Phys.org September 24, 2024
The causes for the rapid rise of atmospheric methane concentrations over the past decade have been unclear. An international team of researchers (USA – Harvard University, Jet Propulsion Laboratory, UK) found that emissions from the wet tropics drove the 2010–2019 increase and the subsequent 2020–2022 surge, while emissions from northern mid-latitudes decreased. The 2020–2022 surge was principally contributed by emissions in Equatorial Asia and Africa. Wetlands were the major drivers of the 2020–2022 emission increases in Africa and Equatorial Asia because of tropical inundation associated with La Niña conditions, consistent with trends in the GRACE terrestrial water storage data. In contrast, emissions from major anthropogenic emitters such as the United States, Russia, and China were relatively flat over 2010–2022. Concentrations of tropospheric OH (the main methane sink) showed no long-term trend over 2010–2022 but a decreased over 2020–2022 that contributed to the methane surge… read more. Open Access TECHNICAL ARTICLE
(A and B) Regional trends of methane emissions informed by GOSAT for 2010–2022. Credit: PNAS, September 24, 2024, 121 (40) e2402730121