sibeen said:
PermeateFree said:
mollwollfumble said:
As thought by the Greens?
This is the third time I’ve heard this news, it isn’t new.
Reading a little more:
>>Researchers have monitored this phenomenon over the last 15 years or so, but a paper to be published this week by scientists at Washington State University will be the largest and most comprehensive to date. The team has gone over the previous literature and synthesized a large number of studies, concluding that not only are these emissions equal to 1.3 percent of the global total, but the particularly potent greenhouse gas methane is a bigger part of the picture than previously suspected.<<
So to put that in a bit of perspective; methane accounts for approximately 30% of the warming induced by greenhouse gases. Reservoirs contribute 1.3% of the methane. So about 0.4 – 0.5% of greenhouse warming can be attributed to reservoirs.
Oh look! There is even more in the article:
“Methane is less soluble in water than are the other greenhouse gases included in this study (carbon dioxide and nitrous oxide),” Deemer tells us. “Because of this, a large fraction of methane emission can occur as bubbles. If these bubbles aren’t captured by measurements, reservoir methane flux can be underestimated.”
The scientists say that these bubbles can make up over 95 percent of methane emissions from some systems, but their study is the first to take them into account. The upshot of this is that reservoirs are emitting 25 percent more methane than we previously thought. But on a more positive note, the researchers tell us that this new knowledge may help us come up with ways to lessen the impact.
“Because reservoirs are human designed and human operated, there may be an opportunity for greenhouse gas mitigation at both the planning and the operation stages,” says Deemer. “The results of our study suggest that reservoirs sited in locations downstream of ‘nutrient’ inputs will produce more methane than those receiving fewer nutrient inputs. Large nutrient inputs to waterways are often associated with human activities like food and energy production. It is also possible that reducing nutrient inputs to existing reservoirs could reduce methane emissions, but this remains to be tested in the field.”