Geostrophic Adjustment
A.Parcel at rest initially accelerates toward lower pressure.
B.Coriolis Force rotates parcel to right in NH.
C.As parcel speeds up, Coriolis Force increases.
D.Eventually (about a day),      PGF equals CF and flow is parallel to isobars.
World Weather Project 2010 Courtesy of M. Ramamurthy         U of Illinois, Urbana-Champaign
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