5 Aug 2014, Matt Shupe [73N, 168E].
The sea ice has been very active in this area of the East Siberian Sea. You can tell by all of the pressure ridges around, some protruding many meters above the surface. These ridges occur when large ice floes run into each other, causing little mountain ranges of ice. Satellite images over the last couple weeks suggested that this area had a high ice concentration, and at this time of year that often means there is increased pressure in the ice; convergence of the ice pack due to a variety of forcing factors. That appears to have been the case here in the not so distance past. Large ridges are everywhere, but they are a bit old, the remnants of past weeks. More recently this area has been subject to the blob of heat that has been sitting overhead for nearly a week. While the surface is near the melting point (~0C), the temperature at 400m overhead is a whopping +18C. The atmosphere and clouds that sit up in that warm, moist air aloft emit tons of radiation down towards the surface that ends up melting a lot of ice. Melt ponds in this area have generally melted through, leaving black holes down to the deep ocean below. The scene is all a bit surreal. Kind of like a battlefield from the past: Clear signs of massive destruction from all the ridging, but then time (heat) has eaten away at the scene, softening the edges.
Pressure ridge
