Greenhouse gas (GHG) levels hit a record high in 2023, with annual mean levels of carbon dioxide (CO2) rising by 2.3 parts per million (PPM) between 2022 and 2023, according to a report by World Meteorological Organization (WMO) released on Monday. The annual mean carbon dioxide rose by over 2 PPM for the twelfth consecutive year. CO2 has risen by 11.4 per cent in just two decades.
Last year was also the warmest on record, exceeding 2016 levels. It was 1.48°C warmer than the average of the 1850-1900 pre-industrial level.
This comes ahead of the 29th Conference of the Parties (COP29) to the United Nations Framework Convention on Climate Change (UNFCCC) to be held next month in Baku, Azerbaijan. UN secretary general Antonio Guterres along with others have repeatedly warned countries about the human cost of ignoring the existential crisis.
Advertisement
WMO report mentioned that forest fires and El Niño effect contributed to warming weather and reduction in rainfall, especially in South Africa. This led to drier conditions and an increase in GHG concentration in the second half of 2023.
Only a portion of carbon dioxide is absorbed by the ocean, less than 30 per cent of it is retained on the land and the rest remains in the atmosphere, the analysis showed. The WMO report observed that even if GHG emissions reduce rapidly to meet net zero targets, high temperatures will persist for several decades due to extremely long life of carbon dioxide in the atmosphere.
Advertisement
India’s contribution to the global carbon dioxide stood at 8 per cent in 2023, with the country’s GHG emissions surging to 6.1 per cent in that year, according to United Nations Environment Programme (UNEP) Emissions Gap Report 2024 released last week. Historically, India’s contribution has only been 3 per cent.
Stuck in a Vicious Circle
“The bulletin warns that we face a potential vicious cycle. Natural climate variability plays a big role in the carbon cycle. But in the near future, climate change itself could cause ecosystems to become larger sources of greenhouse gases. Wildfires could release more carbon emissions into the atmosphere, whilst the warmer ocean might absorb less carbon dioxide,” said WMO deputy secretary-general Ko Barrett.
“Consequently, more carbon dioxide could stay in the atmosphere to accelerate global warming. These climate feedbacks are critical concerns to human society,” Barrett added.
The report highlighted that climate concerns extend beyond carbon dioxide. Methane present in the earth’s atmosphere witnessed the largest three-year increase between 2020 and 2022 from natural wetlands in response to warmer temperatures and particularly wetter land conditions during the 2020-2022 La Nina conditions.
The globally-averaged surface concentration of methane reached 1 934 parts per billion (ppb) in 2023, 265 per cent of pre-industrial (before 1750) levels, the report said.
Current Climate Plans are Not Enough
Meanwhile, the UNFCCC said in its annual assessment on Monday that the nationally determined contributions (NDCs) can cut global emissions by 2.6 per cent from 2019 to 2030. However, even if NDCs are implemented completely until 2030, global mean temperatures could still rise in the range of 2.1–2.8°C by 2100.
Advertisement
As part of their Paris obligations, countries must deliver new and stronger NDCs before February next year.
“Current national climate plans fall miles short of what’s needed to stop global heating from crippling every economy and wrecking billions of lives and livelihoods across every country,” Simon Stiell, UNFCCC secretary general said. “The last generation of NDCs set the signal for unstoppable change,” added Stiell. “New NDCs next year must outline a clear path to make it happen.”