The concentration of methane, a potent greenhouse gas, rose to record levels in the atmosphere last year, as did CO2 and nitrogen oxide, the UN announced on Wednesday.
In a statement, the World Meteorological Organization (WMO) explains that the reason for this exceptional increase in the concentration of methane, which has a much more potent but less lasting effect than CO2, “is unclear, but appears to be the result of biological and man-made processes.”
These figures “represent the enormous challenge – and the essential need – for urgent action to reduce greenhouse gas emissions and prevent global temperatures from rising further,” said WMO Secretary-General Petteri Taalas.
On the same day, the UN Climate Change Office warned that the latest international commitments are “far away” from meeting the Paris Agreement target of limiting global warming to +1.5°C.
“We’re going in the wrong direction”Taalas emphasized.
In 2020 and 2021, the concentration of methane – the second largest contributor to global warming – increased by 15 and 18 parts per billion (ppb), respectively. It is difficult to determine the source of emissions because the sources and ‘sinks’ that absorb the gas can be confused with each other, the WMO explains.
“There are cost-effective strategies to tackle methane emissions, especially in the fossil fuel sector, and we need to put them into practice without delay,” Petteri insisted.
There has been a lot of discussion about methane lately, especially after the sabotage of the Nord Stream pipeline and the so-called cattle flatulence tax being proposed in New Zealand.
On Tuesday, NASA (the US space agency) revealed that it had detected dozens of methane “super emitters” from space, places normally associated with waste disposal or agriculture.
As for the continued increase in atmospheric methane concentrations since 2007, scientists aren’t sure, but believe that it “comes largely from biogenic sources, such as swamps or rice paddies.”
It is too early to say whether the increases in 2020 and last year are due to the faster decomposition of organic matter in the water under the influence of increased heat, or to episodes of the La Niña phenomenon, which created favorable conditions for methane emissions as precipitation in tropical areas increases. Taalas emphasizes, however, that the enemy to be defeated is primarily carbon dioxide.
“The absolute priority is to drastically and urgently reduce carbon dioxide emissions, which are the main cause of climate change and associated extreme weather events”warned the secretary general of the WMO, adding that these emissions will affect the climate for thousands of years with the melting of ice at the poles, warming of the oceans and rising sea levels.
In 2021, the concentration of carbon dioxide in the atmosphere reached 415.7 parts per million (ppm); methane, 1,908 parts per billion (ppb); and nitrogen oxide, 334.5 ppb, an increase of 149%, 262% and 124% respectively compared to the pre-industrial era.
Global CO2 emissions have risen again since the end of lockdowns due to the Covid-19 pandemic in 2020.
Between 2011 and 2020, approximately 48% of total CO2 emissions related to human activities accumulate in the atmosphere; 26%, in the oceans; and 29%, in the terrestrial biosphere.
“There is concern that terrestrial ecosystems and oceans are less effective in their roles as ‘sinks,’ which would reduce their ability to absorb carbon dioxide and prevent a sharper rise in temperature,” the WMO said, adding that in certain regions of the world , CO2 sinks become sources of the gas.
Source: DN
