Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 108-111). Also available via the Internet.

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 177-180). Also available via the Internet

No description available.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 121-125). Also available via the Internet.

Thesis (M.Sc.)(Meteorology)--University of Pretoria, 2004. / Title from opening screen (viewed March 11th, 2005). Summaries in Afrikaans and English. Includes bibliographical references.

Thesis (M.S.)--Florida State University, 2005. / Advisor: Sharon E. Nicholson, Florida State University, College of Arts and Sciences, Dept. of Meteorology. Title and description from dissertation home page (viewed Jan. 26, 2006). Document formatted into pages; contains ix, 58 pages. Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin, 1966. / This research was partially supported by the United States Weather Bureau under contract WBG-27. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 36).

An improved dynamic electrothermal model for the Earth Radiation Budget Experiment (ERBE) total, nonscanning channels is formulated. This model is then used to accurately simulate two types of dynamic solar observation: the solar calibration and the so-called pitchover maneuver. Using a second model, the nonscanner active cavity radiometer (ACR) thermal noise is studied. This study reveals that radiative emission and scattering by the surrounding parts of the nonscanner cavity are acceptably small. The dynamic electrothermal model is also used to compute the ACR instrument transfer function. Accurate in-flight measurement of this transfer function is shown to depend on the energy distribution over the frequency spectrum of the radiation input function. A new array-type field-of-view (FOV) limiter, whose geometry controls the input function, is proposed for in-flight calibration of an ACR and other types of radiometers. Finally, the point spread function (PSF) of the ERBE and the Clouds and Earth's Radiant Energy System (CERES) scanning radiometers is computed. This PSF is useful in characterizing the channel optics. It also has potential use for recovering the distribution of the radiative flux coming from the Earth by its deconvolution with satellite measurements. / Ph. D.

Recent satellite measurements have found the range of solar radiation flux at the mean Earth-Sun distance to be from 1365 to 1372 W/m², or 1368 W/m² to within ±0.5 percent. This regularity is considered sufficient to permit the use of solar radiation as a source of energy for inflight calibration of radiometers designed to detect electromagnetic radiation in the solar spectrum. But direct viewing of the Sun would provide a flux considerably greater than the operating range of radiometers designed to observe typical Earth scenes. Therefore an attenuator is required. The Earth Radiation Budget Experiment (ERBE) radiometers, operational since 1984, relied on a mirror attenuator mosaic (MAM) to attenuate the solar energy. The ERBE MAM is an array of 105 tightly packed concave spherical mirrors with a black mask covering the surface between the hemispherical cavities and partially covering the cavities themselves. In principle, the reflection of solar energy by the MAM was anticipated to be independent of the solar incidence direction. Unfortunately, flight data revealed a variation with a solar incidence angle of as much as 20 percent for flux arriving at the detector during solar calibration. An improvement of the ERBE MAM design, suppression of the black mask, and reduction of the surface area of the spherical mirrors, has been achieved for the Clouds and the Earth's Radiant Energy System (CERES) radiometers, which will be operational sometime in the late-1990's. The topic of this thesis is the creation of a thermal-radiative model, based on the Monte-Carlo ray-trace method, to characterize the performance of the CERES MAM. The radiative analysis suggests that the current CERES MAM design is still somewhat less than optimal. The desired specifications are that the fraction of solar energy reflected by the MAM to the radiometer aperture be independent of the solar vector, and that the distribution of this reflected energy be uniform across the entire surface area of the radiometer aperture. The work reported here establishes that these specifications can be met by a simple reorientation of the MAM diffuser plate. / Master of Science

The Earth Radiation Budget Experiment (ERBE) uses Angular Dependence Models (ADMs) to convert satellite observed radiances to radiative fluxes at the top of the atmosphere. Owing to errors in scene identification and to the relationship between the spatial scales of cloud systems and the spatial resolution of the ERBE scanner, the anisotropy of the radiation fields determined from ERBE observations was suspected of exhibiting a field of view size dependence. In order to remove effects due to the spatial scale of cloud fields, ERBE scanner observations from the Earth Radiation Budget Satellite (ERBS) were averaged to construct observations having a constant size field of view for all scan angles. Comparing the anisotropy for constant size fields of view with that obtained using unaltered full-resolution scanner observations, it was found that there were significant and systematic differences of the order of 5-10% for all scene types. The frequencies of occurrence for clear, partly cloudy, mostly cloudy and overcast cloud categories identified by the ERBE scene identification algorithm were calculated for the constant size field of view observations. It was found that the ERBE scene identification method failed to correctly identify scene types. A bispectral threshold method was developed for scene identification. In the determination of the thresholds, the ERBE scene identification method was assumed to be correct for nadir observations. The thresholds were then determined so that the population of scene types remained constant from nadir to limb for the constant size field of view observations. ADMs were developed using the threshold scene identification method. Results showed that the spatial-scale dependence of the ADMs was significantly reduced. The threshold ADMs satisfied the principle of reciprocity more closely than did the ERBE ADMs for all cloud categories. Using the threshold scene identification, the view zenith angle dependence of the global average albedo and the longwave flux were significantly reduced compared with those obtained using the ERBE scene identification. The estimated global average albedo increases from 0.282 for the ERBE algorithm to 0.299 for the threshold algorithm. There was no significant change for the value of the estimated longwave flux. / Graduation date: 1994