Sea-level rises accelerating while last eight years warmest on record, UN report warns

World Meteorological Organisation releases annual report as Cop27 opens in Egypt

The past eight years “are on track to be the eight warmest on record, fuelled by ever-rising greenhouse gas concentrations and accumulated heat”, the latest assessment by the World Meteorological Organization (WMO) has found.

The WMO warns that sea-level rises are accelerating and many glaciers have passed a tipping point, with melting set to continue for hundreds, if not thousands, of years with major implications for water security.

The year 2022 was one of “extreme heatwaves, drought and devastating flooding that has affected millions and cost billions”, it adds.

The State of the Global Climate report, issued on the opening day of Cop27 in Egypt, is the definitive annual assessment of the Earth’s climate. A series of other UN reports issued in the past fortnight confirmed the planet is heading for potentially catastrophic warming of 2.5 degrees this century and that all major greenhouse gases are at record levels in the atmosphere.


The telltale signs and impacts of climate change are becoming more dramatic, the WMO adds. “The rate of sea level rise has doubled since 1993. It has risen by nearly 10mm since January 2020 to a new record high this year. The past two-and-a-half years alone account for 10 per cent of the overall rise in sea level since satellite measurements started nearly 30 years ago,” it finds.

The report shows the tipping point for some glaciers in the Alps has been passed; it is too late to save them and to prevent them adding to rising sea levels. The Greenland ice sheet lost mass for the 26th consecutive year, and it rained (rather than snowed) there for the first time in September.

Some of the world’s most famous glaciers – including in the Dolomites in Italy, the Yosemite and Yellowstone parks in the United States, and Mount Kilimanjaro in Tanzania – could disappear within 30 years due to global warming, whatever the temperature rise scenario, a Unesco report said on Friday.

The UN cultural agency, which monitors 18,600 glaciers across 50 of its world heritage sites, said one-third of them were set to disappear by 2050 regardless of applied climate projections - because of current levels of warming.

The global mean temperature in 2022 is estimated to be about 1.15 degrees above the 1850-1900 pre-industrial average, the WMO confirms.

A rare triple-dip cooling La Niña means that 2022 is likely to “only” be fifth or sixth warmest. However, this does not reverse the long-term trend; it is only a matter of time until there is another warmest year on record.

WMO secretary general Petteri Taalas said: “The greater the warming, the worse the impacts. We have such high levels of carbon dioxide in the atmosphere now that the lower 1.5 degree [target] of the Paris Agreement is barely within reach.”

UN secretary general Antonio Guterres said in response to the WMO findings: “As Cop27 gets under way, our planet is sending a distress signal. The latest State of the Global Climate report is a chronicle of climate chaos.”

As the WMO shows so clearly, he noted, “change is happening with catastrophic speed – devastating lives and livelihoods on every continent”.

“The past eight years have been the warmest on record, making every heatwave more intense and life-threatening, especially for vulnerable populations,” he added.

Sea levels are rising at twice the speed of the 1990s – posing an existential threat for low-lying island states, and threatening billions of people in coastal regions, Mr Guterres noted, adding he believed glacier melt was jeopardising water security for whole continents.

“We must answer the planet’s distress signal with action – ambitious, credible climate action. Cop27 must be the place – and now must be the time,” he said.

Prof Mike Meredith, oceanographer and science leader at the British Antarctic Survey, said: “The messages in this report could barely be bleaker – all over our planet, records are being shattered as different parts of the climate system begin to break down.

“The loss of ice is especially alarming – the impacts on people, societies and economies are huge, and it’s only going to get worse unless major action takes place straight away. If this doesn’t focus the minds of the global leaders at Cop27, I don’t know what will.”

Kevin O'Sullivan

Kevin O'Sullivan

Kevin O'Sullivan is Environment and Science Editor and former editor of The Irish Times