The World Meteorological Organization (WMO) has recently published a report that highlights the alarming threat of global sea-level rise. This poses a severe economic, social, and humanitarian challenge and threatens not only human lives and livelihoods but also coastal farmlands and water reserves. The report identifies India, China, Bangladesh, and the Netherlands as the countries facing the most significant risk from sea-level rise. These countries are not alone, as several large cities on all continents, including Mumbai, New York, and Shanghai, are also threatened by rising sea levels.
The speed at which the largest global ice mass in Antarctica is melting is uncertain. The report notes that the average sea-level rise is further compounded by storm surges and tidal variations, leading to the submergence and loss of coastal settlements, infrastructure, and ecosystems. The impacts of climate change are far-reaching, putting food production and access under increasing pressure in vulnerable regions, and elevating the risks of droughts, floods, and heatwaves.
The report notes that if global mean sea level increases by 0.15 metres over levels in 2020, the population vulnerable to a 100-year coastal flood would rise by almost 20%. Without population change, the exposed population would increase by half at a 0.75-meter rise in mean sea level and by three at a 1.4-meter rise. Around 896 million people, or nearly 11% of the world's population, lived in the Low Elevation Coastal Zone in 2020, and by 2050, that figure may have risen to more than 1 billion.
Urban systems play a critical role in climate resilient development, particularly at the coast. Coastal cities and settlements have a key role in moving towards greater development that is climate resilient, considering escalating climate-compounded risks, including sea-level rise. The report highlights the need for global action to mitigate and adapt to the impacts of sea-level rise.