Attribution of historical changes in labour outcomes to climate change

The extent to which changes in labour force outcomes can be attributed to historic climate change is currently unknown. Here, we combine robust estimates of the impact of climatic stressors on labour supply, labour productivity, and a combined metric of the two - effective labour, with novel historic climate forcing data to quantify the effect of historic climate change on labour. We do this at the global and regional level, taking explicit account of heterogeneity of working conditions. Glob- ally, effective labour in outdoor working conditions was 1.8 percentage points lower in 1901-2019 than it would have been without climate change. The attributable declines have increased over time, rising to 3.6 percentage points between 2001 and 2019. The highest declines have been in the relatively lower-income regions of Western Africa, South-Eastern Asia, and Middle Africa, where climate change has increased workforce inequalities. We also estimate the economic effects through impacts on GDP and find up to a 12% GDP loss for some regions. Our findings can help improve the design of better labour protections, improve worker health, enhance productivity and economic growth, and inform better climate adaptation and resilience.