Longer‐ and Slower‐Moving Contiguous Heatwaves Linked to El Niño

Abstract

Abstract Although it is known that the frequency and intensity of heatwaves are affected by the El Niño–Southern Oscillation (ENSO), unknown are the ENSO modulations on the moving properties (e.g., moving distance and speed) of spatiotemporally contiguous heatwaves. Here, we investigate the relationship between ENSO and the moving patterns of contiguous heatwaves. We show that contiguous heatwaves are likely more frequent, more persistent, and longer‐traveling, but slower‐moving during El Niño than La Niña episodes. The differences in the tropical contiguous heatwaves between El Niño and La Niña are influenced by persistent high‐pressure anomalies. During the following summers, El Niño can induce anomalous atmospheric circulation characterized by an intensified subsidence over the western North Pacific and ascending motion over the tropical Indian and Pacific Oceans. These features provide favorable conditions for the occurrence and maintenance of contiguous heatwaves.

Keywords

• spatiotemporally contiguous heatwaves
• El Niño‐Southern Oscillation (ENSO)
• longer‐traveling
• longer‐lasting
• slower‐moving