Navigation Links
Scientists question EPA estimates of greenhouse gas emissions

MADISON, WI, June, 2010 The approach the U.S. Environmental Protection Agency (EPA) uses to estimate greenhouse gas emissions from agricultural anaerobic lagoons that treat manure contains errors and may underestimate methane emissions by up to 65%, according to scientists from the University of Missouri.

Anaerobic lagoons treat manure on some animal feeding operations prior to application to crops as a fertilizer. Methane, one byproduct of the treatment process, has 21 times the warming potential of carbon dioxide.

A 2007 U.S. Supreme Court ruling mandated the EPA consider greenhouse gases a pollutant. This led the EPA in 2009 to approve greenhouse gas reporting requirements for any facility that annually releases 25,000 metric tons or more of carbon dioxide equivalents to the atmosphere. The objective of these reporting requirements is to quantify emissions as a first step towards developing strategies to reduce greenhouse gas losses.

Direct measurements of methane emissions from anaerobic lagoons are technically difficult and very expensive, so the EPA adopted a calculation method to estimate methane emissions from anaerobic digesters. They relied on the method used by the International Panel on Climate Change (IPCC) in their 2006 worldwide estimate of greenhouse inventories.

An interdisciplinary team of scientists from the University of Missouri evaluated the EPA and IPCC approach to estimate greenhouse emissions from anaerobic lagoons. They reported the results of their analysis in the May-June 2010 issue of Journal of Environmental Quality, published by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.

The team documented errors in the approach, which the EPA and IPCC adapted from a method used to estimate methane production from anaerobic digesters. A literature review of the performance of uncovered anaerobic lagoons indicated that there are important difference between anaerobic lagoons and anaerobic digesters that were not accounted for in the EPA and IPCC approach. They found that uncovered anaerobic lagoons were more efficient at converting waste to methane than predicted using literature based on digesters. The team also found mistakes the equations that the EPA and IPCC used.

John Lory, a member of the team that reviewed the EPA rule, said "Our calculated estimates of methane emissions from anaerobic lagoons indicated that the EPA approach could substantially underestimate methane emissions from these facilities, perhaps by as much as 65%."

The report also suggested that some other operations currently excluded under the rules may in fact produce emissions beyond the threshold. Manure storage facilities are the only on-farm source required to report under the current rules. The most likely manure storage facilities to meet the current reporting requirements are anaerobic lagoons. EPA projected that operations with more than 3,200 dairy cows or 34,100 pigs would likely meet the reporting requirement.

Lory emphasized that there have been few direct measurements of methane emissions from anaerobic lagoons and the few measurements that exist indicate that both the University of Missouri calculated estimate and the EPA calculated estimate of methane loss from these facilities may be high.

Though the research team outlined a different approach to measuring methane emissions, but pointed out that understanding of anaerobic lagoons is still evolving. "More research is needed before we can provide accurate estimates of methane losses from anaerobic lagoons," added Lory.


Contact: Sara Uttech
American Society of Agronomy

Related biology news :

1. Scientists create 3-D models of whole mouse organs
2. American team of scientists help protect Guatemalas Lake Atitlan
3. Underwater gliders may change how scientists track fish
4. Scientists call for a new strategy for polar ocean observation
5. 21 of Americas top early-career scientists named 2010 Pew Scholars in the biomedical sciences
6. Team of UC scientists awarded $2 million NIH grant for better flu diagnoses
7. UM School of Medicine scientists find hormone influences sensitivity to sweetness
8. Scientists locate oil plume extending toward Dry Tortugas
9. UMCES Horn Point Laboratory scientists to study oil spill effects in Gulf of Mexico
10. Forsyth scientists support the Human Microbiome Project
11. Scripps Research scientists find new way to attack cancerous cells
Post Your Comments:
(Date:6/9/2016)... 2016  Perkotek an innovation leader in attendance control systems is proud to announce ... for employers to make sure the right employees are actually signing in, and to ... ... ... ...
(Date:6/2/2016)... 2, 2016 The Department of Transport ... the 44 million US Dollar project, for the , ... including Personalization, Enrolment, and IT Infrastructure , to ... production and implementation of Identity Management Solutions. Numerous renowned international ... Decatur was selected for the most compliant ...
(Date:5/24/2016)... , May 24, 2016 Ampronix facilitates superior patient care by providing unparalleled ... medical LCD display is the latest premium product recently added to the range of ... ... ... Sony 3d Imaging- LCD Medical Display- Ampronix News ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... June 23, 2016 , ... ... (Yeast and Mold) microbial test has received AOAC Research Institute approval 061601. , ... tests introduced last year,” stated Bob Salter, Vice President of Regulatory and Industrial ...
(Date:6/23/2016)... SAN FRANCISCO , June 23, 2016   ... it has secured $1 million in debt financing from ... to ramp up automation and to advance its drug ... for its new facility. "SVB has been ... goes beyond the services a traditional bank would provide," ...
(Date:6/23/2016)... ... June 23, 2016 , ... In a new case ... Denmark detail how a patient who developed lymphedema after being treated for breast cancer ... could change the paradigm for dealing with this debilitating, frequent side effect of cancer ...
(Date:6/23/2016)... 23, 2016 Andrew ... Published recently in ... journal from touchONCOLOGY, Andrew D Zelenetz , ... cancer care is placing an increasing burden on ... biologic therapies. With the patents on many biologics ...
Breaking Biology Technology: