Title and image both stolen from Espen on the Arctic Sea Ice Forum:
Nares Strait is an old favourite on the Arctic Sea Ice blog, because every year it's a surprise when the ice arch/bridge - preventing ice transport from the Lincoln Sea towards Baffin Bay - is going to collapse. This year it happens almost two weeks later than last year, which in its turn was 10 days later than in 2011. What strikes me this year, and maybe I didn't pay enough attention in previous years, is that the break-up was already occuring from within through in situ melting, before the arch gave way.
Ice transport through Nares Strait contributes to ice loss from the Arctic Basin. It it isn't quite as significant as ice transport through Fram Strait (roughly 10% at the most), but the ice that gets transported, is some of the thickest and oldest ice in the Arctic. A NASA-led study by Ron Kwok in 2010 (PDF) showed that transport in 2007 was exceptionally high.