Wayne, I believe it was you that said arctic sea ice doesn't really start growing until surface temps reach -14C consistently (at Neven's a year or two ago).Looking at some of the buoys we can often see a temp spike at -14C in both spring and fall. Thinner ice is more likely to show a spike at -14 than thicker ice. Is this a brief surge due to the phase change? Indicating bottom melt has begun?It's also visible on the overall DMI north of 80 graphs for many different years. This year's DMI graph for instance shows a spike at -14C. Should we interpret this as a large area north of 80 was ready to begin bottom melt as soon as the temps reached -14? Probably due to the fact most of it was thinner ice?
Hi Kevin, sorry I was out of internet world for a bit. I would say -10 to -11 C. There is a melt but its complex, doesn't last if the sun is low or with windier conditions? (still working on the wind effects). The subject requires intense reviewing, buoys mass balance (sonar) are really good, but need perfecting, they are also so few of them , barely grasping the real action of the melting ice, particular to this year, when the ice melts more in one spot and less in the other. I also tend to think that sonar melts would show up a weird behavior of sudden collapse of the ice bottom, as opposed to a slow gradual thinning of sea ice layer. This has a lot to do with the underwater current and tidal activities.