“Fossil fuels may not be the primary driver of the increase in atmospheric methane, but there is still a great potential for the fossil fuel industry to help mitigate climate change by cutting its emissions. Carbon isotope analysis will help tell us if their efforts are working.” Xin Lan. NOAA’s Global Monitoring Laboratory
The methane bomb may become the dreaded reality that NOAA scientists have warned about for decades. The agency released new findings on a jaw-dropping surge of methane greenhouse gas in the atmosphere that does not make the headlines that a comparable wave of CO2 would attract. Though fossil fuel use has been the primary driver of methane pre-2007, new research from the Institute of Arctic and Alpine Research at the University of Colorado found that microbial sources feed the surge in the deadly greenhouse gas. Methane from fossil fuels consists of thirty percent of methane emissions, the rest from a myriad of sources many of which we can do nothing to stop.
For the second year in a row, NOAA scientists observed a record annual increase in atmospheric levels of methane, a powerful, heat-trapping greenhouse gas that’s the second biggest contributor to human-caused global warming after carbon dioxide.
NOAA’s preliminary analysis showed the annual increase in atmospheric methane during 2021 was 17 parts per billion (ppb), the largest annual increase recorded since systematic measurements began in 1983. The increase during 2020 was 15.3 ppb. Atmospheric methane levels averaged 1,895.7 ppb during 2021, or around 162% greater than pre-industrial levels. From NOAA’s observations, scientists estimate global methane emissions in 2021 are 15% higher than the 1984-2006 period.
Meanwhile, levels of carbon dioxide also continue to increase 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.
NOAA Research News reported on the microbial link to soaring methane levels. The findings were published in the journal Global Biogeochemical Cycles.
Lan said the data pointed to microbial sources, such as natural wetlands, shallow lakes and rivers, and human-managed sources like livestock, landfills, rice paddies, and wastewater treatment.
“Our analysis indicates that methane emissions from fossil fuels are unlikely to be the dominant driver of the post-2006 increase,” said Lan. “The long-term change can’t be explained by a reduction in the rate at which the atmosphere degrades methane either.”
Methane, which is far less abundant but 28 times more potent than CO2 at trapping heat over a 100-year time frame, is emitted to the atmosphere from three major source categories, fossil fuels, microbials and biomass/biofuel burning. If microbial methane emissions from wetlands are increasing due to climate change, then that would constitute an extremely concerning climate feedback cycle that could amplify warming, Lan said.
NOAA continues on the state of human CO2 emissions in the atmosphere being the biggest threat to a livable climate.
While there’s been scientific debate on the cause of the ongoing surge in methane levels, carbon dioxide pollution has always been the primary driver of human-caused climate change. An estimated 36 billion tons of carbon dioxide were emitted into the atmosphere last year by human activity; roughly 640 million tons of methane were emitted during the same period. The atmospheric residence time of methane is approximately nine years, whereas some of the carbon dioxide emitted today will continue to warm the planet for thousands of years.
Atmospheric levels of carbon dioxide are now comparable to where they were during the mid-Pliocene epochoffsite link, around 4.3 million years ago. During that period, sea level was about 75 feet higher than today, the average temperature was 7 degrees Fahrenheit higher than in pre-industrial times, and studies indicateoffsite link large forests occupied areas of the Arctic that are now tundra.
“The effect of carbon dioxide emissions is cumulative,” said Pieter Tans, senior scientist with the Global Monitoring Laboratory. “About 40% of the Ford Model T emissions from 1911 are still in the air today. We’re halfway to doubling the abundance of carbon dioxide that was in the atmosphere at the start of the Industrial Revolution.”
NOAA notes that controlling methane emissions today is technically possible. If we need any more reasons to act it would be an increase in surface ozone. Slather on the sun lotion if you need to go outside for any reason. I’ll leave it to you to decide if sapiens decide to act or not.
