Gridded post-processor
The program post-processes an AROME or ECMWF NetCDF file by using various downscaling and calibration methods. Post-processed forecasts are placed in a second Netcdf file, which has the desired output grid.
To convert between the two grids, a downscaling method is used. Currently implemented methods are:
- nearest neighbour
- elevation gradient (interpolation to new elevations using gradients)
- smart neighbours (nearest grid points at the same elevation)
- pressure (interpolation to new elevations using a standard atmosphere)
Calibrators include:
- spatial smoothing (average within a neighbourhood)
- ensemble calibration of precipitation using zero-adjusted Gamma distribution
- polynomial regression of any order
- calculation of precipitation phase, using wetbulb temperature
- calculation of QNH from surface pressure
Installation Instructions
- Ensure the following libraries are installed:
- Boost libraries
- Netcdf c++ library
- (Optional) Google test library (if developing new code)
- Edit CC, CFLAGS_O, IFLAGS, and LFLAGS in makefile
- Run 'make'
Running the program
To see program options, run:
./gridppTo test the program on a fake dataset, run:
./gridpp testing/files/10x10.nc testing/files/10x10_copy.nc -v T -d gradient -v Precip -d smart numSmart=3 searchRadius=3
ncview testing/files/10x10_copy.ncExample
To test the program on a real operational AROME file, follow these steps:
- Make a copy of a file to post-process:
cp /starc/DNMI_AROME_METCOOP/2015/01/01/AROME_MetCoOp_00_DEF.nc_20150101 localcopy.nc- Create a smoothed precipitation field in localcopy.nc:
./gridpp /starc/DNMI_AROME_METCOOP/2015/01/01/AROME_MetCoOp_00_DEF.nc_20150101 localcopy.nc -v Precip -c smooth smoothRadius=10Running on multiple cores
To run using 8 threads:
export OMP_NUM_THREADS=8
./gridpp ...Minimizing memory usage
Run the program in sequence for each variable:
./gridpp input output -v T ...
./gridpp input output -v Precip ...
./gridpp input output -v RH ...Copyright and license
Copyright (C) 2015 MET Norway. Gridded post-processor is licensed under GPL version 2 or (at your option) any later version.