Development and Testing of Drought Indicators

Numerous definitions of droughts which are based on different climatological time series have been in use. In this paper, the development of drought indicators by using different time series is described. These drought indicators were developed for use by the Department of Natural Resources in the State of Indiana, U.S.A. The second part of the study deals with an analysis of the consistency of results obtained by using different time series, in order to select two or three of the commonly available series for drought analysis. Past drought data are used to test the performance of the drought indicators. As a result of this study, three month precipitation, monthly river flow and the Palmer Hydrologic Drought Index series are recommended for operational use.