Early Warning Systems at Different Time Scales

Abstract:

Early Warning Systems (EWS) reduce the negative aspects of natural hazard impacts on vulnerable communities. Despite its frequent use as a term there is no real ‘one size fits all’ approach to EWS and the system may comprise of different elements depending on the time scale of the hazard, the quality of the information available to make decisions, as well as the population needs and habits. In most developing countries, the primary hydro-meteorological hazards are droughts and floods. These two hazards demand very different approaches: droughts occur over long time scales and are generally a consequence of a gradual process of reduced rainfall across a rainy season; Floods may be caused on seasonal timescales as well due to an overactive rainy season, but the most extreme consequences and loss of life are often suffered at short timescales and relate to flash flooding caused by severe thunderstorms, monsoon extremes and tropical cyclones.

This presentation will address the issues around implementing successful EWS and how these can be targeted to different time scales of hazards. Case studies illustrating the benefits of early information use and action will be shown along with open questions for debate on how the science community might better engage and help develop solutions to hazard warning.