Hydrometeorological Disasters

Highest number of death and infrastructure damage caused by natural disasters in Southeast Asia in the last 5 years is predominantly related with hydrometeorological disasters such as floods, droughts, landslides, cyclones and tidal waves.

Frequency of those disasters are predicted to be intensified by climate change and inappropriate environmental management.

Increasing frequency of hydrometeorological disasters is also happening worldwide. Global data indicates that 76% of disasters during 1900 – 2011 are categorized as hydrometeorological disasters and the trend is increasing.

The United Nations Office for Disaster Risk Reduction (UNISDR) has been addressing hydro-meteorological disasters as a future major challenge for the society.

Why does the problem exist?

Policy makers need reliable and advance early warning system to minimize the number of victims, save lives, property and infrastructure damage from the disasters. The early warning systems are often built upon historical data.

Rainfall is considered as a major cause of flooding and/or landslide, despite stream network, catchment capacity or tidal influence. Potential damage is dependent on total amount, intensity and duration of rainfall.

A typical flood/flash-flood/landslide forecasting system is often based on rainfall monitoring/historical data.

However rainfall forecast for the coming days is more relevant to explain the probability of extreme rainfall will trigger a disaster (flood/flash-flood or landslide) instead of monitoring.