Publication: Estimating WRSI and YR indices for five selected cultures in NE Brazil


How climate variability and change affects agricultural productivity is also relevant for land use management. In CLIMA, our climate projections are integrated by analyzing the risk of planting a certain crop at a certain date. We calculate the WRSI (water requirement satisfaction index) and YR (yield reduction) indexes that measure the relative losses in crop production due to the occurrence of hydrological stresses, such as drought. The information derived from these calculations is connected to HadGEM2ES-rcp6.0 climate projections, which then serves as a key input to our land use modeling via the BLUM model.

As part of the World Bank’s non-lending technical assistance to the Brazilian Government the CLIMA team developed the CROPCALC software which helps estimate the WRSI and YR indexes for five selected crops (corn, rice, cassava, cotton, and beans) in drought-affected Northeast Brazil. CROPCALC is based on FAO report #56 which provides a guideline for calculating crop water needs. The software incorporates information on soil types and crops to obtain optimized indications for crop planting windows in the NE region, and uses the new series of high-definition (0,25° x 0,25°) meteorological data for the period 1980-2013.

The CROPCALC software, manual, and background report – which includes examples computed by CROPCALC to help the interested researcher or analyst in the interpretation of the results – can be downloaded below.


Obermaier, M., Xavier, A.C., Mendes, H.A., e King, C.W. (2016). Estimações para os índices WRSI e YR para cinco culturas selecionadas na região NE do Brasil. Report for The World Bank, Rio de Janeiro. (In Portuguese only.)

Mendes, H.A. (2016). CROPCALC Manual and Software. Available at:

Photo credit: Hüdson (CC BY-NC 2.0)

Leave a Reply

Your email address will not be published. Required fields are marked *