@article{57827,
  author = {Seongeun Jeong and Dev Millstein and Marc L Fischer},
  title = {Spatially Explicit Methane Emissions from Petroleum Production and the Natural Gas System in California},
  abstract = {<p>We present a new, spatially resolved inventory of methane (CH4) emissions based on US-EPA emission factors and publically available activity data for 2010 California petroleum production and natural gas production, processing, transmission, and distribution. Compared to official California bottom-up inventories, our initial estimates are 3 to 7 times higher for the petroleum and natural gas production sectors but similar for the natural gas transmission and distribution sectors. Evidence from published "top-down" atmospheric measurement campaigns within Southern California supports our initial emission estimates from production and processing but indicates emission estimates from transmission and distribution are low by a factor of approximately 2. To provide emission maps with more accurate total emissions we scale the spatially resolved inventory by sector-specific results from a Southern California aircraft measurement campaign to all of California. Assuming uncertainties are determined by the uncertainties estimated in the top-down study, our estimated state total CH4 emissions are 541 {\textpm} 144 Gg yr{\textendash}1 (as compared with 210.7 Gg yr{\textendash}1 in California{\textquoteright}s current official inventory), where the majority of our reported uncertainty is derived from transmission and distribution. We note uncertainties relative to the mean for a given region are likely larger than that for the State total, emphasizing the need for additional measurements in undersampled regions.</p>},
  year = {2014},
  booktitle = {Environmental Science \& Technology},
  journal = {Environmental Science \& Technology},
  series = {Environmental Science \& Technology},
  volume = {48},
  pages = {5982{\textendash}5990},
  doi = {10.1021/es4046692},
}