Download data with a dry-run simulation

Tip

If you are located at an institution with many other GEOS-Chem users, then the necessary input data might have already been downloaded and stored in a commmon directory on your system. Ask your sysadmin or IT support staff.

Tip

Another way to download and manage GEOS-Chem input data is with the bashdatacatalog tool.

A “dry-run” is a is a GEOS-Chem Classic simulation that steps through time, but does not perform computations or read data files from disk. Instead, a dry-run simulation prints a list of all data files that a regular GEOS-Chem simulation would have read. The dry-run output also denotes whether each data file was found on disk, or if it is missing. This output can be fed to a script which will download the missing data files to your computer system.

You may generate dry-run output for any of the GEOS-Chem Classic simulation types (fullchem, CH4, TransportTracers, etc.)

In the following chapters, you will learn how to you can download data using the output from a dry-run simulation:

• Execute a dry-run simulation
  • Complete preliminary setup
  • Run the executable with the --dryrun flag
• Download data from dry-run output
  • Choose a data portal
  • Run the download_data.py script on the dryrun log file
  • Skip download, but create log of unique files