Turner angle

From Glossary of Meteorology
Revision as of 05:25, 8 March 2021 by Rbrandt (talk | contribs) (→‎Turner angle)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Turner angle

A parameter used to define the local stability of an inviscid water column to double-diffusive convection.

It is defined as
where tan−1 is the four-quadrant arctangent; α is the coefficient of thermal expansion; β is the equivalent coefficient for the addition of salinity, sometimes referred to as the "coefficient of saline contraction;" T is temperature; and S is salinity. If −45° < Tu < 45°, the column is statically stable. If −90° > Tu or Tu > 90°, the column is statically unstable to Rayleigh–Taylor instability. If −90° < Tu < −45°, the column is unstable to diffusive convection. If 45° < Tu < 90°, the column is unstable to salt fingering.

Term edited 8 March 2021

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.