Les bénéfices de la prévision saisonniére pour l'agriculture en Afrique de l'Ouest

The future of sub-Saharan Africa depends on the capability of the agricultural sector to guarantee food security for the vast majority of the population while the rapid growth of the population and climate change are threatening food production. The use of climate forecasts is a promising and costless option for the agricultural sector that might help African farmers to take crucial strategic decisions that would reduce their vulnerability and increase farm profitability. However, even if seasonal forecasts are made routinely in West Africa, adoption by farmers is too low to provide any reliable ex post evaluation that could assess observed outcomes following the adoption of actual forecast schemes. Ex ante evaluation (i.e., assessing the benefits of forecasts in advance of their adoption by society) remains the best way to evaluate such forecasts in West Africa. The present paper uses two recent studies to illustrate this ex-ante approach for evaluating the advantages of using climate forecast in West Africa. Both studies found that farmers could gain benefit from using climate forecasts to orient tactical decision-making in Niger and Senegal. However, such benefits vary across the two locations in West Africa, pointing out the difficulty of generalizing this kind of study. Benefits are also sensitive to the type of year (i.e., dry or wet) and to the quality of the forecasts. Benefits remain moderate since an important limitation of the current seasonal forecasts system is that it focuses on the forecasts of categories of seasonal rainfall amounts, which are less crucial for farmers than predicting the onset and/or the end of the rainy season and the distribution of rainfall within the season.