During the opening of a high-level meeting to address this challenge, the head of the organization called for drastic action to reduce emissions and adapt to rising waters.

Low-lying coastal areas, where an estimated 900 million people live, face intense storm surges, erosion and flooding, contaminated fresh water, ruined crops, damaged infrastructure, destroyed biodiversity and decimated economies, he warned.

“This is what climate injustice looks like,” said Guterres, lamenting these effects in developing nations such as Bangladesh, Panama or Senegal.

According to the high representative, the consequences of rising sea levels could be worse if action is not taken quickly. “For some this could be existential: entire islands lost; coastal communities destroyed as land becomes uninhabitable and unsecurable,” he added at the meeting called in the context of the General Assembly’s high-level week.

At the same time, mass displacement would increase pressure on scarce resources elsewhere; and global trade, food systems and supply chains would be affected as ports, agricultural land and fisheries are damaged.

“Rising sea levels will not only change coastlines, but also economies, politics and security,” said Guterres.

Among other actions, the UN chief urged a rapid and fair phase-out of fossil fuels, particularly in the G20 countries, responsible for around 80 percent of emissions.

He also called for increased funding for the upcoming COP29 along with significant contributions to the new Loss and Damage Fund, as a step towards climate justice.

Developed nations must double adaptation finance to at least $40 billion a year by 2025, and demonstrate how they will close the adaptation finance gap, he insisted.

“We need to reform multilateral development banks to make them bigger, bolder and able to offer much more affordable finance to developing countries,” he added.

ef/ro/ebr