INDIRECT MEASUREMENTS OF ATMOSPHERIC TEMPERATURE PROFILES FROM SATELLITES: VI. HIGH-ALTITUDE BALLOON TESTING

Abstract

The balloon model of the Satellite Infrared Spectrometer has been flown with balloons at altitudes of about 30 km. from Palestine, Tex. and Sioux Falls, S. Dak. The instrument was calibrated in flight by reference to an internal blackbody at a measured temperature; radiances were deduced for each of the six intervals in the 15-µ band and the interval at 11.1µ in the window. During the Palestine flight the balloon passed over clear areas and over cumulonimbus clouds whose tops were at about 250 mb. From data in each area, the vertical temperature profile was deduced and compared with radiosonde data; in the cloudy areas the profile was limited to the region above the clouds. From data in the 11.1-µ channel, surface temperatures were deduced; the temperatures, corrected for atmospheric water vapor, were compared with special surface temperature measurements and with screen temperatures from Weather Bureau stations. Because of strong radio frequency interference, the 15-µ channels of the Sioux Falls flight were of reduced quality and it was possible to retrieve only a few data for the temperature profile; however, the 11.1-µ data were satisfactory for good surface temperature determination.