Methane release from carbonate rock formations in the Siberian permafrost area during and after the 2020 heat wave

Abstract

Anthropogenic global warming may be accelerated by a positive feedback from the mobilization of methane from thawing Arctic permafrost. There are large uncertainties about the size of carbon stocks and the magnitude of possible methane emissions. Methane cannot only be produced from the microbial decay of organic matter within the thawing permafrost soils (microbial methane) but can also come from natural gas (thermogenic methane) trapped under or within the permafrost layer and released when it thaws. In the Taymyr Peninsula and surroundings in North Siberia, the area of the worldwide largest positive surface temperature anomaly for 2020, atmospheric methane concentrations have increased considerably during and after the 2020 heat wave. Two elongated areas of increased atmospheric methane concentration that appeared during summer coincide with two stripes of Paleozoic carbonates exposed at the southern and northern borders of the Yenisey-Khatanga Basin, a hydrocarbon-bearing sedimentary basin between the Siberian Craton to the south and the Taymyr Fold Belt to the north. Over the carbonates, soils are thin to nonexistent and wetlands are scarce. The maxima are thus unlikely to be caused by microbial methane from soils or wetlands. We suggest that gas hydrates in fractures and pockets of the carbonate rocks in the permafrost zone became unstable due to warming from the surface. This process may add unknown quantities of methane to the atmosphere in the near future.

Curing a Malignant Climate

“…For example, fires in the Arctic circle deposit soot on the ice, meaning it absorbs more sunlight, heating it up and causing more to melt [9]. The permafrost is also melting, releasing tonnes of methane [10] e a greenhouse gas that is 25 times more effective than carbon dioxide e causing more heating. At the same time, the species extinction rate is between 100 and 1000 times background [11], and we know that biodiversity is essential to support our agricultural systems.…”

On the influence of underlying elevation data on Sentinel-5 Precursor TROPOMI satellite methane retrievals over Greenland

“…16). Such features can be easily misinterpreted as a local methane emission signal (see Froitzheim et al, 2021).…”

Inside the Anthropo-Populo-Consumo-Capitalocene

“…Or take the example of methane, a potent if shorter lived greenhouse gas (Fewster et al 2022). The already ongoing methane releases from thawing permafrost regions (Hugelius et al 2020) and the sea floor (Froitzheim et al 2021) contribute to the warming of the Arctic. This will probably trigger additional massive releases of methane from biomass and geological deposits once the loss of permafrost enabling temperatures across almost all of the Eurasian Arctic materialises, which is expected to happen before 2040.…”