Larger spatial footprint of wintertime total precipitation extremes in a
The simultaneous occurrence of extremely wet winters at multiple
locations in the same region can contribute to widespread flooding and
associated socio-economic losses. However, the change in the spatial
extent of precipitation extremes is largely overlooked in climate change
assessments. Employing new multi-thousand-year climate model
simulations, we show that under both 2.0°C and 1.5°C warming scenarios,
wintertime precipitation extreme extents would increase over about
80-90% of the Northern Hemisphere. Stabilising at 1.5°C rather than 2°C
would reduce the average magnitude of the increase by 1.6-2 times.
According to the climate model, the increased extents are caused by
increases in precipitation intensity increasing rather than changes in
the spatial organisation of the events. Relatively small percentage
increases in precipitation intensities (e.g., by 4%) can drive
disproportionately larger, by 1-2 orders of magnitude, growth in the
spatial extents (by 97%).