摘要
Various flood disasters in the last decade have confirmed that the risk from flooding has been increasing significantly worldwide. The driving factors for the risk are the unabated increase in global population, the concentration of people in high-risk areas such as coasts and flood plains, the rise in vulnerability of assets, infrastructure and social systems, and the consequences of climate change. Risk reduction is based on comprehensive risk management from identification of the hazard and assessing the risk to building defenses. To achieve this, general awareness at all levels in a society is key. It is not sufficient merely to be aware of the situation-findings must be acted upon with no significant delay. Flood-related computations have progressed considerably in recent years, but model results can only be as good as their input data. Modeling floods and flood losses is very complex, as model parameters are subject to change during an event and conditions sometimes greatly depend on small-scale factors.