Classification of hydrological drought in lower Mekong delta

Abstract

     Drought is a phenomenon of water shortage compared to the average in a certain period and in a certain space. Hydrological droughts in the lower Mekong Delta are presented according to the Streamflow Drought Index (SDI), and drought severity is classified from normal to severe according to 50%, 75%, 85%, 95%, and above 95% guaranteed occurrence of the events respectively. The SDI and drought classification reflect well hydrological drought on the Mekong mainstream flowing into the lower Mekong Delta, especially since accumulation of the last 3 month flow in previous rainy season presented the influence of the Great Lake in Cambodia are taken into the account. The classification of hydrological drought plays an important meaning in supplementation of other current disaster risk classification criteria in the Lower Mekong Delta,