A Three-Hourly Data Set of the State of Tropical Convection Based on Cloud Regimes

Tropical convection is a key driver in the climate system and is often identified using infrared satellite information or precipitation. Satellite-derived cloud regimes offer an alternative with potentially more informative distinctions between different types of convection. However, current ISCCP cloud regime data sets require visible satellite information and are therefore only available during daytime. We develop a convective regime data set for all three-hour intervals of the day using ISCCP infrared-only retrievals. We show that regimes derived in this way capture the essential properties of the original regimes, in particular, when identifying the state of tropical convection. We give examples for potential applications by illustrating the well-known Madden-Julian Oscillation and the diurnal cycle of convection in the framework of the newly derived regimes. The high temporal resolution, long record and global coverage of the regimes makes them a suitable tool for large-scale studies of tropical convection.

Tan J. and Jakob C. (2013) A Three-Hourly Data Set of the State of Tropical Convection Based on Cloud Regimes. Geophysical Research Letters, 40, 1415-1419.