Feasibility Study. The Determination of Thunderstorm Intensity with a Temperature Sensing Shuttle-Borne Lidar (Laser Radar)

摘要

This thesis examines the feasibility of operating a lidar (laser radar) from the space shuttle and having this instrument measure the intensity of thunderstorms. Thunderstorm intensity is monitored by measuring the time rate of change in temperature of the top 0.5 km of a thunderstorm. Severe weather occurring on the ground takes place during, or just after a period of rapid cloud top cooling. Temperature is measured with two wavelengths using a differential absorption lidar (DIAL) technique which determines the resonant absorption of oxygen in the oxygen A band near .7700 micron m. One wavelength is set at .7696 micron m which is a temperature sensitive oxygen absorbing line while the second wavelength is set at .7614 micron where oxygen absorption is negligible. The lidar can measure the oxygen resonant absorption coefficient at the heights of typical thunderstorm tops. A temperature value is recovered by placing the retrieved 02 absorption coefficient into a quickly converging iterative expression. Hypothetical thunderstorms with heights from 10-17 km are probed at shuttle altitudes ranging from 100-250 km. Success of the system is based on useful values of the signal-to-noise ratio. Keywords include: Laser; Lidar; Remote Sensing; Space shuttle; Meteorological instruments; Thunderstorms; and Temperature.