United Nations warns rising sea levels threaten 770 million people

The United Nations has issued warnings regarding rising sea levels, which threaten the livelihoods of approximately 770 million people living less than five meters above the high-tide line. Between 2014 and 2023, the global mean sea level rose by an average of 4.7 millimeters per year, with a record increase of 5.9 millimeters recorded in 2024.

Climate change, driven by human activity, is the primary cause. The rise is attributed to the melting of glaciers and ice sheets, as well as thermal expansion, where warming oceans occupy more space. Oceans currently absorb about 90% of the planet's excess heat.

Projections for the year 2100 vary by scenario. In an optimistic outlook, sea levels may rise by 0.55 meters. In worst-case scenarios, the increase could exceed one meter, and under high greenhouse gas emission scenarios, there is a small but significant possibility of a rise approaching two meters.

The consequences extend beyond coastal flooding to include the salinization of freshwater wells and agricultural land, threats to food and water security, and damage to critical infrastructure such as hospitals and schools. These shifts also impact human rights, economic development, and industries like fishing and tourism.