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GEOS-Chem Wiki

The GEOS–Chem model is a global 3-D model of atmospheric composition driven by assimilated meteorological observations from the Goddard Earth Observing System (GEOS) of the NASA Global Modeling and Assimilation Office. It is applied by research groups around the world to a wide range of atmospheric composition problems, Central management and support of the model is provided by the Atmospheric Chemistry Modeling Group at Harvard University.

This wiki is meant to facilitate communication between GEOS-Chem users and developers. If this is your first time here, check out the features page. If you would like to contribute to the wiki, please register as a user by clicking create account at the top right corner of this page.

New information is continually being added to the wiki, so please check back here often, or even better, subscribe to the recent changes' RSS feed: you will not miss a discussion!

General Information about GEOS-Chem

The links below provide more information about general GEOS-Chem topics.

Introduction and Overview

• Features of the GEOS-Chem public wiki
• GEOS-Chem welcome letter for new users
• GEOS-Chem Overview
• GEOS-Chem People & Projects
• User Resources, Code Development Guidelines, and Debugging Tips
• GEOS-Chem programming staff
• GEOS-Chem newsletters

Steering Committee and Working Groups

• GEOS-Chem Steering Committee
  • GEOS-Chem model development priorities
• GEOS-Chem Working Groups
  • Adjoint Model and Data Assimilation Working Group
  • Aerosols Working Group
  • Carbon Gases and Organics Working Group
  • Emissions Working Group
  • Oxidants and Chemistry Working Group
  • Regional Air Quality Working Group

Getting Started with GEOS-Chem

• Minimum system requirements for GEOS-Chem
• GEOS-Chem supported platforms and compilers
• Downloading GEOS-Chem source code and data
• GEOS-Chem code development cycle
• GEOS-Chem programming resources (e.g. tutorials, user guides, etc.)
• GEOS-Chem Programming Style Guide
• Running GEOS-Chem with TESTRUN

General Technical Information

• Initial conditions for GEOS-Chem
• Tips on how to debug GEOS-Chem effectively
• Reporting GEOS-Chem bugs
• Parallelizing GEOS-Chem with the OpenMP directives
• Common GEOS-Chem error messages
• GEOS-Chem Search Engines

Code Developers' Forums

These pages contain more specific information about coding issues, emissions, chemistry, met fields, version history, and other aspects of GEOS-Chem. GEOS-Chem users and developers should feel free to contribute to these pages and to initiate discussion on the various topics listed here.

Coding

• GEOS-Chem versions under development
  • v8-02-03 "beta"
  • v8-02-02 "beta"
  • v8-02-01 "public"
  • v8-01-04 "beta"
  • v8-01-03 "beta"
  • v8-01-02 "beta"
  • v8-01-01 "public"
• Machine issues & portability
• Floating point math issues
• Bugs and fixes
• Outstanding issues yet to be resolved

Diagnostics

• Overview of diagnostics characteristics
• Mass Flux (ND24/25/26)
• Additional diagnostics

Emissions

• Overview
• Aircraft emissions
• Anthropogenic emissions
  • Description of anthropogenic emissions inventories in GEOS-Chem v8-02-03
  • Description of anthropogenic emissions inventories in GEOS-Chem v8-01-04
  • Table of available anthropogenic emissions inventories for use w/ GEOS-Chem (pre-v8)
• Biofuel emissions
• Biogenic emissions
• Biomass burning emissions
• Lightning NOx emissions

Chemistry

• Chemistry Issues
• NOx-Ox-hydrocarbon-aerosol (aka "full-chemistry") simulation
• Photolysis mechanism
• Mercury simulation
• Tagged CO simulation
• KPP solvers FAQ

Aerosols

• Aerosols overview: projects and developments
• Aerosol-only simulation
• Aerosol thermodynamical equilibrium
• Secondary organic aerosols
• Sea salt aerosols
• Sulfate aerosols

Met Fields

• GCAP
• GMAO GEOS-5
  • List of GEOS-5 met fields
  • GEOS-5 issues
  • GEOS-5 met field reprocessing
• GEOS-Chem Met Fields (from website)
  • Notes regarding GEOS vertical grids

Nested Grid Simulations

• GEOS-Chem nested grid simulations
• Available met data for nested grid simulations
  • Protocol for nested-grid data downloads

Earth System Model Framework

• Installing ESMF and other required libraries
• Code development with the Earth System Model Framework
• Generating automatic LaTeX documentation with protex
  • Web-based LaTeX tutorial

Related Projects

• GEOS-Chem column code
• GEOS-Chem Adjoint
• GEOS-Chem Near-Real-Time Simulations

Data Visualization and Analysis

IDL

• ITT Visualization (vendor)
• Structures in IDL
• Pointers in IDL
• Overview of Mathematics in IDL
• Coyote's Guide to IDL Programming (David Fanning's Web Site) - Lots of tips on how to accomplish programming tasks
• IDL Page at Max Planck Institute for Meteorology
• Martin Schultz's IDL Tutorial (PDF Format)
• IDL Astronomy User's Library
• JHU/APL/S1R IDL routines page
• Craig Markwardt's IDL library
• The Underground Guide to IDL by Liam Gumley (PDF)
• Reading binary files in IDL

GAMAP

• GAMAP web page
• GAMAP on-line users' guide
• GAMAP bugs and fixes
• GAMAP tips and tricks
  • General GAMAP usage
  • File I/O with GAMAP
    • Working with timeseries output in GAMAP
  • Color and graphics with GAMAP
    • Loading Color Tables in GAMAP v2.12
    • Working with color in IDL by Chris Holmes
  • Regridding with GAMAP
  • Date and time computations with GAMAP
  • Text manipulation with GAMAP

Wiki Documentation

• Sandbox
• MediaWiki FAQ
• MediaWiki User's Guide
• Examples of Wiki markup text
• One-page editing reference card
• Configuration Settings list
• MediaWiki release mailing list