Articles | Volume 5, issue 6
Geosci. Model Dev., 5, 1323–1339, 2012
Geosci. Model Dev., 5, 1323–1339, 2012

Model description paper 01 Nov 2012

Model description paper | 01 Nov 2012

The regional aerosol-climate model REMO-HAM

J.-P. Pietikäinen1,2,3, D. O'Donnell1, C. Teichmann2,3, U. Karstens4, S. Pfeifer3, J. Kazil6,5, R. Podzun†,2,3, S. Fiedler7, H. Kokkola1, W. Birmili8, C. O'Dowd9, U. Baltensperger10, E. Weingartner10, R. Gehrig11, G. Spindler7, M. Kulmala12, J. Feichter2, D. Jacob2,3, and A. Laaksonen13,1 J.-P. Pietikäinen et al.
  • 1Finnish Meteorological Institute, P.O. Box 503, 00101 Helsinki, Finland
  • 2Max Planck Institute for Meteorology, Bundesstrasse 53, 20146 Hamburg, Germany
  • 3Climate Service Center, Chilehaus – Eingang B, Fischertwiete 1, 20095 Hamburg, Germany
  • 4Max Planck Institute for Biogeochemistry, Hans-Knöll-Straße 10, 07745 Jena, Germany
  • 5Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado, 325 Broadway R/CSD, Boulder, Colorado, USA
  • 6NOAA Earth System Research Laboratory (ESRL), 325 Broadway CO 80305-3337, Boulder, Colorado, USA
  • 7Institute for Climate and Atmospheric Science, University of Leeds, LS2 9JT, Leeds, UK
  • 8Leibniz Institute for Tropospheric Research (IfT), Permoserstr. 15, 04318 Leipzig, Germany
  • 9National University of Ireland Galway, University Road, Galway, Ireland
  • 10Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
  • 11Empa – Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
  • 12Department of Physics, University of Helsinki, P.O. Box 44, 00014 Helsinki, Finland
  • 13Department of Applied Physics, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
  • Deceased in September 2011

Abstract. REMO-HAM is a new regional aerosol-climate model. It is based on the REMO regional climate model and includes most of the major aerosol processes. The structure for aerosol is similar to the global aerosol-climate model ECHAM5-HAM, for example the aerosol module HAM is coupled with a two-moment stratiform cloud scheme. On the other hand, REMO-HAM does not include an online coupled aerosol-radiation nor a secondary organic aerosol module. In this work, we evaluate the model and compare the results against ECHAM5-HAM and measurements. Four different measurement sites were chosen for the comparison of total number concentrations, size distributions and gas phase sulfur dioxide concentrations: Hyytiälä in Finland, Melpitz in Germany, Mace Head in Ireland and Jungfraujoch in Switzerland. REMO-HAM is run with two different resolutions: 50 × 50 km2 and 10 × 10 km2. Based on our simulations, REMO-HAM is in reasonable agreement with the measured values. The differences in the total number concentrations between REMO-HAM and ECHAM5-HAM can be mainly explained by the difference in the nucleation mode. Since we did not use activation nor kinetic nucleation for the boundary layer, the total number concentrations are somewhat underestimated. From the meteorological point of view, REMO-HAM represents the precipitation fields and 2 m temperature profile very well compared to measurement. Overall, we show that REMO-HAM is a functional aerosol-climate model, which will be used in further studies.