Environment & Energy
Related: About this forumDams And Reservoirs Emit Nearly 1 Billion Tons CO2E Annually - Study
Countries around the world are trying to get their greenhouse gas emissions under control to see them inch down, percentage point by percentage point, from where they stood earlier in the century. If everybody gets on board, and shaves off enough of those percentage points, we just might be able to get on a trajectory to keep the world from warming more than 2 degrees Celsius above the temperature where it stood prior to industrialization.
But if a new study is correct, theres a big problem: There might be more greenhouse gases going into the atmosphere than we thought. That would mean an even larger need to cut.
The new paper, slated to be published next week in BioScience, confirms a significant volume of greenhouse gas emissions coming from a little-considered place: Man-made reservoirs, held behind some 1 million dams around the world and created for the purposes of electricity generation, irrigation, and other human needs. In the study, 10 authors from U.S., Canadian, Chinese, Brazilian, and Dutch universities and institutions have synthesized a considerable body of prior research on the subject to conclude that these reservoirs may be emitting just shy of a gigaton, or billion tons, of annual carbon dioxide equivalents. That would mean they contributed 1.3 percent of the global total.
Moreover, the emissions are largely in the form of methane, a greenhouse gas with a relatively short life in the atmosphere but a very strong short-term warming effect. Scientists are increasingly finding that although we we have begun to curb some emissions of carbon dioxide, the principal greenhouse gas, we are still thwarted by methane, which comes from a diversity of sources that range from oil and gas operations to cows.
EDIT
https://www.washingtonpost.com/news/energy-environment/wp/2016/09/28/scientists-just-found-yet-another-way-that-humans-are-creating-greenhouse-gases/?utm_term=.842e0ee0679b
Agnosticsherbet
(11,619 posts)More work to do.
kristopher
(29,798 posts)The carbon emissions referred to are cyclic and part of the natural carbon cycle. What we're concerned primarily with are emissions from sequestered carbon (AKA FOSSIL FUELS) that are being retrieved from sequestration and released into the environment. Secondarily we're focused on opportunities where we can cause carbon from a natural cycle to be sequestered when it hasn't previously been - on that score research into things like terra pretta agriculture come to mind.
These studies showing carbon flow patterns are important for understanding the system process accurately, but, just like cow farts, the concern included with this type of information is wildly overblown. I wouldn't be a bit surprised to find the study was funded by the fossil fuel/nuclear industry.
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