Effects of postdepositional processing on nitrogen isotopes of nitrate in the Greenland Ice Sheet Project 2 ice core. Issue 13 (7th July 2015)

• Record Type: Journal Article
• Authors: Geng, Lei; Zatko, Maria C.; Alexander, Becky; Fudge, T. J.; Schauer, Andrew J.; Murray, Lee T.; Mickley, Loretta J.
• Is Part Of: Geophysical research letters. Volume 42:Issue 13(2015:Jul.)
• Page Start: 5346
• Page End: 5354
• Publication Date: 2015-07-07
• Subjects: Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2015GL064218
• Languages: English
• ISSNs: 0094-8276

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>Records of ice core nitrate and its isotopes hold the potential to assess past atmospheric conditions regarding NO<italic>_x</italic> and oxidant levels. However, relating such records to past atmospheric conditions requires a site‐specific understanding of the postdepositional processing of snow nitrate. We report δ¹⁵N(NO₃⁻) records from the Greenland Ice Sheet Project 2 (GISP2) ice core over major climate transitions. Model calculations and comparison with records of parameters influencing UV‐driven postdepositional processing of snow nitrate suggest that the observed variability in GISP2 δ¹⁵N(NO₃⁻) over major climate transitions is primarily driven by changes in the degree of postdepositional loss of snow nitrate. Estimates of the fractional loss of snow nitrate is (16–23)% in the Holocene and (45–53)% in the glacial period, suggesting a (41 ± 32)% lower nitrate depositional flux to Greenland during the glacial period relative to the Holocene.</p> </abstract>