Methane concentrations of discrete water samples were analyzed using the batch mode of a Greenhouse Gas Analyzer (GGA, Los Gatos Research) following the procedure described by Geprägs (2016). Methane oxidation rate (MOx) measurements were implemented as described by Bussmann et al. (2015) and Mau et al. (2013).Bussmann, I., Matousu, A., Osudar, R., and Mau, S. (2015). Assessment of the radio 3H-CH4 tracer technique to measure aerobic methane oxidation in the water column. Limnol. Oceanogr. Meth. 13, 312-327.Geprägs, P. (2016). Methane environment around cold seeps - examples from Antarctica and the Mediterranean. doctoral thesis, University of Bremen.Mau, S., Blees, J., Helmke, E., Niemann, H., and Damm, E. (2013). Vertical distribution of methane oxidation and methanotrophic response to elevated methane concentrations in stratified waters of the Arctic fjord Storfjorden (Svalbard, Norway). Biogeosciences 10, 6267-6278.