Climate and Dynamics
Diurnal rainfall pattern observed by Tropical Rainfall Measuring Mission Precipitation Radar (TRMM-PR) around the Indochina peninsula
Article first published online: 15 APR 2010
Copyright 2010 by the American Geophysical Union.
Journal of Geophysical Research: Atmospheres (1984–2012)
Volume 115, Issue D7, 16 April 2010
How to Cite
2010), Diurnal rainfall pattern observed by Tropical Rainfall Measuring Mission Precipitation Radar (TRMM-PR) around the Indochina peninsula, J. Geophys. Res., 115, D07109, doi:10.1029/2009JD012155., , , and (
- Issue published online: 15 APR 2010
- Article first published online: 15 APR 2010
- Manuscript Accepted: 16 NOV 2009
- Manuscript Revised: 5 NOV 2009
- Manuscript Received: 30 MAR 2009
- diurnal cycle;
 This study addressed the diurnal cycle of rainfall during the summer monsoon season (May to September) around the Indochina peninsula, with a focus on the diurnal cycle's relationship to terrain. The investigation used 10 year (1998–2007) Tropical Rainfall Measuring Mission Precipitation Radar (TRMM-PR) observations. Results revealed that the diurnal variations in rainfall over the Indochina region had three distinct peaks. An early afternoon maximum of rainfall occurred along the mountain ranges and on coastal land. Evening rainfall was observed near the foot of mountain ranges, in a valley, and in a basin-shaped plain; this rainfall weakened before the middle of the night. Heavy rainfall in the early morning was found around the coasts over the eastern Gulf of Thailand and the Bay of Bengal, as well as over the eastern Khorat Plateau. We found that nearly half of the total rainfall occurred in the early morning over these regions, which indicated that early morning rainfall significantly contributes to the climatological rainfall pattern. Note that the regions with early morning heavy rain did not correspond to windward faces of mountains but to the windward plain or to an offshore area apart from the mountain ranges in the windward direction. Additional examination of rainfall frequency and rainfall intensity showed that this early morning heavy rainfall was composed of frequent or long-lasting rainfall events with a strong intensity.