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We present high resolution measurements of atmospheric methane (CH4) and nitrogen isotopic composition (d15N-N2) in the Greenland Ice Sheet Project Two (GISP2) Ice core. The data span Marine Isotope Stage 3, 13 to 50 thousand years (ka) before present. These datasets enhance our understanding of abrupt climate variability during the last glacial period, with a focus on Heinrich events 1 through 5. CH4 data were analyzed between 2014 and 2020 via an established wet extraction technique (Mitchell et al. 2013). Concentrations were determined via gas chromatography measurements on an Agilent 6890N and calibrated to the NOAA04 scale. d15N-N2 data were measured between 2017 and 2020 on a Finnigan MAT Delta XP via an established technique (Petrenko et al. 2006). The methane data allow for gas-phase synchronization of the GISP2 ice core to other polar ice cores from Greenland and Antarctica. The nitrogen isotopic composition data allow for reconstruction of abrupt Greenland surface climate variations.
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Carbonyl sulfide (COS) measurements from the Greenland Ice Sheet Project 2 D and B (GISP2D and GISP2B) ice cores using dry and wet extraction methods, 2015-2025
Measurements were conducted to determine the carbonyl sulfide levels in ancient air preserved in the Greenland ice sheet using samples from the GISP2D and GISP2B ice cores from Summit, Greenland. The GISP2D is a fluid-drilled core and the GISP2B is a dry-drilled core. This data set includes four CSV files. Most of the measurements are from the GISP2D ice core and 3 out of the 4 data files associated with this submission include data from the GISP2D. Both dry and wet extraction methods were used to extract the ice core air. All dry extraction-based GISP2D data are presented in one file. The wet extraction-based data are split between 3 data files: 1) GISP2B data, 2) shallow GISP2D data, 3) deep GISP2D data. The shallow and deep wet extraction-based GISP2D data are presented in 2 separate files despite including some overlapping depths because the measurements were conducted over different time periods. All data are depth-coded and presented "as measured" with associated 1 sigma uncertainties after having gone through a preliminary quality control and having been finalized in terms of calibration. Note that the wet extraction-based measurements require a solubility correction before they can be compared with the dry extraction-based measurements from the same depths.
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- Award ID(s):
- 1839506
- PAR ID:
- 10616473
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- carbonyl sulfide in ice cores ice core gas records trace gas measurements in Greenland ice cores sulfur gases in ice cores carbonyl sulfide
- Format(s):
- Medium: X Other: text/xml
- Institution:
- UC Irvine
- Sponsoring Org:
- National Science Foundation
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We present new measurements of methane (CH4), nitrogen isotopes (d15N-N2), and total air content (TAC) from the North Greenland Eemian Ice Drilling (NEEM), North Greenland Ice Core Project (NGRIP), and Greenland Ice Sheet Project Two (GISP2) Greenland ice cores from the Last Glacial Maximum through the late Holocene (0 to ~18 thousand years before present [ka BP]). These records provide insight into spatial pattern of Greenland climate evolution across the deglaciation and the Holocene Thermal Maximum. The methane data allow for gas-phase synchronization of ice cores across Greenland and Antarctica, providing empirical delta age reconstructions. The nitrogen isotopic composition data allow for reconstruction of abrupt Greenland surface climate variations, which is provided for all 3 sites. Data are a combination of measurements conducted at Oregon State University, Scripps Institution of Oceanography, and the National Institute for Polar Research using previously established techniques.more » « less
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