Read Full Article    Cited by

GEOPHYSICAL RESEARCH LETTERS, VOL. 23, NO. 22, PAGES 3215–3218, 1996

Monitoring Potential Photochemical Interference in Laser-Induced Fluorescence Measurements of Atmospheric OH

Manvendra K. Dubey

Department of Chemistry, Harvard University, Cambridge, MA

Thomas F. Hanisco

Department of Chemistry, Harvard University, Cambridge, MA

Paul O. Wennberg

Department of Chemistry, Harvard University, Cambridge, MA

James G. Anderson

Department of Chemistry, Harvard University, Cambridge, MA

Abstract

In situ laser-induced fluorescence measurements of atmospheric OH are susceptible to interference from laser generated OH, particularly in the troposphere. To quantify this interference we implement the addition of perfluoropropene, C₃F₆, for the chemical removal of OH from the ambient air. The removal rate of OH by C₃F₆ is determined in the laboratory using the discharge flow technique. Over the temperature range 249 to 296 K the rate constant is (6.0 ± 0.8) × 10⁻¹³ exp[(370 ± 40)/T] cm³ molecule⁻¹ s⁻¹, independent of pressure. In situ measurements using C₃F₆ addition are performed in both aircraft-borne and ground-based experiments. These studies show that laser excitation of the ²Σ⁺(v=1)←²Π(v=0) transition (282 nm) at high pulse repetition rates and low peak power can provide reliable and sensitive measurements of tropospheric OH.

Received 17 July 1996; accepted 19 September 1996.

Read Full Article    Cited by

Citation: Dubey, M. K., T. F. Hanisco, P. O. Wennberg, and J. G. Anderson (1996), Monitoring Potential Photochemical Interference in Laser-Induced Fluorescence Measurements of Atmospheric OH, Geophys. Res. Lett., 23(22), 3215–3218.

Copyright 1996 by the American Geophysical Union.