How do cows and sheep contribute to climate change?

How do cows and sheep contribute to climate change?

Subject: Environment

Section: Climate change

Context: Microsoft co-founder Bill Gates has invested in an Australian climate technology start-up that aims to curtail the methane emissions of cow burps, according to a report in the BBC.

More on the News:

• The start-up, Rumin8, has received funding worth $12 million from Breakthrough Energy Ventures, which Gates created in 2015.
• 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.

How do cows and other animals produce methane?

• Ruminant species are hooved grazing or browsing herbivores that chew cud. Ruminants such as cows, sheep, goats, and buffaloes 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. Ruminant animals such as cows and sheep release this methane mainly through burping.
• 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.

And 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 United Nations Environment Programme.
• 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.
• Several studies have shown that in recent years, the amount of methane in the atmosphere has dramatically shot up. In 2022, the US National Oceanic and Atmospheric Administration (NOAA) said that the atmospheric levels of methane jumped 17 parts per billion in 2021, beating the previous record set in 2020.
• While carbon dioxide remains in the atmosphere for much longer than methane, methane is roughly 25 times more powerful at trapping heat in the atmosphere, and has an important short-term influence on the rate of climate change.

How are researchers trying to mitigate methane emissions?

• Scientists have been working on it for quite some time now, as they are looking 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.
• New Zealand is also one of the first nations to come up with policy-related solutions to this problem.