NEW DELHI: Carbon dioxide (CO2) concentration in the atmosphere is rising faster than ever in human history, says a World Meteorological Organisation (WMO) report.
A new report by the WMO shows that greenhouse gas levels surged to a new record in 2023. It states that the accumulation of CO2 in the atmosphere is faster than ever, rising by more than 11 per cent in just two decades.
The 2023 increase of CO2 in the atmosphere was higher than that of 2022, although lower than that of the three years prior. The annual increase of 2.3 parts per million (ppm) marked the 12th consecutive year with an increase greater than 2 ppm.
According to the WMO’s annual Greenhouse Gas Bulletin, one of the main reasons behind the high level of emissions is large-scale forest and vegetation fires in 2023, which possibly reduced the absorption capacity of CO2.
This issue was further worsened by human activities, such as fossil fuel burning for energy and industrial processes, which also drive up CO2 emissions.
The WMO’s annual Greenhouse Gas Bulletin is a flagship publication that tracks the concentration rather than the emission of greenhouse gases (GHGs) in the atmosphere.
The globally averaged surface concentration of CO2 reached 420.0 ppm, methane 1,934 parts per billion, and nitrous oxide 336.9 parts per billion (ppb) in 2023. These values are 151 per cent, 265 per cent, and 125 per cent of pre-industrial (before 1750) levels, it said. These figures are calculated based on long-term observations within the Global Atmosphere Watch network of monitoring stations.
The last time the Earth experienced a comparable concentration of CO2 was 3 to 5 million years ago when the temperature was 2 to 3 degrees Celsius warmer, and the sea level was 10 to 20 meters higher than it is now.
From 1990 to 2023, radiative forcing (the warming effect on our climate) by long-lived greenhouse gases increased by 51.5 per cent, with CO2 accounting for about 81 per cent of this increase.
The 20th issue of publications released to inform the UN Climate Change Conference, COP 29, states that the CO2 level has increased by 11.4 per cent (42.9 ppm) above the level of 377.1 ppm recorded in 2004 by the WMO’s Global Atmosphere Watch network of monitoring stations.
“Another year and another record,” said WMO Secretary-General Celeste Saulo. “This should set alarm bells ringing among decision-makers. We are clearly off track to meet the Paris Agreement goal of limiting global warming to well below 2 degrees Celsius and aiming for 1.5 degrees Celsius above pre-industrial levels. These are more than just statistics,” Celeste further stated.
Analysis of data shows that just under half of CO2 emissions remain in the atmosphere. Just over one quarter are absorbed by the ocean, and just under 30 per cent by land ecosystems - although there is considerable year-to-year variability in this due to naturally occurring phenomena like El Niño and La Niña.
During El Niño years, greenhouse gas levels tend to rise because drier vegetation and forest fires reduce the efficiency of land carbon sinks.
“The Bulletin warns that we face a potential vicious cycle,” said WMO Deputy Secretary-General Ko Barrett.
“Wildfires could release more carbon emissions into the atmosphere, while the warmer ocean might absorb less CO2,” Barrett added.