Limited effect of future land-use changes on human heat stress and
labour capacity
Abstract
To achieve the 1.5°C target of the Paris agreement, rapid, sustained,
and deep emission reductions are required, which often includes negative
emissions through land-based mitigation. However, the effects of future
land-use change on climate are often not considered when quantifying the
climate-induced impacts on human heat stress and labour capacity. By
conducting simulations with three fully-coupled Earth System Models, we
project the effects of land-use change on heat stress and outdoor labour
capacity for two contrasting future land-use scenarios under
high-ambition mitigation. Achieving a sustainable land-use scenario with
increasing global forest cover instead of an inequality scenario with
decreasing forest cover in the Global South causes a global cooling
ranging between 0.09°C and 0.35°C across the Earth System Models.
However, the effects on human heat stress are less strong, especially
over the regions of intense land-use change such as the tropics, where
biogeophysical effects on near-surface relative humidity and wind speed
counteract the cooling effect under warm extremes. The corresponding
influence on outdoor labour capacity is small and inconsistent across
the three Earth System Models. These results clearly highlight the
importance of land-use change scenarios for achieving global temperature
targets while questioning the adaptation potential for reduction in heat
stress.