Articles | Volume 5, issue 2
Atmos. Meas. Tech., 5, 457–485, 2012

Special issue: Cabauw Intercomparison campaign for Nitrogen Dioxide measuring...

Atmos. Meas. Tech., 5, 457–485, 2012

Research article 27 Feb 2012

Research article | 27 Feb 2012

The Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI): design, execution, and early results

A. J. M. Piters1, K. F. Boersma2,1, M. Kroon1, J. C. Hains3, M. Van Roozendael4, F. Wittrock5, N. Abuhassan7,6, C. Adams8, M. Akrami8, M. A. F. Allaart1, A. Apituley10,1, S. Beirle24, J. B. Bergwerff10, A. J. C. Berkhout10, D. Brunner11, A. Cede12,7, J. Chong13, K. Clémer4, C. Fayt4, U. Frieß14, L. F. L. Gast10, M. Gil-Ojeda9, F. Goutail15, R. Graves16, A. Griesfeller15, K. Großmann14, G. Hemerijckx4, F. Hendrick4, B. Henzing17, J. Herman12,7, C. Hermans4, M. Hoexum10, G. R. van der Hoff10, H. Irie18, P. V. Johnston19, Y. Kanaya18, Y. J. Kim13, H. Klein Baltink1, K. Kreher19, G. de Leeuw20,17,27, R. Leigh16, A. Merlaud4, M. M. Moerman17, P. S. Monks16, G. H. Mount21, M. Navarro-Comas9, H. Oetjen22, A. Pazmino15, M. Perez-Camacho9, E. Peters5, A. du Piesanie1, G. Pinardi4, O. Puentedura9, A. Richter5, H. K. Roscoe23, A. Schönhardt5, B. Schwarzenbach11, R. Shaiganfar24, W. Sluis1, E. Spinei21, A. P. Stolk10, K. Strong8, D. P. J. Swart10, H. Takashima18, T. Vlemmix1, M. Vrekoussis5,26, T. Wagner24, C. Whyte8, K. M. Wilson10,1, M. Yela9, S. Yilmaz14, P. Zieger25, and Y. Zhou11 A. J. M. Piters et al.
  • 1Royal Netherlands Meteorological Institute (KNMI), De Bilt, The Netherlands
  • 2Technical University Eindhoven (TUE), Eindhoven, The Netherlands
  • 3Maryland Department of the Environment (MDE), Baltimore, MD, USA
  • 4Belgian Institute for Space Aeronomy (BIRA-IASB), Brussels, Belgium
  • 5Institute of Environmental Physics (IUP), University of Bremen, Bremen, Germany
  • 6Morgan State University (MSU), Baltimore, MD, USA
  • 7NASA/Goddard Space Flight Center (GSFC), Greenbelt, MD, USA
  • 8Department of Physics, University of Toronto, Toronto, Ontario, Canada
  • 9National Institute for Aerospace technology (INTA), Madrid, Spain
  • 10National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
  • 11Swiss Federal Laboratories for Materials Science and Technology (EMPA), Dübendorff, Switzerland
  • 12University of Maryland, Baltimore County (UMBC), Catonsville, MD, USA
  • 13Gwangju Institute of Science and Technology, Gwangiu, Republic of Korea
  • 14Institute of Environmental Physics, University of Heidelberg, Heidelberg, Germany
  • 15Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Guyancourt, France
  • 16Department of Chemistry, University of Leicester, Leicester, UK
  • 17Netherlands Organization for Applied Scientific Research (TNO), Utrecht, The Netherlands
  • 18Research Institute for Global Change, JAMSTEC, Yokohama, Japan
  • 19National Institute of Water & Atmospheric Research (NIWA), Lauder, New Zealand
  • 20Finnish Meteorological Institute (FMI), Helsinki, Finland
  • 21Laboratory for Atmospheric Research, Washington State University (WSU), Pullman, WA, USA
  • 22School of Chemistry, University of Leeds, Leeds, UK
  • 23British Antarctic Survey (BAS), Cambridge, UK
  • 24Max Planck Institute for Chemistry (MPIC), Mainz, Germany
  • 25Laboratory of Atmospheric Chemistry, Paul Scherrer Institut (PSI), Villigen, Switzerland
  • 26Research Center for Atmospheric Physics and Climatology, Academy of Athens, Athens, Greece
  • 27Department of Physics, University of Helsinki, Helsinki, Finland

Abstract. From June to July 2009 more than thirty different in-situ and remote sensing instruments from all over the world participated in the Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI). The campaign took place at KNMI's Cabauw Experimental Site for Atmospheric Research (CESAR) in the Netherlands. Its main objectives were to determine the accuracy of state-of-the-art ground-based measurement techniques for the detection of atmospheric nitrogen dioxide (both in-situ and remote sensing), and to investigate their usability in satellite data validation. The expected outcomes are recommendations regarding the operation and calibration of such instruments, retrieval settings, and observation strategies for the use in ground-based networks for air quality monitoring and satellite data validation. Twenty-four optical spectrometers participated in the campaign, of which twenty-one had the capability to scan different elevation angles consecutively, the so-called Multi-axis DOAS systems, thereby collecting vertical profile information, in particular for nitrogen dioxide and aerosol. Various in-situ samplers and lidar instruments simultaneously characterized the variability of atmospheric trace gases and the physical properties of aerosol particles. A large data set of continuous measurements of these atmospheric constituents has been collected under various meteorological conditions and air pollution levels. Together with the permanent measurement capability at the CESAR site characterizing the meteorological state of the atmosphere, the CINDI campaign provided a comprehensive observational data set of atmospheric constituents in a highly polluted region of the world during summertime. First detailed comparisons performed with the CINDI data show that slant column measurements of NO2, O4 and HCHO with MAX-DOAS agree within 5 to 15%, vertical profiles of NO2 derived from several independent instruments agree within 25% of one another, and MAX-DOAS aerosol optical thickness agrees within 20–30% with AERONET data. For the in-situ NO2 instrument using a molybdenum converter, a bias was found as large as 5 ppbv during day time, when compared to the other in-situ instruments using photolytic converters.