Antarctic, ice, ice shelves, water, melt onset, QuikSCAT, refreeze, SeaWinds, Special Sensor Microwave/Imager (SSM/I)


Ku-band dual-polarization radar backscatter measurements from the SeaWinds-on-QuikSCAT scatterometer are used to determine periods of surface freeze and melt in the Antarctic ice shelves. The normalized horizontal-polarization radar backscatter (sigmao) and backscatter polarization ratio are used in maximum-likelihood estimation of the ice state. This method is used to infer the daily ice-surface conditions for 25 study locations located on the Ronne, Ross, Larsen, Amery, Shackleton, and other ice shelves. The temporal and spatial variations of the radar response are observed for various neighborhood sizes surrounding each given location during the study period. Criteria for determining the dates of melt onset and freeze-up for each Austral summer are presented. Validation of the ice-state and melt-onset date estimates is performed by analyzing the corresponding brightness temperature (Tb) measurements from Special Sensor Microwave/Imager (SSM/I) radiometers. QuikSCAT sigmao measurements from 1999 to 2003 are analyzed and found to be effective in determining periods of melt in Antarctic ice sheets at high temporal and spatial resolutions. These estimates can be used in studies of the climatic effects of the seasonal and interannual melting of the Antarctic ice sheets.

Original Publication Citation

Kunz, L. B., and D. G. Long. "Melt Detection in Antarctic Ice Shelves using Scatterometers and Microwave Radiometers." Geoscience and Remote Sensing, IEEE Transactions on 44.9 (26): 2461-9

Document Type

Peer-Reviewed Article

Publication Date


Permanent URL






Ira A. Fulton College of Engineering and Technology


Electrical and Computer Engineering