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The surface drag contribution to the depth of Atlantic, and European, depressions
Author(s) -
Dodds I.
Publication year - 1972
Publication title -
quarterly journal of the royal meteorological society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.744
H-Index - 143
eISSN - 1477-870X
pISSN - 0035-9009
DOI - 10.1002/qj.49709841520
Subject(s) - geostrophic wind , drag , vorticity , allowance (engineering) , boundary layer , geology , inflow , surface (topology) , surface pressure , flow (mathematics) , circulation (fluid dynamics) , mechanics , physics , environmental science , climatology , mathematics , geometry , economics , vortex , operations management
Estimates are made of the forced ω F ‐components arising from surface frictional inflow within the circulation of an ‘average’ Atlantic and an ‘average’ European depression. When allowance is made for the high curvature flow by the inclusion of a centripetal acceleration term in the equation of motion, it is found that the ω F ‐contribution at the top of the boundary layer, is much the same in each case. The quasi‐geostrophic ω‐equation is solved to obtain the three‐dimensional ω F ‐field accompanying the average depression. This gives a value of ∂ω F /∂ p at the centre of the depression, and using this in the geostrophic vorticity equation it is found that surface friction makes a positive contribution of about 4 mb day −1 to the central pressure tendency in each case.