Analysis of drought indicators based on a national coupled hydrological model. Identification of drought events, propagation of drought indices, aggregation level and illustration of how data from HIP realtime model can support vulnerability assessment for damages to houses

There is no operational definition on drought (Hisdal and Tallaksen, 2000), scientists have only agreed on very general or conceptual definitions of a drought, e.g. Beran & Rodier (1985): “The chief characteristic of a drought is a decrease of water availability in a particular period over a particular area. Another example (WMO and GWP, 2016). “A drought impact is an observable loss or change at a specific time because of drought”. Since droughts span a broad set of conceptual meanings or circumstances ranging from meteorological, agricultural, built environment, groundwater to socioeconomic droughts, no single operational definition applies to all circumstances. Therefore policy makers, resource planners, and others have trouble recognizing and planning for drought, and this is why drought planners rely on mathematic indices (anomalies) to decide when to start implementing water conservation or drought response measures.