Corporate Banner
Satellite Banner
Technology
Networks
Scientific Communities
 
Become a Member | Sign in
Home>News>This Article
  News
Return

How to Count Methane Emissions

Published: Tuesday, April 29, 2014
Last Updated: Tuesday, April 29, 2014
Bookmark and Share
Study provides new metric for comparing the greenhouse gases methane and carbon dioxide.

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 CO2, scientists say that’s an oversimplification.

As reported in a paper published in the journal Nature Climate Change, authored by MIT assistant professor 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 CO2 - by about 100 times.

But methane only stays in the atmosphere for a matter of decades, while CO2 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 CO2, 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 CO2 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 CO2 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.


Further Information

Join For Free

Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 3,000+ scientific posters on ePosters
  • More Than 4,500+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Controlling RNA in Living Cells
Modular, programmable proteins can be used to track or manipulate gene expression.
Wednesday, April 27, 2016
Long-Term Drug Release
New tablet attaches to the lining of the GI tract, resists being pulled away.
Thursday, April 07, 2016
Pharmacy on Demand
New, portable system can be configured to produce different drugs.
Monday, April 04, 2016
A Programming Language for Living Cells
New language lets researchers design novel biological circuits.
Monday, April 04, 2016
Why Some Tumors Withstand Treatment
Mechanism uncovered that allows cancer cells to evade targeted therapies.
Thursday, March 17, 2016
Cancer Cells Remodel Environments Before Spreading
Researchers at MIT have found that the cancer cells remodel their environment to make it easier to reach nearby blood vessels.
Wednesday, March 16, 2016
Paving the Way for Metastasis
Cancer cells remodel their environment to make it easier to reach nearby blood vessels.
Tuesday, March 15, 2016
A New Way to Discover DNA Modifications
Researchers systematically find molecules that help regulate and protect DNA.
Wednesday, March 02, 2016
MIT Study: Carbon Tax Needed to Cut Fossil Fuel Consumption
Researchers at MIT have suggested that the technology-driven cost reductions in fossil fuels will lead the world to continue using all the oil, gas, and coal, unless governments pass new taxes on carbon emissions.
Thursday, February 25, 2016
Mapping Regulatory Elements
Systematically searching DNA for regulatory elements indicates limits of previous thinking
Wednesday, February 03, 2016
Curing Disease by Repairing Faulty Genes
New delivery method boosts efficiency of CRISPR genome-editing system.
Wednesday, February 03, 2016
Living a “Mixotrophic” Lifestyle
Some tiny plankton may have big effect on ocean’s carbon storage.
Tuesday, February 02, 2016
Faster Drug Discovery?
Startup develops more cost-effective test for assessing how cells respond to chemicals.
Friday, January 29, 2016
No More Insulin Injections?
Encapsulated pancreatic cells offer possible new diabetes treatment.
Tuesday, January 26, 2016
Engineering Foe into Friend
Bose Grant awardee Jacquin Niles aims to repurpose the malaria parasite for drug delivery.
Monday, January 25, 2016
Scientific News
The Rise of 3D Cell Culture and in vitro Model Systems for Drug Discovery and Toxicology
An overview of the current technology and the challenges and benefits over 2D cell culture models plus some of the latest advances relating to human health research.
Scientists Find Evidence That Cancer Can Arise Changes
Researchers at Rockefeller University have found a mutation that affects the proteins that package DNA without changing the DNA itself can cause a rare form of cancer.
Developing a More Precise Seasonal Flu Vaccine
During the 2014-15 flu season, the poor match between the virus used to make the world’s vaccine stocks and the circulating seasonal virus yielded a vaccine that was less than 20 percent effective.
A Peachy Defense System for Seeds
ETH chemists are developing a new coating method to protect seeds from being eaten by insects. In doing so, they have drawn inspiration from the humble peach and a few of its peers.
Fighting Cancer with Borrowed Immunity
A new step in cancer immunotherapy: researchers from the Netherlands Cancer Institute and University of Oslo/Oslo University Hospital show that even if one's own immune cells cannot recognize and fight their tumors, someone else's immune cells might.
Modified Microalgae Converts Sunlight into Valuable Medicine
A special type of microalgae can soon produce valuable chemicals such as cancer treatment drugs and much more just by harnessing energy from the sun.
Breakthrough Approach to Breast Cancer Treatment
Scripps scientists have designed a drug candidate that decreases growth of breast cancer cells.
Loss Of Y Chromosome Increases Risk Of Alzheimer’s
Men with blood cells that do not carry the Y chromosome are at greater risk of being diagnosed with Alzheimer’s disease. This is in addition to an increased risk of death from other causes, including many cancers. These new findings by researchers at Uppsala University could lead to a simple test to identify those at risk of developing Alzheimer’s disease.
Making Virus Sensors Cheap and Simple
Researchers at The University of Texas at Austin demonstrated the ability to detect single viruses in a solution containing murine cytomegalovirus (MCMV).
A Guide to CRISPR Gene Activation
A comparison of synthetic gene-activating Cas9 proteins can help guide research and development of therapeutic approaches.
Scroll Up
Scroll Down
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
3,000+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,500+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!