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Gelman, M. E.

Publications and source records attributed to Gelman, M. E..

24 records · Page 2

Direct determination of the thickness of stratospheric layers from single-channel satellite radiance measurements.

The direct use of measured radiances for determining the thickness of stratospheric layers is investigated. Layers based at 100-10 mb, with upper boundaries at 10-0.5 mb, are investigated using a carefully selected family of stratospheric temperature profiles and computed radiances. On the basis of physical reasoning, a high correlation of thickness with radiance is anticipated for deep layers, such as the 100- to 2-mb layer (from about 15 to 43 km), that emit a substantial part of the infrared energy reaching a satellite radiometer in a particular channel. Empirical regression curves relating thickness and radiance are developed and are compared with blackbody curves obtained by substituting the blackbody temperature in the hydrostatic equation. Maximum thickness-radiance correlation is found, for each infrared channel, for the layer having the best agreement of empirical and blackbody curves.

Quiroz, R. S.↗

A regression technique for determining temperature profiles in the upper stratosphere from satellite-measured radiances.

A technique is described whose application makes it possible to almost double the altitude range over which useful temperature profiles may be obtained. For a wide range of atmospheric temperature profiles, the temperature structure between 30 and 55 km may be derived with an expected error of less than 3 C at 30 km to less than 10 C at 55 km, given the temperature structure in the lower 30 km of the profile, and given a consistent and accurate set of radiance observations. For strongly anomalous conditions in the stratosphere, the accuracy of retrievals at tropospheric levels may also be substantially improved.

Gelman, M. E.↗

Stratospheric thickness determined directly from satellite radiance measurements.

Discussion of the use of satellite radiance data for determining the thickness of deep stratospheric layers. Empirical regression equations are shown to provide better estimates of stratospheric thickness than do mean weighted temperatures obtained from the Planck equation. The best regression equations were found for thick layers emitting a substantial portion of the CO2-band infrared radiation measured by satellites. By adding the layer thickness to the observed height field for the lower boundary, it is possible to construct constant-pressure maps at very high altitudes.

Quiroz, R. S.↗