Original scientific paper

QUASI-GEOSTROPHIC FLOW PAST MOUNTAINS

Haraldur Ólafsson ; Háskóli Íslands (University of Iceland), Veðurstofa Íslands (Icelandic Meteorological Office) and Rannsóknastofa í veðurfræði (Institute for Meteorological Research)

Abstract

Blocked flow at moderate Rossby numbers is studied and an analytic expression is derived for the vertical velocities on each side of the wake:
W = (Uo h) / (f Lx Ly)
Where Uo is the incoming wind speed, h is the mountain height, f is Coriolis parameter, Ly is mountain half-width and Ly is a length scale of the vertical mortion downstream of the edges of the mountains. To illustrate the use of the above expression, a collection of flows over Iceland is presented and the calculated vertical velocities are compared to the number of days with precipitation in two different regions.

Keywords

quasi-geostrophic flow; Rossby number; Froude number; Nh/U; non-dimensional mountain height; asymetric ascending motion; Iceland; Coriolis force; blocking; conceptual model; wake; corner winds

Hrčak ID:

64697

URI

https://hrcak.srce.hr/64697

Publication date:

15.12.2005.

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