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Get anomalies

The get_anom.sh script is used to obtain anomalies for multiple files. It reads parameters from a configuration file and applies them to the input files to generate anomalies. The anomalies are saved in a subfolder named anom/ within the input file's folder, with anom_ prepended to the input file's name. Additionally, the corresponding climatological mean fields are saved in a subfolder named anom/mean/, with mean_ prepended to the input file's name.

Usage

./get_anom.sh CONFIGFILE INFILES

Arguments

  • CONFIGFILE: Shell script that defines the parameters.
  • INFILES: One or more input netCDF files for which anomalies will be obtained.

Configuration file

The CONFIGFILE provides the parameters required for anomaly creation. The following parameters are used by the script:

  • date: The start and end dates for the anomalies in the format startdate,enddate. Used in the cdo seldate command.
  • grid: The grid name used in the cdo remapcon command.
  • landmask: A boolean parameter (true or false) that restricts grid points to land.
  • logscale: A boolean parameter (true or false) that converts variables to log scale.
  • lonlatbox: Longitude and latitude limits used in the cdo sellonlatbox command in the format longitude_min,longitude_max,latitude_min,latitude_max.
  • min: The minimum value used for log scale conversion.
  • names: Variable name(s) used in the cdo selname command.

  • regions: The filename defining a region used in the cdo maskregion command.

  • refdate: The start and end dates for the climatological mean used in the cdo seldate command.

Output

  • The anomalies are saved in a subfolder named anom/ within the input file's folder, with anom_ prepended to the input file's name.
  • The corresponding climatological mean fields are saved in a subfolder named anom/mean/, with mean_ prepended to the input file's name.

Example

Here's an example to illustrate the usage of the get_anom.sh script:

Suppose we have the following configuration file named config.sh:

date="1850-01-01,2014-12-31"
grid="global_1"
landmask=false
logscale=false
lonlatbox="-180,180,-90,90"
min=
names="sst"
regions=
refdate="1900-01-01,1999-12-31"

And we want to create anomalies for all netCDF files in path/to/files/*.nc.

To execute the script with the given configuration file and input files, we run the following command:

./get_anom.sh config.sh path/to/files/*.nc

The script reads the parameters from config.sh and process the input files accordingly. Anomalies will be saved in the path/to/files/anom/ subfolder, with anom_ prepended to the original file names. The corresponding climatological mean fields will be saved in the path/to/files/anom/mean/ subfolder, with mean_ prepended to the original file names.

Note

  • Examples of CONFIGFILE file can be found in the configs/ folder of this repository.
  • Examples of regions files can be found in the regions/ folder of this respository.