The Unequal Burden of Heat: Spatial Heterogeneity in Productivity Responses in French Agriculture

This article assesses the short- and medium-term effects of extreme heat on agricultural productivity across French departments during 1980-2023. Using high-resolution ERA5-Land temperature data and CORINE Land Cover, we construct a sector-specific Extreme Degree Days (EDD) index, weighted by cropland and pasture shares to capture sector-specific thermal stress. We estimate department-specific impulse responses via local projections and find significant and persistent productivity losses following heat shocks above 29 °C, with effects intensifying over a four-year horizon and attenuating only modestly thereafter. A Wald test confirms substantial regional heterogeneity in sensitivity to extreme temperatures. The negative impacts are particularly pronounced in lower-productivity, livestock-oriented departments clustered between 44.5° and 46° north latitude. These findings underscore the macroeconomic relevance of a spatially disaggregated measure of exposure to extreme temperatures and highlight the urgency of region-specific adaptation strategies as these episodes intensify.