Extreme sea level rise along the Indian Ocean coastline: observations and 21st century projections

Abstract Anthropogenic sea-level rise poses challenges to coastal areas globally. The combined influence of rising mean sea level (MSL) and storm surges exacerbate the extreme (ESL). Increasing ESL a major challenge for climate change adaptation nearly 2.6 billion inhabitants in Indian Ocean region. Yet, knowledge about past occurrences its progression is limited. Combining multiple tide-gauge satellite-derived data, we show that has become more frequent, longer-lasting intense along coastlines. We detect 2–3-fold increase occurrence, with higher risk Arabian Sea coastline Islands. Our results reveal MSL primary contributor (more than 75%), additional contribution from intensifying tropical cyclones. A two-fold detected an 0.5 °C warming relative pre-industrial levels. Utilizing likely range (17th–83rd percentile as spread) Intergovernmental Panel on Climate Change projections considerable inter-model spread, region will be exposed annually present-day 100 year event by 2100, irrespective greenhouse-gas emission pathways, 2050 under moderate-emission-mitigation-policy scenario. study provides robust regional estimate MSL, which important policies.