1. NCL NCL stands for NCAR Command Language. It is similar to IDL and MATLAB. It is most convenient for reading NetCDF files and plotting maps, but there are various routines for creating many other types of plots. There are also many “built-in” functions to process data including many statistical routines. More information at http://www.ncl.ucar.edu/

2. $NCARG_NCARG = $NCARG_ROOT/lib/ncarg/ NetCDF (.nc,.cdf) HDF (.hdf) GRIB (.grib) var = new(dims, vartype)

3. NCL variable metadata Variable: precipi Type: float Total Size: 18714240 bytes 4678560 values Number of Dimensions: 3 Dimensions and sizes: [TIME_EOSGRID | 24] x [YDim_EOSGRID | 361] x [XDim_EOSGRID | 540] Coordinates: TIME_EOSGRID: [ 0..1380] YDim_EOSGRID: [ -90.. 90] XDim_EOSGRID: [-180..179.3333333333333] Number Of Attributes: 12 _FillValue : 1e+15 long_name : Total surface precipitation flux standard_name : total_precipitation units : mm/hr scale_factor : 1 add_offset : 0 missing_value : 1e+15 fmissing_value : 1e+15 vmin : -1e+30 vmax : 1e+30 valid_range : ( -1e+30, 1e+30 ) hdf_name : PRECTOT precipi!1 = “YDim_EOSGRID” precipi&YDim_EOSGRID = lat precipi@units

8. For more documentation, go to http://www.ncl.ncar.edu To run: ncl < program.ncl