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Antarctic Sea Ice Extent
Vyas, N.K., Dash, M.K., Bhandari, S.M., Khare, N., Mitra, A. and Pandey, P.C.  2003.  On the secular trends in sea ice extent over the antarctic region based on OCEANSAT-1 MSMR observations.  International Journal of Remote Sensing 24: 2277-2287.

What was done
The authors analyzed data from the multi-channel scanning microwave radiometer (MSMR) carried aboard India's OCEANSAT-1 satellite for the period June 1999-May 2001 to study sea ice extent over Antarctica.  They then combined their data with data for the period 1978-1987 that were derived from space-based passive microwave radiometers carried aboard earlier Nimbus-5, Nimbus-7 and DMSP satellites to study secular trends in sea ice extent over the entire period 1978-2001.

What was learned
Over the entire period studied, it was determined that the mean rate of change of sea ice extent for the entire Antarctic region was an increase of 0.043 M km2 per year.  The authors additionally concluded that "the increasing trend in the sea ice extent over the Antarctic region may be slowly accelerating in time, particularly over the last decade."

What it means
In the words of the authors, "continually increasing sea ice extent over the Antarctic Southern Polar Ocean, along with the observed decreasing trends in Antarctic ice surface temperature (Comiso, 2000) over the last two decades, is paradoxical in the global warming scenario resulting from increasing greenhouse gases in the atmosphere."  Indeed, it would appear to be a major contradiction of that scenario.

Comiso, J.C.  2000.  Variability and trends in Antarctic surface temperature from in situ and satellite infrared measurements.  Journal of Climate 13: 1674-1696.
Reviewed 30 July 2003