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USGS · 70036071

A 50-year record of NOx and SO2 sources in precipitation in the Northern Rocky Mountains, USA

David L. Naftz·Paul F. Schuster·Craig A. Johnson
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Abstract

Ice-core samples from Upper Fremont Glacier (UFG), Wyoming, were used as proxy records for the chemical composition of atmospheric deposition. Results of analysis of the ice-core samples for stable isotopes of nitrogen (δ 15 N, ) and sulfur (δ 34 S, ), as well as and deposition rates from the late-1940s thru the early-1990s, were used to enhance and extend existing National Atmospheric Deposition Program/National Trends Network (NADP/NTN) data in western Wyoming. The most enriched δ 34 S value in the UFG ice-core samples coincided with snow deposited during the 1980 eruption of Mt. St. Helens, Washington. The remaining δ 34 S values were similar to the isotopic composition of coal from southern Wyoming. The δ 15 N values in ice-core samples representing a similar period of snow deposition were negative, ranging from -5.9 to -3.2 ‰ and all fall within the δ 15 N values expected from vehicle emissions. Ice-core nitrate and sulfate deposition data reflect the sharply increasing U.S. emissions data from 1950 to the mid-1970s.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 42.72683914955442° to 43.18515250937298° latitude; -109.97314453125° to -109.3414306640625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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David L. Naftz, Paul F. Schuster, Craig A. Johnson. 2011-03-07. A 50-year record of NOx and SO2 sources in precipitation in the Northern Rocky Mountains, USA. https://doi.org/10.1186/1467-4866-12-4

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