Columbia International Affairs Online: Working Papers

CIAO DATE: 03/2009

Rainfall Shocks, Markets, and Food Crises: Evidence from the Sahel

Jenny C. Aker

December 2008

Center for Global Development


How do markets respond to extreme rainfall in West Africa? This paper examines the effect of weather on grain market performance in Niger, a country increasingly affected by drought and severe food crises over the past two decades. Using a dataset that combines information on rainfall, agricultural production, prices and transaction costs, I exploit rainfall variation to estimate the impact of drought on grain market performance between 1997 and 2006. Time series tests suggest that grain markets in Niger respond to supply shocks and that markets are more integrated during drought years. Exploiting the exogeneity of extreme rainfall in a difference-in-differences framework supports these findings: drought reduces grain price dispersion across markets. This impact is stronger as a higher percentage of markets are affected by drought, as was the case in 2004/2005, the year of a severe food crisis. The results suggest that early warning systems in West Africa should focus on the spatial impact of drought at the sub-regional level, as well as monitor prices in key forecasting markets during the harvest period.