NEW YORK / RankWire.AI / – United Nations Secretary-General António Guterres issued a warning that the increasing rate of sea-level rise poses escalating threats to coastal populations and their economies worldwide. Addressing a high-level gathering at the UN General Assembly in New York on September 24, Guterres emphasized that approximately 770 million individuals live within five metres of the high-tide mark. The year 2024 saw the global average sea level climb by 5.9 millimetres, marking the highest annual rise ever recorded. The assembly concentrated on the dangers confronting low-lying nations, urban coastal regions, and vulnerable communities.
The World Meteorological Organization has documented a marked acceleration in the pace of global sea-level increase since the satellite era began. The yearly growth rate surged from 2.1 millimetres during 1993-2002 to 4.7 millimetres in the period of 2015-2024. Data from WMO demonstrate that 2024 experienced the highest global mean sea level within the satellite record. Warming of the oceans causes seawater expansion, and the melting of glaciers and ice sheets contributes additional water to the oceans, thereby heightening the risk of coastal flooding, erosion, and saltwater intrusion.
Projections from the Intergovernmental Panel on Climate Change indicate that sea levels will continue to rise across all assessed emissions scenarios throughout this century. Under a very low emissions pathway, the global mean sea level could increase between 0.28 and 0.55 metres by 2100, whereas a very high emissions scenario suggests a likely range of 0.63 to 1.01 metres. These estimates are based on the average from 1995-2014. Guterres called on governments to not only reduce emissions but also expand efforts to shield communities from the adverse effects of climate change.
Global acceleration in sea-level rise highlighted
During the September 24 session, the General Assembly unanimously adopted a political declaration concerning sea-level rise, addressing critical issues related to scientific understanding, financial support, resilience strategies, international collaboration, and legal frameworks associated with rising seas. The declaration also advocates for enhanced early-warning systems and more predictable funding to assist vulnerable nations. General Assembly President Khalilur Rahman underscored the rapid increase in global sea levels during the meeting, noting that since over 80% of worldwide merchandise trade passes through ports, coastal risks directly affect global supply chains.
Special attention was given to small island developing states and low-lying coastal regions, as rising seas threaten to damage homes, infrastructure, agricultural land, freshwater sources, and increase the strain on coastal ecosystems. The declaration further emphasizes the risks to livelihoods, cultural heritage, and communities subjected to recurrent coastal flooding. Countries discussed the importance of international cooperation in tackling both physical and legal challenges resulting from changing coastlines, building on a 2024 General Assembly decision aimed at bolstering global efforts against sea-level rise.
UN focus on adaptation and climate mitigation
Guterres emphasized the necessity of action in three key domains: reducing greenhouse gas emissions, safeguarding communities, and closing legal gaps exacerbated by sea-level rise. He urged a swift expansion of renewable energy sources and stronger energy-efficiency policies as vital components of the broader effort to cut emissions globally. Adaptation strategies include developing resilient infrastructure, establishing effective warning systems, and supporting communities increasingly vulnerable to coastal hazards. The United Nations has identified sea-level rise as a significant challenge impacting development, food security, and economic stability, with coastal impacts also threatening transportation networks and international trade.
Scientific evaluations indicate that sea levels are expected to continue their upward trend through the 21st century as oceans warm and land-based ice melts. The IPCC states that sea-level rise will persist for centuries to millennia because oceans and ice sheets respond slowly to climate warming. WMO has also warned that ocean warming and sea-level increase will produce effects that last for hundreds of years. The new UN declaration offers a unified framework that covers resilience, financing, science, and international legal issues. Its adoption signifies that sea-level rise will remain a core focus among the major climate issues addressed in the General Assembly’s high-level meetings in 2026.