Data from NASA's A-train constellation of satellites are analyzed to examine global relationships between aerosol, clouds and precipitation. The data are applied to two specific studies. The first addresses the response of cloud water path to atmospheric aerosol burden and the second quantifies relationships between tropical precipitation and radiation.

The first focused study presents an examination of aerosol indirect effects on warm oceanic clouds. The study centers on the water path response of cloud to aerosol burden. It is demonstrated that high aerosol environments are associated with reduced liquid water path in nonprecipitating clouds. Furthermore the reduction in liquid water path is greater in thermodynamically unstable environments than in stable environments. In sharp contrast with nonprecipitating clouds, the cloud liquid water path of precipitating clouds increases dramatically with aerosol. Following from these observations, the magnitude of the aerosol indirect albedo sensitivity (IAS) is calculated over the global oceans. The IAS, defined as the change in warm cloud albedo for a fractional change in aerosol, is found to be −0.42 ± 0.38 Wm⁻² over the global oceans. Twenty five percent of the effect is due to precipitating clouds despite the fact that only eight percent of clouds are identified as precipitating.

The second focused study presents an analysis of anomalous precipitation, cloud, thermodynamic, and radiation variables on the tropics-wide spatial scale. It is found that the tropical mean precipitation anomaly is positively correlated with the top of the atmosphere reflected shortwave anomaly and negatively correlated with the emitted longwave anomaly. The relationships are found to result from a coherent oscillation of precipitation and the area of high-level cloudiness. The correlations manifest themselves radiatively as a modest cooling at the top of the atmosphere and a redistribution of energy from the surface to the atmosphere. The anomalous atmospheric column radiative heating is found to be about 10% of the magnitude of the anomalous latent heating.