R and GFS.

Playing with NOAA's GFS data with R.

Credit:

• http://braz.blogspot.com/2009/12/r-for-global-climate-forecasting.html 
• http://joewheatley.net/ncep-global-forecast-system/

Here are some sample images.

Pre-requisites

• Fetched data from NOAA (in particular this dataset).
• Installed wgrib2.
• Extracted the fields I was interested in from the grib2 file into netcdf

./grib2/wgrib2/wgrib2  -s  gfs.t12z.sfluxgrbf03.grib2  | grep :LAND | ./grib2/wgrib2/wgrib2 -i gfs.t12z.sfluxgrbf03.grib2 -netcdf land.netcdf
./grib2/wgrib2/wgrib2  -s  gfs.t12z.sfluxgrbf03.grib2  | grep TMP:2 | ./grib2/wgrib2/wgrib2 -i gfs.t12z.sfluxgrbf03.grib2 -netcdf temp2.netcdf
./grib2/wgrib2/wgrib2  -s  gfs.t12z.sfluxgrbf03.grib2  | grep VEG: | ./grib2/wgrib2/wgrib2 -i gfs.t12z.sfluxgrbf03.grib2 -netcdf vegetation.netcdf
./grib2/wgrib2/wgrib2  -s  gfs.t12z.sfluxgrbf03.grib2  | grep TCDC: | ./grib2/wgrib2/wgrib2 -i gfs.t12z.sfluxgrbf03.grib2 -netcdf cloud.netcdf

• You can also view the available fields using:

./grib2/wgrib2/wgrib2  -s  gfs.t12z.sfluxgrbf03.grib2  | less

• Or by visiting the description.

Having fun

Started R and installed netcdf and fields:

install.packages('ncdf')
install.packages('fields')

Then used the following gist in R.

Playing with data from NOAA Global Forecast System using python

Bugger! Blogger barfs out an error when I attempt to upload my ipython notebook. You can find the notebook on github or as a rendered html here.

Here are some pretty generated images:

Horn of Africa zoomed in (Mar 27 2013)

Global 2M temperature in degrees C (Mar 27 2013)