Satellite thermal microwave sea ice concentration algorithm comparison

• Main Authors: S. Andersen, R. T. Tonboe, L. Kaleschke
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Sea ice concentration; radiometer algorithms; sea ice surface emissivity and; Arctic; Sea ice
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.582.9949; http://ocean.dmi.dk/remote_sensing/rad_sar.pdf

temperarture, sea ice extent and area trends. Seven of the most common radiometer algorithms, used to compute the sea ice concentration, are compared to ScanSAR data estimates of ice concentration. Our focus is on the near 100% ice cover in winter. The sensitivity of the algorithms to the variable sea ice surface emissivity and temperature is the most significant hindrance for correct estimates of ice concentration in this ice regime. The skill of the best radiometer algorithms is significantly better than the worst set, but all correlate poorly to and display higher variability than the SAR data at high ice concentrations. On a climatological time scale the differences between algorithms amounts to 14 % and 22 % of the down-going trend in winter Arctic sea ice extent and area, respectively. The climatological changes in atmospheric and water surface emissivity primarily affects the extent trend while the changes in sea ice surface emissivity affects the sea ice area trend.