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Updated: Dec 31, 2025
10:14
Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography
Published on: May 16, 2014
12.9K
Quantitative detection of iodine in the stratosphere
Theodore K Koenig1,2, Sunil Baidar1,2, Pedro Campuzano-Jost1,2
1Department of Chemistry, University of Colorado Boulder, Boulder, CO 80309.
Summary
Stratospheric iodine is quantified for the first time, revealing its significant role in ozone depletion. Increased iodine emissions from pollution may contribute to lower stratospheric ozone levels.
Area of Science:
- Atmospheric Chemistry
- Ozone Layer Dynamics
- Halogen Geochemistry
Background:
- Oceanic iodine emissions impact tropospheric ozone and particle formation.
- Stratospheric iodine's role in ozone depletion remains uncertain due to limited measurements.
Purpose of the Study:
- To provide the first quantitative measurements of iodine species in the stratosphere.
- To assess the impact of stratospheric iodine on ozone depletion and formation of new particles.
Main Methods:
- Aircraft-based in-situ measurements of iodine monoxide radicals and particulate iodine.
- Analysis of gas-phase and particulate iodine concentrations in the upper troposphere and stratosphere.
Main Results:
- Total inorganic iodine (Iy) injection to the stratosphere is 0.77 ± 0.10 parts per trillion by volume (pptv).
- Iodine accounts for 32% of halogen-induced ozone loss, primarily through heterogeneous chemistry.
- Anthropogenic activities have tripled iodine emissions since preindustrial times, influencing stratospheric ozone levels.
Conclusions:
- Stratospheric iodine plays a significant, previously underestimated role in ozone depletion.
- Active iodine recycling on ice in the upper troposphere and multiphase chemistry in the stratosphere are key processes.
- Increasing anthropogenic iodine emissions have implications for ozone radiative forcing and particle formation.
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