Measurement of Ocean Surface Winds by Seasat Synthetic Aperture Radar.
Abstract
This report investigates the feasibility of using Seasat Synthetic Aperture Radar (SAR) data for measuring ocean surface winds. An empirical model relating the received power of the L-band SAR to ocean surface wind conditions was evaluated. Results from this investigation indicate that past Seasat SAR wind studies could be biased due to the nature of the measurement techniques employed. In these past studies, densitometer measurements of output imagery were related to wind speed and direction. Because of a shifting of the Doppler spectrum location with latitude due to the earth's rotation and spacecraft attitude change, these measurements are valid only over short azimuthal distances. A theoretical correction was calculated and applied to the Seasat data, resulting in improved correlations with the surface wind speed. Additionally, a simplified measurement technique which did not involve explicit corrections for this Doppler shifting was developed. The results of this study are consistent with those of previous investigations, but yield additional insight into the angular dependence of the SAR backscatter and the accuracy of the technique.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1983
- Accession Number
- ADA138392
Entities
People
- David R. Lyzenga
- J. D. Lyden
- R. A. Shuchman
- W. L. Jones
Organizations
- Environmental Research Institute of Michigan