.org/10.7287/peerj.preprints.2737v3

Version 3, published 2 March 2017, adds an important reference; Version 2, published 28 February, incorporates additional reviewer comments and suggestions received on Version 1, as well as the updates noted above.

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New paper updates lack of trend in W Hudson Bay breakup/freeze-up dates to 2015

A newly-published paper shows that there has been no trend in the time Western Hudson Bay polar bears spent onshore between 2001-2015 due to sea ice conditions at breakup or freeze-up (previously available to 2010 only), despite the marked decline of global sea ice since 2007.

castro-de-la-guardia-et-al-derocher-2017-fig-3-no-caption

Figure 3 from Castro de la Guardia (2017) showing freeze-up and breakup dates and ice-free days 1979-2015 for Western Hudson Bay. Figure with caption is copied below, with explanation of symbols.

Previously, a 2007 paper by Eric Regehr and colleagues for WHB bears up to 2004, which was used to support the US bid to list polar bears as ‘threatened’ with extinction, concluded that between 1984 and 2003, bears were spending 3 weeks long onshore than they did in the 1980s.

The big news from Castro de la Guardia (2017) is that polar bears spent longer onshore from 1979-2015 by … 3 weeks. That is, no change from the situation in 2004. Wow!

Note the population size of the entire WHB subpopulation has also not declined since 2004 and is currently estimated at about 1030, based on a 2011 aerial survey (Stapleton et al. 2014).

Thanks to Andrew Derocher for the heads-up tweet.

From the abstract (my bold):

We found that the ice-free period in this region lengthened by 3 ± 0.8 wk over the period 1979−2015. Polar bears migrated onshore 2 wk earlier and offshore 1 wk later in the period 2005−2015 than in 1980−1989.

Here is the region in question, illustrated by Fig. 1 from the paper:

castro-de-la-guardia-et-al-derocher-2017-fig-1a-locationThe significant information contained in this paper is breakup and freeze-up dates and length of the ice-free period data for 2010-2015, which has been unavailable until now. More excerpts and comments below, including Figure 3 with its caption. Continue reading

New paper asks: Has recent sea ice loss caused polar bear populations to crash?

A paper published today finds that predictions of polar bear population crashes due to summer sea ice loss are based on a scientifically unfounded assumption.

crockford-2017-title-page-graphic

[The graphic above was created by me from the title page and two figures from the paper]

Specifically, this paper of mine addresses the basic premise upon which predicted population declines linked to modeled habitat loss made by polar bear specialists back in 2006 and 2008 (by the International Union for the Conservation of Nature, IUCN, and the US Fish and Wildlife Service, USFWS), and concludes that when assessed as a testable hypothesis against data collected since then, it must be rejected.

The forum for this paper is PeerJ Preprints,  which I found while looking for recent research papers about ringed seals. I discovered that Canadian ringed seal biologist Steven Ferguson recently used this service, which is free, open access, accepts review commentary, and will show up on Google and Google Scholar searches.

Ferguson et al. 2016. Demographic, ecological and physiological responses of ringed seals to an abrupt decline in sea ice availability. DOI:10.7287/peerj.preprints.2309v1 Pdf here. https://peerj.com/preprints/2309/

I decided that if this publication forum was good enough for Ferguson and his Arctic research community, it was good enough for me.

Crockford, S.J. 2017. Testing the hypothesis that routine sea ice coverage of 3-5 mkm2 results in a greater than 30% decline in population size of polar bears (Ursus maritimus). PeerJ Preprints 19 January 2017. Doi: 10.7287/peerj.preprints.2737v1 Open access. https://peerj.com/preprints/2737/  (pdf here).

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As polar bear populations fail to decline with sea ice, message of doom intensifies

If 10 years of summer sea ice levels expected to kill 2/3 of the world’s polar bears by 2050 hasn’t had an impact, why would anyone expect a bit less summer ice will do the job?

sea-ice-prediction-vs-reality-2012_polarbearscience

The more the polar bears fail to die in droves, the shriller the message from activist polar bear researchers – via willing media megaphones – that the great death of the bears will soon be upon us, just you wait and see!

Some big media guns were out this past week spreading the prophesy of doom fed to them by the polar bear researchers most committed to the “threatened with extinction” narrative: The New York Times, The Atlantic, The Guardian. The desperation is becoming palpable as the public catches on to their epic failure.

In 2007, the sea ice dropped to a level the experts said wouldn’t be reached until mid-century, and since then, it has remained at that low level (about 3-5mkm2, give or take some measuring error). And in 2007, US Geological Survey (USGS) biologists said with absolute confidence that when sea ice levels reached that point, 2/3 of the world’s polar bears would be gone.

No bears at all would remain, they said, in Western Hudson Bay (the Churchill bears), Southern Hudson Bay, Foxe Basin, Davis Strait, Baffin Bay, Southern Beaufort, Chukchi Sea, Barents Sea, Kara Sea, and the Laptev Sea:  ten out of 19 subpopulations would be extirpated if sea ice levels in most years dropped to the summer lows in the 3-5 mkm2 range.

On the basis of that prediction, polar bears were declared ‘threatened’ with extinction by the US Fish & Wildlife Service (USFWS) under the Endangered Species Act (ESA).

