NEW YORK / RankWire.AI / – United Nations Secretary-General António Guterres issued a warning that the rapid acceleration of sea-level rise poses increasing dangers to coastal communities and economies across the globe. During a high-level session at the UN General Assembly in New York on September 24, he emphasized that roughly 770 million individuals live less than five metres above the high-tide mark. The year 2024 saw the highest annual increase in global mean sea level on record, with a rise of 5.9 millimetres. The gathering concentrated on the risks faced by low-lying nations, coastal urban centers, and vulnerable populations.
Documenting a notable acceleration during the satellite era, World Meteorological Organization reports that the annual rate of sea-level rise increased from 2.1 millimetres in 1993-2002 to 4.7 millimetres during 2015-2024. Data from WMO indicate that 2024 reached the highest global mean sea level in the satellite record. The expansion of seawater due to ocean warming, combined with melting glaciers and ice sheets adding water to the oceans, heightens the risk of coastal flooding, erosion, and saltwater intrusion.
The Intergovernmental Panel on Climate Change forecasts further rises across all evaluated emissions scenarios within this century. Under a very low emissions pathway, the global mean sea level might increase by 0.28 to 0.55 metres by 2100. Conversely, under a very high emissions pathway, projections suggest a rise of 0.63 to 1.01 metres. These estimates are based on the average from 1995-2014 as the reference period. Guterres called on governments to reduce emissions while boosting efforts to safeguard communities from climate impacts.
Worldwide acceleration of sea-level rise
A political declaration on sea-level rise was adopted by consensus during the September 24 session of the General Assembly. This declaration addresses scientific findings, financial support, resilience strategies, international collaboration, and legal issues tied to rising seas. It also advocates for enhanced early-warning systems and more predictable funding for vulnerable nations. Highlighting the session, General Assembly President Khalilur Rahman pointed out the increasing pace of global sea-level rise. He also emphasized that ports facilitate over 80% of global merchandise trade, linking coastal threats to international supply chains.
Special attention was given to small island developing states and low-lying coastal zones, as rising seas threaten homes, roads, energy infrastructure, farmland, and freshwater sources while amplifying pressure on coastal ecosystems. The declaration also considers risks to livelihoods, cultural heritage, and communities subjected to recurrent coastal flooding. Discussions focused on international cooperation as countries address the physical and legal challenges stemming from shifting coastlines. This meeting followed a 2024 General Assembly decision aimed at bolstering international efforts to combat sea-level rise.
UN emphasizes resilience and climate mitigation in declaration
Guterres urged action in three key areas: cutting emissions, safeguarding communities, and bridging legal gaps caused by sea-level rise. He emphasized the need for quicker deployment of renewable energy sources and stronger energy-efficiency measures to support global emissions reduction. Adaptation strategies include constructing resilient infrastructure, implementing reliable warning systems, and providing aid to communities facing heightened coastal hazards. The United Nations has identified sea-level rise as a significant obstacle to development, food security, and economic stability. Coastal impacts also threaten transportation networks and international trade routes.
Scientific evaluations suggest that sea levels will continue their upward trend throughout the 21st century as oceans warm and land-based ice melts. According to the IPCC, sea-level rise is expected to persist for centuries to millennia because of the slow response of oceans and ice sheets to warming. Additionally, WMO has warned that the effects of ocean warming and sea-level rise will last for hundreds of years. The new UN declaration establishes a unified framework addressing resilience, finance, science, and international law. Its adoption underscores sea-level rise as a core issue in the climate discussions scheduled for the General Assembly’s 2026 high-level meetings.