Evaluation of the parametrized transport of lead-210 in high-altitude European sites
I. Dombrowski-Etchevers1, V.-H. Peuch1, B. Josse1, and M. Legrand21CNRM/GAME, Météo-France/CNRS, Toulouse and Grenoble, France 2Laboratoire de Glaciologie et de Geophysique de l'Environnement, CNRS, Saint-Martin d'Heres, France
Received: 26 Jan 2009 – Accepted for review: 04 Feb 2009 – Discussion started: 11 Mar 2009
Abstract. One important aspect in current climate modelling is to correctly simulate the regional variability of aerosols forcings. A first step to address this issue is to evaluate the tropospheric vertical distribution of submicronic aerosol (including sulfate and organic aerosol) in particular in the free troposphere.
210Pb is particularly interesting to study the dynamic transport by chemistry and transport models, because it is an excellent passive tracer of atmospheric circulation. Hence, it is a simple representative of atmospheric submicronic aerosol and its transport is well correlated with sulfate aerosol. Indeed, 210Pb and 222Rn (its radioactive parent) have been widely used for model verification. We present here pluriannual simulations of 210Pb made with the multiscale global to regional model MOCAGE of Météo-France, which allows to investigate resolution effects over Europe and specially anomalies in link with the heat wave episode of summer 2003 and associated increased convection.
Precisely, simulations over Europe over 3 years, 2002 to 2004, are compared with the original dataset gathered in particular over high-altitude sites during the CARBOSOL project. We particularly focus our attention on the vertical unresolved-scale transport parameterisation and analyse the strong seasonality in 210Pb concentrations (maximum in summer, minimum in winter), which was exceptionnally marked in 2003.
Dombrowski-Etchevers, I., Peuch, V.-H., Josse, B., and Legrand, M.: Evaluation of the parametrized transport of lead-210 in high-altitude European sites, Geosci. Model Dev. Discuss., 2, 247-278, doi:10.5194/gmdd-2-247-2009, 2009.