Published In

Journal of Geophysical Research

Document Type

Article

Publication Date

6-1-1992

Subjects

Air -- Pollution -- Measurement, Air -- Pollution -- Oregon, Hydroxyl group

Abstract

Ambient HO measurements by low-pressure laser-excited fluorescence with chemical modulation, and supporting ozone and water-vapor data, are presented for periods in May and August 1987. The observed peak daytime ambient HO concentrations in Oregon are in the range (2.5 to 8) times106 molecules cm⁻³ and show small negative offsets due to photochemical interference. Direct measurements of the interference at fixed [O₃] give the dependence on ambient [H₂O] and on the modulating reagent [isobutane]. At ambient [O₃]=30 p.p.b. and 10 torr H₂O, with excitation and detection at a total pressure of 4 torr, the net interference is equal to [HO]=-1.3times10⁶ molecule cm⁻³.

Description

Copyright 1992 by the American Geophysical Union

DOI

10.1029/91JD01664

Persistent Identifier

http://archives.pdx.edu/ds/psu/7633

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