HYGROMETER FOR MEASUREMENT OF RELATIVE HUMIDITY IN CLOUDS

AN ACCURATE MEANS IS RQUIRED FOR MEASURING RELATIVE HUMIDITY IN CLOUDS BECAUSE THIS PARAMETER IS ESSENTIAL IN THE EVOLUTION OF CLOUD MICROPHYSICS. THE DEVELOPMENT OF A NEW RH SENSOR CAPABLE OF MEETING THIS NEED IS BASED ON THE OPTICAL MEASUREMENT OF HAZE DROPLETS AS THEY RESPOND IN SIZE TO CHANGES IN AMBIENT RH; AN ACCURACY OF THE RH MEASUREMENT OF +/-0.02 PERCENT IS ANTICIPATED, WITH RH VALUES > 100 PERCENT ALSO BEING MEASURED. A PROTOTYPE SENSOR FOR FIELD USE IS DEVISED, DESIGNED, AND FABRICATED UTILIZING RECENT ADVANCES IN LASER DIODE TECHNOLOGY. RESEARCH INVESTIGATES THE SENSOR'S SURVIVABILITY UNDER ATMOSPHERIC CONDITIONS WITH HIGH WIND SPEED AND LARGE HYDROMETORS. THE SENSOR IS TESTED IN ATMOSPHERIC CLOUDS UNDER SUPERSATURATED CONDITIONS.