Beta plane

From Glossary of Meteorology

beta plane

The model, introduced by C. G. Rossby, of the spherical earth as a plane with a rate of rotation f (corresponding to the Coriolis parameter) that varies linearly with the north–south direction y:

The constant β (the Rossby parameter) is given its value at a central latitude on the spherical earth, (2Ω cosφ0)/a, where Ω is the angular speed of the earth and a its mean radius. Used chiefly in association with the vorticity equation, this model is usually accompanied by the assumption that the Coriolis parameter is constant, f = f0, when it appears in undifferentiated form. Although it applies precisely to no physical situation, this model has gained wide acceptance in dynamic meteorology.

Copyright 2022 American Meteorological Society (AMS). For permission to reuse any portion of this work, please contact Any use of material in this work that is determined to be “fair use” under Section 107 of the U.S. Copyright Act (17 U.S. Code § 107) or that satisfies the conditions specified in Section 108 of the U.S.Copyright Act (17 USC § 108) does not require AMS’s permission. Republication, systematic reproduction, posting in electronic form, such as on a website or in a searchable database, or other uses of this material, except as exempted by the above statement, require written permission or a license from AMS. Additional details are provided in the AMS Copyright Policy statement.