NEW YORK / RankWire.AI / – United Nations Secretary-General António Guterres emphasized that the increasing pace of sea-level rise poses serious threats to coastal communities and economies worldwide. During a high-level session at the UN General Assembly in New York on September 24, Guterres noted that approximately 770 million people live less than five metres above the high-tide line. He also highlighted that the global average sea level rose by 5.9 millimetres in 2024, marking the largest annual increase recorded. The session concentrated on the dangers faced by low-lying nations, coastal urban centers, and vulnerable populations.
The World Meteorological Organization has recorded a notable acceleration in the rate of global sea-level increase during the satellite era. Data show an increase from 2.1 millimetres annually in 1993-2002 to 4.7 millimetres in 2015-2024. According to WMO, 2024 saw the highest global mean sea level in the satellite record. Warming of the oceans causes seawater to expand, while melting glaciers and ice sheets contribute additional water. These combined effects heighten the risk of coastal flooding, erosion, and saltwater intrusion into freshwater supplies.
Projections from the Intergovernmental Panel on Climate Change indicate further increases in sea levels across all assessed emissions scenarios this century. Under a very low emissions pathway, the global mean sea level could rise between 0.28 and 0.55 metres by 2100. Conversely, a very high emissions pathway suggests a probable range of 0.63 to 1.01 metres. These estimates reference the 1995-2014 average. Guterres urged governments to accelerate emissions reductions while enhancing measures that shield communities from climate-related impacts.
Worldwide acceleration of sea-level rise
During the September 24 gathering, the General Assembly adopted a political declaration on sea-level rise by consensus. The declaration addresses scientific understanding, funding, resilience strategies, international collaboration, and legal challenges associated with rising seas. It advocates for improved early-warning systems and more predictable financial support for vulnerable nations. General Assembly President Khalilur Rahman pointed out the rapid pace of global sea-level rise during the meeting. He also highlighted that ports facilitate over 80% of international merchandise trade, linking coastal vulnerabilities to global supply chains.
Special attention was given to small island developing states and low-lying coastal regions. Rising seas threaten homes, roads, power infrastructure, farmland, and freshwater sources, intensifying pressure on coastal ecosystems. The declaration also considers risks to livelihoods, cultural heritage, and communities repeatedly affected by coastal flooding. Discussions focused on international cooperation as nations confront physical and legal issues stemming from shifting coastlines. This meeting followed a 2024 General Assembly decision aimed at strengthening global efforts against sea-level rise.
UN initiative emphasizes resilience and climate measures
Guterres called for urgent action in three key areas: reducing greenhouse gas emissions, safeguarding communities, and closing legal gaps caused by sea-level rise. He stressed the need for faster deployment of renewable energy and enhanced energy efficiency as part of comprehensive emission reduction strategies. Adaptation efforts include developing resilient infrastructure, establishing effective warning systems, and providing support to communities facing heightened coastal threats. The United Nations identified sea-level rise as a critical challenge impacting development, food security, and economic stability. Coastal disruptions can also hamper transportation networks and international trade routes.
Scientific evaluations forecast that sea levels will continue to rise throughout the 21st century as ocean temperatures increase and land ice melts. The IPCC states that sea-level rise will persist for centuries to millennia due to the slow response of oceans and ice sheets to warming. WMO has warned that the effects of ocean warming and sea-level increase will endure for hundreds of years. The new UN declaration offers a unified framework encompassing resilience building, financial support, scientific research, and international legal cooperation. Its adoption positions sea-level rise as a central concern in the climate agenda during the General Assembly’s high-level meetings in 2026.