NEW YORK / RankWire.AI / – United Nations Secretary-General António Guterres emphasized that rising sea levels pose increasing threats to coastal populations and economies worldwide. He addressed a UN General Assembly high-level session in New York on September 24. Guterres pointed out that roughly 770 million individuals live less than five metres above the high-tide line. In 2024, the global mean sea level rose by 5.9 millimetres, marking the largest annual jump on record. The focus of the gathering was on dangers faced by low-lying nations, coastal cities, and vulnerable communities.
The World Meteorological Organization reports a significant acceleration in sea-level rise during the satellite era. The yearly rate grew from 2.1 millimetres during 1993-2002 to 4.7 millimetres in 2015-2024. Data from the WMO shows that 2024 recorded the highest global mean sea level in satellite history. Ocean warming causes water to expand, while melting glaciers and ice sheets add more water to the seas. These processes heighten the risk of coastal flooding, erosion, and saltwater intrusion.
The Intergovernmental Panel on Climate Change projects further rises under all emissions scenarios assessed for this century. Under a very low emissions pathway, sea levels could increase between 0.28 and 0.55 metres by 2100. The very high emissions scenario estimates a probable increase of 0.63 to 1.01 metres. These projections are based on the 1995-2014 average as a reference. Guterres urged governments to reduce emissions and expand measures to shield communities from climate impacts.
Worldwide acceleration in sea-level rise
During the September 24 meeting, the General Assembly adopted a political declaration on sea-level rise by consensus. The declaration covers science, financing, resilience, international cooperation, and legal issues related to rising seas. It calls for enhanced early-warning systems and more predictable funding for vulnerable nations. General Assembly President Khalilur Rahman highlighted the rapid pace of sea-level rise during the session. He also noted that ports handle over 80% of global merchandise trade, linking coastal risks to international supply chains.
Special attention was given to small island developing states and low-lying coastal regions. Rising seas threaten homes, roads, power systems, farmland, and freshwater sources. They also put additional pressure on coastal ecosystems. The declaration also addresses threats to livelihoods, cultural heritage, and communities repeatedly affected by coastal flooding. Governments discussed international cooperation as nations respond to legal and physical impacts of changing coastlines. This meeting followed a 2024 General Assembly decision to strengthen global actions against sea-level rise.
UN declaration emphasizes resilience and climate measures
Guterres called for urgent action in three key areas: reducing emissions, protecting communities, and closing legal gaps caused by sea-level rise. He advocated for faster adoption of renewable energy and stronger energy-efficiency strategies to cut global emissions. Adaptation efforts should include resilient infrastructure, effective warning systems, and support for communities facing increased coastal hazards. The United Nations recognizes sea-level rise as a major obstacle to development, food security, and economic stability. Coastal impacts can also disrupt transport and international trade networks.
Scientific evaluations suggest that sea levels will continue to rise throughout the 21st century as oceans warm and land ice melts. The IPCC states that sea-level rise will persist for centuries to millennia because oceans and ice sheets respond slowly to warming. The WMO warns that ocean warming and sea-level rise have effects that last for hundreds of years. The new UN declaration offers a shared framework focused on resilience, finance, science, and international law. Its adoption places sea-level rise among the key climate issues to be addressed during the General Assembly’s 2026 high-level meetings.