The study of the meteorological processes on scales from a millimeter or less up to tens or hundreds of metres; e.g. meteorology of a local site that is usually small and often is confined to a shallow layer of air next to the ground.
Source:
PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2202 (https://doi.org/10.1351/pac199062112167)