Spatiotemporal Pattern of Extreme Rainfall Events in Indochina Peninsula

Abstract

Rainfall is the most influential weather parameter affecting human lives, besides being a natural resource that is needed by humans it can also be a source of disasters if it gets to its extreme. This extreme rainfall is a big problem for the society, thus the analysis of extreme rainfall is needed to design mitigation strategies. This study describes the extreme rainfall phenomena based on statistics that focused on the existence of trends in Consecutive Dry Days (CDD) and Consecutive Wet Days (CWD) and characteristic of its distribution. The trends were obtained from high-quality grid precipitation data compiled by Asian Precipitation-HighlyResolved Observational Data Integration towards Evaluation of Water Resources (APHRODITE) over Indochina Peninsula (4°-25°N and 90°-112°E). This analysis were selected from the list of climate change indices recommended by World Meteorological Organization-Commission for Climatology (WMO-CCI) and the research program on climate variability and predictability (CLIVAR). Linear trends were calculated by least squares fitting and significant or non-significant trends were identified using Mann-Kendall test. The result revealed contrasting trends of each index in the eastern and western Indochina Peninsula. In the eastern Indochina Peninsula mostly indicated positive trends in CWD and negative trends in CDD with some grids showing significant trends, contrary to western Indochina Peninsula. The percentages of positive and negative significant trends of CDD are 10.88% and 2.41% respectively, while for CWD index are 6.85% and 14.51% respectively from a total of 248 grids.