Spatiotemporal change of climatic suitability in sunflower-growing areas of Tanzania

Climate change will alter future crop-climate suitability over different regions of the world. This article assessed the current and future suitability of sunflower cultivation across Tanzania. Meteorological datasets on spatial sunflower suitability were applied under three timescales: baseline period (1970–2000) and future climatic conditions for the average years of 2041–2060 and 2061–2080. They include mean monthly climate datasets from Coupled Model Intercomparison Phase 6 (CMIP6) at ∼1 km² spatial resolution. These datasets were accessed from WorldClim and used to produce suitability maps through Ecocrop model in TerrSet software using the default FAO crop ecological database 2000 under shared socioeconomic pathways; SSP245 and SSP585 emission scenarios for the four general circulation models (GCMs). These models include: HADGEM-GCM31-LL, UKESM1, IPSL-CM6A-LR and MIROC6. The results indicated that temperature will surge to 38 °C, while rainfall will decline and increase in some areas. Model results indicated that the climatically optimal area (COA) for sunflower cultivation occupied 76.6 % in Tanzania by 1970–2000. Future projections showed a decrease in COA by 59 % and 57 % under SSP245 and SSP585 in 2041–2060, with further shrinkage of up to 52 % in 2061–2080 under both scenarios. We recommend a nationwide campaign towards utilization of the existing and future potential suitable climate area for sunflower production. Therefore, farmers and policy makers need to be aware of the future suitability adjustment and hence pay more attention to expand sunflower crop cultivation area. Future crop-climate assessment studies need to focus on other crops in order to create broader coping strategies and adaptation planning.