Influence of ENSO on the Diurnal Cycle of Rainfall over the Maritime Continent and Australia

Abstract

This study examines the influence of ENSO on the diurnal cycle of rainfall during boreal winter for the period 1998-2010 over the Maritime Continent (MC) and Australia using Tropical Rainfall Measuring Mission (TRMM) and reanalysis data. The diurnal cycles are composited for the ENSO cold (La Niñ a) and warm (El Nin o) phases. The k-means clustering technique is then applied to group the TRMM data into six clusters, each with a distinct diurnal cycle. Despite the alternating patterns of widespread large-scale subsidence and ascent associated with the Walker circulation, which dominates the climate over the MC during the opposing phases of ENSO, many of the islands of the MC show localized di..