Towards a Drought Watch System based on Spatial SPI

Regional Drought can be assessed through various meaningfulprocedures mainly related to the expected consequences. However, a general knowledge of the occurrence of drought, thearea which is affected, its severity and its duration are ofgreat importance for a series of decisions, which may beappropriate for a variety of activities. From the existingsimple and popular indices used for the estimation of drought,the Standardised Precipitation Index, known as SPI, seems to winuniversal applicability. A method based on the estimation of SPIover a geographical area and its use for characterising drought,is presented in this paper. Applications of the method arepresented using a digital terrain model and a simple computercalculating routine. It is shown that the proposed procedurecan be easily applied and can support a Drought Watch System foran area of mesoscale dimensions.