Breaking down the impact of greenhouse gases

October 23, 2012 by Kristin Manke
A-tisket, a-tasket, a better greenhouse gas basket
Flares burn off excess methane at oil and gas refineries, landfills, and other industrial plants. Flares are used to control release of methane into the atmosphere but recovery options are also available that capture methane for use as fuel.

It's called the global warming potential or GWP for short and it bundles together the importance of carbon dioxide, methane, and other greenhouse gases on future climate change.  Researchers from DOE's Pacific Northwest National Laboratory, working at the Joint Global Change Research Institute (JGCRI), found that increasing methane's ranking in the GWP made little difference on the overall outcome of climate change projections. JGCRI is a partnership between PNNL and the University of Maryland.

Carbon dioxide gets most of the press when it comes to greenhouse gas. So much so that it's used as a standard by which researchers and policy makers measure the global warming impact of all other . Though not as abundant, methane, a gas released by oil drilling, landfills, and other industrial activities as well as by nature, is the second most important anthropogenic greenhouse gas and traps more heat in the atmosphere per pound than carbon dioxide.

Considering the shorter lifetime of methane in the atmosphere along with the fact that relatively inexpensive abatement technologies already exist, methane may be an easier emission reduction target. For these reasons, scientists wanted to know if they upped the ante on methane's importance, making it a bigger target for reduction, would it make a difference in climate change projections. The short answer—not that much.

Using the Global Change Assessment Model, an integrated model of the human and Earth system, the researchers found that the impact of changing the value of methane compared to carbon dioxide is relatively small. There are several reasons for this small sensitivity. First, the large amount of relatively low-cost available methane abatement options, which tend to be used in most cases; and second, the interaction between carbon dioxide and methane reductions within the integrated system show that when carbon dioxide is abated, methane is also reduced. This is because reductions in coal or natural gas burning from policies to lower emissions also reduce methane emissions.

Finally, the team noted a third cost in changing the metric.

"The GWP index is already embedded in targets, real-world policies in national and international climate change policy frameworks. Changing this value would have a transition cost, further reducing any benefit a change might provide," said Dr. Steven J. Smith, a senior scientist at JGCRI. "If society wants to reduce , then the key for methane is to put in place incentives for reducing emissions. We found that the exact value placed on was less important."

Explore further: Storage of greenhouse gasses in Siberian peat moor

Related Stories

Storage of greenhouse gasses in Siberian peat moor

January 29, 2007

Wet peat moorlands form a sustainable storage place for the greenhouse gas carbon dioxide but are also a source of the much stronger greenhouse gas methane. According to Dutch researcher Wiebe Borren, peat moorlands will ...

Methane from microbes: a fuel for the future

December 10, 2007

Microbes could provide a clean, renewable energy source and use up carbon dioxide in the process, suggested Dr James Chong at a Science Media Centre press briefing today.

Recommended for you

Ice sheets may be more resilient than thought

September 3, 2015

Sea level rise poses one of the biggest threats to human systems in a globally warming world, potentially causing trillions of dollars' worth of damages to flooded cities around the world. As surface temperatures rise, ice ...

Clues from ancient Maya reveal lasting impact on environment

September 3, 2015

Evidence from the tropical lowlands of Central America reveals how Maya activity more than 2,000 years ago not only contributed to the decline of their environment but continues to influence today's environmental conditions, ...

Climate ups odds of 'grey swan' superstorms

August 31, 2015

Climate change will boost the odds up to 14-fold for extremely rare, hard-to-predict tropical cyclones for parts of Australia, the United States and Dubai by 2100, researchers said Monday.


Adjust slider to filter visible comments by rank

Display comments: newest first

3.7 / 5 (3) Oct 24, 2012
an integrated model of the human and Earth system, the researchers found that the impact of changing the value of methane compared to carbon dioxide is relatively small.

In other words, Global Warming is almost exclusively caused by man burning mined and drilled for fossil fuels.
1.7 / 5 (3) Oct 24, 2012
In other words, Global Warming is almost exclusively caused by man burning mined and drilled for fossil fuels

This article doesn't address that issue.

I think their point was more along the lines of this: Doing something about methane is easier, so what would be the result if we go after the low-hanging fruit first? Their result says that it isn't worth it for several reasons. Their work was not intended to determine the cause of global warming.

I'm not sure if you totally missed the point of the article, or if you are just trolling. Either way, just thought I'd clarify it for you.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.