Climate change and agriculture in South Asia: adaptation options in smallholder production systems

Many studies have examined the role of mean climate change in agriculture, but an understanding of the influence of inter-annual climate variations on crop yields in different regions remains elusive. We use detailed crop statistics time series for ~13,500 political units to examine how recent climate variability led to variations in maize, rice, wheat and soybean crop yields worldwide. While some areas show no significant influence of climate variability, in substantial areas of the global breadbaskets, >60% of the yield variability can be explained by climate variability. Globally, climate variability accounts for roughly a third (~32–39%) of the observed yield variability. Our study uniquely illustrates spatial patterns in the relationship between climate variability and crop yield variability, highlighting where variations in temperature, precipitation or their interaction explain yield variability. We discuss key drivers for the observed variations to target further research and policy interventions geared towards buffering future crop production from climate variability.

The coming decades are likely to see increasing pressures on the global food system, both on the demand side from increasing population and per capita consumption, and on the supply side from greater competition for inputs and from climate change. This paper argues that the magnitude of the challenge is such that action is needed throughout the food system, on moderating demand, reducing waste, improving governance and producing more food. It discusses in detail the last component, arguing that more food should be produced using sustainable intensification (SI) strategies, and explores the rationale behind, and meaning of, this term. It also investigates how SI may interact with other food policy agendas, in particular, land use and biodiversity, animal welfare and human nutrition.