In situ measurements of midlatitude ClO in winter

Journal Article · Tue Jan 01 04:00:00 EST 1991 · Geophysical Research Letters (American Geophysical Union); (USA)

DOI:https://doi.org/10.1029/90GL02673· OSTI ID:5548916

Toohey, D W; Anderson, J G ^[1]; Brune, W H ^[2]; Chan, K R ^[3]

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1. Harvard Univ., Cambridge, MA (USA)
2. Pennsylvania State Univ., University Park (USA)
3. NASA Ames Research Center, Moffett Field, CA (USA)

In situ measurements of ClO in the winter lower stratosphere are presented for six flights of the NASA ER-2 aircraft from 38{degree}N to 61{degree}N. Enhanced abundances, increasing in severity with data, were observed below 20 km, where HCl and ClONO{sub 2} dominate the inorganic chlorine budget. The greatest mixing ratios, over 150 pptv, were encountered on February 20 and 21, 1989, as the vortex experienced a major warming. Although the timing of these ClO enhancements and the evidence that vortex air can reach midlatitudes, the enhancements observed early in the winter could have been caused by unknown chemistry occurring outside the vortex. In either case, photochemical loss of ozone due to catalytic reactions involving ClO at these mixing ratios may be responsible in part for the ozone decreases observed at high latitudes in the northern hemisphere.

• OSTI ID: 5548916
• Journal Information: Geophysical Research Letters (American Geophysical Union); (USA), Journal Name: Geophysical Research Letters (American Geophysical Union); (USA) Vol. 18:1; ISSN GPRLA; ISSN 0094-8276
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AIRCRAFT
ATMOSPHERIC CHEMISTRY
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
CHLORINE COMPOUNDS
CHLORINE NITRATES
CHLORINE OXIDES
EARTH ATMOSPHERE
ECOLOGICAL CONCENTRATION
HALOGEN COMPOUNDS
HYDROCHLORIC ACID
HYDROGEN COMPOUNDS
INORGANIC ACIDS
NITRATES
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
OZONE
PHOTOCHEMICAL REACTIONS
SEASONAL VARIATIONS
STRATOSPHERE
VARIATIONS
VORTICES