Chemical Weather Forecasting: a New Concept and Methodology of Two-Way Integrated Meso-Scale Modelling

Authors: Baklanov A.A.

Year: 2009

Issue: 04

Pages: 109-120


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. A new concept and methodology considering the chemical weather as two-way interacted meteorological weather and chemical composition of the atmosphere is suggested 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 feedbacks of air pollution (e.g. urban aerosols) on meteorological processes/climate forcing and further 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 and chemical weather forecasting. The methodology how to realise the suggested integrated CWF concept is demonstrated on example of the European Enviro–HIRLAM integrated system. Importance of different feedback mechanisms for CWF is also discussed in the paper.

Tags: chemical weather forecasting; feedbacks mechanisms; off-line and on-line chemical transport modeling; two-way interacted meso-scale modelling


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