Articles | Volume 10, issue 6
Geosci. Model Dev., 10, 2397–2423, 2017
Geosci. Model Dev., 10, 2397–2423, 2017

Model description paper 28 Jun 2017

Model description paper | 28 Jun 2017

CHIMERE-2017: from urban to hemispheric chemistry-transport modeling

Sylvain Mailler1,2, Laurent Menut1, Dmitry Khvorostyanov1, Myrto Valari1, Florian Couvidat3, Guillaume Siour4, Solène Turquety1, Régis Briant1, Paolo Tuccella1, Bertrand Bessagnet3, Augustin Colette3, Laurent Létinois3, Kostantinos Markakis1, and Frédérik Meleux3 Sylvain Mailler et al.
  • 1LMD/IPSL, École Polytechnique, Université Paris Saclay, ENS, PSL Research University; Sorbonne Universités, UPMC Univ Paris 06, CNRS, Palaiseau, France
  • 2École des Ponts ParisTech, Université Paris-Est, 77455 Champs-sur-Marne, France
  • 3INERIS, National Institute for Industrial Environment and Risks, Parc Technologique ALATA, 60550 Verneuil-en-Halatte, France
  • 4Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil et Université Paris Diderot, Institut Pierre Simon Laplace, Créteil, France

Abstract. CHIMERE is a chemistry-transport model designed for regional atmospheric composition. It can be used at a variety of scales from local to continental domains. However, due to the model design and its historical use as a regional model, major limitations had remained, hampering its use at hemispheric scale, due to the coordinate system used for transport as well as to missing processes that are important in regions outside Europe. Most of these limitations have been removed in the CHIMERE-2017 version, allowing its use in any region of the world and at any scale, from the scale of a single urban area up to hemispheric scale, with or without polar regions included. Other important improvements have been made in the treatment of the physical processes affecting aerosols and the emissions of mineral dust. From a computational point of view, the parallelization strategy of the model has also been updated in order to improve model numerical performance and reduce the code complexity. The present article describes all these changes. Statistical scores for a model simulation over continental Europe are presented, and a simulation of the circumpolar transport of volcanic ash plume from the Puyehue volcanic eruption in June 2011 in Chile provides a test case for the new model version at hemispheric scale.

Short summary
CHIMERE is a chemistry-transport model initially designed for box-modelling of the regional atmospheric composition. In the recent years, CHIMERE has been extended to be able to model atmospheric composition at all scales from urban to hemispheric scale, which implied major changes on the coordinate systems as well as on physical processes. This study describes how and why these changes have been brought to the model, largely increasing the range of its possible use.