Passive remote sensing at microwave wavelengths

Abstract

Passive remote sensing at microwave frequencies has applications which range from meteorology t o oceanography and geology. The meteorological applications are the most fully developed and include measurements of the temperature profile of the atmosphere and of the atmospheric distribution of H,O and 0,. Such measurements can be made from space or from the ground by utilizing the microwave resonances of 0,. H,O. and 0, which occur near 1-cm wavelength. Although infrared observations permit similar meteorological measurements, such optical devices are much more sensitive t o aerosols and clouds. The small but finite nonresonant attenuation of most moderate clouds at microwave frequencies also permits their liquid water content t o be estimated. At wavelengths longer than 2 an the microwave properties of the terrestrial surface dominate observations from space, and measurements as a function of polarization and viewing angle yield information about surface temperature and emissivity. Such measurements of the ocean should also permit the sea state t o be inferred. The review has two major parts. The first part reviews the physics of the interactions, the mathematics of data interpretation, and the instrumentation currently available. The second part is applicationsoriented and emphasizes the types, accuracy, and refevance of possible meteorological measurements.

A Function Theory Method in Boundary Value Problems in the Plane. I: The Smooth Case

“…Microwave radiometry has been reviewed by Staelin (1969), Njoku (1982), Peckham (1987) and is covered in depth in the three volumes by Ulaby ei a l (1981,1982,1986).…”

Analysis of circulation patterns in Grays Harbor, Washington, using remote sensing techniques

“…The instrument measures natural thermal radiation emitted in the microwave range by water and land surfaces and the atmosphere (NASA, 1972). Additional details regarding passive microwave and thermal infrared remote sensing are available in Reeves (1968), Holier (1973, Staelin (1973), Estes (1974), Huebner (1975), Reeves (1975), Fraser and Curran (1976), Janza (1976), and Pogorzelski and Sh apiro ( 197 6 ). A Barnes PRT-5 Precision Radiation Thermometer measured gross apparent radiation transmitted from the earth's surface in the 8-to 14-/*m range (NASA, 1972).…”

Remote Sensing and Modeling of Cyclone Monica near Peak Intensity

“…Temperature and humidity profiles can be retrieved using algorithms similar to those for infrared sounding (see, for example, Staelin [34]), with the advantage of less impact due to clouds. However, microwave sensors have relatively coarse resolutions (50 km for AMSU and 40 km for SSMIS), so the observed brightness temperature must be deconvolved [35] prior to a physically-based retrieval or statistically-based retrieval [22,36].…”