What Controls ENSO Teleconnection to East Asia? Role of Western North Pacific Precipitation in ENSO Teleconnection to East Asia

Abstract

There are distinct impacts of anomalous tropical forcings associated with the El Nino-Southern Oscillation (ENSO) on the climate in East Asia via an atmospheric teleconnection. In this study, the intrawinter changes in the atmospheric teleconnection and its regional impacts associated with ENSO are investigated using data from 386 weather stations throughout Korea, China, and Japan. It has recently been shown that the relative roles of western North Pacific (WNP) and equatorial central Pacific (CP) precipitation anomalies play an important role in determining the ENSO teleconnection in the North Pacific. Here we show that the ENSO impacts over East Asia can also be largely explained by a combination of WNP and equatorial CP forcing. Further, the diverse regional impacts among different ENSO events can be explained to a large extent by the relative roles of the WNP and equatorial CP precipitation. Analyses from state-of-the-art coupled model simulations from the Coupled Model Intercomparison Project Phase 5 archive support these observational arguments.