The NASA Icing Remote Sensing System depends on a Radiometrics Corporation 23-channel radiometer to derive temperature profiles and total integrated liquid water amounts. In addition, the system utilizes a Vaisala Laser ceilometer and a Metek Ka-band radar to define cloud base and top heights. An algorithm based on expected cloud structure, as inferred by these measurements, is used to determine the distribution of liquid water content within the cloud.
Icing-related pilot reports are voluntary accounts and are our only means of in-situ diagnoses of actual atmospheric conditions encountered by aircraft in the absence of expensive icing research flights or specially instrumented fleet aircraft.
The Current Icing Product combines visible and infrared satellite imagery, radar reflectivity, lightning observations, pilot reports and standard ground-based weather observations with numerical weather prediction model output to produce a gridded, hourly, three-dimensional representation of icing probability and severity.
The authors will explore how the S-band freezing drizzle, high differential reflectivity and mixed-phase icing modules of the IHLA behave under varying icing conditions. Quantitative analysis including probability of detection, percent of radar volume warned on and strengths and weaknesses of the algorithm will be discussed. Qualitatively, the input and output fields will be examined to determine how they match the conceptual models of in-flight icing environments.
Supplementary URL: http://www.rap.ucar.edu/projects/icehazard/