Towards a Drought Watch System based on Spatial SPI

Regional Drought can be assessed through various meaningful procedures mainly related to the expected consequences. However, a general knowledge of the occurrence of drought, the area which is affected, its severity and its duration are of great importance for a series of decisions, which may be appropriate for a variety of activities. From the existing simple and popular indices used for the estimation of drought, the Standardised Precipitation Index, known as SPI, seems to win universal applicability. A method based on the estimation of SPI over a geographical area and its use for characterising drought, is presented in this paper. Applications of the method are presented using a digital terrain model and a simple computer calculating routine. It is shown that the proposed procedure can be easily applied and can support a Drought Watch System for an area of mesoscale dimensions.