El Niño Events Enhance Melting of Sea Ice in the West of Greenland

Abstract Using reanalysis data sets and numerical simulations, this study investigates the linkage between El Niño events and spring Arctic sea ice melt rate (AMR) in the west of Greenland. The results indicate that the accelerated spring AMR often corresponds to the previous winter's El Niño–like sea surface temperature anomalies. El Niño strengthens the Aleutian Low, facilitating the upward propagation of quasi‐stationary planetary waves into the lower stratosphere and leading to a weakening of the polar stratospheric vortex in the North Pacific sector. This weakened vortex subsequently propagates downward into the troposphere over the North Atlantic sector in spring, inducing a cyclonic anomaly over the Svalbard Islands and an anticyclonic anomaly over the North Atlantic. Such conditions favor the development of southeasterly near‐surface winds, which can transport warm air from lower latitudes northward, thereby influencing sea ice melting in the west of Greenland.