Interference Testing for Atmospheric HO_x Measurements by Laser-induced Fluorescence

Authors: Ren X.¹; Harder H.²; Martinez M.²; Faloona I.C.³; Tan D.⁴; Lesher R.L.⁵; Di Carlo P.⁶; Simpas J.B.⁵; Brune W.H.⁵

Source: Journal of Atmospheric Chemistry, Volume 47, Number 2, February 2004 , pp. 169-190(22)

Publisher: Springer

Buy & download fulltext article:

Price: $47.00 plus tax (Refund Policy)

Abstract:

Accurate OH and HO₂ (collectively called HO_x) measurements by laser-induced fluorescence (LIF) may be contaminated by spurious signals from interfering atmospheric chemicals or from the instrument itself. Interference tests must be conducted to ensure that observed OH signal originates solely from ambient OH and is not due to instrument artifacts. Several tests were performed on the Penn State LIF HO_x instrument, both in the laboratory and in the field. These included measurements of the instrument's zero signal by using either zero air or perfluoropropylene to remove OH, examination of spectral interferences from naphthalene, sulfur dioxide, and formaldehyde, and tests of interferences by addition of suspected interfering atmospheric chemicals, including ozone, hydrogen peroxide, nitrous acid, formaldehyde, nitric acid, acetone, and organic peroxy radicals (RO₂). All tests lacked evidence of significant interferences for measurements in the atmosphere, including highly polluted urban environments.

Keywords: HOx measurements; interference; laser-induced fluorescence; nighttime OH

Document Type: Research article

DOI: http://dx.doi.org/10.1023/B:JOCH.0000021037.46866.81

Affiliations: 1: Department of Meteorology, Pennsylvania State University, 503 Walker Building, University Park, PA 16802, U.S.A., ren@essc.psu.edu, Email: ren@essc.psu.edu 2: Department of Meteorology, Pennsylvania State University, 503 Walker Building, University Park, PA 16802, U.S.A.; Now at Max-Planck-Institut für Chemie, D-55116 Mainz, Germany 3: Department of Meteorology, Pennsylvania State University, 503 Walker Building, University Park, PA 16802, U.S.A.; Now at Department of Land, Air and Water Resources, University of California at Davis, Davis, CA, U.S.A. 4: Department of Meteorology, Pennsylvania State University, 503 Walker Building, University Park, PA 16802, U.S.A.; Now at School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, U.S.A. 5: Department of Meteorology, Pennsylvania State University, 503 Walker Building, University Park, PA 16802, U.S.A. 6: Department of Meteorology, Pennsylvania State University, 503 Walker Building, University Park, PA 16802, U.S.A.; CETEMPS-Dipartimento di Fisica, Università degli Studi di L'Aquila, Via Vetoio, Coppito, Italy