Trends and variabilities of precipitation and temperature extremes over Southeast Asia during 1981-2017

As one of the most populated agricultural habitats in the world, Southeast Asia has been highly exposed to extremes of weather and climate, posing great importance to figure out the trend and variability characteristics of extremes over there. The annual extreme precipitation and temperature over Southeast Asia during 1981-2017 are analyzed in this study using datasets based on daily observations derived from thousands of meteorological stations. Results show that the wet extremes decrease over the areas surrounding the South China Sea and increase over the south of the Philippines and Indonesia with the most significant trends detected over the east of Indochina and New Guinea. Extreme high temperatures decrease significantly over the middle of New Guinea and increase over Indochina, Sumatra, Java, and Kalimantan. Moreover, empirical orthogonal function (EOF) analyses show that the first principal components for most precipitation extremes are characterized by significant decadal changes relevant to the Atlantic Multidecadal Oscillation and Pacific Decadal Oscillation, and the second principal components exhibit significant interannual variability associated with oceanic systems such as El Nino-Southern Oscillation (ENSO). As for temperature extremes, the leading EOF modes show non-significant trends or decadal variations, but significant interannual variations related to ENSO and the Indian Ocean Dipole are detected.