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Center for Nonlinear Studies |
The keystone activity on Antarctic Sea Ice during International Polar Year was the coordination of two dedicated sea ice cruises during the late winter (Sept-Oct 2007). This period coincides with the annual maximum extension of Antarctic sea ice. The two cruises operated on opposite sides of the Antarctic sea ice zone, the NB Palmer at 90W longitude (S.F. Ackley, Chief Scientist) in the Bellingshausen Sea and the Aurora Australis at 110-130E (A.P. Worby, Chief Scientist) off East Antarctica. A common core of ice sampling, ice observations and biogeochemical sampling using similar protocols was conducted on both cruises, allowing a more detailed comparison and contrasting of the sea ice development within the same time period on opposite sides of the continent, not previously achieved. Important adjuncts to these measurements were dedicated satellite data acquisitions from the IceSAT laser altimeter and RadarSAT and EnviSAT ASAR active microwave sensors. Detailed ground truth, enhanced by airborne measurements made by helicopter from the Aurora Australis, allowed better validation of these satellite products and improves the monitoring of Antarctic sea ice in future from space. The third Antarctic sea ice drift station and the first in late winter, Ice Station Belgica, was conducted from the NB Palmer for nearly a month and gave time series measurements of the biogeochemical activity within the sea ice (e.g. CO2, DMS/P, chl a, iron) during this critical period, coinciding with the onset of warming, higher light enhancing biological activity and maximum area coverage of sea ice.
Host: Elizabeth Hunke, T-3