Records broken for ocean heat, sea level rise, glacier retreat… 2023 concluded the hottest decade on record, pushing the planet “to the brink of the abyss”, the UN warned on Tuesday.
A new report from the World Meteorological Organization (WMO), a UN agency, shows that records have been broken, and in some cases “shattered”, for greenhouse gas levels, temperatures surface area, heat content and ocean acidification, sea level rise, Antarctic sea ice extent and glacier retreat.
The planet is “on the brink of collapse” while “fossil fuel pollution causes unprecedented climate chaos,” warned UN Secretary General António Guterres.
“There is still time to throw a lifeline to people and the planet”, according to him, but we must act “now”.
The report confirms that 2023 was the hottest year on record, with an average global surface temperature 1.45°C above the pre-industrial baseline.
“Every fraction of a degree of global warming has an impact on the future of life on Earth,” warned the UN chief.
” Red alert “
“The climate crisis is THE defining challenge facing humanity and is inextricably linked to the inequality crisis, as evidenced by growing food insecurity, population displacement and loss of biodiversity,” added the Secretary General. of WMO, Celeste Saulo.
Heat waves, floods, droughts, wildfires and the rapid intensification of tropical cyclones are sowing “misery and chaos”, disrupting the daily lives of millions of people and inflicting economic losses worth billions of dollars, alerts the WMO.
It is also the hottest decade (2014-2023) ever observed, exceeding the 1850-1900 average by 1.20°C.
The long-term rise in global temperature is due to the increase in the concentration of greenhouse gases in the atmosphere, which reached record levels in 2022.
The arrival of the El Niño phenomenon in mid-2023 also contributed to the rapid rise in temperatures, according to the WMO.
According to Ms. Saulo, “we have never been so close – although temporarily for the moment – to the lower limit set at 1.5 ° C in the Paris Agreement on climate change”.
“The global meteorological community is warning the whole world and sounding the alarm: we are on red alert,” she assured.
“What we have witnessed in 2023, in particular the unprecedented warming of the oceans, the retreat of glaciers and the loss of sea ice in Antarctica, causes the greatest concern,” observed Ms. Saulo.
Oceans and glaciers
Last year, nearly a third of the world’s oceans were in the grip of a marine heatwave. By the end of 2023, more than 90% of the world’s oceans had experienced heat waves at some point during the year, according to the WMO.
The increasing frequency and intensity of marine heatwaves has profound negative impacts on marine ecosystems and coral reefs.
Furthermore, the average sea level on a global scale reached a record level in 2023, which reflects the continued warming of the oceans (thermal expansion) as well as the melting of glaciers and ice sheets.
A worrying sign is that the rate of rise of this average level over the last decade (2014-2023) is more than twice that of the first decade of the satellite era (1993-2002).
Landmark glaciers across the planet have suffered the largest retreat on record since 1950, following extreme melting in western North America and Europe, according to preliminary data.
There is, however, “a glimmer of hope”, according to the WMO: renewable energy production capacities in 2023 increased by almost 50% year-on-year, the highest rate observed in the last two decades. .