Methane emissions are increasing. And that’s not good for the climate. The concentration of this hydrocarbon in the Earth’s atmosphere is now 2.5 times greater than it was during the pre-industrial era! This is the observation made by a team of scientists from the Future Earth research program .
Twenty-five times warmer than CO 2
Methane is a greenhouse gas which, according to NASA, is the second responsible for climate change after CO 2 . However, it is twenty-five times warmer than the latter. It has always more or less spread in the atmosphere. 30% of emissions come from wetlands such as lakes or rice fields; 30% of oil, natural gas and coal extraction; 20% of agriculture, more particularly livestock. For the remaining 20%, the sources are diverse: forest fires, combustion of biomass – wood therefore -, dams, termites and melting permafrost.
It is this last source that worries researchers. A large amount of methane is believed to be in Antarctica , trapped in permafrost, permanently frozen soils, and in the seabed. Scientists recently discovered the first continuous leak of methane into the sea floor. The thaw of the permafrost, which arrives seventy years earlier than expected, and the warming of the oceans pave the way for a worrying situation, in which mass methane emissions would be inevitable, scientists alarm.
Manon BERNARD.
