Experts might have found a way to explain some of the recent recorded growth in methane levels in our atmosphere.
A team of researchers from the UK conducted studies that prove a significant boost in emissions originating from the wetlands of South Sudan. The scientists used data satellite data that indicate the mentioned region’s emissions raise global CH4 levels.
Professor Paul Palmer said: “There’s not much ground-monitoring in this region that can prove or disprove our results, but the data we have fits together beautifully. We have independent lines of evidence to show the Sudd wetlands expanded in size, and you can even see it in aerial imagery – they became greener.”
Methane, much like carbon dioxide, is a greenhouse gas that has become more and more concentrated in the atmosphere during the past years. However, emission levels haven’t been rising steadily. During the early 2000s, the levels stabilized for a while, but the concentration raised drastically in 2007 and 2014.
Currently, methane stands at just over 1,860 parts per billion by volume.
Experts have been debating the likely human activity-related sources, but there is also a natural component that needs to be taken into consideration.
The team of researchers used the Japanese GOSAT spacecraft to observe the wetlands of Africa, discovering significant rises in methane emissions in the 2011-2014 timeframe. Soil microbes in the wetlands are known to produce methane, so the team studied more satellite data sets. They discovered that the soil in the area had become wetter, with more water being held in the ground, which could have led to larger amounts of microbes in the soil.
Dr. Lunt told BBC: “It’s a huge area, so it’s not surprising that it’s pumping out a lot of methane. To give context – the Sudd is 40,000 sq km: two times the size of Wales. And being that big, we expect to see the emissions from space.”
The findings were published on December 11, 2019, in the journal Atmospheric Chemistry and Physics.