Atmospheric Liquid Water and Rainfall Rate Determination over Land Surfaces Using the Nimbus VI Scanning Microwave Spectrometer.
Abstract
The purpose of this study is to determine water vapor and liquid water content from the Nimbus 6 SCAMS instrument over land surfaces. The radiative properties of clouds and precipitation in the SCAMS channels are investigated using the discrete-ordinate method for approximating the solution of the radiative transfer as it is applied to nonisothermal, inhomogeneous cloudy atmospheres. An examination of the problem of variations in surface emissivity over land in the microwave spectrum is included. Analysis of the upwelling radiances from the model in the presence of clouds indicates that the concentration of water vapor and liquid water in atmospheres over land surfaces has a consistent and predictable effect on the observed brightness temperatures. The reuslts of the theoretical calculations are parameterized and an empirical method to derive water vapor and liquid water from the observed upwelling radiances is described. Satellite passes from five days over the United States are used to test the empirical parameterizations of the theoretical results. The empirically derived liquid water contents for two days are compared with synoptic discussions and NOAA 4 satellite mosaics, as well as previous infrared research for the same time period (Feddes and Liou, 1978).
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1978
- Accession Number
- ADA058397
Entities
People
- Alan Douglas Duff
Organizations
- Air Force Institute of Technology