Here is the head of the hgt.nc for your reference

> ncdump -h hgt.nc
netcdf hgt {
dimensions:
        jx = 125 ;
        iy = 217 ;
        plev = 11 ;
        time = UNLIMITED ; // (112 currently)
        nb2 = 2 ;
variables:
        float jx(jx) ;
                jx:standard_name = "grid_longitude" ;
                jx:long_name = "x-coordinate in Cartesian system" ;
                jx:units = "m" ;
                jx:axis = "X" ;
        float iy(iy) ;
                iy:standard_name = "grid_latitude" ;
                iy:long_name = "y-coordinate in Cartesian system" ;
                iy:units = "m" ;
                iy:axis = "Y" ;
        float plev(plev) ;
                plev:standard_name = "air_pressure" ;
                plev:long_name = "Interpolated pressure" ;
                plev:units = "hPa" ;
                plev:positive = "down" ;
                plev:axis = "Z" ;
        double time(time) ;
                time:standard_name = "time" ;
                time:long_name = "time" ;
                time:bounds = "time_bnds" ;
                time:units = "hours since 1949-12-01 00:00:00" ;
                time:calendar = "standard" ;
        double time_bnds(time, nb2) ;
                time_bnds:units = "hours since 1949-12-01 00:00:00" ;
                time_bnds:calendar = "standard" ;
        float hgt(time, plev, iy, jx) ;
                hgt:_FillValue = 1.e+20f ;
                hgt:coordinates = "xlon xlat" ;

// global attributes:
                :CDI = "Climate Data Interface version 1.6.0 (http://code.zmaw.de/projects/cdi)" ;
                :Conventions = "CF-1.4" ;
                :history = "Thu Jul 11 13:48:24 2013: cdo expr,hgt=hgt climate_ATM.1989020100_pressure.nc hgt.nc\n",
                        "2013-07-08 19:49:07 : Created by RegCM RegCM Model program" ;
                :CDO = "Climate Data Operators version 1.6.0 (http://code.zmaw.de/projects/cdo)" ;
}


--
Lang WANG
PhD Candidate
Department of Environment and Geography
Faculty of Science
Macquarie University
Sydney
NSW 2109
Australia

lang.wang@students.mq.edu.au
http://www.mq.edu.au/

Tel. +61 (0)2 9850 6372