Articles | Volume 4, issue 2
Atmos. Meas. Tech., 4, 245–268, 2011
Atmos. Meas. Tech., 4, 245–268, 2011

  10 Feb 2011

10 Feb 2011

Characterization and intercomparison of aerosol absorption photometers: result of two intercomparison workshops

T. Müller1, J. S. Henzing2, G. de Leeuw2,3,6, A. Wiedensohler1, A. Alastuey7, H. Angelov8, M. Bizjak9, M. Collaud Coen10, J. E. Engström11, C. Gruening12, R. Hillamo4, A. Hoffer13, K. Imre13, P. Ivanow8, G. Jennings14, J. Y. Sun15, N. Kalivitis16, H. Karlsson17, M. Komppula5, P. Laj18,19, S.-M. Li20, C. Lunder22, A. Marinoni23, S. Martins dos Santos12, M. Moerman2, A. Nowak1, J. A. Ogren24, A. Petzold25, J. M. Pichon18, S. Rodriquez26,27, S. Sharma21, P. J. Sheridan24, K. Teinilä4, T. Tuch1, M. Viana7, A. Virkkula6, E. Weingartner28, R. Wilhelm29, and Y. Q. Wang30 T. Müller et al.
  • 1Leibniz Institute for Tropospheric Research, Leipzig, Germany
  • 2Netherlands Organisation for Applied Scientific Research, TNO, 80015 Utrecht, The Netherlands
  • 3Finnish Meteorological Institute, Climate Change Unit, Helsinki, Finland
  • 4Finnish Meteorological Institute, Air Quality Research, Helsinki, Finland
  • 5Finnish Meteorological Institute, Kuopio Unit, Kuopio, Finland
  • 6University of Helsinki, Dept of Physics, Helsinki, Finland
  • 7Institute for Environmental Assessment and Water Research, Barcelona, Spain
  • 8Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Sofia, Bulgaria
  • 9University of Ljubljana, Faculty of Health Science, Ljubljana, Slovenia
  • 10MeteoSwiss, Aerological Station, Les Invuardes, 1530 Payerne, Switzerland
  • 11University of Stockholm, Department of Meteorology, Stockholm, Sweden
  • 12European Commission – DG Joint Research Centre, IES/CCU, Ispra, Italy
  • 13Department of Earth and Environmental Sciences, University of Pannonia, Pannonia, Hungary
  • 14National University of Ireland, Galway, School of Physics/Environmental Change Institute, Galway, Ireland
  • 15Key Laboratory for Atmospheric Chemistry, Center for Atmosphere Watch and Services, Chinese Academy of Meteorological Sciences, China Meteorological Administration, Beijing, 100081, China
  • 16Nikos Kalivitis, Environmental Chemical Processes Laboratory, Dept. of Chemistry, Univ. of Crete, Heraklion, Greece
  • 17Department of Applied Environmental Science, Stockholm University, Stockholm, Sweden
  • 18CNRS/LaMP Université Blaise Pascal, 24, avenue des Landais, 63177 Aubière cedex, France
  • 19Laboratoire de Glaciologie et Géophysique de l'Environnement Université Joseph Fourier, Grenoble 1/CNRS, 38400 St Martin d'Hères, France
  • 20Air Quality Research Division, Science and Technology Branch, Environment Canada, 4905 Dufferin Street, Toronto, Ontario, M3H 5T4, Canada
  • 21Climate Research Division, Science and Technology Branch, Environment Canada, 4905 Dufferin Street, Toronto, Ontario, M3H 5T4, Canada
  • 22Norwegian Institute for Air Research, Kjeller, Norway
  • 23Institute of Atmospheric Sciences and Climate, Via Gobetti 101, 40129 Bologna, Italy
  • 24NOAA Earth System Research Laboratory, Boulder, CO 80305, USA
  • 25Institute für Physik der Atmosphäre, DLR, Oberpfaffenhofen, Wessling, 82234, Germany
  • 26Izaña Atmospheric Research Center, AEMET, Associated Unit to CSIC "Studies on Atmospheric Pollution", La Marina 20, planta 6, E38071, Santa Cruz de Tenerife, Canary Islands, Spain
  • 27University of Huelva, Associated Unit to CSIC "Air Pollution", Campus El Carmen, 21071, Huelva, Spain
  • 28Laboratory of Atmospheric Chemistry, Paul Scherrer Institut, Villigen, Switzerland
  • 29German Weather Service, Meteorological Observatory Hohenpeißenberg, Dept. GAW, 82383 Hohenpeißenberg, Germany
  • 30Chinese Academy of Meteorological Sciences, Beijing, 100081, China

Abstract. Absorption photometers for real time application have been available since the 1980s, but the use of filter-based instruments to derive information on aerosol properties (absorption coefficient and black carbon, BC) is still a matter of debate. Several workshops have been conducted to investigate the performance of individual instruments over the intervening years. Two workshops with large sets of aerosol absorption photometers were conducted in 2005 and 2007. The data from these instruments were corrected using existing methods before further analysis. The inter-comparison shows a large variation between the responses to absorbing aerosol particles for different types of instruments. The unit to unit variability between instruments can be up to 30% for Particle Soot Absorption Photometers (PSAPs) and Aethalometers. Multi Angle Absorption Photometers (MAAPs) showed a variability of less than 5%. Reasons for the high variability were identified to be variations in sample flow and spot size. It was observed that different flow rates influence system performance with respect to response to absorption and instrumental noise. Measurements with non absorbing particles showed that the current corrections of a cross sensitivity to particle scattering are not sufficient. Remaining cross sensitivities were found to be a function of the total particle load on the filter. The large variation between the response to absorbing aerosol particles for different types of instruments indicates that current correction functions for absorption photometers are not adequate.