Editing Geopotential height (section)

==Definition==
''[[Geopotential]]'' is the [[gravitational energy|gravitational potential energy]] per unit mass at elevation <math>Z</math>:
:<math>\Phi(Z) = \int_0^Z\ g(\phi,Z)\,dZ</math>
where <math>g(\phi,Z)</math> is the acceleration due to [[gravity]], <math>\phi</math> is [[latitude]], and <math>Z</math> is the geometric elevation.<ref name=NASA/>

'''Geopotential height''' may be obtained from normalizing geopotential by the acceleration of gravity:
:<math>{H} = \frac{\Phi}{g_{0}}\ = \frac{1}{g_{0}}\int_0^Z\ g(\phi,Z)\,dZ</math>
where <math>g_0</math> = 9.80665 m/s<sup>2</sup>, the [[standard gravity]] at mean sea level.<ref name="https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19760017709.pdf">{{cite web|title=NASA Technical Report R-459: Defining Constants, Equations, and Abbreviated Tables of the 1976 Standard Atmosphere|date=May 1976 |url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19760017709.pdf|archive-url=https://web.archive.org/web/20170307211228/https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19760017709.pdf |archive-date=2017-03-07 |last1=Minzner |first1=R. A. |last2=Reber |first2=C. A. |last3=Jacchia |first3=L. G. |last4=Huang |first4=F. T. |last5=Cole |first5=A. E. |last6=Kantor |first6=A. J. |last7=Keneshea |first7=T. J. |last8=Zimmerman |first8=S. P. |last9=Forbes |first9=J. M. }} </ref> Expressed in differential form, 
:<math>{g_0}\ {dH} = {g}\ {dZ}</math>