Geneva: Global sea levels are rising at more than double the pace they did in the first decade of measurements in 1993-2002 and hit a new record high last year, the World Meteorological Organization said on Friday, warning that the trend would continue for millennia.
Extreme glacier melt and record ocean heat levels - which cause water to expand - contributed to an average rise in sea levels of 4.62mm a year between 2013-2022, the U.N. agency said in a major report detailing the havoc of climate change. That is about double the pace of the first decade on record, 1993-2002, leading to a total increase of over 10 cm since the early 1990s.
"We have already lost this melting of glaciers game and sea level rise game so that's bad news," WMO Secretary-General Petteri Taalas told a press conference. That is because such high levels of greenhouse gases have already been emitted that waters would continue to rise for "thousands of years".
Rising sea levels threaten some coastal cities and the very existence of low-lying states such as the island of Tuvalu - which plans to build a digital version of itself in case it is submerged.
The annual report, released a day ahead of Earth Day, also showed that sea ice in Antarctica receded to record lows last June and July. Oceans were the warmest on record, with around 58% of their surfaces experiencing a marine heatwave, it said.
Some 15,000 people died during Europe's heatwaves last year, it stated.
Taalas said such extreme weather patterns would continue into the 2060s no matter what steps we take to reduce emissions. But he said there was still a chance to turn around things afterwards.
"The good news would be that we would be able to phase out this negative trend and even reach the 1.5 degrees (Celsius)limit," he said, noting more ambitious climate plans from G7 countries that could enable the world to meet the 2015 Paris temperature target.
Overall, the WMO said 2022 ranked as the fifth or sixth warmest year on record with the mean global temperature 1.15 degrees Celsius above the pre-industrial average, despite the cooling impact of a three-year La Nina climatic event.
Climate scientists have warned that the world could breach a new average temperature record in 2023 or 2024, fuelled by climate change and the anticipated return of warming El Nino conditions.
