HR: 1340h
AN: A33C-1404    [Abstracts]
TI: Regional Air Quality Studies Using MOPITT CO Data : A Case Study of Linfen City and the Wei River Valley in China
AU: * Kar, J
EM: jkar@atmosp.physics.utoronto.ca
AF: University of Toronto, 60 St. George Street, Toronto, ON M5S 1A7, Canada
AU: Jones, D B
EM: dbj@atmosp.physics.utoronto.ca
AF: University of Toronto, 60 St. George Street, Toronto, ON M5S 1A7, Canada
AU: Drummond, J R
EM: james.drummond@utoronto.ca
AF: University of Toronto, 60 St. George Street, Toronto, ON M5S 1A7, Canada
AU: Zou, J
EM: jzou@atmosp.physics.utoronto.ca
AF: University of Toronto, 60 St. George Street, Toronto, ON M5S 1A7, Canada
AU: Liu, J
EM: jliu@atmosp.physics.utoronto.ca
AF: University of Toronto, 60 St. George Street, Toronto, ON M5S 1A7, Canada
AU: Nichitiu, F
EM: nichitiu@atmosp.physics.utoronto.ca
AF: University of Toronto, 60 St. George Street, Toronto, ON M5S 1A7, Canada
AB: MOPITT measures atmospheric CO using thermal channel at 4.7 μm and as such is mostly sensitive to the middle and the upper troposphere. However a recent assessment of the MOPITT averaging kernels after normalizing for non-uniform grid effects indicates that over land areas with sparse vegetation during daytime, MOPITT may have sensitivity to CO in the boundary layer. Thus it may be possible to use the MOPITT data for regional air quality studies. In particular, China with its strong emission sources and varying topography makes for an interesting area to test this. We present a case study over the Wei river valley in northern China. Linfen, ranked consistently as one of the most polluted cities globally, is located on the east bank of Fen river north east of the Wei river valley. We find that a strong CO plume associated with Linfen is clearly delineated in monthly average maps of CO mixing ratio at 850 hPa for all months when data are available. High CO mixing ratios often exceeding 300 ppbv at 850 hPa are observed near Linfen and are likely resulting from the coal based industries in the city. Further, regionally enhanced CO aligned with the Wei river valley suggests topographic effects. These features seen in MOPITT CO data are correlated with corresponding signatures of Linfen city and the Wei river valley in SCIAMACHY NO₂ tropospheric column data, which indicates that MOPITT low altitude retrievals are capturing the source regions. Seasonal variation of CO and NO₂ around Linfen city, as seen in the satellite data will be discussed. The topographic signature along the Wei river valley can also be seen in other datasets like Aura OMI NO₂ tropospheric column and MODIS aerosol optical depth.
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0365 Troposphere: composition and chemistry
DE: 0368 Troposphere: constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting