Extreme precipitation over East Asia under 1.5 °C and 2 °C global warming targets: a comparison of stabilized and overshoot projections

Abstract

Highly populated East Asia is vulnerable to extreme precipitation.Here, we useCommunity Earth SystemModel low-warming simulations to examine how extreme precipitation eventsmay change in East Asia under the Paris Agreement global warming targets. The frequency and intensity of extreme precipitationwill increasemarkedly over East Asia in thewarmer climates. Limiting end-of-century warming to 1.5 °C, in comparisonwith 2 °C,will reduce the risks of extreme precipitation frequency and intensity in East Asia by 26%–31%,with the greatest reductions (38%–54%) in Japan. A brief overshoot of the 1.5 °C target would affectMongolia, theKorean Peninsula and Japan from the aspects of regional average.More than 25%of the increase in the frequency and intensity of extreme precipitation in these regions can be avoided during the end of the 21st century (2081–2100) if there is no temperature overshoot, according to the best estimate. Verticalmoisture advection is themain contributor to changes in precipitation-minus-evaporation in East Asia in thewarmer climates. The increased low-level specific humidity and cyclonic circulation changes are the dominant thermodynamic and dynamical processes that contribute to the increase of precipitation over SouthChina and Japan.Ourwork suggests that limiting warming to 1.5 °Cwithout overshoot is beneficial to minimizing the impacts associatedwith precipitation extremes across East Asia.