Climate‐sensitivity of sugarcane yield in the southeastern Africa lowlands

Abstract

AbstractWe have analysed the relationships between local and regional climate and sugarcane yield over the southeastern Africa lowlands (31°–23.5°S, 28.5°–32.5°E) for the period 1970–2017. The temporal associations for preceding December–May rainfall and temperature, and indices of the Pacific El Niño Southern Oscillation and Indian Ocean Dipole, demonstrate the climate‐sensitivity of sugarcane yield and its proxy: the Palmer Drought Severity Index (PDSI). The composite differences revealed how the atmospheric circulation over the Mozambique Channel shifts the moisture gradient over southeastern Africa. Predictors of sugarcane yield were identified in point‐to‐field maps of global sea surface temperature, sea level air pressure, and upper winds with respect to the PDSI. It was found that four climate predictors account for half of the PDSI variance at 1 year lead time. We also investigated the long‐term change using coupled model simulations. These exhibit weak drying trends but large year‐to‐year swings in soil moisture. Our research offers a basis for mitigating climate variability for the benefit of the sugar industry in southeastern Africa, through statistical forecasts that inform crop management.