The Multi-Scale Modelling (MSM) group at the Institute for Atmospheric and Earth System Research (INAR) researches and develops atmospheric and Earth-system models, ranging from microscopic scales to large global scales. The research aims of the group include studying chemical, physical, and meteorological processes in the atmosphere from small to large spatial and temporal scales, which will provide better scientific knowledge on aerosol formation and growth, air quality, clouds, weather, and climate. The MSM group works closely with other research groups in INAR.