Between 2004 and 2005, 665 natural disasters incurred with an estimated death toll of 336.500 lives lost and more than 300 million people being adversely impacted. Besides the Asian tsunami in December 2004 and the earthquake in Pakistan in October 2005, floods were the main cause of the disasters. The total costs of natural disasters in 2005, including the damage caused by Hurricane Katrina, have been estimated at over US$150 billion.

A disaster as severe soil erosion in a river catchment area, caused by deforestation or land degradation, may generate heavy soil sedimentation and result in flooding, storm surge or tsunami. The tsunami of 26 December 2004 is a prime example of how a geophysical disaster can severely impact coastal communities on several continents. Fishery and aquaculture in coastal communities, as well as livelihoods, were adversely impacted, notably in South East Asia. Over 200.000 lives were lost, although this is just a rough estimate. Millions of people in the region were economically debilitated, losing their livelihood, assets and sources of income. Apart from natural disasters there are also military conflicts, demand on water resources