Cambodia is located at the southernmost parts of the Mekong river basin to the delta. The river is the economic and life source of Cambodia with more than three-fourths of 16.9 million people living along the basin. The country is one of the most disaster-prone in South-East Asia with more frequent occurrences of floods and droughts over the last decade. Moreover, the delayed rains during the wet season and flash flooding from the Mekong River have exacerbated disaster events since 2002.
The tropical climate leads to relatively high humidity throughout the year with an average annual temperature ranging from 10 to 38° Celsius (C). Cambodia has a monsoonal climate with equivalent lengths of a wet season (May to November) and a dry season (December to April). Rainfalls also vary across Cambodia with rain-soaked uplands experiencing 3,000 millimeters (mm) while parts of the northeast experience 1,000 – 1,600 mm.
Cambodia is characterized by forested mountains and well-watered plains. The central part features vast basins from the Tonle Sap and the Mekong River. The mountainous region includes the Cardamom Mountains and the Elephant Range located at the eastern plains, and the Dangrek Mountains in the west. Mount Aôral is the highest peak at 1,813 meters (m) and is one of the most uninhabitable parts of the country. The sparse population in this area is due to the overflowing of the Mekong during the rainy season which causes the lakes of the Tonle Sap to increase from 2,590 kilometers (km) to 24,605 km.