Determining precipitation probability of tropical midlevel clouds using satellite observations

Midlevel clouds are underrepresented in global climate models and numerical weather prediction models. One of the main reasons for this is because their characteristics are not as well studied as their high and low counterparts, particularly in the tropics. Recent investigations show that midlevel clouds, specifically cumulus congestus, have an important contribution to tropical precipitation and can precondition the atmosphere for the development of deep convection. With the aid of the space-borne lidar and radar instruments within NASA's “A-Train” constellation, we can improve our knowledge of mid-level clouds. These instruments retrieve several properties of clouds, which will allow for a better understanding of the formation and precipitation mechanisms of midlevel clouds.

Satellite observations from the AIRS, MODIS, CALIPSO, and CloudSat instruments in the A-Train are synthesized for a study on the differences between precipitating and non-precipitating midlevel cloud characteristics in the Tropical Western Pacific. We will compare physical cloud properties, such as cloud depth, height, temperature, and horizontal extent, between precipitating and non-precipitating clouds. Additionally, we will examine environmental properties like temperature and moisture profiles, to determine how these characteristics correlate with precipitation. This analysis will be used to determine how the likelihood of precipitation in midlevel clouds may be inferred from a combination of passive-retrieved cloud and environmental properties. The combination of these satellite observations will provide insight into the characteristics and structure of precipitating midlevel tropical clouds.