Greenhouse gases (GHGs) reached a new record high in 2022, with "no end in sight to the rising trend", the World Meteorological Organisation (WMO) said today.
Global average concentrations of the three key GHGs — CO2, methane and nitrous oxide — increased in 2022 and continue to rise in 2023, WMO data show. The rate of growth in CO2 concentrations was "slightly lower" than the previous year and the average for the decade, although this is most likely because of increased absorption of CO2 by the earth and ocean, after a rare "triple-dip" La Nina event. This year's El Nino event "may therefore have consequences" for GHG concentrations, the WMO said. The El Nino weather pattern typically leads to higher temperatures, while La Nina has the opposite effect.
The rate of growth for methane concentrations over 2021-22 was slightly lower than the previous year, but "considerably higher" than the average annual growth rate over the past decade. And the year on year increase in levels of nitrous oxide from 2021-22 was the highest on record, the WMO said. The record levels of GHGs mean further global temperature increases, it added.
"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... We must reduce the consumption of fossil fuels as a matter of urgency", WMO secretary-general Petteri Taalas said.
The Paris agreement sets out a goal of limiting global warming to "well below" 2°C above pre-industrial averages, and preferably to 1.5°C.
The warming effect on global climate from GHGs, known as radiative forcing, increased by 49pc from 1990 to 2022. CO2 accounted for the majority of the increase, at around 78pc, WMO said. "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", Taalas said.
The WMO published its annual GHG bulletin to inform the UN Cop 28 climate summit, due to begin on 30 November in Dubai, UAE.
