Skip to main content
Publications | Persons | Institutes | Projects
[ report an error in this record ]basket (0): add | show Print this page

Physical controls of dynamics of methane venting from a shallow seep area west of Svalbard
Silyakova, A.; Jansson, P.G.; Serov, P.; Ferré, B.; Pavlov, A.K.; Hattermann, T.; Graves, C.A.; Platt, S.M.; Myhre, C.L.; Gründger, F.; Niemann, H. (2020). Physical controls of dynamics of methane venting from a shallow seep area west of Svalbard. Cont. Shelf Res. 194: 104030. https://dx.doi.org/10.1016/j.csr.2019.104030

Additional data:
In: Continental Shelf Research. Pergamon Press: Oxford; New York. ISSN 0278-4343; e-ISSN 1873-6955, more
Peer reviewed article  

Available in  Authors 

Author keywords
    Gas seepage; Water masses; Stratification; Multiyear variability; Methane flux; Eddies; Ocean model; Svalbard shelf

Authors  Top 
  • Silyakova, A.
  • Jansson, P.G.
  • Serov, P.
  • Ferré, B.
  • Pavlov, A.K.
  • Hattermann, T.
  • Graves, C.A.
  • Platt, S.M.
  • Myhre, C.L.
  • Gründger, F.
  • Niemann, H., more

Abstract
    We investigate methane seepage on the shallow shelf west of Svalbard during three consecutive years, using discrete sampling of the water column, echosounder-based gas flux estimates, water mass properties, and numerical dispersion modelling. The results reveal three distinct hydrographic conditions in spring and summer, showing that the methane content in the water column is controlled by a combination of free gas seepage intensity and lateral water mass movements, which disperse and displace dissolved methane horizontally away from the seeps. Horizontal dispersion and displacement of dissolved methane are promoted by eddies originating from the West Spitsbergen Current and passing over the shallow shelf, a process that is more intense in winter and spring than in the summer season. Most of the methane injected from seafloor seeps resides in the bottom layer even when the water column is well mixed, implying that the controlling effect of water column stratification on vertical methane transport is small. Only small concentrations of methane are found in surface waters, and thus the escape of methane into the atmosphere above the site of seepage is also small. The magnitude of the sea to air methane flux is controlled by wind speed, rather than by the concentration of dissolved methane in the surface ocean.

All data in the Integrated Marine Information System (IMIS) is subject to the VLIZ privacy policy Top | Authors