On the distribution of formaldehyde in the western Po-Valley, Italy, during FORMAT 2002/2003 W. Junkermann Karlsruhe Institut of Technology, Institute for Meteorology and Climate Research, IMK-IFU, Kreuzeckbahnstr. 19, 82467 Garmisch-Partenkirchen, Germany
Abstract. Formaldehyde was measured in the area of Milano, Italy, during the 2002 and
2003 FORMAT campaigns at three ground field sites and from an ultralight
aircraft. The horizontal distributions show a strong impact of local
emissions at a site in the centre of Milano and more photochemically driven
diurnal patterns in the remote locations north and south of the city. The
mixing ratios in the agricultural areas upwind of Milano were comparable to
those downwind indicating the importance of biogenic emissions and
anthropogenic agricultural activities. The vertical distributions were
dominated by transport processes with advection of CH2O above the
planetary boundary layer by cloud venting. Comparison to previously
published model calculations, based on part of the data set, show
discrepancies both, in the diurnal patterns and in the regional distribution
which allude to uncertainties in emission inventories.
Citation: Junkermann, W.: On the distribution of formaldehyde in the western Po-Valley, Italy, during FORMAT 2002/2003, Atmos. Chem. Phys., 9, 9187-9196, doi:10.5194/acp-9-9187-2009, 2009.