Scientists have expressed concern at the surging concentration of methane in the atmosphere, as its levels have escalated dramatically in recent years.
This was carried out in two new studies published on Dec. 12 in Earth System Science Data and Environmental Research Letters, where it was noted that methane emissions have jumped alarmingly as if in a globally worst-case scenario.
The papers were co-authored by Rob Jackson, chair of Stanford's Earth System Science Department and head of the Global Carbon Project.
Noting that methane concentrations were 0.5 parts per billion per year in the early 2000s, in the past two years, the Environmental Research Letters said they rose to 12.5 parts per billion in 2014 and 9.9 parts per billion in 2015.
The studies assert that a major opportunity in avoiding climate change's worst impact is mounting an effective check on the surging methane emissions — with the agriculture sector as its main emitter. Cattle as a component of the farming sector emit most methane through bodily functions and manure.
Grave Danger From Rising Methane Levels
The danger about methane is that if left unchecked, the rising levels could drive up temperatures by 6 degrees Fahrenheit (4 degrees Celsius) causing a huge sea level rise and bad weather conditions.
The researchers warn that efforts to tackle climate change would flounder if methane level is not brought under control.
It must be noted that most mitigation efforts have been focused on containing carbon dioxide emissions with calls to shun fossil fuels. This is despite methane's warming potential 28 times more than carbon dioxide on a 100-year scale.
"CO2 is still the dominant target for mitigation, for good reason. But we run the risk if we lose sight of methane of offsetting the gains we might make in bringing down levels of carbon dioxide," said Jackson.
Significantly, the study coincides with the move made by some congressional members in reversing methane-limiting standards for the natural gas industry.
There is a consensus that methane content must be brought under control to solve the climate change riddle rather smoothly.
Difficult Gas To Track
Jackson reminds that methane is a difficult gas to track as the sources are varied — ranging from natural sources like marshes and other wetlands. However, the bulk of methane emission is from human activities that include cattle operations and flooded soils where microbes produce the gas. One-third of methane comes from fossil fuel exploration where it is leaked from the oil wells during drilling.
Jackson said the lesson is that the kind of attention fossil fuel industry has been receiving in recent years must go to the agricultural emissions while examining the rise of methane from food production.
"Why this change happened is still not well understood," said Marielle Saunois, lead author of the paper, who is an assistant professor at Université de Versailles Saint Quentin in France.
"For the last two years especially, the growth rate has been faster than for the years before. It's really intriguing," Saunois added.
Nevertheless, Saunois and Jackson console that all is not lost and methane emission from cattle can be still be curbed by feeding cows a diet supplemented with linseed oil.
