ageostrophic, a. Meteorol.
(eɪdʒiːəʊˈstrɒfɪk)
[f. a- 14 + geostrophic a.]
Not geostrophic; spec. designating the wind component which when added to a geostrophic wind gives the actual wind.
| [1938 R. C. Sutcliffe in Q. Jrnl. R. Meteorol. Soc. LXIV. 502 If there is a general vertical motion in a region where the winds are quasi-geostrophic, then there is a non-geostrophic component directed along the horizontal gradient of temperature.] 1948 Jrnl. Inst. Navigation I. 54 Having minimised air position errors..it was possible..to make an assessment of the inherent errors of the technique i.e. those due to ageostrophic effects. 1956 Nature 7 Jan. 14/2 He first reduced the equations of motion to an approximate but observable form which involved the geostrophic and ageostrophic components of the wind-velocity and the radius of curvature of the isobars. 1963 Meteorol. Gloss. (Met. Office) (ed. 4) 9 The ageostrophic wind is of fundamental importance in that it is necessarily associated with convergence or divergence and vertical motion in the atmosphere. 1971 Nature 23 July 249/1 King-Hele considered the geostrophic component of the zonally averaged longitudinal wind as the prevailing wind which he observed... However,..this wind component must be rather small due to the large ageostrophic wind component which results from ion-neutral collisions. 1979 Ibid. 20 Sept. 190/1 This equation is invalid at fast rotation rates where motions are highly ageostrophic. |