Antarctic Sea-Ice Melt Detection
QuikSCAT h-pol slice images are analyzed to determine the onset
and duration of melting in the Antarctic. Daily Sigma-0 measurements for
each image pixel are compared to the respective previous winter's mean
Sigma-0 value. Each measurement falling at least 3dB below this mean is
counted as one day of melt. The total number of melt days are recorded for
the austral summers of 1999/2000 to 2001/2002. The onset of melting for each pixel is
simply the date of the first measurement denoting a melt event, while the
final melt date is the last recorded melt event of the year. Melt days over open ocean
are exaggerated since as the ice edge retreats each pixel previously
representing sea-ice now resides over open ocean and accumulates melt days
as the summer season progresses.
Caution: Estimates over some land areas are affected by noise from the
azimuth modulation of Sigma-O.
Austral
Summer Melt Day Totals
Dates of Melt Onset
Dates of
Final Summer Melt Events
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