Abstract
Determining the sources of methane emissions in the Arctic remains a complex problem, due to their heterogeneity and diversity. Information on the amount of emissions has significant uncertainties and may differ by an order of magnitude in various literature sources. Measurements made in the immediate vicinity of emission sources help to clarify emissions and reduce these uncertainties. This paper analyzes the data of three expeditions, carried out in the western Arctic seas during Arctic spring, summer, and early autumn in 2021, which obtained continuous data on the concentration of methane and its isotope signature δ13C. CH4 concentrations and δ13C displayed temporal and spatial variations ranging from 1.952 to 2.694 ppm and from −54.7‰ to −40.9‰, respectively. A clear correlation was revealed between the surface methane concentration and the direction of air flow during the measurement period. At the same time, even with advection from areas with a significant anthropogenic burden or from locations of natural gas mining and transportation, we cannot identify particular source of emissions; there is a dilution or mixing of gas from different sources. Our results indicate footprints of methane sources from wetlands, freshwater sources, shelf sediments, and even hydrates.
Highlights
In [4,5,12], it was concluded that the East Siberian Arctic Shelf (ESAS) gives from 10 to 17 Tg yr−1 on the basis of data from a number of marine expeditions
As expected, during the period covered by the research, a significant influence on the methane concentration variability in the lower atmosphere is determined mainly by large-scale processes, namely by the direction of air masses advection
The minimum methane concentration during the expeditions occurred in Arctic spring and summer, observed due to air mass removal from the west direction
Summary
Significant reserves of methane are concentrated in the Arctic region, including the water column and seabed; some of the marine sources are poorly investigated. Various estimates of methane emissions from the sea surface at high latitudes differ by more than three orders of magnitude: from 0.013 to 20 Tg yr−1 [1–8]. In [4,5,12], it was concluded that the East Siberian Arctic Shelf (ESAS) gives from 10 to 17 Tg yr−1 on the basis of data from a number of marine expeditions. In [3], the contribution of methane hydrates to atmospheric emissions was estimated at
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
