Spatially Consistent Drought Hazard Modeling Approach Applied to West Africa

A critical stage in drought risk assessment is the measurement of hazard, probability occurrence a potentially damaging event. The standard approach to assess hazard based on standardized precipitation index (SPI) and intensity classification established according fixed set SPI values. We show that this method does not allow for region-specific hazards, we propose an alternative extreme value theory. model using mixture model, with normal distribution bulk, generalized Pareto upper lower tails. estimation allows us identify threshold below which can be qualified as extreme. quantile function used measure each category droughts calculate (DHI). By construction, DHI varies specific characteristics left tail distribution. To test relevance our approach, estimate over gridded rainfall data covering West Africa, large climatically heterogeneous region. results fits better than calculation. In particular, performs map highlights clusters high located central part region under study.