Antactic sea ice

Last September the arctic sea ice reached (recent) record low extent. This led to a discussion about antarctic sea ice being at or near (recent) record high extent. It was also insinuated that the antarctic situation was being downplayed, hidden, whatever.

I return to this now because of a new paper in Nature Geoscience:

http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo1767.html

"Important role for ocean warming and increased ice-shelf melt in Antarctic sea-ice expansion"
doi:10.1038/ngeo1767

The Nature Publishing Group would be most pleased if you sent them $32 to read it, but as you know, other options exist.

Those in a hurry may make do with my brief summary. Increased melting of antarctic grounded ice puts a 'lens' of low-salt, low-density water on the antarctic-ocean surface. Being a cold place, this water freezes.

I mention it for my usual reasons.

1. Simple, goal-oriented interpretations of observations (e.g., "global warming has been disproved") do not lead to deeper understanding of the climate system.

2. Negative feedbacks exist in the climate system. In this case, a large area of sea ice has high albedo (reflectivity). Melt too much off antarctica, and the cooling effect kicks in. So, it falls in my category of 'good news', especially in the authors' interpretation that the mechanism could slow sea-level rise.

3. Current climate models do not effectively capture this mechanism (along with some others I have mentioned previously). If we are to use such models as a basis for carbon policy, they had better be comprehensive.