Log files

Log files redirect the output of Fortran PRINT* or WRITE statements to a file. You can check the log files for an “echo-back” of simulation options, as well as error messages.

GEOS-Chem and HEMCO log file

File name: GC.log (or similar)

Contains an “echo-back” of input options that were specified in geoschem_config.yml and HISTORY.rc, as well as information about what is happening at each GEOS-Chem timestep. If your GEOS-Chem Classic simulation dies with an error, a detailed error message will be printed in this log file.

In GEOS-Chem 14.1.0 and later versions, information about emissions, met fields, and other relevant data that are read from disk and processed by HEMCO is now sent to this log file (instead of to HEMCO.log).

GEOS-Chem log file with dry-run output

File name: log.dryrun (or similar)

Contains the full path names of all input files (configuration files, meteorology files, emissions files) that are read by GEOS-Chem. This will allow users to download only those files that their GEOS-Chem simulation requires, thus speeding up the data downloading process.

For more information, please see the dry run chapter.

GEOS-Chem species metadata log

File name: OutputDir/geoschem_species_metadata.yml

Contains metadata (taken from the GEOS-Chem species database) in YAML format for only those species that are used in the simulation. This facilitates coupling GEOS-Chem to other Earth System Models.

Timers log file

File name: gcclassic_timers.json (in JSON format).

The timers log file is created when you set use_gcclassic_timers: true in the Simulation Settings section of geoschem_config.yml. It contains “wall-clock” times that measure how long each component of GEOS-Chem took to execute. This information is used by the GEOS-Chem benchmarking scripts that execute on the Amazon cloud computing platform.

Scheduler log file

File name: Specific to each scheduler.

If you used a batch scheduler such as SLURM, PBS, LSF, etc. to submit your GEOS-Chem Classic simulation, then output from the Unix stdout and/or stderr streams may be printed to this file. This file may contain important error messages.