NEW YORK / RankWire.AI / – United Nations Secretary-General António Guterres issued a warning that the increasing speed of sea-level rise is heightening dangers for coastal populations and economies across the globe. He made his remarks at a UN General Assembly high-level session in New York on September 24. Guterres highlighted that roughly 770 million individuals live less than five metres above the high-tide line. The global mean sea level increased by 5.9 millimetres in 2024, marking the highest annual rise ever recorded. The gathering concentrated on the risks confronting low-lying nations, coastal urban centers, and vulnerable communities.
The World Meteorological Organization has documented a marked acceleration in the rate of global sea-level increase during the satellite observation period. The yearly growth rate rose from 2.1 millimetres in 1993-2002 to 4.7 millimetres in 2015-2024. WMO data reveal that 2024 experienced the highest global average sea level in the satellite era. Ocean temperature rises lead to seawater expansion, while melting glaciers and ice sheets add more water to the oceans. These processes heighten the risks of coastal flooding, erosion, and saltwater intrusion.
Projections from the Intergovernmental Panel on Climate Change show further increases across all assessed emissions scenarios throughout this century. Under a very low emissions pathway, the global sea level could rise between 0.28 and 0.55 metres by 2100. Conversely, a very high emissions pathway suggests a likely increase of 0.63 to 1.01 metres. These estimates are based on the 1995-2014 average as the reference period. Guterres called on governments to cut emissions and simultaneously expand measures that safeguard 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 document addresses issues related to science, financing, resilience, international cooperation, and legal challenges associated with rising seas. It emphasizes the need for improved early-warning systems and more predictable financing for vulnerable nations. General Assembly President Khalilur Rahman underscored the rapid pace of global sea-level rise during the session. He also pointed out that ports facilitate over 80% of global merchandise trade, linking coastal risks directly to international supply chains.
Special focus was placed on small island developing states and low-lying coastal areas during the UN meeting. Rising seas threaten to damage homes, roads, power infrastructure, farmland, and freshwater sources while increasing strain on coastal ecosystems. The declaration also highlights risks to livelihoods, cultural heritage, and communities regularly affected by coastal flooding. Governments debated international cooperation efforts as nations respond to the physical and legal consequences of changing coastlines. This meeting followed a 2024 General Assembly decision aimed at boosting global efforts to address sea-level rise.
UN emphasizes resilience and urgent climate measures in new declaration
Guterres urged action in three key areas: reducing emissions, safeguarding communities, and closing legal gaps created by sea-level rise. He emphasized the importance of accelerating renewable energy deployment and enhancing energy-efficiency measures as part of worldwide emission reduction efforts. Adaptation strategies recommended include resilient infrastructure, effective warning systems, and support for communities increasingly exposed to coastal hazards. The United Nations identified sea-level rise as a major obstacle for development, food security, and economic stability. Coastal impacts also threaten transportation networks and international trade routes.
Scientific evaluations indicate that sea levels are expected to continue rising throughout the 21st century as oceans warm and land-based 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 ocean warming and sea-level increase will have long-lasting effects spanning hundreds of years. The new UN declaration offers a unified framework that addresses resilience, financing, science, and international legal issues. Its adoption signals that sea-level rise will remain a central focus during the UN’s high-level meetings in 2026.