HR: 17:48h
AN: A14A-09    [Abstracts]
TI: Mobile IR- and UV-Spectroscopic Measurements of CO, SO$_{2}$ and VOC in Megacities
AU: * Samuelsson, J
EM: jerker.samuelsson@rss.chalmers.se
AF: Chalmers University of Technology, Department of Radio and Space Science, Gothenburg, SE 41296 Sweden
AU: Mellqvist, J
AF: Chalmers University of Technology, Department of Radio and Space Science, Gothenburg, SE 41296 Sweden
AU: Galle, B
AF: Chalmers University of Technology, Department of Radio and Space Science, Gothenburg, SE 41296 Sweden
AU: de Foy, B
AF: Massachusetts Institute of Technology, Department of Earth, Atmospheric and Planetary Sciences 77 Massachusetts Av., Cambridge, MA 02139 United States
AU: Garcia, A
AF: Massachusetts Institute of Technology, Department of Earth, Atmospheric and Planetary Sciences 77 Massachusetts Av., Cambridge, MA 02139 United States
AU: Molina, L T
AF: Massachusetts Institute of Technology, Department of Earth, Atmospheric and Planetary Sciences 77 Massachusetts Av., Cambridge, MA 02139 United States
AU: Molina, M J
AF: Massachusetts Institute of Technology, Department of Earth, Atmospheric and Planetary Sciences 77 Massachusetts Av., Cambridge, MA 02139 United States
AU: Volkamer, R
AF: Massachusetts Institute of Technology, Department of Earth, Atmospheric and Planetary Sciences 77 Massachusetts Av., Cambridge, MA 02139 United States
AU: Flores, E
AF: Universidad Nacional Autonoma de Mexico, Centro de Ciencias de la Atmsfera - UNAM Circuito Exterior s/n, Ciudad Universitaria Delegacion Coyoacan, Mexico D.F, 04510 Mexico
AU: Grutter, M
AF: Universidad Nacional Autonoma de Mexico, Centro de Ciencias de la Atmsfera - UNAM Circuito Exterior s/n, Ciudad Universitaria Delegacion Coyoacan, Mexico D.F, 04510 Mexico
AB: Three different types of optical instruments have been deployed at a field campaign in the Mexico City Metropolitan Area (MCMA) 2003 within three main applications: 1) Retrieval of total columns of CO at various positions within the MCMA. 2) Emission inventory of VOC (volatile organic compounds) and SO$_{2}$ from a major industrial source in Tula 100km north of the MCMA. 3) SO$_{2}$ emission inventory of the volcano Popocatepetl located nearby the MCMA. The instruments used were: a) A mobile solar FTIR (Fourier Transform InfraRed) system consisting of a fast sun tracker connected to a 0.5 cm$^{-1}$ resolution FTIR spectrometer, measuring spectra between 2 and 14 $\mu$m wavelength. b) A mobile blue sky UV (ultra violet) spectrometer measuring in the 245 to 380 nm region. c) Two open path FTIR spectrometers with 1 cm$^{-1}$ respectively 0.1 cm$^{-1}$ resolution, operating between 2-5.5 $\mu$m and 2-14 $\mu$m wavelength, respectively. The two instruments were located about 5km apart within the MCMA and measured path averaged concentrations of for instance CO, CO$_{2}$, NO, H$_{2}$CO, VOC, CH$_{4}$, N$_{2}$O over 860m and 500m path respectively. In the first application, the mobile solar FTIR measured atmospheric columns of CO at various locations within and outside the MCMA region, in order to investigate both their temporal and spatial variability. This was combined with the two fixed position long path FTIR spectrometers for studying issues like concentration heterogeneity, mixing height, horizontal advection and possibly total area CO emission. A mesoscale meteorological model (MM5) in combination with a chemical model was run by MIT (Massachusetts Institute of Technology) to generate total CO columns for comparisons. The feasibility of the method will be discussed. In the second application, emissions from a major industrial complex consisting of a powerplant, a refinery and a petrochemical industry were studied in Tula (100km north of MCMA). The solar FTIR system was used to retrieve total columns of VOC, and the mobile UV system measured total columns of SO$_{2}$. By traversing the emission plume of the industry, all the absorbing molecules in the plume cross section were integrated. Finally taking the wind speed into account the emission could be derived. Combining these emission measurements with the MM5 model and concentration measurements within the MCMA, the possible impact of this large emission source on the MCMA air quality can be studied. As a third application the mobile UV system was deployed traversing the SO$_{2}$ plume of the volcano Popocatepetl, located in close vicinity to the MCMA. At the same occasion the solar FTIR system measured HCl, SO$_{2}$ and possibly HF columns in the plume. The aim was to derive the emission of these substances from the volcano and to combine it with the MM5 model to see what the possible impact on the MCMA could be.
DE: 3359 Radiative processes
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0345 Pollution--urban and regional (0305)
DE: 0365 Troposphere--composition and chemistry
DE: 0394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting