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Isotopic composition of Antarctic Dry Valley nitrate: Implications for NOy sources and cycling in Antarctica

G. Michalski·James G. Bockheim·C. Kendall·M. Thiemens
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Abstract

Nitrates minerals from the Dry Valleys of Antarctica have been analyzed for their oxygen and nitrogen isotopic compositions. The 15 N was depleted with δ 15 N values ranging from −9.5 to −26.2‰, whereas the 17 O and 18 O isotopes were highly enriched (with excess 17 O) with δ 18 O values spanning 62–76‰ and Δ 17 O values from 28.9 to 32.7‰. These are the largest 17 O enrichments observed in any known mineral. The oxygen isotopes indicate that nitrate is from a combination of tropospheric transport of photochemically produced HNO 3 and HNO 3 formed in the stratosphere.

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G. Michalski, James G. Bockheim, C. Kendall, M. Thiemens. 2005-07-09. Isotopic composition of Antarctic Dry Valley nitrate: Implications for NOy sources and cycling in Antarctica. https://doi.org/10.1029/2004gl022121

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