GEOS-Chem Classic Logo

Getting Started

  • Quickstart Guide
  • Meet all hardware requirements
  • Meet all software requirements
  • Customize your login environment
  • Key references

GEOS-Chem Classic User Guide

  • Download source code
    • Source code repositories
    • Download instructions
  • Create a run directory
  • Compile the source code
  • Configure your simulation
  • Download input data
  • Run your simulation
  • View output files
  • Diagnostics reference

GEOS-Chem Simulations

  • Simulations overview
  • Aerosol-only simulation
  • Carbon gases simulation
  • Fullchem simulation
  • Hg (mercury) simulation
  • Metals simulation
  • Tagged O3 simulation
  • TransportTracers simulation

Supplemental Science Guides

  • Particulate matter in GEOS-Chem

Supplemental Technical Guides

  • Technical Guides overview
  • GEOS-Chem Classic folder tree
  • GEOS-Chem Classic horizontal grids
  • GEOS-Chem Classic vertical grids
  • Sample GEOS-Chem run scripts
  • Run GEOS-Chem Classic on the cloud
  • Load software into your environment
  • Build required software with Spack
  • Customize simulations with research options
  • Understand what error messages mean
  • Debug GEOS-Chem and HEMCO errors
  • Manage a data archive with bashdatacatalog
  • Archive output with the History diagnostics
  • Work with netCDF files
  • Prepare COARDS-compliant netCDF files
  • View GEOS-Chem species properties
  • Parallelize GEOS-Chem and HEMCO source code
  • Run nested-grid simulations
  • Update chemical mechanisms with KPP
  • Use the KPP-Standalone box model to test chemical mechanisms
  • View related documentation

Help & Reference

  • GEOS-Chem version history
  • Known bugs and issues
  • Contributing Guidelines
  • Support Guidelines
  • Editing this User Guide
GEOS-Chem Classic
  • Download source code
  • View page source

Download source code

In the following chapters, you will learn how to download the GEOS-Chem source code from Github.

  • Source code repositories
    • GEOS-Chem repositories
    • Other code packages used by GEOS-Chem
  • Download instructions
    • Clone GCClassic and fetch submodules
    • Create a branch in src/GEOS-Chem for your work
    • See additional resources
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