A Radiative Heating Model Derived from the GATE MSR Experiment

Abstract

A seven-channel Multi-spectral Scanning Radiometer (MSR) was flown aboard the NASA Convair-990 aircraft during the GARP Atlantic Tropical Experiment (GATE) from June?September, 1974. The radiometer measures the total shortwave (0.2?5 ?m) and longwave (5?50 ?m) components of radiation and the radiation in specific absorption band and window regions that modulate the total radiation flux. Measurements of the angular distribution of radiation, including the upward and downward components, were obtained. The principal scientific objective of the MSR experiment was to obtain the atmospheric absorption data required for precise computations of radiative heating profiles from atmospheric state parameters. The method used to construct the infrared radiation heating computational model based on in situ GATE MSR observations is described. Radiative heating profiles computed with this model for both cloudy and cloudless atmospheres were compared with direct observations by flux radiometers and with profiles computed with the Rodgers and Walshaw model. The results indicate that the empirically based computational model should provide tropospheric radiative heating profiles sufficiently accurate for diagnostic and prognostic applications of GATE data.