But nothing of the kind happened. There are still lots of polar bears – and not even struggling-to-survive bears but lots of fat healthy bears everywhere across the Arctic, in what were considered by USGS biologists to be the most vulnerable regions of all: Western Hudson Bay (i.e., Churchill), Chukchi Sea and Southern Beaufort (Alaska) and the Barents Sea (Norway).

This is the truth the world needs to hear: the experts were wrong. Polar bears have not been driven to the brink of extinction by climate change, they are thriving. This is the message of each of my two new books (one of which is appropriate for kids of all ages, see the sidebar).

In turns out that polar bears are much more resilient to changing levels of sea ice than data collectors assume and the proof is in the current healthy populations everywhere. Continue reading

No correlation between freeze-up dates for WHB sea ice & Churchill temperatures

This is a follow-up to my last post and this time, I’ll address the implied correlation between freeze-up dates for Hudson Bay and Churchill temperatures in November that is being made by folks who should know better .

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Monday, 14 November 2016 a.m, over at Polar Bears International [my bold]:

“As a new week starts in Churchill, the weather is the warmest we’ve ever seen at this time of year. The tundra is muddy, with remnant patches of snow, and the bay is ice-free.” PBI Blog (no author designated)

Well, that may be true for the last few years – the high on 14 November 2016 (-1.20C) was the highest since 2012.

Andrew Derocher made a similar statement on the 4th (my bold):

There’s no sea ice anywhere in Hudson Bay yet—not even in the northern part of the Bay where ice should be forming. It’s above freezing today and if the forecast holds, it will be a record high for this date. It was 10 degrees colder last year at this time.”

Derocher is being unscientifically vague here and also misleadingly cites highs and lows as if they were the same. In fact, according to weather records kept by Environment Canada, for 4 November 2016 at Churchill, the daily high was +1.50C (compared to –1.50C in 2015). The daily low in 2015 was -15.30C, a 10 degree difference. The next-highest temp. for that date since 2012 was +0.70C in 2014 – hardly an earth-shattering difference.

However, if you are trying to draw conclusions about climate, you should go back at least 60 years (two climate periods of 30 years each). Temperature records for Churchill go back to 1943, which can be used to assess the claim for the 14th of November made by PBI.

According to weather records kept by Environment Canada, for 14 November at Churchill, the year with the highest temperature was 1975 (+2.20C):

churchill-weather-averages-and-extremes-2016-ec-14-nov

That was Monday. But as of yesterday, the weather recorded – and the forecast for the following week (17-23 November) was quite different, as the screencap below shows:

churchill-weather-2016-abnormal-cold-17-23-nov

The final recorded max. for yesterday (Thurs. 17 Nov) was -9.70C vs. a min. of -17.70C. So, a bit warmer during the day than predicted but as cold as expected overnight.

And for today, the current temperature in Churchill, as I write this is, is -190C (-310C with the wind chill) and the year with the highest temperature recorded for 18 November was 1944 (0.00C) – which was also the highest temperature for the 19th, recorded in 1943.

Ice maps and historical background below. See last post for recent multi-year comparison.
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If experts had been right about sea ice, there would be no polar bears in Churchill

The simple fact is that if polar bear experts had been right about the threat to polar bears from the loss of summer sea ice in the Arctic, there would be no polar bears in Churchill this fall. No bears for tourists to photograph, none for biologists to study, and certainly none for the BBC to film for an upcoming three-part TV special called “Arctic Live.

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The low-ice future that biologists said would doom polar bears to extinction by 2050 has already happened in 8 out of the last 10 years. The sea ice future has been realized.

Polar bears have experienced those supposedly deadly low-ice summers for almost a decade but the global population did not drop by 2/3 as predicted and not a single one of the ten subpopulations predicted to be extirpated under those conditions has been wiped out.

How much more wrong can you be than that? Will the BBC mention this conundrum in their show? Will the polar bear experts they consult share this fact with viewers? We’ll all have to watch and see [show times and summaries of each program here, 1-3 November] but here are some background facts that might enhance your viewing experience.

UPDATE: Sea ice condition of Hudson Bay at 1 November 2016 below from the Canadian Ice Service (some slushy ice looks to be forming along the coast north of Churchill – this is how freeze-up starts). See the animation for the last 10 days here:

sea-ice-extent-canada-2016-nov-1_cis

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Ice maps vs. observations in the W. Arctic – polar bear habitat reality check

Last Wednesday (8 June 2016), the US Coast Guard rescued walrus hunters from Shishmaref in the Bering Strait who got stuck in sea ice that is barely visible on sea ice maps. It’s a rare glimpse of what sea ice really looks like up close compared to what you see on the ice maps.

Watch the video here: https://www.dvidshub.net/video/embed/467959

[Unfortunately, the screencaps from the video, like the one below, are less impressive than the film. In the video, you can see the hunters walking on the ice around their trapped boat – the ice does not visibly move]

Shishmaref_ice_CoastGuard 02_8 June 2016

Have a look at the sea ice maps below for the day the incident took place. They show what appears to be hardly any ice in the area.

This is a good lesson for assessing what’s been going on in the Beaufort Sea a bit further east, where winds and currents have opened up a rather large patch of open water surrounded by considerable expanses of sea ice – at issue is the possible impact on polar bear spring feeding for April and May.
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