Validation of AMSR Snow Depth on Sea Ice Retrievals Using an Airborne Pulse Radar
Project Award Date: 03-01-2002
The Remote Sensing Laboratory at ITTC is performing research to develop an airborne, stepped-pulse radar that will be able to validate the data on snow depth over sea ice, obtained by NASA's Defense Meteorological Satellite Program (DMSP) Microwave Imager (SSM/I) using a satellite-based passive microwave algorithm. Knowledge of snow depth on sea ice is important to understanding many conditions of oceans and the atmosphere. Currently only passive microwave sensors provide the capability to retrieve snow depths from satellites. To verify the satellite data, in-situ, surface-based measurements of the snow depth have been tried. But the value of these sparse, single measurements is limited, as snow depth over sea ice can vary by tens of centimeters or more over several meters due to drifting snow or sea ice age. To gain more confidence in the measurements (on a pixel-by-pixel basis), and to obtain a quantitative estimate of the limitations of the algorithm being used, we need spatially and temporally coincident measurements on the same scale as the satellite data.
A surface-based stepped frequency pulse radar has successfully measured snow depths to an accuracy of about 2 cm. ITTC's research will develop an airborne system that uses Synthetic Aperture Radar (SAR) processing to improve along-track resolution and array processing in the cross-track direction. The collected radar measurements will be used to validate AMSR snow depth on sea ice retrievals during three different field campaigns, including both polar regions and a wide range of sea ice types and snow conditions. After completion of the investigation, accuracy and error sources in the AMSR algorithm should be much better defined and, if necessary, modifications can be made to enhance the retrievals. In addition, the instrument will be available for more detailed, field-based snow studies.
This project involves collaboration with Dr. Thorsten Markus at the University of Maryland.
Faculty Investigator(s): Sivaprasad Gogineni (PI), Glenn Prescott
Student Investigator(s): Sudarsan Krishnan, Brandon Heavey, Ravi Rajaraman, Krishna Kumar Gurumoorthy, Timothy Rink, Kuok-Wai (Wilson) Wong, Bharath Parthasarathy, Jason Henslee, William Donovan, Andrew Yoder
Primary Sponsor(s): NASA