The London Perl and Raku Workshop takes place on 26th Oct 2024. If your company depends on Perl, please consider sponsoring and/or attending.

NAME

Weather::NOAA::GFS - Perl extension for forecast climate maps from NOAA GFS site

SYNOPSIS

  use Weather::NOAA::GFS;

  
  # define parameters 
    my %params = (
                'minlon'   => -5,# mandatory
                'maxlon'   => 45,# mandatory
                'minlat'   => 30,# mandatory
                'maxlat'   => 50,# mandatory
                'mail_anonymous'    => 'my@mail.org',# mandatory to log NOAA ftp server
                'gradsc_path' => 'gradsc',# mandatory, needed to create maps
                'wgrib_path' => 'wgrib',# mandatory, needed to process NOAA GRIB files
                'debug'    => 1, # 0 no output - 1 output
                'logfile'    => 'weather-noaa-gfs.log',# optional
                'cbarn_path' => 'cbarn.gs', #optional, needed to print image legend
                'r_path' => 'R',# optional, needed to downscale
                
  );
  
  
  # instantiate a new NOAA::GFS object
  my $weather_gfs = Weather::NOAA::GFS->new(%params);
  
  #download Grib files for your area

  if($weather_gfs->downloadGribFiles()){
        print "downloadGribFiles done!!!";
  } else {
        print "Error: downloadGribFiles had problems!!!";
        die;
  }
  
  #transform Grib files to Ascii files (needs GrADS's wgrib)
  
  if($weather_gfs->grib2ascii()){
        print "grib2ascii succeded!!!";
  } else {
        print "Error: grib2ascii had problems!!!";
        die;
  }

  #transform Ascii files to IDRISI files
  
  if($weather_gfs->ascii2idrisi()){
        print "ascii2idrisi succeded!!!";
  } else {
        print "Error: ascii2idrisi had problems!!!";
        die;
  }

  
  #itransform Idrisi files to Png images (needs GrADS's gradsc)
  if($weather_gfs->idrisi2png()){
        print "idrisi2png succeded!!!";
  } else {
        print "Error: idrisi2png had problems!!!";
        die;
  }

DESCRIPTION

This module produces forecast climate maps from NOAA GFS site (http://nomad2.ncep.noaa.gov/ncep_data/). It downloads rough data, transforms it into IDRISI (binary GIS format) and then in PNG maps. Output maps are for temperature, relative humidity, zonal wind, pressure and rainfall precipitation. The module requires some extra software installed: GrADS (mandatory) (http://grads.iges.org/grads/grads.html) to create PNG output and R (optional) (http://www.r-project.org/) to downscale the 1 degree resolution to 0.1 degree.

TO DO

1) integration with R 2) better image output

SEE ALSO

Software needed:

GrADS - http://grads.iges.org/grads/grads.html used: wgrib, gradsc. Need cbarn.gs

R - http://www.r-project.org/ add module GStat

AUTHORS

Alfonso Crisci, <crisci@ibimet.cnr.it> Valerio Capecchi, <capecchi@ibimet.cnr.it> Lorenzo Becchi, <lorenzo@ominiverdi.com>

COPYRIGHT AND LICENSE

Copyright (C) 2004 by Lorenzo Becchi

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.5 or, at your option, any later version of Perl 5 you may have available.