122 Table 38 



GEOSTROPHIC WIND, CONSTANT PRESSURE SURFACE 

 200 geopotential foot contours 



The scalar equation for the geostrophic wind on a constant pressure surface is 



1 9$ 

 / dn 



V,= l - d * 



where <£> is the geopotential in a constant pressure surface, n is distance measured in the 

 horizontal direction, / is the coriolis parameter, and V t is the component of the geostrophic 

 wind normal to the direction in which n is measured. 



On a constant pressure surface with contours drawn for intervals of 200 geopotential 

 feet (gpft.) this reduces to 



r/ ,, , » 0.010436 



V„( knots) = — — 



/An 



(continued on next page) 



(To convert knots to other measures of speed see Table 35.) 

 (continued) 



SMITHSONIAN METEOROLOGICAL TABLES 



