Characteristics of tropical cirrus anvil outflow during TWP-ICE

Tropical cirrus, which can extend over large areas and persist for several days, are an important element in the tropical radiation budget. Cirrus microphysical properties, including particle size, particle shape and ice water content depend on both the formation mechanism and the evolution of the cirrus. Understanding the processes that influence the microphysical properties and lifetime of cirrus clouds is an important step in predicting the role of cirrus in climate feedbacks. During the Tropical Warm Pool International Cloud Experiment (TWP-ICE) field experiment, based in Darwin, Australia during January-February, 2006, a large cyclonic system stalled south of Darwin for several days. This system produced cirrus anvil outflow that was observed by the ground-based remote sensors at the Darwin site and was sampled by in situ instrumentation on the Proteus aircraft on January 29. The cirrus anvil outflow was also observed by the MISR and MODIS instruments during overpasses of the Terra and Aqua satellites. In this study, we examine the microphysical characteristics of the cirrus anvils as a function of age and distance from the convective source using the aircraft in situ observations, the satellite measurements, and the ground-based remote sensing measurements.