A new study reveals that methane may not be warming the Earth as much as previously thought. Read to know more.
The reality of methane as a global warmer.
Methane, a greenhouse gas has dual attributes. It is behind heating the Earth’s atmosphere by 28 times more than carbon dioxide. On the other hand, its ability to absorb solar radiation can alter cloud patterns. This leads to clouds casting a shadow on its warming effects. In a new study published in Nature Geoscience, researchers revealed that by adding more thermal energy to the atmosphere, the gas’ ability to absorb solar absorption can set off a chain of events. This can reduce the greenhouse gas warming effect by 30 percent.
“These are really interesting and important results. Nonetheless, methane remains a key gas that we need to target in emissions reductions,” stated Rachel Byrom. Byrom is a climate scientist at the Center for International Climate Research in Oslo (CICERO), who is not involved in the study. Currently, the largest sources of gas from anthropogenic methods include rice farming, livestock, fossil fuel usage, biomass burning, and landfills. Researchers fear that as warming triggers the thawing of permafrost in the Arctic, this may cause microbes in the soil to consume plant material and release methane. Hence leading to higher emissions of the greenhouse gas.
More on the climate change aspect
Greenhouse gases such as methane are known for exerting their strong effects by absorbing longwave infrared (IR) radiation emitted from Earth waves. The earth emits this radiation when struck by shortwave IR from the sun. New studies reveal that greenhouse gases absorb some of the sun’s radiation hence contributing more. When methane absorbs the shortwave radiation from the sun, it warms the air in the middle and upper troposphere. Hence, less radiation can penetrate the lower regions, leading to the colling of the lower troposphere and more cloud generation.
With this, “you expect a warming of the climate system. But these cloud adjustments overwhelm the heating due to absorption, leading to a cooling effect,” explained Robert Allen. Allen is a climate scientist at the University of California, Riverside. Additionally, due to this, methane is also believed to help increase global precipitation. Further work in the field will help in better clarifying the effects of greenhouse gases.