Tropical cyclone (TC) translation speed often affects the time of strong wind attacks and precipitation accumulation in the areas that TCs pass through. Therefore, the trend of TC translation speed has important implications for TC-related risks in the current and future climate. In this paper, the trends of TC translation speed over the Western North Pacific (WNP) from 1980 to 2018 are analyzed, and TC lifetime maximum intensity (LMI) is proposed as a factor related to the interdecadal change of translation speed. During the periods with accurate data, 1980–1997 shows a decreasing trend in TC translation speed while an increasing trend was found in 1998–2018. The main lifetime period contributing to a TC translation speed change is before the occurrence of the LMI. The change in the trend is related to both the TC’s characteristics itself and the environmental factors. For the period 1998–2018, an increasing trend of TC intensity has a significant influence on the trend of translation speed. For the environmental factors, a trend of east wind enhancement at and above 500 hPa as the steering flow is found mostly correlated in the active TC region of the WNP with westward translation before reaching LMI, accompanied by a weakening trend of 200–850 hPa vertical wind shear, and an increasing trend of potential intensity.

Understanding of the El Niño phenomenon is improving and several studies have considered the dynamics of El Niño diversity, however, the important role of tropical cyclones has not been reported. Here we show a clear influence of tropical cyclones over the western North Pacific on the spatial pattern of El Niño: By changing the Walker circulation and equatorial thermocline, strong (weak) accumulated cyclone energy helps to shift the center of strongest sea surface temperature anomalies three months later to the equatorial eastern (central) Pacific. The greater number of central-Pacific El Niño events after 1999/2000 may be associated with weaker accumulated cyclone energy in this period. A modified physically based empirical model (ACE+SST model) for predicting El Niño spatial patterns is constructed that captures well the spatiotemporal characteristics of El Niño events. Taking into account the key influence of western North Pacific tropical cyclones on El Niño diversity will improve our understanding and prediction of El Niño.