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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.
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Greenland Ice Sheet Project Two (GISP2) ice core methane (CH4) and nitrogen isotopic composition (d15N-N2), 13-50 ka BP
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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- PAR ID:
- 10485513
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- ICE CORE RECORDS METHANE NITROGEN ISOTOPES GREENLAND GISP2
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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