Reacción a "Reactions to the detection of record methane concentrations in the atmosphere"

This is the largest measured annual increase since 2011 and is highly significant considering that the past two years have seen an economic (and in principle anthropogenic emissions) slowdown caused by the response to the coronavirus pandemic. Despite this slowdown, methane levels continue to rise relentlessly.

CH₄ remains in the atmosphere for a shorter period of time than CO₂ (about 10-12 years) and is considered a short-term climate forcer. Although its emissions are lower than CO₂, its global warming potential (ability to trap heat in the atmosphere) is 28-34 times higher. The observed annual increase in methane concentrations is therefore a very negative impact on the fight against climate change.

At this stage, it is very difficult to give a precise explanation as to why this peak is occurring. Specific studies will be needed to analyse different factors affecting global methane concentrations in the atmosphere, such as changes in the different emission sources (biological and anthropogenic) and potential variations in the chemical processes responsible for removing methane from the atmosphere. The causes are likely to be a combination of all these elements.

As an illustration, the European Space Agency (ESA) recently published a news item suggesting that during 2020 and in a large oil and natural gas production area in the USA, CH₄ emissions had increased compared to the previous year. One possible explanation for this could be that, as a result of lower demand for natural gas in the industrial sector due to covid-19, natural gas is burnt, leading to higher methane emissions in this area. I repeat that this example is only illustrative and does not pretend to explain the causes of the observed peak, but there are surely multiple reasons that will have to be analysed during the following months.