摘要:Collaboration of interannual variabilities and the climate mean state determines the type of El Niño. Recent studies highlight the impact of a La Niña-like mean state change, which acts to suppress the convection and low-level convergence over the central Pacific, on the predominance of central Pacific (CP) El Niño in the most recent decade. However, how interannual variabilities affect the climate mean state has been less thoroughly investigated. Using a linear shallow-water model, the effect of decadal changes of air-sea interaction on the two types of El Niño and the climate mean state over the tropical Pacific is examined. It is demonstrated that the predominance of the eastern Pacific (EP) and CP El Niño is dominated mainly by relationships between anomalous wind stresses and sea surface temperature (SST). Furthermore, changes between air-sea interactions from 1980–98 to 1999–2011 prompted the generation of the La Niñalike pattern, which is similar to the background change in the most recent decade.
关键词:air-sea interaction; EP El Niño; CP El Niño; La Niña-like mean state change