(Invited Speaker) Physical and chemical weather forecasting as a joint problem: two-way interacting integrated modelling

During the last decade a new field of atmospheric modelling - the chemical weather forecasting (CWF) - is quickly developing and growing. However, in the most of the current studies and publications this field is considered in a simplified concept of the off-line running chemical transport models with operational NWP data as a driver [1]. A new concept and methodology considering the chemical weather as two-way interacting nonlinear meteorological and chemical/aerosol dynamics processes of the atmosphere is suggested [2] and discussed. The on-line integration of mesometeorological models and atmospheric aerosol and chemical transport models gives a possibility to utilize all meteorological 3D fields in the chemical transport model at each time step and to consider nonlinear feedbacks of air pollution (e.g. atmospheric aerosols) on meteorological processes / climate forcing and then on the chemical composition. This very promising way for future atmospheric simulation systems (as a part of and a step to Earth System Modelling) will lead to a new generation of models for meteorological, environmental, chemical and biological weather forecasting. The methodology how to realise the suggested integrated CWF concept is demonstrated on example of the European Enviro-HIRLAM integrated system [3,4]. European experience in the field of the online integrated meteorology-chemistry modeling, importance of different chains of feedback mechanisms for meteorological and atmospheric chemistry processes and their strong nonlinearities are also discussed in the paper.

References 1. Lawrence, M. G., Hov, Ø., Backmann, M., Brandt, J., Elbern, H., Eskes, H., Feichter, H., and Takigawa, M.: The Chemical Weather. Environ. Chem., 2, 6–8, 2005. 2. Baklanov, A.: Chemical weather forecasting: a new concept of integrated modelling, Advances in Science and Research, 4, 23-27, 2010. 3. Baklanov, A., Korsholm, U., Mahura, A., Petersen, C., and Gross, A.: ENVIRO-HIRLAM: on-line coupled modelling of urban meteorology and air pollution, Advances in Science and Research, 2, 41–46, 2008. 4. Korsholm, U.: Integrated modeling of aerosol indirect effects – development and application of a chemical weather model, PhD thesis University of Copenhagen, Niels Bohr Institute and Danish Meteorological Institute, Research department, http://www.dmi.dk/dmi/sr09-01.pdf, 2009.