This session is devoted to basic and applied research on atmospheric processes, phenomena and impacts linking the chemical to the physical state of the atmosphere. Particular interest lies in the observations and modelling of the transport, dispersion, transformation and deposition of atmospheric compounds (including air pollutants, pollen, GHGs, radionuclides and other substances naturally or accidentally released) as these processes, their variability and interactions at all spatial and temporal scales are crucial to the development of models used to simulate and predict the past, present and future state and composition of the Earth’s atmosphere.

Within this scope, the session draws from diverse elements of atmospheric science research related to weather, atmospheric composition and climate, and includes theoretical, numerical modelling and experimental studies on scales extending from local to global, including the urban areas. Contributions on the development of observations and modelling techniques as well as on mitigation strategies varying from nature-based solutions to emission reductions also fit the scope of the session.

Targeted towards both disciplinary and interdisciplinary audiences, this session invites oral and poster contributions on topics including, but not limited to, the following:
• Understanding, describing and modelling the role of meteorological, chemical and physical processes and phenomena on emissions, transport, dispersion, transformation, deposition and biogeochemical cycling of air pollutants,
• feedback processes between air pollution, meteorology, and climate,
• characterization of the effect of urban planning choices and other heterogeneities on air pollutant transport, dispersion and concentration in urban areas,
• air pollution and atmospheric composition monitoring networks and platforms using novel Instrumentation,
• air quality and transport model development and evaluation using meteorological and chemical observations,
• air quality forecasting (incl. online modelling integrating chemical weather with NWP modelling) and chemical data assimilation,
• Observations and modelling of urban meteorology including street canyon circulation, heat and mass fluxes within and over cities,
• environmental meteorology in a changing climate.


In addition to covering the above possible topics, the session can also serve as a dissemination forum for relevant projects, including the Copernicus Atmosphere Monitoring Service (CAMS), COST Actions, WMO Global Atmosphere Watch (GAW) SAG-GURME & SAG-APP, FAIRMODE, as well as national- and European-scale consortium projects.