From the BSES trip log. Looks like The Guardian and BBC entirely fabricated their stories about missing sea ice as the cause.

Sea Ice and Polar Bears!
July 27th, 2011
After arriving in Longyearbyen to see our first midnight sun we were all so relived to see our tents set up and waiting. I think we must of all dreamt of Polar bears because the next day was eagerly waiting for the ice flows to break up so we could move on to base camp. There was a P.bear sighting across the fjord about a mile away. Unfortunately a Westerly wind and freak climatic events have led to an unprecedented amount of ice in the fjord meaning we are marooned here for the time being. Despite this everyone was in good spirits because we encountered another P.bear floating on the ice, this time we were lucky enough to borrow an kind Norwegian guides telescope to see it properly. After that experience I can say for sure that everyone dreamt of P.bears that night. The ice flows are still dominating the fjord and our movements. We understand the depression causing the Westerly wind may not move off until Sunday. In light of this we have planned to strike camp and re locate to a more remote part of the island – should we find ourselves un able to get the boats to base camp again. During our time here we have explored Longyearbyen’s surrounding area. Although we are all itching to move to base camp, many including myself are thinking of home and the people awaiting our return. We are all thinking about you and want you to know everyone is enjoying themselves. Five weeks will fly by out here.
I have written too much now but there is still so much more to say, so be anticipating the many stories we will be coming home with.
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h/t to Marc Morano