A conduit dilation model of methane venting from lake sediments

Date
2011-03-26Author
Scandella, Benjamin P.
Concept link
Varadharajan, Charuleka
Concept link
Hemond, Harold F.
Concept link
Ruppel, Carolyn D.
Concept link
Juanes, Ruben
Concept link
Metadata
Show full item recordCitable URI
https://hdl.handle.net/1912/4454As published
https://doi.org/10.1029/2011GL046768DOI
10.1029/2011GL046768Keyword
Greenhouse gas; Methane flux; Freshwater methane; Gas conduits; Effective stress; EbullitionAbstract
Methane is a potent greenhouse gas, but its effects on Earth's climate remain poorly constrained, in part due to uncertainties in global methane fluxes to the atmosphere. An important source of atmospheric methane is the methane generated in organic-rich sediments underlying surface water bodies, including lakes, wetlands, and the ocean. The fraction of the methane that reaches the atmosphere depends critically on the mode and spatiotemporal characteristics of free-gas venting from the underlying sediments. Here we propose that methane transport in lake sediments is controlled by dynamic conduits, which dilate and release gas as the falling hydrostatic pressure reduces the effective stress below the tensile strength of the sediments. We test our model against a four-month record of hydrostatic load and methane flux in Upper Mystic Lake, Mass., USA, and show that it captures the complex episodicity of methane ebullition. Our quantitative conceptualization opens the door to integrated modeling of methane transport to constrain global methane release from lakes and other shallow-water, organic-rich sediment systems, and to assess its climate feedbacks.
Description
Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 38 (2011): L06408, doi:10.1029/2011GL046768.
Collections
Suggested Citation
Geophysical Research Letters 38 (2011): L06408Related items
Showing items related by title, author, creator and subject.
-
Instability and freezing in a solidifying melt conduit
Holmes-Cerfon, Miranda C.; Whitehead, John A. (2010-10-23)Previous works have shown that when liquid flows in a pipe whose boundary temperature is below freezing, a tubular drainage conduit forms surrounded by solidified material that freezes shut under the appropriate combination ... -
The Iceland-Faroe slope jet: a conduit for dense water toward the Faroe Bank Channel overflow
Semper, Stefanie; Pickart, Robert S.; Våge, Kjetil; Larsen, Karin Margretha H.; Hátún, Hjálmar; Hansen, Bogi (Nature Research, 2020-10-23)Dense water from the Nordic Seas passes through the Faroe Bank Channel and supplies the lower limb of the Atlantic Meridional Overturning Circulation, a critical component of the climate system. Yet, the upstream pathways ... -
Submarine giant pumice: A window into the shallow conduit dynamics of a recent silicic eruption.
Mitchell, Samuel J.; Houghton, Bruce; Carey, Rebecca; Manga, Michael; Fauria, Kristen; Jones, Meghan R.; Soule, S. Adam; Conway, Chris E.; Wei, Zihan; Giachetti, Thomas (Springer, 2019-06-29)Meter-scale vesicular blocks, termed “giant pumice,” are characteristic primary products of many subaqueous silicic eruptions. The size of giant pumices allows us to describe meter-scale variations in textures and geochemistry ...