Four key climate change indicators all set new record highs in 2021, the United Nations said Wednesday, warning that the global energy system was driving humanity towards catastrophe.
Greenhouse gas concentrations, sea level rise, ocean heat and ocean acidification all set new records last year, the UN’s World Meteorological Organization (WMO) said in its “State of the Global Climate in 2021” report.
“The global energy system is broken and bringing us ever closer to climate catastrophe.”
WMO chief Petteri Taalas said the war in Ukraine had been overshadowing climate change, which “is still the biggest challenge we are having as mankind”.
The report confirmed the past seven years were the top seven hottest years on record.
Even so, it was still one of the warmest years ever recorded, with the average global temperature in 2021 about 1.11 degrees Celsius above the pre-industrial level.
“All major climate indicators are quite frankly heading in the wrong direction and without much greater ambition and urgency, we are about to lose the narrow window of opportunity to keep the 1.5-degree goal alive,” Guterres’ climate action advisor Selwin Hart told a press conference.
“The heat trapped by human-induced greenhouse gases will warm the planet for many generations to come. Sea level rise, ocean heat and acidification will continue for hundreds of years unless means to remove carbon from the atmosphere are invented,” he said.
Four key indicators of climate change “build a consistent picture of a warming world that touches all parts of the Earth system”, the report said.
Data indicate they continued to increase in 2021 and early 2022, the report said.
Global mean sea level reached a new record high in 2021, rising an average of 4.5 millimetres per year throughout 2013 to 2021, the report said.
Taalas said the melting of glaciers would raise sea levels for hundreds or thousands of years to come, due to CO2 concentrations in the atmosphere.
– Price of failure –
And it is expected the upper 2,000 metres of the ocean will continue to warm in the future — “a change which is irreversible on centennial to millennial timescales”, said the WMO.
The UN’s Intergovernmental Panel on Climate Change concluded with “very high confidence” that open ocean surface acidity is at the highest “for at least 26,000 years”.
“We are now heading 2.5 to three degrees warming instead of 1.5, which would be best for our future.
Originally published as Climate change indicators hit record highs in 2021: UN