| Summary: | Ethane and acetylene are non-methane hydrocarbons released from combustion processes, with shared sources from fossil fuel use, biofuel and biomass burning. Ethane is also thought to have a source through natural geologic outgassing (Etiope and Ciccioli, 2009). Ethane and acetylene levels in the atmosphere can be used to quantify the variability in fossil fuel and biomass burning through time. In this project, paleo-atmospheric levels of ethane and acetylene were co-measured in the air bubbles of polar ice cores using a wet-extraction (melt) method (see Nicewonger et al., 2016 GRL (Geophysical Research Letters), Nicewonger et al., 2018 PNAS, or Nicewonger, 2019 PhD thesis). Ice core samples from Summit, Greenland (GISP2B, GISP2D), and West Antarctic Ice Sheet (WAIS) Divide, Antarctica (WDC05A, WDC06A) and South Pole, Antarctica (SPC14) were analyzed covering the last 2,000 years (~0 –1900 Common Era). The paleo-atmospheric ethane levels from this project allowed for the reconstruction of biomass burning ethane emissions over the last 1,000 years (see Nicewonger et al., 2018 PNAS publication). Please refer to the corresponding manuscript for more information on the “_Ethane.txt” data and how the gas ages were calculated (Nicewonger et al., 2018 PNAS SI Appendix). The ethane data have been since updated (Aug. 2019) with new analytical blank corrections, resulting in slightly different mixing ratios than what is reported in the Nicewonger et al., 2018 PNAS (Proceedings of the National Academy of Sciences) publication. Please use the updated dataset for future analysis ("site_EthaneAcetylene_2ky.txt") The acetylene levels measured may be impacted by solubility loss in the melt water during the wet-extraction method. The correction factor for this loss is about 1.15. Both solubility corrected and uncorrected data are available in the data sets. Missing or excluded data are denoted with -999.0.
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