Term: altostratus cloud
https://doi.org/10.1351/goldbook.A00257

Definition:
A grey, uniform, striated or fibrous sheet but without halo phenomena, and through which the sun is seen only as a diffuse, bright patch or not at all; usually at elevations 2000-6000 m; vertical velocities of 0.05-0.1 m s-1.

Source: PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2180 (https://doi.org/10.1351/pac199062112167)

Citation: 'altostratus cloud' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.A00257

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