What do the 235 estimates from the literature tell us about the impact of weather on agricultural and food trade flows?

Abstract

In light of increasing concerns towards climate change and its implications for global agriculture and international food security, a small but growing literature has assessed the sensitivity of agricultural trade to weather conditions and events. This issue is critical to measuring trade's central role as a market-based adaptation and mitigation mechanism for climate change. By conducting a meta-analysis of this literature, we elucidate several key themes that characterize this nascent body of research. First, we find that temperature in exporting places is the primary weather-based factor affecting agricultural trade and that estimates of this effect are negative in most studies. Second, the marginal effect of precipitation on trade varies greatly across primary studies in terms of sign, magnitude and location (origin or destination of trade). Third, meta-regression results uncover that the main sources of the heterogenous impact of weather on food and agricultural trade found in the primary studies originate from differences in sample size, types of commodities considered, and estimator choices. Future studies shall adopt the most recent estimation techniques, consider the role of irrigation, account for domestic trade, and provide results by commodity whenever possible.