The recent article at WUWT
NSIDC Reports That Antarctica is Cooling and Sea Ice is Increasing trumpets the observation that Antarctic sea ice is increasing. This is expected from climate modeling. Nice to see someone else is picking up on this interesting confirmation of our scientific expectation.
The prediction is old. In 1992 Manabe and coworkers, in running a changing CO2 experiment, noticed that the Antarctic sea ice cover increased with increasing CO2. They traced this to increased fresh water on the Antarctic ocean, which derived from increased precipitation -- snow. They also observed in their model that the Arctic ocean sea ice experienced a marked decline in thickness, and major loss of extent in the summer, but not so large a decrease in the winter. At the time they wrote, it was still being debated whether there were trends in the Arctic or Antarctic sea ice covers.
The trend in Antarctic ice cover managed to be statistically significant by about 1997, as documented in
D. Cavalieri, P. Gloersen, C. L. Parkinson, J. C. Comiso, H. J. Zwally,
"Observed Hemispheric Asymmetry in Global Sea ice Changes", Science,
278, pp 1104-1106, 1997. And it was indeed the expected (by Manabe and coworkers) increase. As well as the expected decrease in the Arctic.
That left the question of the mechanism. Did Manabe and coworkers identify the correct reason for the sea ice expansion? Increased snowfall on Antarctic sea ice was documented in 2006 --
Markus, T., and Cavalieri, D. J., "Interannual and regional variability
of Southern Ocean snow on sea ice", Annals of Glaciology, 44, pp 53-57, 2006. (sorry, paywall here).
Since I'm a modeller, I focus on the modelling aspect. Skeptical science (recently added to blogroll) has a different take about Antarctic sea ice, looking more at atmospheric and ocean temperatures
Watts Up With That's ignorance regarding Antarctic sea ice, with more to come.
