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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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High resolution aerosol-related concentrations measured in the archived Greenland Ice Sheet Project Two (GISP2) ice core from 2100 to 2365 meter depth, 2024
The overall objective of this research is to (1) develop high resolution measurements of a range of aerosol-related elements, chemical species, and isotopes in archived Greenland Ice Sheet Project Two (GISP2) ice corresponding to Greenland stadial and interstadial events 5 through 12 from the last Glacial period, and (2) use these measurements -- together with the Goddard Earth Observing System (GEOS)-Chem atmospheric chemistry and other models -- to better understand climate processes and feedbacks underlying rapid climate change events and atmospheric chemistry during the last Glacial with particular focus on biomass burning emissions. Here we report high resolution (approximately annual) and decadal-scale measurements of water stable isotopic ratios, refractory black carbon concentration and particle size, semi-quantitative insoluble particle mass concentration, as well as ammonium, sea-salt sodium and non-sea-salt calcium concentrations measured from 2100 to 2365 meter (m) depth in the GISP2 core. These data ,as well as a modified simple atmospheric transport model, were used initially to evaluate aerosol emissions, transport, and deposition during rapid climate change events GI 5 through GI 12 (Liu et al., 2024).
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- Award ID(s):
- 2102917
- PAR ID:
- 10644604
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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