The 2012 sea ice season may not just break but smash the record for lowest sea ice extent since satellite recording began in 1979 (more likely the last fifty years). From the interactive monitors that I have seen online, we may already have less ice coverage than the previous low in 2007.
http://arctic.atmos.uiuc.edu/cryosphere/arctic.sea.ice.interactive.html
http://arctic.atmos.uiuc.edu/cryosphere/
So, let’s try and figure out what all this means for polar bears, specifically Churchill’s polar bears. The most obvious answer is that if the climate continues to warm and sea ice continues to decline there will be no more habitat and, of course, no more polar bears. Scientific predictions of an ice-free September in the arctic range from years 2100 to 2030 to 2012…!! So, since we will still have 2.9 million square kilometres of ice in the arctic that last one might have been premature.
As for Churchill’s polar bears, this actually means not much at all in the short-term – they are already ashore with females and cubs coming ashore in early July (7th-ish) and the rest of the population heading ashore around July 24th-ish…
In the long-term, less ice coverage means that more heat is absorded into the Arctic Ocean – white reflects heat, dark colours absorb it – and then more heat is emitted from the water leading to greater ice melt. Again, long-term looking pretty Catch-22 right now.
What does this mean for polar bears in general? From what I can see, surprisingly little right now. Yes, the climate is warming – man-made, natural or both (my preference) – but this record low seems to have been actually spurred by a huge and rare arctic storm (on August 8th, I think) which dispersed the ice floes to a greater extent and sped up melting. Not to say that ice extent was not already very low – but since the 2007 record low, we have to expect that sea ice will not rebound anytime soon – in other words, 3 million square kilometres of sea ice in September is the new norm, we just have to hope to maintain this level.
So here is where it gets complicated… The ‘good’ news is that this storm was centred west of the Canadian Arctic and kind of north of Russia. This is a place where few polar bears choose to live so that’s good. Bears actually like shore ice and the open water areas associated with it. The vast expanse of sea north of Russia does not seem to be too attractive.
Secondly, most of the ‘sea ice’ in the Canadian arctic (where the majority of polar bears live) has already melted. There are many polar bears on shore right now – it actually turned out to be a bit of a fallacy that Churchill’s polar bears were the only bears that became ‘stranded’ on land. It has actually been several years of near-ice free Septembers for many polar bear populations.
Finally, unless I am mistaken, the satellite images and global computer models seem to have a tough time measuring shore ice – the polar bears’ most critical habitat. From what I hear (and what I hope) is that there is a bit more sea ice than what the computers are spitting out.
And again, remember that not all polar bear populations are in the same situation… (like comparing New Yorkers to Californians, I suppose). Basically, here is what I have gathered…
- Hudson Bay’s bears (Churchill, South Hudson Bay and Foxe Basin) should have an average year – not a particularly early break-up but there definitely was less ice than historically on the bay
- Baffin Island’s bears should have a pretty decent year, still some nice areas of shore ice, late spring in several places, good condition. Davis Strait bears always seem to have a good year now with the bounty of seals including their new addition to their diet – Harp Seals – in the area
- High Arctic bears (Lancaster Sound, Kane Basin, Norwegian Bay, Viscount Melville) – again should be a good year – still a lot of ice but some nice open water spots – bears actually prefer annual ice for hunting compared to the heavy, thick multi-year ice
- Central Arctic (McClintock, Gulf of Boothia) – should be pretty average, hard to say
- Beaufort Sea bears – doesn’t look like a great year for them, seems to have been some pretty hot weather in that area early in the summer and very, very low ice coverage from what I can see… not good at all.
The ‘upside’ if you can call it that, is that usually when weather conditions kind of offset each other between Hudson Bay/east Arctic and the west Arctic – usually a bad bear season in one place translates to a good season in the other, plus the vast majority of polar bears live in Hudson Bay/Baffin Island areas… whether this happens this year, well stay tuned…
This is just what I have gathered from google and gossip in the north… take it for what it is.
Something very very interesting in all this though… if Shell Oil would not have cancelled their arctic drilling plans for this season, it seems to me that they would have just gotten rolling in time for a rare and powerful summer arctic storm to hit. Something to think about… lost in all the climate change talk is the fact that an arctic oil spill will devastate any polar bear population within range.
