Methane is one of the most dangerous greenhouse gases… and, is part of an exponential negative feedback loop:
Methane in the atmosphere causes the climate to warm
A warmer climate causes permafrost to melt…
Releasing more methane and CO2…
Making the climate warmer…
Melting more permafrost…
Releasing more methane and CO2…
Melting, more permafrost, etc., etc., etc
“And is there a tipping point that could trigger rapid thaw? Scientists estimate that there is about twice as much carbon stored in permafrost as circulating in the atmosphere. … Once the organic matter within permafrost decomposes and releases CO2 and methane, there is no getting it back,” said Dr Christina Schädel.
In a report for Stanford University, Josie Garthwaite states:
lobal emissions of methane have reached the highest levels on record. Increases are being driven primarily by growth of emissions from coal mining, oil and natural gas production, cattle and sheep ranching, and landfills.
Between 2000 and 2017, levels of the potent greenhouse gas barreled up toward pathways that climate models suggest will lead to 3-4 degrees Celsius of warming before the end of this century. This is a dangerous temperature threshold at which scientists warn that natural disasters, including wildfires, droughts and floods, and social disruptions such as famines and mass migrations become almost commonplace. The findings are outlined in two papers published July 14 in Earth System Science Data and Environmental Research Letters by researchers with the Global Carbon Project, an initiative led by Stanford University scientist Rob Jackson.
Globally, fossil fuel sources and cows are twin engines powering methane’s upward climb. “Emissions from cattle and other ruminants are almost as large as those from the fossil fuel industry for methane,” Jackson said. “People joke about burping cows without realizing how big the source really is.”
Throughout the study period, agriculture accounted for roughly two-thirds of all methane emissions related to human activities; fossil fuels contributed most of the remaining third. However, those two sources have contributed in roughly equal measure to the increases seen since the early 2000s.
Methane emissions from agriculture rose to 227 million tons of methane in 2017, up nearly 11 percent from the 2000–2006 average. Methane from fossil fuel production and use reached 108 million tons in 2017, up nearly 15 percent from the earlier period.
Amid the coronavirus pandemic, carbon emissions plummeted as manufacturing and transportation ground to a halt. “There’s no chance that methane emissions dropped as much as carbon dioxide emissions because of the virus,” Jackson said. “We’re still heating our homes and buildings, and agriculture keeps growing.”