Paris – Concentrations of greenhouse gases in the atmosphere will reach record highs by 2023, the United Nations warned on Monday, saying countries are “miles short” of what is needed to curb climate change. devastating global warming.
Levels of the three major greenhouse gases – carbon dioxide, methane and nitrous oxide – all rose again last year, according to the World Meteorological Organization, the UN’s weather and climate agency.
Carbon dioxide was accumulating in the atmosphere faster than ever, up more than 10 percent in two decades, it added.
And a separate UN report shows that it is barely making a dent in the 43 percent emissions reduction needed by 2030 to avoid the worst of global warming.
Current action would only lead to a 2.6 percent reduction this decade compared to 2019 levels.
“The report’s findings are stark but not surprising: Current national climate plans fall far short of what is needed to prevent global warming from crippling every economy and destroying billions of lives and livelihoods in every country,” says UN climate chief Simon Stiell.
The two reports come just weeks before the United Nations COP29 climate summit in Azerbaijan and as countries prepare to submit updated national climate plans in early 2025.
“Braver” plans to reduce the pollution causing warming will need to be drawn up now, Stiell said, calling for the end of “the age of inadequacy.”
Under the 2015 Paris Climate Agreement, countries said they would limit global warming to “well below” two degrees Celsius above average levels measured between 1850 and 1900 – and 1.5 degrees Celsius if possible.
But so far their actions have failed to meet this challenge.
Under existing national commitments, 51.5 billion tons of CO2 and its equivalent in other greenhouse gases would be emitted in 2030 – levels that “would guarantee a human and economic train wreck for every country, without exception,” Stiell said.
As long as emissions continue, greenhouse gases will continue to build up in the atmosphere, causing global temperatures to rise, the WMO said.
Last year, global temperatures on land and sea were the highest in records dating back to 1850, it added.
WMO chief Celeste Saulo said the world is “clearly on the wrong track” to meet the Paris Agreement target, adding that record greenhouse gas concentrations “should ring alarm bells among decision makers.”
“CO2 is accumulating in the atmosphere faster than ever before during human existence,” the report said, adding that current levels of CO2 in the atmosphere were 51 percent higher than those of the pre-industrial era.
The last time Earth experienced a comparable concentration of CO2 was three to five million years ago, when temperatures were two to three degrees Celsius warmer and sea levels were 20 meters higher than today, the report said.
Given how long CO2 remains in the atmosphere, current temperature levels will persist for decades, even if emissions quickly drop to net zero.
In 2023, CO2 concentrations were 420 parts per million (ppm), methane 1,934 parts per billion and nitrous oxide 336 parts per billion.
CO2 is responsible for about 64 percent of the warming effect on the climate.
The annual increase of 2.3 ppm marked the twelfth year in a row of an increase of more than 2 ppm – an increase driven by “historically large CO2 emissions from fossil fuels in the 2010s and 2020s,” the report said.
Just under half of CO2 emissions remain in the atmosphere, while the rest is absorbed by ocean and land ecosystems.
Climate change itself could soon “cause ecosystems to become greater sources of greenhouse gases,” WMO deputy chief Ko Barret warned.
“Forestfires could release more CO2 into the atmosphere, while the warmer ocean may absorb less CO2. Consequently, more CO2 could remain in the atmosphere, which would accelerate global warming.
