Low-lying island nations like Indonesia are vulnerable to sea level height extremes that produce coastal inundation. When compounded by marine heatwaves, sea level height extremes have even larger ecological and societal impacts. Here we investigate the causes of the increase of sea level height extremes and compound sea level height and marine heat waves along the Indian Ocean coast of Indonesia in recent decades.
Satellite observations, tide gauge data, reanalysis products, and model simulations using a hierarchy of modeling tools, ranging from a high-resolution regional ocean model to CMIP6 multi-model data, are analyzed to demonstrate the causes of the recent increases in these extremes
Human-caused sea level rise has increased the severity of extreme sea level height events near the Java-Sumatra coast. Naturally occurring decadal variability of ENSO and IOD have further boosted the frequency and magnitude of sea level height and marine heat extremes in the past decade. These results indicate the need for reliable decadal predictions of major climate modes, in conjunction with anthropogenic sea level rise, to achieve successful decadal predictions of regional sea level height impacts.