A parameter consists of a Discipline( ie Meteorological_products), 
a Category( ie Temperature ) and a number that refers to a 
name( ie Temperature), Description( ie Temperature at 2 meters), and 
Units( ie K ).  

The reference to add/overwrite parameters are located at:
http://www.unidata.ucar.edu/software/netcdf-java/reference/GribTables.html


 