Global Warming Aided by Water

By: Mason Wynder

Recently researchers from Washington State University have stated that reservoirs are a major producer of greenhouse gasses; producing one gigaton of carbon dioxide a year. This is more greenhouse gasses then are produced in all of Canada. This is due because unlike natural bodies of water, a reservoir is man made by flooding a piece of land. As the plants break down the release carbon dioxide, they also receive more organic material from rivers this only continues the cycle of plants decomposing and producing these harmful gases. Now the reservoirs do are a source of very useful resources such as such as water, power, and flood control. But it also causes other harms to the eco system. More recent studies have looked at such reservoirs that supply these resources, and found that they emit almost as much greenhouse gasses as reservoirs behind power stations. Now the reservoirs that produce the most greenhouse gasses are the younger tropical ones. The older more northern reservoirs produce less of the harmful gasses. But it all comes down to how biologically productive the reservoirs are. If they produce more than the more gasses they will produce. https://www.sciencedaily.com/releases/2016/10/161003132626.htm

In this article I will examine the evidence of reservoirs emitting the harmful greenhouse gasses. 

Scientific American reports that more than twenty percent of all man made methane gasses come from reservoirs. Because there is so little data on this subject it is still a huge question mark as to how much exactly the reservoirs produce. However one estimate is that global reservoirs produce 104 teragrams of methane annually, compare to NASA’s estimate that burning fossil fuels produces between 80 to 120 grams annually. This is an astonishing amount, just seeing how the reservoirs compare fossil fuels is alarming. In a study conducted on Harasha Lake in 2012 found that it produced more methane that year than any other reservoir in the United States. Thus showing that a lake in the north can still produce a high amount of methane if there is enough vegetation around it.   https://www.scientificamerican.com/article/methane-emissions-may-swell-from-behind-dams/

In an article published by science magazine they discuss the effect that the, so called, clean energy generated by hydroelectric dams may not be so clean. The methane produced by these dams is a total of 1.3% of the entire worlds greenhouse emissions;  the same amount as produced by Canada. There are approximately 847 large dams in operation, and many more ready to be built this could spell out a huge problem for the world. But there is a way to cut down on such harmful gasses, by building the dams on rivers with low amounts of nutrients which wouldn’t be able to sustain growth of vegetation preventing the creation of methane and other such harmful gasses.   http://www.sciencemag.org/news/2016/09/hundreds-new-dams-could-mean-trouble-our-climated

A new hydroelectric dam is often the subject of scrutiny, due to its disruption of the beauty of the world. But the other effects such a dam has may far out way the “green effects” of this energy providing tool. These dams emit the gas known as methane. These gasses can be released in many different ways such as bubbles on the water’s surface, or as the water travels through the hydroelectric turbines, or may be released farther upstream.  It is possible to cut these gasses down immensely buy building these dams in areas that are deeper. Buy building the dams deeper it covers less service area there by causing the decomposition of less greenery, producing less methane and carbon dioxide.  http://www.eenews.net/stories/1059991386

Now the amount of greenhouse gasses produced is also caused by a number of differing factors. Such as how old the reservoir is, climate and other varying factors. Causing the study of such places to be difficult; as well as making it hard to decide where to build one of these dams to make it the most “green”. http://www.sciencedirect.com/science/article/pii/S1872203214000249

One main reason that the methane escapes from the water is during a drawdown, this is when the water level is severely lowered. This exposes the decayed plants to the air and allows the methane to escape. A drawdown can produce up to 20 times more methane then normal. https://thinkprogress.org/study-reservoirs-may-produce-20-times-more-methane-than-normal-during-water-drawdown-77613f70b73b#.vdgj5dkx1

(Fig 1) Showing a detailed example of how the gasses escape into the atmosphere, and their effect. https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjPybXqwOjPAhXKsVQKHdQPDU0QjRwIBw&url=http%3A%2F%2Fwww.globalresearch.ca%2Farctic-methane-release-and-global-warming%2F5344315&bvm=bv.136499718,d.cGw&psig=AFQjCNGVT-gp9sOQ6qAhjpn1cnle6IHjAw&ust=1477022765461182

(Fig 2) Showing the effects of Drawdown as well as how the gasses escape from the water. https://www.internationalrivers.org/campaigns/reservoir-emissions

After researching this topic, I find that the statement is in fact true. That the dams and reservoirs are doing, in some cases, more harm than good to the environment, now there are things we can do to lower the amount of methane that is produced but we must find a way to produce truly clean energy. Then we can have the power we so desperately need but also preserve our earth that we must live on. This study has allowed me to take a better look at some of the ways we obtain energy, and which ways are better than others.