Cloud-Precipitation Hybrid Regimes and their Projection onto IMERG Precipitation Data

• DOI: 10.1175/jamc-d-20-0253.1
• Publication Date: 2021-04-02T18:44:37Z
• Authors: Daeho Jin; Lazaros Oreopoulos; Dongmin Lee; Jackson Tan; Nayeong Cho
• Keywords: Centroid; Rainband; Initialization; Precipitation types

Abstract In order to better understand cloud-precipitation relationships, we extend the concept of cloud regimes (CRs) developed from two-dimensional joint histograms optical thickness and top pressure Moderate Resolution Imaging Spectroradiometer (MODIS), include precipitation information. Taking advantage high-resolution Integrated Multi-satellitE Retrievals for GPM (IMERG) dataset, derive “hybrid” by implementing a k -means clustering algorithm with advanced initialization objective measures determine optimal number clusters. By expressing variability rates within 1-degree grid cells as varying relative weight information in algorithm, obtain several editions hybrid (CPRs), examine their characteristics. deep tropics, when is weighted weakly, part centroids resemble counterparts cloud-only regimes, but combined tightens relationship decreasing each regime’s variability. As progressively increases, shape becomes blunter, while sharpens. When are equally, CPRs representing high clouds intermediate heavy exhibit distinct enough features parts allow us project them onto 30-min IMERG domain. Such projection overcomes temporal sparseness MODIS observations associated substantial rainfall, suggesting great application potential convection-focused studies where characterization diurnal cycle essential.