From UPSC perspective, the following things are important :
Prelims level : Methane Pollution
Mains level : Not Much
Bill Gates has invested in a climate technology start-up that aims to curtail the methane emissions of cow burps.
What is the news?
- The startup Rumin8 is developing a variety of dietary supplements to feed to cows in a bid to reduce the amount of methane they emit into the atmosphere.
- The supplement includes red seaweed, which is believed to drastically cut methane output in cows.
What is Methane?
- Methane is a greenhouse gas, which is also a component of natural gas.
- There are various sources of methane including human and natural sources.
- The anthropogenic sources are responsible for 60 per cent of global methane emissions.
- It includes landfills, oil and natural gas systems, agricultural activities, coal mining, wastewater treatment, and certain industrial processes.
- The oil and gas sectors are among the largest contributors to human sources of methane.
- These emissions come primarily from the burning of fossil fuels, decomposition in landfills and the agriculture sector.
How do cows and other animals produce methane?
- Ruminant animals such as cows, sheep, goats, and buffaloes release this methane mainly through burping.
- They have a special type of digestive system that allows them to break down and digest food that non-ruminant species would be unable to digest.
- Stomachs of ruminant animals have four compartments, one of which, the rumen, helps them to store partially digested food and let it ferment.
- This partially digested and fermented food is regurgitated by the animals who chew through it again and finish the digestive process.
- However, as grass and other vegetation ferments in the rumen, it generates methane, a potent greenhouse gas.
How much do these ruminants contribute to emissions?
- Given the very large numbers of cattle and sheep on farms in dairy-producing countries, these emissions add up to a significant volume.
- It is estimated that the ruminant digestive system is responsible for 27 per cent of all methane emissions from human activity.
Why is methane such a big problem?
- Methane is one of the main drivers of climate change, responsible for 30 per cent of the warming since preindustrial times, second only to carbon dioxide.
- Over a 20-year period, methane is 80 times more potent at warming than carbon dioxide, according to a report by the UNEP.
- It’s also the primary contributor to the formation of ground-level ozone, a colourless and highly irritating gas that forms just above the Earth’s surface.
- According to a 2022 report, exposure to ground-level ozone could be contributing to 1 million premature deaths every year.
- Several studies have shown that in recent years, the amount of methane in the atmosphere has dramatically shot up.
Mitigating methane emissions
- Scientists have been working on to make these animals more sustainable and less gassy.
- A 2021 study, published in the journal PLUS ONE, found that adding seaweed to cow feed can reduce methane formation in their guts by more than 80 per cent.
- Apart from this, researchers are also trying to find gene-modifying techniques to curtail methane emissions in these animals.
- Last year, scientists in New Zealand announced they had started the world’s first genetic programme to address the challenge of climate change by breeding sheep that emit lower amounts of methane.
Global collaboration against methane pollution
Ans. Global Methane Initiative (GMI)
- GMI is a voluntary Government and an informal international partnership having members from 45 countries including the United States and Canada.
- India last year co-chaired along with Canada the GMI leadership meet held virtually.
- The forum has been created to achieve global reduction in anthropogenic methane emission through partnership among developed and developing countries having economies in transition.
- The forum was created in 2004 and India is one of the members since its inception and has taken up Vice-Chairmanship for the first time in the Steering Leadership along with USA.
Back2Basics: CO2 Equivalents
- Each greenhouse gas (GHG) has a different global warming potential (GWP) and persists for a different length of time in the atmosphere.
- The three main greenhouse gases (along with water vapour) and their 100-year global warming potential (GWP) compared to carbon dioxide are:
1 x – carbon dioxide (CO2)
25 x – methane (CH4) – I.e. Releasing 1 kg of CH4into the atmosphere is about equivalent to releasing 25 kg of CO2
298 x – nitrous oxide (N2O)
- Water vapour is not considered to be a cause of man-made global warming because it does not persist in the atmosphere for more than a few days.
- There are other greenhouse gases which have far greater global warming potential (GWP) but are much less prevalent. These are sulphur hexafluoride (SF6), hydrofluorocarbons (HFCs), and perfluorocarbons (PFCs).
- There are a wide variety of uses for SF6, HFCs, and PFCs but they have been most commonly used as refrigerants and for fire suppression.
- Many of these compounds also have a depleting effect on ozone in the upper atmosphere.