Water Stress Index and Risk
the Water Stress Index is defined as the relative difference between actual and potential evapotranspiration. Therefore higher values of the average index imply more stress on crop growth due to water deficit.
Water Stress Risk can be evaluated with the probability of exceeding a certain value of the Water Stress Index, indicating that the crop is not meeting water requirement. The threshold can be set by the user (default is 0.5). So the Risk is computed as the probability of exceeding a chosen value according to many simulations driven by different predicted weather realizations.
The KSPM was produced by the International Research Institute for Climate and Society (IRI) for review by the United States Agency for International Development and partners on the BAWP and do not necessarily reflect the views of USAID.
Contact help@iri.columbia.edu with any technical questions or problems with this Map Room.