Microwave Monitoring of Aviation Icing Clouds.

Abstract : A field demonstration of passive microwave radiometers was used to assess the usefulness of remotely-sensed cloud properties for the purpose of providing aviation icing hazard advisories. The microwave system measured air temperature profiles, from surface to 10,000 feet, cloud liquid water content, and cloud base altitude. Radiosondes provided temperature air truth, a ceilometer provided cloud base air truth, and pilot reports provided icing condition air truth. Temperature profiles from the microwave remote sensing system agreed with radiosonde temperature profiles to an RMS accuracy that was predicted prior to the field experiment from simulation calculations. Integrated water vapor content measurements agreed with radiosonde values, indicating that microwave integrated liquid water content values were also valid. Microwave-generated cloud bases were in fair agreement with ceilometer values. Icing advisories from the microwave system correlated with the rate of pilot reports of icing conditions. The false alarm rate was nil, and the 'hit rate' was good.