International Desk

Sea levels rose faster than expected around the world in 2024 – the Earth’s hottest year on record, according to new findings from the United States’ NASA space agency, which attributed the rise to warming oceans and melting glaciers.

“With 2024 as the warmest year on record, Earth’s expanding oceans are following suit, reaching their highest levels in three decades,” NASA’s Nadya Vinogradova Shiffer, head of physical oceanography programmes and the Integrated Earth System Observatory, said on Thursday.

The NASA-led analysis found that last year's rate of sea level rise was 0.59 centimeters per year, higher than the expected 0.43 centimeters per year.

"Every year is a little bit different, but what's clear is that the ocean continues to rise, and the rate of rise is getting faster and faster," said Josh Willis, a sea level researcher at NASA's Jet Propulsion Laboratory in Southern California.

The unexpected increase was attributed to an unusual amount of ocean warming, combined with meltwater from land-based ice, such as glaciers, NASA explained.

In recent years, about two-thirds of sea level rise was driven by the addition of water from melting ice sheets and glaciers, with the remaining third attributed to thermal expansion of seawater. However, in 2024, these contributions were reversed, with two-thirds of the rise coming from thermal expansion, according to NASA.

Since the satellite record of ocean height began in 1993, the rate of annual sea level rise has more than doubled. In total, global sea levels have risen by 10 centimeters since 1993, according to NASA.

Rising sea levels are among the consequences of human-induced climate change, and oceans have risen in line with the increase in the Earth’s average surface temperature – a change which itself is caused by greenhouse gas emissions.

NASA said trends from recent years showed additional water from land due to melting ice sheets and glaciers to be the biggest contributor, accounting for two-thirds of sea level rise.

In 2024, however, the increased rise in sea levels was largely driven by the thermal expansion of water – when ocean water expands as it warms – which accounts for about two-thirds of the increase.

The UN has warned of threats to vast numbers of people living on islands or along coastlines due to rising sea levels, with low-lying coastal areas of India, Bangladesh, China and the Netherlands flagged as areas of particular concern, as well as island nations in the Pacific and Indian Oceans.