Assessment of global climate change impacts on labour productivity

This study assesses the impact of climate change on outdoor labour productivity at the regional-scale and across the globe. It uses five impact models that describe observed relationships between labour productivity and temperature, with climate model simulations from five Global Climate Models (GCMs) under a high emissions scenario (RCP8.5), i.e. 25 climate-impact model combinations. To the authors' best knowledge this is the first assessment of the heat stress and labour productivity to use multiple impact models with multiple climate models. Impacts are estimated for the end of the century (2070-2099) and near-term (2021-2050), relative to present-day (1981-2010). Impacts are assessed without adaptation. Globally, at the end of the century, the spread in the magnitude of decline in labour productivity across all 25 climate model-impact model combinations is 2-21%. The impacts of climate change are felt heterogeneously across the globe. At the end of the century the greatest impacts are projected for Mexico, Central America and the Caribbean, and South Africa, where the spreads are 3-32%, 2-32% and 3-31% respectively. The UK and Ireland, and northern Europe, experience the lowest impacts: 0-11% and 0-13% respectively. Economic implications assessed under a static-comparative framework indicate that mean annual global GDP losses could reach 0.2% in the 2030s and 0.6% by the end of the century. The respective welfare losses are estimated at 0.3% and 1%, respectively. The mean values hide significant heterogeneity across global regions, socio-economic characteristics and the 25-member ensemble of impact projections. An important conclusion is that the magnitudes of climate uncertainty and impact model uncertainty are comparable for most regions however, for several regions of the globe, impact model uncertainty is larger than climate model uncertainty.