Washington, Apr 8 (EFE).- Scientists have observed a record annual increase in atmospheric levels of planet-warming methane in 2021, a new study published Thursday by an American scientific and regulatory agency showed.
The study by the United States National Oceanic and Atmospheric Administration has found that the annual increase in atmospheric methane during 2021 was 17 parts per billion (ppb), the largest since measurements began in 1983.
Methane, a heat-trapping greenhouse gas, is the second biggest contributor to human-caused global warming after carbon dioxide.
The increase in atmospheric methane levels in 2020 was 15.3 ppb.
It averaged 1,895.7 ppb in 2021, or around 162 percent greater than pre-industrial levels.
From NOAA’s observations, scientists estimate global methane emissions in 2021 are 15 percent higher than between 1984 and 2006.
Methane in the atmosphere is generated by many different sources, such as fossil fuel production, transport, and use, from the decay of organic matter in wetlands, and as a byproduct of digestion by ruminant animals such as cows.
The NOAA study said determining which specific sources were responsible for variations in annual increases of methane was complex.
But scientists estimate that fossil fuel production and use contribute roughly 30 percent of the total methane emissions.
These industrial sources of methane are relatively simple to pinpoint and control using current technology.
The study found that carbon dioxide levels also increased at historically high rates.
The global surface average for carbon dioxide during 2021 was 414.7 parts per million (ppm), which is an increase of 2.66 ppm over the 2020 average.
“This marks the 10th consecutive year that carbon dioxide increased by more than 2 parts per million, which represents the fastest sustained rate of increase in the 63 years since monitoring began,” said the study.
“Our data show that global emissions continue to move in the wrong direction at a rapid pace,” said NOAA administrator Rick Spinrad
“The evidence is consistent, alarming and undeniable. We need to build a Climate Ready Nation to adapt for what’s already here and prepare for what’s to come,” said Spinrad.
He said the world could no longer afford to delay urgent and effective action needed to address the cause of the problem — greenhouse gas pollution.
Agency experts warned of the cumulative effect of carbon dioxide emissions.
Pieter Tans, senior scientist with the Global Monitoring Laboratory, said about 40 percent of the Ford Model T emissions from 1911 were still in the air today.
“We are halfway to doubling the abundance of carbon dioxide that was in the atmosphere at the start of the Industrial Revolution.”
The NOAA study said the atmospheric residence time of methane is approximately nine years, whereas carbon dioxide “emitted today will continue to warm the planet for thousands of years.”