Long wave

From Glossary of Meteorology



long wave

  1. (Or major wave;
    also called planetary wave.) With regard to atmospheric circulation, a wave in the major belt of westerlies that is characterized by large length and significant amplitude.

    The wave length is typically longer than that of the rapidly moving individual cyclonic and anticyclonic disturbances of the lower troposphere. The angular wavenumber of long waves is generally taken to be from 1 to 5.
    Compare short wave;
    see Rossby wave.

  2. (Also called shallow water wave.) A wave with a relatively long wave length and period.

    For ocean waves, this is typically a wave of period greater than about 10 s and wave length greater than about 150 m.


Copyright 2022 American Meteorological Society (AMS). For permission to reuse any portion of this work, please contact permissions@ametsoc.org. 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.