Field Studies in Atmospheric Chemistry

P. H. Daum
Atmospheric Sciences Division
Environmental Sciences Department
Brookhaven National Laboratory
P.O. Box 5000, Building 815E
Upton, NY 11973-5000
631-344-7283
fax 631-344-2887
phdaum@bnl.gov

L. I. Kleinman
Brookhaven National Laboratory

Field campaigns and analysis activities are conducted to obtain a process level understanding of the formation of atmospheric oxidants and aerosols in diverse chemical and meteorological environments. Campaigns typically incorporate both aircraft and surface based measurements of trace gases, aerosols, and meteorological variables. Species that are measured include primary species such as carbon monoxide, oxides of nitrogen, and light hydrocarbons and product species such as ozone, aldehydes, peroxides, nitrates and aerosols. The relationship between the concentrations of these species, in the context of their spatial and temporal distribution, is used to identify and quantify the importance of potential pathways for the chemical production of ozone and aerosols in the atmosphere. Such information is used to test and refine the numerical models needed to understand the formation of aerosols, ozone, other photochemical oxidants, and to evaluate alternate strategies for the management of these pollutants. This work is conducted independently and in conjunction with the Southern Oxidants Study (SOS), the North American Research Strategy for Tropospheric Ozone (NARSTO) program, and various state and local governments. Our most recent, major study (TexAQS 2000) was conducted in Houston, Texas during the late summer of 2000. Analysis of the data is showing that ozone production in Houston is greatly influenced by emissions of hydrocarbons from the Houston Ship Channel, a heavily industrialized region that extends from Galveston Bay virtually into the center of Houston. Ozone in this region is observed to form at an extremely rapid rate (100 ppb/h), at very high efficiency, and to produce localized O3 plumes that exhibit peak concentrations on the order of 250 ppb. Analysis of the chemical and meteorological characteristics of ozone formation is Houston is continuing.

Some preliminary results from the Houston study can be found in the viewgraphs presented at a recent meeting of TexAQS 2000 participants. More recent information regarding TexAQS 2000 can be found in the viewgraphs from a presentation at the Atmospheric Sciences Program Annual Meeting held in March 2002.