Dear Daniel > Does "Parametric Vertical Coordinates" mean that there is a mathematical > function, which describes the relation between the relevant (auxiliary) > coordinate variables and the parametric vertical coordinate?
In section 4.3.3, it means that the physical vertical coordinate z(k,j,i), where i,j are indices of the horizontal dimensions and k of the vertical, can be written as as a mathematical function z=f(V1(k)[,V2(k),...],H1([t,]j,i)[,H2([t,]j,i)...]) where V1,... depend only on level, and H1,H2,... depend only on horizontal position (and perhaps on time). I think that describes all the cases of Appendix D, but someone may correct me! The entries in App D describe the physical vertical coordinate and how to compute it with the formula f. > Speaking in terms of the example provided further below: Value of `depth` is > a `f(time, lev, lat, lon)`, whereas `f` is a mathematical function with > considerably less parameters than `depth` has values. Then `depth` is a > parametric vertical coordinate. > > Formulated the other way arond: Is `depth` NOT a parametric vertical > coordinate if its values are somehow set by hand (by a human), calculated by > some nested if-clause, or by some iterative procedure? > > If `depth` is not a parametric vertical coordinate in this sense, am I > allowed to use it in a CF-compliant file? The depth variable in your example is a 4D auxiliary coordinate variable. It is CF-compliant, but it's not a CF parametric vertical coordinate variable. > Example: > > ... > int lev(lev): > lev:standard_name = "model_level_number" ; > lev:long_name = "model_level_number" ; > lev:positive = "down" ; > lev:units = "1" ; > double depth(time, lev, lat, lon); > depth:long_name = "depth" ; > depth:positive = "down" ; > depth:standard_name = "depth" ; > depth:units = "m" ; > depth:axis = "Z" ; > float some_data_variable(time, lev, lat, lon); > some_data_variable:standard_name = "some_standard_name" ; > some_data_variable:units = "some_unit" ; > some_data_variable:coordinates = "depth" Best wishes Jonathan _______________________________________________ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
