The Use of RDT Nowcasting Tool for Detecting Convective Areas Associated with High Ice Water Content during HAIC/HIWC Field Campaign 2015-01-2124

Glaciated icing conditions potentially leading to in-service event are often encountered in the vicinity of deep convective clouds. Nowcasting of these conditions with space-borne observations would be of a great help for improving flight safety and air-traffic management but still remains challenging. In the framework of the HAIC (High Altitude Ice Crystals) project, methods to detect and track regions of high ice water content from space-based geostationary and low orbit mission are investigated.

A first HAIC/HIWC field campaign has been carried out in Australia in January-March 2014 to sample meteorological conditions potentially leading to glaciated icing conditions. During the campaign, several nowcasting tools were successfully operated such as the Rapid Development Thunderstorm (RDT) product that detects the convective areas from infrared geostationary imagery. The RDT tracks clouds, identifies those that are convective, and provides a temporal and spatial description of their microphysical, morphological and dynamical properties. Comparison of in-situ measurements collected during the HAIC 2014 flights show that there is a good detection of convective cells, and most of the time, high concentration of ice water content was found inside the contours of convection delimited by RDT. Investigations on how to optimize RDT to improve detection rate on convective cells that contain high ice water content, to constrain precisely convective areas to their minimal size and to characterise missed convective cells are conducted. For this, a study is carried out, that combines ice water content satellite estimates from different algorithms with RDT.