A new set of MODIS Cloud Regimes towards unification with ISCCP Weather States

For almost a decade and a half, Cloud Regimes (CRs) resulting from the systematic classification of joint cloud optical thickness-cloud top pressure histograms derived from passive observations, have been used extensively to investigate precipitation and radiation variability, aerosol-cloud interactions, and tropical convective dynamics and circulation, among others. They have also been used to evaluate the cloudiness of GCMs equipped with satellite simulators capable of generating such joint histograms. The two main CR datasets that have been used for such studies are the ISCCP Weather States and the MODIS CRs. This presentation will describe a part of the effort to create a unified CR/WS funded by NASA's MEASURES program. Specifically, we will introduce a new set of MODIS CRs derived from clustering analysis applied on equal area (~100 km) joint histograms temporally resolved at 3-hour intervals that were generated from MODIS C6.1 Level-2 cloud products for the explicit purpose to match the counterpart ISCCP dataset. This new MODIS CR dataset spans 2003 to present. We evaluate and seek to understand the nature of these new MODIS CRs in terms of their Cloud Vertical Structure as revealed for a 4-year subset that takes advantage of Aqua and CloudSat/CALIPSO coincidences on the A-Train, their precipitation and radiation characteristics, as well as the ensemble mean of spatiotemporally matched ISCCP joint histograms for the overlapping period corresponding to the latest ISCCP H dataset.