Global Mean Sea Level Changes to ENSO-Related Regional Land Water Storage

The 2010–2011 La Niña caused a sharp but temporary drop in global sea level due to increased rainfall and terrestrial water storage primarily in Australia. However, whether similar responses occurred in other La Niña events remains unclear. Here we investigate analogous impacts during other El Niño-Southern Oscillation (ENSO) events using available sea level height observations during 1993–2022. We find that ENSO consistently drives changes in terrestrial and oceanic precipitation, land water storage, and sea surface salinity. These changes cause temporary global sea level declines during La Niña and increases during El Niño, with the most pronounced variations occurring during the build-up phase of ENSO. A strong negative relationship between terrestrial precipitation and global mean sea level underscores the critical role of ENSO-driven global water redistribution. Northern South America consistently experienced water storage gains during La Niña and declines during El Niño, whereas water storage changes in Australia were inconsistent.