SEASAT Altimeter Atmospheric Range Correction.
Abstract
This report describes the development and validation of the wet term of the atmospheric range correction for the SEASAT altimeter by the Naval Research Laboratory as part of its contribution to the WAFER 82 Sub-Working Group on Acquisition and Exploitation of SEASAT Altimeter Data. The algorithm uses antenna temperatures from the SEASAT Scanning Multichannel Microwave Radiometer (SMMR). It was developed by Macmillian M. Wisler at NRL using an optimal linear estimator, a theoretical-empirical atmospheric-ocean model and a statistical description of the environment. The algorithm tests were performed by the JPL SMMR Evaluation Task Group by comparing the range correction derived from the algorithm with the range correction calculated using radiosonde water vapor measurements from the islands of Bermuda and Kwajalein. The data used for the comparison were taken from eight different orbits during 13-30 September 1978. The wet term range correction varied from 19 to 42 centimeters. Apart from a relatively unimportant systematic bias, which is easily and accurately removed, the algorithm and radiosonde range corrections agreed very well with an RMS deviation of + or - 2.0 centimeters. Improved calibration and antenna pattern corrections of SMMR data and greater radiometric accuracy of future passive microwave systems along with further algorithm development undoubtedly will allow improved accuracy in determination of the range correction. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 25, 1980
- Accession Number
- ADA091504
Entities
People
- James P. Hollinger
Organizations
- United States Naval Research Laboratory