Inferring the abundances of ClO and HO sub 2 from Spacelab 3 atmospheric trace molecule spectroscopy observations

Journal Article · Wed Feb 20 04:00:00 EST 1991 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/90JD02369· OSTI ID:5400781

Allen, M; Delitsky, M L ^[1]

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1. California Inst. of Tech., Pasadena (USA)

The vertical distributions of the important highly reactive stratospheric species, ClO and HO{sub 2}, have been inferred from Spacelab 3 (May 1985) Atmospheric Trace Molecule Spectroscopy (ATMOS) measurements of more detectable radical and reservoir species. A simple steady state algebraic expression for ClO, utilizing the observed ClONO{sub 2}/NO{sub 2} abundance ratio, approximates the ClO results of a time-dependent photochemical model at sunset (30{degree}N). Balloon measurements of ClO and comparisons of time-dependent photochemical model calculations of ClONO{sub 2} and HCl with the corresponding ATMOS profiles suggest that the actual ClO values are less than the time-dependent model profiles for ClO at sunset and sunrise (47{degree}S). Errors in the current model simulation of the partitioning among the principal free chlorine species (HCl, ClONO{sub 2}, and ClO) are indicated. However, a comparison of model results with observations of HOCl suggests that the calculated ClO abundance is not a significant overestimate of actual values. A similar methodology is applied to inferring the HO{sub 2} distribution, either algebraically using the ATMOS-measured HO{sub 2}NO{sub 2}/NO{sub 2} abundance ratio or numerically utilizing the time-dependent model. The algebraic results agree with the time-dependent model values to better than a factor of 2 at sunrise. The accuracy of the time-dependent model calculations of HO{sub 2} is suggested by the agreement between model results and ATMOS observations for HO{sub 2}NO{sub 2} and balloon measurements of HO{sub 2}. This confirms for the first time the procedure suggested previously by a number of authors of deriving HO{sub x} abundances from observed fields of O{sub 3} and H{sub 2}O.

• OSTI ID: 5400781
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 96:D2; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AIRSHIPS
ATMOSPHERIC CHEMISTRY
BALLOONS
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
CHLORINE COMPOUNDS
CHLORINE NITRATES
CHLORINE OXIDES
CLIMATE MODELS
COMPARATIVE EVALUATIONS
DISTRIBUTION
EARTH ATMOSPHERE
ECOLOGICAL CONCENTRATION
HALOGEN COMPOUNDS
HYDROCHLORIC ACID
HYDROGEN COMPOUNDS
HYDROPEROXY RADICALS
INORGANIC ACIDS
MATHEMATICAL MODELS
NITRATES
NITROGEN COMPOUNDS
NITROGEN OXIDES
OXIDES
OXYGEN COMPOUNDS
OZONE
PHOTOCHEMICAL REACTIONS
RADICALS
SPACE VEHICLES
SPECTROSCOPY
STRATOSPHERE
TIME DEPENDENCE
VEHICLES