PNAS2013-12-06 2:03 AM

Anthropogenic emissions of methane in the United States

Abstract
This study quantitatively estimates the spatial distribution of anthropogenic methane sources in the United States by combining comprehensive atmospheric methane observations, extensive spatial datasets, and a high-resolution atmospheric transport model. Results show that current inventories from the US Environmental Protection Agency (EPA) and the Emissions Database for Global Atmospheric Research underestimate methane emissions nationally by a factor of ∼1.5 and ∼1.7, respectively. Our study indicates that emissions due to ruminants and manure are up to twice the magnitude of existing inventories. In addition, the discrepancy in methane source estimates is particularly pronounced in the south-central United States, where we find total emissions are ∼2.7 times greater than in most inventories and account for 24 ± 3% of national emissions. The spatial patterns of our emission fluxes and observed methane–propane correlations indicate that fossil fuel extraction and refining are major contributors (45 ± 13%) in the south-central United States. This result suggests that regional methane emissions due to fossil fuel extraction and processing could be 4.9 ± 2.6 times larger than in EDGAR, the most comprehensive global methane inventory. These results cast doubt on the US EPA’s recent decision to downscale its estimate of national natural gas emissions by 25–30%. Overall, we conclude that methane emissions associated with both the animal husbandry and fossil fuel industries have larger greenhouse gas impacts than indicated by existing inventories.

KEYWORDS

SHARE & LIKE

COMMENTS

ABOUT THE AUTHOR

PNAS

0 Following 4 Fans 0 Projects 58 Articles

SIMILAR ARTICLES

AbstractIn animal communication research, vocal labeling refers to incidents in which an animal consistently uses a specific acoustic signal when prese

Read More

AbstractWe show that easily accessible digital records of behavior, Facebook Likes, can be used to automatically and accurately predict a range of high

Read More

意义2010年 墨西哥湾北部深水地平线(MC252)灾难泄漏了超过400万桶原油。石油从海底架上升到了有许多大型中上层鱼类产卵的表层。在此我们描述了现场采集油样对包括蓝鳍金枪鱼,黄鳍金枪鱼和琥珀鱼在内的温水掠食动物迅速发育胚胎的影响。对于每个物种,环境相关MC252原油泄漏造成了心脏发育的严重缺陷。此

Read More

Abstract In the last decade there has been an exponential increase in knowledge about the genetic basis of complex human traits, including neuropsychi

Read More

AbstractGold mining has rapidly increased in western Amazonia, but the rates and ecological impacts of mining remain poorly known and potentially under

Read More

Abstract The interrelationships between hydrologically driven evolution of legacy landscapes downstream of major mining districts and the contaminatio

Read More

Abstract Changes in global (ocean and land) precipitation are among the most important and least well-understood consequences of climate change. Incre

Read More

AbstractAntiangiogenic therapy has shown clear activity and improved survival benefit for certain tumor types. However, an incomplete understanding of

Read More

AbstractThe biological mechanisms underlying long-term partner bonds in humans are unclear. The evolutionarily conserved neuropeptide oxytocin (OXT) is

Read More

Abstract Wine grapes present a unique biogeography model, wherein microbial biodiversity patterns across viticultural zones not only answer questions

Read More