Linking Drought Information to Crop Yield

Friday, 18 December 2015: 14:42
3001 (Moscone West)
Alireza Farahmand1, Shahrbanou Madadgar1, Lei Li1 and Amir Aghakouchak2, (1)University of California Irvine, Irvine, CA, United States, (2)University of California Irvine, The Henry Samueli School of Engineering, Irvine, CA, United States
Droughts have detrimental impacts on agricultural yields all over the world every year. This study analyzes the relationship between three drought indicators including Standardized Precipitation Index (SPI); Standardized Soil Moisture Index (SSI), Multivariate Standardized Drought Index (MSDI) and the yields of five largest rain-fed crops in Australia (wheat, broad beans, canola, lupins and barley). Variation of the five chosen crop yields is overall in agreement with the three drought indicators SPI, SSI, and MSDI during the analysis period of 1980-2012. This study develops a bivariate copula model to investigate the statistical dependence of drought and crop yield. Copula functions are used to establish the existing connections between climate variables and crop yields during the Millennium drought in Australia. The proposed model estimates the likelihood of crop yields given the observed or predicted drought indicators SPI, SSI or MSDI. The results are also useful to estimate crop yields associated with different thresholds of precipitation or soil moisture.