Source: Journal of Geophysical Research-Biogeosciences, doi:10.1002/jgrg.20086, 2013 http://onlinelibrary.wiley.com/doi/10.1002/jgrg.20086/abstract
Title: K-Pg extinction patterns in marine and freshwater environments: The impact winter model
Authors: Douglas S. Robertson: Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA;
William M. Lewis: Department of Ecology and Evolutionary Biology and Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA;
Peter M. Sheehan: Milwaukee Public Museum, Milwaukee, Wisconsin, USA;
Owen B. Toon: Department of Atmospheric and Oceanic Sciences and Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado, USA.
2. Constraining bubbling of methane from thermokarst lakes
In northern thermokarst lakes, which form in depressions left as permafrost thaws, methane, a greenhouse gas, can be released from lake sediments to the atmosphere through bubbling, or ebullition. Constraining the amount of methane released through bubbling would help scientists understand the role of thawing permafrost in the carbon cycle and global climate change. However, bubbling is highly variable in both space and time and thus difficult to measure accurately, so there are large uncertainties in estimates of methane emissions from northern ecosystems.
Walter Anthony and Anthony sought to better understand the spatial distribution of bubbling in lakes. They note that in many northern lakes, the bubbling sources, which they call ebullition seeps, cluster together in regular spatial patterns. They combine field data from individual seeps with models to
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American Geophysical Union