I found an interesting article in New Scientist.
A mysterious rise in methane levels is sparking global warming fears
Last year in Corona, the growth of methane levels was twice as high as in 2007. We don't know why, but climate change may have led to warmer temperatures, which has increased microbial activity in the wetlands, causing more methane to be produced. Wetlands may not sound like much, but the water used to grow rice is also a wetland. Paddy fields in Asia, like deforestation in Europe, have been a factor in climate change since before the industrial revolution. Half of today's methane emissions are fossil fuel-related, but the other half comes from agriculture and land use. The current methane spike is thought to have been emitted from the latter biological activity.
Methane gas is not as much of a long-term contributor to climate change as carbon dioxide, but its greenhouse effect is said to be about 30 times that of carbon dioxide. The article says that of the three major greenhouse gases, methane is the easiest to tackle. Carbon dioxide emissions are directly linked to human economic activity, so it is always a debate between development and climate change that drives the reduction of carbon dioxide emissions. Nitrous oxide, another greenhouse gas, comes from chemical fertilisers, which I wrote about in yesterday's blog. This, too, is always weighed up against the food issue as a trade-off for efficient farming.
Compared to the other two gases, methane gas is less likely to lead to trade-offs with development issues. Methane gas is also at the heart of biogas, produced by animals and can be captured and used effectively as biogas, so keeping methane gas out of the air is a way of ensuring energy security and therefore rising development.
The United Nations Environment Programme estimates that by 2040 it is possible to reduce global warming by about 0.3 degrees Celsius if we reduce methane emissions by 45% by 2030. Another study suggests that we could reduce warming by 0.25 degrees by the end of the century if we reduce easy methane emissions.
In addition, with cultivated methern gases, such as the one su-re.co are installing, the residues can be used effectively as organic fertilisers, thus reducing the use of chemical fertilisers. So, at the same time, biogas digesters can reduce nitrous oxide emissions.