In Situ Measurements of Long-Lived Trace Gases in the Lower Stratosphere by Gas Chromatography

P. A. Romashkin, D. F. Hurst, James W. Elkins, G. S. Dutton, D. W. Fahey, Rick Dunn, F. L. Moore, R. C. Myers, B. D. Hall

Journal of Atmospheric and Oceanic Technology · 2001 · 54 citations · 16 references

Concepts

Abstract

Detailed information on the four-channel Airborne Chromatograph for Atmospheric Trace Species (ACATS-IV), used to measure long-lived atmospheric trace gases, is presented. Since ACATS-IV was last described in the literature, the temporal resolution of some measurements was tripled during 1997–99, chromatography was significantly changed, and data processing improved. ACATS-IV presently measures CCl3F [chlorofluorocarbon (CFC)-11], CCl2FCClF2 (CFC-113), CH3CCl3 (methyl chloroform), CCl4 (carbon tetrachloride), CH4 (methane), H2 (hydrogen), and CHCl3 (chloroform) every 140 s, and N2O (nitrous oxide), CCl2F2 (CFC-12), CBrClF2 (halon-1211), and SF6 (sulfur hexafluoride) every 70 s. An in-depth description of the instrument operation, standardization, calibration, and data processing is provided, along with a discussion of precision and uncertainties of ambient air measurements for several airborne missions.

References

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