Greenhouse gases hit record high in 2022: UN
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Carbon dioxide accounts for about 64 per cent of the warming effect on the climate.
PHOTO: NYTIMES
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GENEVA - Greenhouse gas concentrations in the atmosphere hit new record highs in 2022, with no end in sight to the rising trend, the United Nations warned on Wednesday.
The UN’s World Meteorological Organisation (WMO) said levels of the three main greenhouse gases – the climate-warming carbon dioxide (CO2), methane and nitrous oxide – all broke records in 2022.
Such levels of heat-trapping gases will mean more temperature rises,
“Despite decades of warnings from the scientific community, thousands of pages of reports and dozens of climate conferences, we are still heading in the wrong direction,” said WMO chief Petteri Taalas.
The bulletin comes ahead of the COP28 UN climate summit, which will take place in Dubai from Nov 30 to Dec 12.
In the 2015 Paris Agreement, countries agreed to cap global warming at “well below” 2 deg C above average levels measured between 1850 and 1900 – and 1.5 deg C if possible.
The global mean temperature in 2022 was 1.15 deg C above the 1850 to 1900 average.
“The current level of greenhouse gas concentrations puts us on the pathway of an increase in temperatures well above the Paris Agreement targets by the end of this century,” said Professor Taalas.
“This will be accompanied by more extreme weather, including intense heat and rainfall, ice melt, sea level rise, and ocean heat and acidification.
“The socioeconomic and environmental costs will soar. We must reduce the consumption of fossil fuels as a matter of urgency.”
‘No magic wand’
In 2022, CO2 concentrations were at 418 parts per million; methane at 1,923 parts per billion; and nitrous oxide at 336 parts per billion. These values constitute, respectively, 150 per cent, 264 per cent and 124 per cent of pre-industrial (before 1750) levels.
Of the three major greenhouse gases, CO2 accounts for about 64 per cent
Global averaged concentrations of CO2 in 2022 were, for the first time, 50 per cent above those of the pre-industrial era, “primarily because of emissions from the combustion of fossil fuels and cement production”, said the WMO.
CO2 atmospheric concentrations “continued to grow in 2023”.
“Given the long life of CO2, the temperature level already observed will persist for several decades even if emissions are rapidly reduced to net zero,” the WMO warned, with Prof Taalas adding: “There is no magic wand to remove the excess CO2 from the atmosphere.”
Atmospheric methane is the second-largest contributor to climate change, accounting for around 16 per cent of the warming effect.
Methane remains in the atmosphere for only about 10 years, but has a much more powerful warming impact than CO2.
The methane increase in 2022 was slightly lower than the 2021 increase, but considerably higher than the average annual growth rate over the last decade.
For nitrous oxide – accounting for around 7 per cent of the warming effect – the increase in 2022 “was higher than that observed any time before in our modern time record”, the WMO said.
Tipping points
Although the scientific community has a broad understanding of climate change and its implications, there are still some uncertainties about the carbon cycle – and fluxes in the ocean, the land biosphere and permafrost areas.
The bulletin called for greater information on certain topics.
These included feedback loops in the climate system – for example, increased carbon emissions from soils or decreased carbon uptake by oceans due to climate change.
The WMO is also concerned about so-called tipping points, where a certain level of change leads to a self-accelerating and potentially irreversible cascade of changes.
The organisation said more information is also needed on non-CO2 greenhouse gases. AFP

