In response to this morning's links post, commenter Stephen B argued that:
I don't think one needs to be any kind of climate scientist to understand what is about to happen to the remaining ice. In the next 3 years, at some point, the remaining ice is going to be so thin and so relatively fresh, that late one summer in say, August of 2014 to 17, scientists are going to look at their satellite data, and see essentially zero ice. Anybody that's watched a large lake or bay melt understands how they go. First, the edges fray. Some chunks break off, but the main slab grows thinner, wetter, darker, and more "rotten." Then one day in the spring the whole thing, say like 75% of the surface, just breaks up to slush in a matter of hours and it's gone.I grabbed the ice volume data from Piomas, computed the minimum volume each year, and plotted the result above. Note that 2012 is not final as there's still several weeks of the normal melt season left.
The purple line is a linear trend - explaining 82% of the variance. It clearly has systematic problems - the ice collapse is accelerating, not just proceeding linearly.
A quadratic (red) is a visibly much better fit and explains 92% of the variance. The quadratic hits zero in 2017.
It doesn't seem crazy to think that the Arctic will be ice free in September sometime this decade.
Strange that explorers competed for years to travel by sled to a place that will no longer exist. Maybe I'm naive, but it seems this will change the debate about climate change - the complete absence of a polar ice cap seems much easier for an ordinary person to understand, versus complex arguments about data-analysis on global temperature statistics, requiring that you trust scientists and their computer models. Arguing that climate change isn't happening will become akin to arguing that the earth is flat.