Long-term decline of global atmospheric ethane concentrations and implications for methane

  title={Long-term decline of global atmospheric ethane concentrations and implications for methane},
  author={Isobel J. Simpson and Mads P. Sulbaek Andersen and Simone Meinardi and Lori Bruhwiler and Nicola J. Blake and Detlev Helmig and F. Sherwood Rowland and Donald Ray Blake},
After methane, ethane is the most abundant hydrocarbon in the remote atmosphere. It is a precursor to tropospheric ozone and it influences the atmosphere’s oxidative capacity through its reaction with the hydroxyl radical, ethane’s primary atmospheric sink. Here we present the longest continuous record of global atmospheric ethane levels. We show that global ethane emission rates decreased from 14.3 to 11.3 teragrams per year, or by 21 per cent, from 1984 to 2010. We attribute this to… Expand
Three decades of global methane sources and sinks
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Natural gas fugitive emissions rates constrained by global atmospheric methane and ethane.
NG industry representative FER is estimated using global atmospheric methane and ethane measurements over three decades, and literature ranges of tracer gas atmospheric lifetimes, non-NG source estimates, and fossil fuel fugitive gas hydrocarbon compositions suggest an upper bound global average FER of 5% during 2006-2011, and a most likely FE of 2-4% since 2000, trending downward. Expand
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Temporary pause in the growth of atmospheric ethane and propane in 2015–2018
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Measurements in firn (perennial snowpack) air from Greenland and Antarctica are used to reconstruct the atmospheric variability of ethane (C2H6) during the twentieth century, finding that this variability was primarily driven by changes in ethane emissions from fossil fuels. Expand
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Earth's Degassing: A Missing Ethane and Propane Source
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