Crop switching as a strategy for adapting to climate change

This paper examines the impact of climate change on primary crops grown in Africa. An innovative approach is presented that bridges the gap between agro-economic and traditional Ricardian models, labelled by the authors as a &lsquo;Structural Ricardian model&rsquo;. It first captures the type of crop a farmer will select and then examines the conditional net revenue of that crop. Examining the choices that farmers in Africa make across a wide spectrum of climate conditions, the model is estimated using a sample of over 5000 farmers across 11 countries in Africa. <br /><br />The study finds that: crop choice is highly sensitive to both temperature and precipitation farmers adapt their crop choices to suit the local conditions they face. For example, farmers in cooler regions of Africa choose maize-beans and sorghum, whereas those in hot regions choose cowpea and millet.&nbsp;Farmers in&nbsp;dry regions choose millet and sorghum, whereas those in wet regions choose maize-beans, cowpea-sorghum and maize-groundnut farmers often choose crop combinations to survive the harsh conditions in Africa, such as maize-beans, cowpea-sorghum and millet-groundnut. These combinations provide the farmer with more flexibility across climates than growing a single crop on its own analyses of the agricultural impacts of climate change must take into account crop selection. Studies that treat crop choice as exogenous will seriously overestimate the damages from global warming On a cautionary note, the authors admit that this paper only examines choices across currently available crops. Agronomic research could develop new varieties that are more suitable for higher temperatures. These new varieties could substantially improve farmers&rsquo; welfare, especially in hot locations such as Africa. It is asserted that such research could substantially expand the choices available to low latitude farmers and help them adapt not only to current conditions but to future climates as well. <br />The authors also stress that the paper does not address every factor that might be important to crop choice and outcomes in the distant future, including sudden changes in weather, technical change, carbon fertilization, irrigation and changes in cropland. The quantitative results must consequently be taken as suggestive, not conclusive. <br />