Intensification of Summer Monsoon Frontal Precipitation in East Asia under Human-Induced Global Warming
As the lifeblood of East Asia (EA), summer monsoon precipitation fuels agriculture, industry, and everyday life. Yet, its dark side emerges when severe events batter densely populated regions, causing havoc and disaster. In recent years, South Korea, China, and Japan have all faced the wrath of extreme precipitation events. As our climate changes, we are left to wonder: Are these events the new norm? How will the EA summer monsoon precipitation system adapt? This study delves into the complex narrative of summer precipitation in EA – a tale of cyclones, fronts, and other weather systems. We zoom into the role of stationary front-induced precipitation, a key character that shapes more than 30% of EA’s summer rainfall narrative. Sifting through data from 1958–2015, we have observed a dramatic 19.8% surge in the intensity of frontal rainfall. With the Community Earth System Model Large Ensemble simulations as our guide, we have untangled the role of anthropogenic warming, revealing it as the primary cause behind the amplified EA summer frontal rainfall. Behind this intensification, two culprits emerge: the amplified western North Pacific subtropical high and increased water vapor convergence. Our findings suggest that human-induced global warming is radically reshaping the EA summer monsoon, supercharging its precipitation system. This transformation is likely to continue, potentially redefining the future of rainfall in EA.