Robust future changes in meteorological drought in CMIP6 projections
despite uncertainty in precipitation
Abstract
Quantifying how climate change drives drought is a priority to inform
policy and adaptation planning. We show that the latest Coupled Model
Intercomparison Project (CMIP6) simulations project coherent regional
patterns in meteorological drought for two emissions scenarios to 2100.
We find robust projected changes in seasonal drought duration and
frequency (robust over >45% of the global land area),
despite a lack of agreement across models in projected changes in mean
precipitation (24% of the land area). Future drought changes are larger
and more consistent in CMIP6 compared to CMIP5. We find regionalised
increases and decreases in drought duration and frequency that are
driven by changes in both precipitation mean and variability.
Conversely, drought intensity increases over most regions but is not
simulated well historically by the climate models. The more robust
projections of meteorological drought compared to mean precipitation in
CMIP6 provides significant new opportunities for water resource
planning.