Drought early warning systems: monitoring and forecasting

Drought early warning systems (DEWS) are designed to provide relevant information on the current status (monitoring) and possible duration and evolution over the next few days to months (forecasting) of drought severity and extent. They use a combination of observations (ground measurements or earth observations) and models to derive drought indices, ideally chosen to describe water deficit in rainfall, soil, river and groundwater, and identify the associated level of drought severity. DEWS information should be updated regularly and is generally delivered through interactive web information platforms as maps, time series and reports, covering local/national to continental and global scale. Typical users are from sectors such as agriculture, water management and regulatory authorities, and these users should be involved in the design of DEWS so that the information content and the way it is displayed is relevant and easy to understand. Most DEWS are open and freely available to all.