Spatially Distinct Effects of Two El Niño Types on Summer Heat Extremes in China

Changes in the activity of summer high-temperature extremes (HTEs) over many regions are linked with the El Niño-Southern Oscillation. However, how the HTEs respond to different flavors of El Niño remains unclear. Using observational analyses, we show that summer HTEs in China during eastern Pacific (EP) and central Pacific (CP) types of El Niño exhibit different spatial patterns. EP (CP) El Niño is significantly correlated with summer HTEs over South China (Yangtze River valley). These relationships can be attributed to the modulation of the western North Pacific subtropical high and the East Asian jet stream. EP (CP) El Niño events are accompanied by westward (eastward) extension of the western North Pacific subtropical high and equatorward (poleward) movement of the jet stream over East Asia (Pacific). During EP (CP) El Niño episodes, the westward (eastward) and equatorward (poleward) displacements of upper-tropospheric anticyclone over the western North Pacific coincide with the subsidence anomaly over South China (Yangtze River valley).