GVOUTC

     GVOUTC is the vertical coordinate of the output grid.

     The standard values are:
 
	NONE	for surface data
	PRES	data in pressure coordinates (millibars)
	THTA	data in isentropic coordinates (Kelvin)
	HGHT	data in height coordinates (meters)
	SGMA	data in sigma coordinates

     Any nonstandard value may be used as well, as long as it is four
     characters long and includes only letters and/or numbers.  For
     example, PVAB and PVBL may be used to represent PV as a vertical
     coordinate, where PVAB is the PV surface found searching from above
     and PVBL is the PV surface found searching from below.