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Updated: Jul 10, 2026
05:45
Composition and Distribution Analysis of Bioaerosols Under Different Environmental Conditions
Published on: January 7, 2019
Air-snow interactions and atmospheric chemistry
Florent Dominé1, Paul B Shepson
1CNRS, Laboratoire de Glaciologie et Géophysique de l'Environnement, B.P. 96, 54 Rue Molière, 38402 Saint Martin d'Hères cedex, France. florent@lgge.obs.ujf-grenoble.fr
Science (New York, N.Y.)
|August 31, 2002
Summary
Snow alters polar air composition, increasing atmospheric oxidation. Snowpack reactions release compounds like hydroxyl radicals (OH), affecting air quality and ice core data interpretation.
Area of Science:
- Atmospheric Chemistry
- Polar Science
- Snowpack Geochemistry
Background:
- Snow cover significantly impacts near-surface polar air composition.
- Elevated hydroxyl radical (OH) concentrations indicate enhanced atmospheric oxidative capacity.
Purpose of the Study:
- To investigate the chemical transformations occurring in snowpack and their impact on polar atmospheric composition.
- To understand the role of snow-emitted compounds in atmospheric chemistry.
Main Methods:
- Analysis of snowpack and interstitial air composition.
- Investigation of photolytic and reactive processes within snow.
- Detection of emitted species including nitrogen oxides, aldehydes, and halogens.
Main Results:
- Snow presence perturbs near-surface air, increasing OH concentrations and oxidative capacity.
- Photolysis of snow-contained nitrate ions is a key perturbation source.
- Snowpack reactions produce and release carbonyl compounds and halogens.
Conclusions:
- Snowpack chemistry significantly alters polar atmospheric composition.
- Emissions from snow affect the overlying atmosphere and interstitial air.
- Ice core analysis requires corrections for reactive species due to snowpack influence.
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