Aerosol extinction profiles at 525 nm and 1020 nm derived from ACE imager data: comparisons with GOMOS, SAGE II, SAGE III, POAM III, and OSIRIS F. Vanhellemont1, C. Tetard2, A. Bourassa3, M. Fromm4, J. Dodion1, D. Fussen1, C. Brogniez2, D. Degenstein3, K. L. Gilbert5, D. N. Turnbull5, P. Bernath5,6, C. Boone5, and K. A. Walker5,7 1Belgian Institute for Space Aeronomy, Ringlaan 3, B-1180, Brussels, Belgium 2LOA, Université de Science et Technologies de Lille, Bâtiment P5, F-59655 Villeneuve d'Ascq Cedex, France 3University of Saskatchewan, 116 Science Place, Saskatoon, SK S7N 5E2, Canada 4Naval Research Lab, 4555 Overlook Ave. SW, Washington, DC 20375, USA 5Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada 6Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK 7Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario, M5S 1A7, Canada
Abstract. The Canadian ACE (Atmospheric Chemistry Experiment) mission is dedicated to the retrieval of a
large number of atmospheric trace gas species using the solar occultation technique in the
infrared and UV/visible spectral domain. However, two additional solar disk imagers (at 525 nm
and 1020 nm) were added for a number of reasons, including the retrieval of aerosol and cloud
products. In this paper, we present first comparison results for these imager aerosol/cloud
optical extinction coefficient profiles, with the ones derived from measurements performed
by 3 solar occultation instruments (SAGE II, SAGE III, POAM III), one stellar
occultation instrument (GOMOS) and one limb sounder (OSIRIS). The results indicate that the ACE imager
profiles are of good quality in the upper troposphere/lower stratosphere, although the aerosol extinction
for the visible channel at 525 nm contains a significant negative bias at higher altitudes, while the relative
differences indicate that ACE profiles are almost always too high at 1020 nm. Both problems are probably related
to ACE imager instrumental issues.
Citation: Vanhellemont, F., Tetard, C., Bourassa, A., Fromm, M., Dodion, J., Fussen, D., Brogniez, C., Degenstein, D., Gilbert, K. L., Turnbull, D. N., Bernath, P., Boone, C., and Walker, K. A.: Aerosol extinction profiles at 525 nm and 1020 nm derived from ACE imager data: comparisons with GOMOS, SAGE II, SAGE III, POAM III, and OSIRIS, Atmos. Chem. Phys., 8, 2027-2037, doi:10.5194/acp-8-2027-2008, 2008.