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Staelin, D. H.

Publications and source records attributed to Staelin, D. H..

At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

The Shuttle imaging microwave system experiment

The purpose of the Shuttle microwave system experiment (SIMS) is to utilize the capabilities of the Space Shuttle to perform passive microwave measurements of thermal emission from the earth's atmosphere and surface, which can be interpreted in terms of meaningful atmospheric and geophysical parameters. The paper is a status report of an ongoing definition phase study of SIMS. The wavelengths and observable parameters for the SIMS channels are identified. The SIMS instrument is discussed with particular reference to the antenna system. A system consisting of a parabolic torus reflector offset fed by a number of feeds and radiometers on a rotating wheel is determined to be the best antenna configuration for SIMS. A tentative data flow diagram for SIMS is also provided.

Waters, J. W.↗
NASA NTRS1974

Signatures of various earth surfaces measured by the Nimbus-5 microwave spectrometer

The Nimbus-5 Meteorological Satellite is equipped with a 5-channel microwave spectrometer. The two lowest channels (22.2 and 31.4 GHz) provide information on surface brightness temperature. Distinctive microwave signatures can be observed for snow, land ice, and sea ice in both polar regions. Some information on subsurface temperatures can be gained for desert areas.

Kunzi, K. F.↗
NASA NTRS1974

Review of Nimbus-5 Microwave Spectrometer results

Nimbus-E Microwave Spectrometer (NEMS) data are analyzed, especially those obtained from the 53.65, 54.9, and 58.8 GHz channels, corresponding to sensing at 4, 11, and 18 km respectively. The observations permit highly precise horizontal temperature profiles to be established and are hardly affected by clouds. The sensings of the 54.9 GHz channel unambiguously delineate wave structure on the equator. Horizontal water vapor profiles are derived from the 22.235 and 31.4 GHz channel data.

Staelin, D. H.↗
NASA NTRS1973

Microwave spectrometer on the Nimbus 5 satellite - Meteorological and geophysical data

The Nimbus 5 microwave spectrometer has been used to measure thermal radiation in five frequency bands between 22.235 and 58.8 gigahertz, and has yielded both the temperature profile and, over ocean, the vapor and liquid water content of the terrestrial atmosphere, even in overcast conditions. Information has also been obtained on geophysical parameters that affect the surface emissivity, such as ice type, sea roughness, and snow cover. The experiment demonstrates the considerable potential of passive microwave sensing of meteorological and geophysical parameters.

Staelin, D. H.↗
NASA NTRS1972

Microwave radiometric measurements of atmospheric temperature and water from an aircraft.

A five-channel microwave spectrometer operating near the 1.35-cm wavelength water vapor and the 5-mm wavelength oxygen resonances was flown in the NASA Convair 990 aircraft at altitudes near 12 km and used to infer layer thicknesses and water vapor and liquid water abundances in the troposphere. The calibration of the spectrometer and a multiple regression method of interpretation of the data obtained from the flights are described. Possible errors from clouds and from the terrestrial surface are discussed. Values of atmospheric layer thicknesses, water vapor content, and liquid water content inferred from microwave data obtained over two frontal systems are presented. The inferred values of 1000- to 500-mb and 500- to 250-mb thicknesses agree with directly measured values to within 15 meters at the places where the direct measurements were made. This agreement is equivalent to errors of less than 1 K in mean temperature.

Rosenkranz, P. W.↗
NASA NTRS1972

Remote sensing of atmospheric and surface temperatures with microwaves.

Solids, liquids, and gases emit at microwave wavelengths measurable amounts of black-body thermal radiation. Receiver sensitivities readily approach 0.01 K, and permit accurate measurements of land, sea, and atmospheric temperatures. Sea and land temperature measurements must be corrected for the effects of surface emissivity, but these effects can often be measured or estimated. Observations near the 5 mm wavelength 02 resonances can yield atmospheric temperature profiles with an approximate accuracy of 2 K for altitudes 0-80 km. Such measurements from balloons and aircraft suggest that the planned earth-orbital satellite experiments will yield data valuable for numerical weather prediction. Ground-based radio telescopes and planetary-probes have yielded similar information about the surfaces and atmospheres of other planets.

Staelin, D. H.↗
NASA NTRS1971

Indirect sensing of atmospheric temperature and water vapor using microwaves.

A prototype of the Nimbus E microwave spectrometer was flown in an airplane over various atmospheric and surface conditions. Effects of clouds and the terrestrial surface on the data are discussed. Using a multiple-regression statistical method of inverting the equation of radiative transfer, estimates of temperature and integrated contents of water vapor and liquid water in the atmosphere below the aircraft were made from the microwave data obtained at high altitude. These estimates are compared with direct measurements made by other experiments on board the aircraft, in both clear atmospheres and in the presence of clouds.

Rosenkranz, P. W.↗
NASA NTRS1969

Passive remote sensing at microwave wavelength

The ways in which radio signals are affected by meteorological parameters are described, as are methods for interpreting the signals, the state-of-the-art in instrumentation, the current state of development of the field, and some problems and prospects for the future. It is shown that the temperature profile of the atmosphere, water vapor and ozone distribution, cloud water content, and certain surface properties can be measured with sufficient accuracy to provide useful meteorological information.

Staelin, D. H.↗
NASA NTRS1967

Radio astronomy

Radio astronomy - Haystack-Millstone OH INTERFEROMETER, K-band spectrum measurements of sun, inference of atmospheric attenuation from balloon flights, and microwave emission

RADIO ASTRONOMY↗
NASA NTRS1966

Radio astronomy

Radio astronomy studies in 18-cm line emission sources, fringe visibility of bright radio sources, and spectral features of Venus and Jupiter

INTERFEROMETRY↗