The impact of MM5 and WRF meteorology over complex terrain on CHIMERE model calculations 1European Commission – DG Joint Research Centre, Institute for Environment and Sustainability, 21020 Ispra, Italy
2INERIS, Institut National de l'Environnement industriel et des Risques, Parc Technologique ALATA, 60550 Verneuil-en-Halatte, France
3Laboratoire de Météorologie Dynamique, Institut Pierre-Simon Laplace, Ecole Polytechnique, Palaiseau, France
4Department of Applied Physics, Eindhoven University of Technology, Eindhoven, The Netherlands
*now at: Energy, Environment and Water Research Centre, The Cyprus Institute, 20 Kavafi Street, 1645, Nicosia, Cyprus
Received: 17 Nov 2008 – Published in Atmos. Chem. Phys. Discuss.: 26 Jan 2009 – Published: 11 Sep 2009Abstract. The objective of this study is to evaluate the impact of meteorological
input data on calculated gas and aerosol concentrations. We use two
different meteorological models (MM5 and WRF) together with the chemistry
transport model CHIMERE. We focus on the Po valley area (Italy) for January
and June 2005.
Firstly we evaluate the meteorological parameters with observations. The
analysis shows that the performance of both models in calculating surface
parameters is similar, however differences are still observed.
Secondly, we analyze the impact of using MM5 and WRF on calculated PM10 and
O3 concentrations. In general CHIMERE/MM5 and CHIMERE/WRF underestimate
the PMv concentrations for January. The difference in PM10 concentrations
for January between CHIMERE/MM5 and CHIMERE/WRF is around a factor 1.6 (PM10
higher for CHIMERE/MM5). This difference and the larger underestimation in
PM10 concentrations by CHIMERE/WRF are related to the differences in heat
fluxes and the resulting PBL heights calculated by WRF. In general the PBL
height by WRF meteorology is a factor 2.8 higher at noon in January than
calculated by MM5. This study showed that the difference in microphysics
scheme has an impact on the profile of cloud liquid water (CLW) calculated
by the meteorological driver and therefore on the production of SO4
A sensitivity analysis shows that changing the Noah Land Surface Model (LSM)
in our WRF pre-processing for the 5-layer soil temperature model,
calculated monthly mean PMv concentrations increase by 30%, due to the
change in the heat fluxes and the resulting PBL heights.
For June, PM10 calculated concentrations by CHIMERE/MM5 and CHIMERE/WRF are
similar and agree with the observations. Calculated O3 values for June
are in general overestimated by a factor 1.3 by CHIMERE/MM5 and CHIMERE/WRF.
High temporal correlations are found between modeled and observed O3
Citation: de Meij, A., Gzella, A., Cuvelier, C., Thunis, P., Bessagnet, B., Vinuesa, J. F., Menut, L., and Kelder, H. M.: The impact of MM5 and WRF meteorology over complex terrain on CHIMERE model calculations, Atmos. Chem. Phys., 9, 6611-6632, doi:10.5194/acp-9-6611-2009, 2009.