Satellite altimetry-implied sea ice distribution in the Weddell Sea, Antarctica

We investigated the distribution of sea ice using Topex/Poseidon(T/P) and ERS-1 radar altimeter data in the northwest Weddell Sea, Antarctica, between the area 45-75/spl deg/W and 55-66/spl deg/S. Using the Geo/spl I.bar/Bad/spl I.bar/1 flag of the Merged GDR of Topex/Poseidon, we classified the surface into ocean, land, and sea ice based on the return waveforms. A total of 257 cycles of altimeter measurements between Oct. 1992 and Sep. 1999 (for nearly 2570 days) were analyzed to visualize the distribution of sea ice. We then calculated the surface area of ice coverage using SUTM20 map projection to quantify the periodic variations. Each year, the maximum and minimum coverages of sea ice were found in early October and March in the study area, respectively. We also studied the sea ice distribution using ERS-1 altimeter data between 45-75/spl deg/W and 55-81.5/spl deg/S. Using the valid/invalid flag of the ocean product, we studied the sea ice distribution between March and August of 1995, which showed very good coherence with the T/P measurements.