How to count methane emissions by 1kiki

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How to count methane emissions

POSTED BY: 1KIKI
UPDATED: Monday, April 28, 2014 21:27
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Monday, April 28, 2014 12:19 PM

Goodbye, kind world (George Monbiot) - In common with all those generations which have contemplated catastrophe, we appear to be incapable of understanding what confronts us.

http://www.rdmag.com/news/2014/04/how-count-methane-emissions?et_cid=3
908165&et_rid=366206770&type=headline

How to count methane emissions

In formulating policies to address greenhouse gas emissions, or evaluating the potential impact of different energy technologies on global climate change, one of the thorniest issues is how to account for the very distinctive characteristics of various different gases.

For example, methane is a potent greenhouse gas, as well as a significant byproduct of using natural gas—advocated by many as a “bridge” to a lower-emissions future. But a direct comparison between methane and carbon dioxide, the most abundant greenhouse gas emitted by human activities, is complicated: While the standard figure used for emissions trading and technology evaluation says that, gram for gram, methane is about 30 times as potent a greenhouse gas as carbon dioxide, scientists say that’s an oversimplification.

As reported in a paper published in Nature Climate Change, authored by Massachusetts Institute of Technology (MIT) Asst. Prof. of Engineering Systems Jessika Trancik and doctoral student Morgan Edwards, this conversion factor (called the global warming potential, or GWP) may significantly misvalue methane. Getting this conversion factor right is challenging because methane’s initial impact is much greater than that of carbon dioxide—by about 100 times. But methane only stays in the atmosphere for a matter of decades, while carbon dioxide sticks around for centuries. The result: After six or seven decades, the impact of the two gases is about equal, and from then on methane’s relative role continues to decline.

Static measures, such as the GWP, give a false sense of the gases’ impacts, and could lead to unintended climate outcomes when used as the basis for policies and planning, Trancik says. Instead, she and Edwards argue for the use of what they call “dynamic metrics,” which lead to a conversion factor that changes over time in a predictable way.

“With carbon dioxide, one cares about the cumulative emissions,” Trancik says. “But with methane, the timing of emissions matters.” The issue for regulators and planners, she says, is: “How can we take emissions timing into account, in a metric equation that is simple and predictive enough to be used?”

The authors develop a kind of metric that incorporates limited information about the future—an intended “stabilization level” for the Earth’s climate—but doesn’t require knowledge about the exact climate scenario to be followed. The researchers develop two such metrics, the instantaneous climate impact (ICI) and the cumulative climate impact (CCI); the latter is more conservative in earlier years.

The paper shows that the choice of how to quantify the effect of methane versus carbon dioxide can have a bigger effect on the ultimate climate outcomes than uncertainties in how much leakage of methane occurs in the natural gas production system, which has recently drawn much more attention from researchers and policymakers. For this reason it is important to choose an accurate metric, and understand its properties.

“Any equivalency metric is going to be imperfect,” Trancik says, “which is why it is important to test metrics and understand their properties.” But using a measure that accounts for significant changes to the climate over time should allow for more realistic assessments of the effects of policy decisions—such as in setting environmental regulations, or deciding where to focus research investment.

While it is generally assumed that the climate impact of natural gas to produce electricity is approximately half that of coal, she says, that comparison depends on timing: The figure is true today, but within three decades, compared with coal-fired power plants, the advantage of natural gas is roughly halved under common stabilization goals. Similarly, compressed natural gas as a transportation fuel actually ends up being worse than gasoline within a couple of decades, the authors report.

In the case of natural gas, it’s not the emissions from the plants burning the gas that produce methane; rather, it is the leakage of methane—the main component of natural gas—during drilling and transportation of the fuel. So there is potential to reduce the impact of natural gas by investing in better control of such leakage, Trancik says.

More accurate comparisons of the effects of methane and carbon dioxide can also be important when evaluating technologies that produce emissions of more than one type of gas. For example, the study found that algae-based biofuels that incorporate a biodigester may leak enough methane to outweigh the emissions benefits over corn ethanol—a consideration that may weigh on decisions about which technology designs should be invested in and how they should be regulated, she says.

Source: Massachusetts Institute of Technology

OONJERAH - We are too dumb to live and smart enough to wipe ourselves out.

"You, who live in any kind of comfort or convenience, do not know how these people can survive these things, do you? They will endure because there is no immediate escape from endurance. Some will die, the rest must live."

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Monday, April 28, 2014 12:31 PM

JONGSSTRAW

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Monday, April 28, 2014 6:00 PM

KPO

Sometimes you own the libs. Sometimes, the libs own you.

Interesting, I should've liked to see some figures in this article though.

It's not personal. It's just war.

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Monday, April 28, 2014 6:05 PM

1KIKI

Goodbye, kind world (George Monbiot) - In common with all those generations which have contemplated catastrophe, we appear to be incapable of understanding what confronts us.

While the articles can point you to interesting information, to get the full picture you need to purchase the papers. Generally it runs USD35.00

http://www.nature.com/nclimate/journal/v4/n5/full/nclimate2204.html

OONJERAH - We are too dumb to live and smart enough to wipe ourselves out.

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Monday, April 28, 2014 8:30 PM

OONJERAH

Overwhelmed.

"How to count methane emissions for Dummies?"

Me: The build up of carbon dioxide in our atmosphere is believed to
be a cause of global warming as well as a pollutant that threatens
the health of life forms that have to breath it. Recently I learned
that methane is a similar threat.

Kiki, the OP article may seem simple to you. But I cannot read &
comprehend it. I'm only smart about 1 or 2 things, and chemistry
isn't one of them.

I've been concerned about all the anti-conservation things we do
since I was very young, 50 years or so. When the term Global
Warming came into common use, I paid attention. Two reasons, I
guess: 1. You can only crap in your mess gear so much before you
have to pay the price in loss of health. 2. I lived near 2 decades in
a logging town at 4,000 ft. Common knowledge was that as soon
as the dogwood trees bloomed, it meant the last snow-fall of the
season was imminent. One year, the dogwood bloomed, but we got
no snow. I took that as a sign of climate change.

I can't grasp the complexities of this at all. I won't attempt to read
science papers.
Has to be very simple for me. Visible!
The smog in L.A., the No snow on Mt. Kilimanjaro, the No glaciers
in Glacier National Park ... I understand pictures.

... oooOO}{OOooo ...

I've given up looking for the meaning of life. Now all I want is a cookie.

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Monday, April 28, 2014 9:08 PM

1KIKI

Goodbye, kind world (George Monbiot) - In common with all those generations which have contemplated catastrophe, we appear to be incapable of understanding what confronts us.

Hello OONJERAH

I think you learn by different means. I find it a fascinating process that I don't understand, but respect anyway. Your voice is a valuable one imo and I like to hear it.

OONJERAH - We are too dumb to live and smart enough to wipe ourselves out.

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Monday, April 28, 2014 9:27 PM

JONGSSTRAW

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