Convective generated cirrus observed by CRS and EDOP during TC4

Tropical cirrus cloud plays an important role in the Earth's climate system. Cirrus ice crystals scatter incoming sunlight, reducing the solar radiation reaching Earth's surface, resulting in a surface cooling effect. Cirrus clouds also absorb upwelling infrared radiation emitted from the surface and lower atmosphere, reducing the infrared energy escaping the Earth-atmosphere system. The net effect of tropical cirrus on surface temperature depends on several factors including cloud height, cloud thickness, and ice crystal size. A significant portion of the tropical cirrus is directly associated with deep convection. Cloud Radar System (CRS), operating at 94 GHz, same frequency as that of CloudSat, detects both thin and thick cirrus outflow from deep convection but it cannot penetrate deep convection because of its strong attenuation. The ER-2 10?GHz Doppler precipitation radar provides detailed vertical structure of the convective and thick cirrus cloud. During TC4, there were a number of good cases where the ER-2 flew over the DC8 and the WB-57 the last few days. EDOP and CRS data provide information on the convection that produced the cirrus and the cirrus structure. This data combined with other remote and in situ data sets provides a wealth of information for studying the mechanisms of cirrus formation, detrainment in the TTL, and ice retrieval algorithms. This presentation will focus on characterizing cirrus evolution and associated convection from a radar point of view, examining whether there are any obvious signatures of cirrus evolution (particle size, IWC) from ER-2 multiple passes over the same cirrus region. Results from several good cases where the ER-2 flew over convection and then downwind over anvil cirrus in coordination with the DC-8 will be presented. We will apply particle size and IWC algorithms to the cirrus observations to evaluate whether the cirrus is undergoing changes.