Shear production

From Glossary of Meteorology
Revision as of 17:52, 25 April 2012 by imported>Perlwikibot
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)



shear production

The generation of turbulence kinetic energy caused by wind shear.

This mechanical production term S of the turbulence kinetic energy budget equation is (written in Einstein's summation notation)
ams2001glos-Se20
and is almost always positive, that is, a source. In the fair-weather, turbulent atmospheric boundary layer, the terms associated with horizontal wind usually dominate, allowing the shear production term to be approximated as
ams2001glos-Se21
where (
ams2001glos-Sex03
,
ams2001glos-Sex04
) are the Reynolds stresses (turbulent kinematic momentum fluxes) in the (x, y) directions, (U, V) are the respective wind components, the prime denotes deviation from the mean, and the overbar denotes an average. The ratio of the buoyant to the negative of the shear production terms is also known as the flux Richardson number and is a measure of dynamic stability.


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.