Environ. Sci. Technol. 2004, 38, 221-228
Intercomparison of Volatile Organic Carbon Measurement Techniques and Data at La Porte during the TexAQS2000 Air Quality Study W . C . K U S T E R , * ,† B . T . J O B S O N , ‡,⊥ T. KARL,§ D. RIEMER,| E. APEL,§ P. D. GOLDAN,† AND F . C . F E H S E N F E L D †,‡ Aeronomy Laboratory, National Oceanic and Atmospheric Administration, R/AL7, 325 Broadway, Boulder, Colorado 80305, Cooperative Institute for Research in Environmental Science, University of Colorado, Boulder, Colorado 80309, Atmospheric Chemistry Division, The National Center for Atmospheric Research, Boulder, Colorado 80303, and Rosenstiel School of Marine and Atmospheric Science, Division of Marine and Atmospheric Chemistry, 4600 Rickenbacker Causeway, Miami, Florida 33149
The Texas Air Quality Study 2000 (TexAQS2000) investigated the photochemical production of ozone and the chemistry of related precursors and reaction products in the vicinity of Houston, TX. The colocation of four instruments for the measurement of volatile organic carbon compounds (VOCs) allowed a unique opportunity for the intercomparison of the different in-situ measuring techniques. The instruments included three gas chromatographs, each with a different type of detector, and a Proton-TransferReaction Mass Spectrometer (PTR-MS) with each system designed to measure a different suite of VOCs. Correlation plots and correlation statistics are presented for species measured by more than one of these instruments. The GC instruments were all in agreement to within 10-20% (slope) with coefficients of variation (r 2) of g0.85. The PTRMS agreement with other instruments was more dependent on species with some very good agreements (r2 values of ∼0.95 for some aromatics), but isoprene, acetaldehyde and propene were substantially less highly correlated (0.55
