This repository includes the public release of the GFDL AM4 model code. The AM4 model is described in the two articles published in the Journal of Advances in Modeling Earth Systems (JAMES). More information on the model and access to the output is available on the AM4 data and code site at the Geophysical Fluid Dynamics Laboratory (GFDL).
The layout of this package includes the following directories:
- src - The source code for the AM4 model
- exec - The build directory with Makefiles for building the model executable
- run - Sample run script
- analysis - Sample analysis scripts
This repository uses git submodules to point to other repositories. Thus, care should be taken when cloning, and updating the source to ensure all source. To obtain all source, use the following git command
git clone --recursive https://github.com/NOAA-GFDL/AM4.git
The --recursive option to git clone instructs git to recursively
clone all submodules. In the event the repository was not cloned
using the --recursive option, the following step must be taken to
obtain all sources:
# From within the AM4 parent directory
git submodule update --init --recursive
All model source is contained in the src directory. GFDL tracks code using the git version control system. This package includes a single version of the following GFDL model components. The git hash listed corresponds to the commit hash in the internal GFDL git repository.
| Component | Commit Hash |
|---|---|
| atmos_drivers | 5ee95d6abf0879594551dd7e6635dff4004c4010 |
| atmos_param | 2e94acfd8621e85216bf822c395a8c3f15a511a5 |
| atmos_shared | a557d4d7bab033ef1ad1d400a62fe07a97ccb477 |
| ice_param | 1553c8bc4f9a66791c89367b6f327147523155ed |
| ice_sis | ccc7328dcd79706dd5c17c8bab660222886fc80b |
| land_lad2 | a220288ecb289bf9d793d051fc5076072874ce07 |
The following components are available in the NOAA-GFDL github organization:
The exec directory contains Makefiles that can be used to build the AM4 executable. These Makefiles were generated using the Make Makefile (mkmf) program. Included in the exec direcgtory is a sample make template file for the Intel compilers (intel.mk). This make template can be used on any system with a relatively recent version of the Intel compilers, the netCDF 4 library and the MPICH2 MPI library. Included in the intel.mk file are additional settings that can be modified during the build.
To run the default build (-O3 -msse2), go to the exec directory and enter the command
make
If you would like to change some of the compiler options, there are several different options to add to the make command. For example
make ISA=-xhost BLD_TYPE=REPRO
will replace -msse with -xhost and -O3 with -O2. The three options for
BLD_TYPE are
PROD (-O3)
REPRO (-O2)
DEBUG (-O0 and other traps)
All of the make line options can be
found in the intel.mk file.
The input data required for running the AM4 model can be found on GFDL's data portal .
The file AM4.tar.gz contains a configured run directory to run a
sample experiment of the AM4 model. Included in the tar file is a
README.AM4_run with more instructions on how to configure the AM4 run
directory.
On Linux systems, the wget command is usually sufficient to download the data
file:
wget ftp://nomads.gfdl.noaa.gov/users/Ming.Zhao/AM4Documentation/GFDL-AM4.0/inputData/AM4_run.tar.gz
To ensure the file downloaded is complete and not corrupted, download one of the two files:
wget ftp://nomads.gfdl.noaa.gov/users/Ming.Zhao/AM4Documentation/GFDL-AM4.0/inputData/AM4_run.tar.gz.sha256
wget ftp://nomads.gfdl.noaa.gov/users/Ming.Zhao/AM4Documentation/GFDL-AM4.0/inputData/AM4_run.tar.gz.sig
and run the following command that corresponds to the signature file downloaded:
sha256sum -c AM4_run.tar.gz.sha256
gpg --verify AM4_run.tar.gz.sig
Included in the run directory is a sample run script for reference. To run the AM4 sample experiment, first download the data file mentioned in Obtaining the Input data section. Modify the variables in the configuration section in the sample run script, and then run the script.
The sample data and run script are configured to run on 216
processors. To run on a different number of processors, or modify the
experiment, refer to the README.AM4_run file included in the AM4
data tarball.
Note: The input.nml file (found in the AM4 data tarball) contains
Fortran namelists and namelist variables that modify, at run time, the
model. To learn more about the settings in the input.nml file,
please refer to source code where the namelist/variable are defined.
Some of the climate analysis scripts run at NOAA GFDL and used in the AM4 documentation papers are located in the analysis directory. Within each analysis suite, is a jupyter notebook, both readable and runnable from your local jupyter environment, provided all dependencies are installed.
E.g.
- Radiation processor
- Long-term DJF seasonal mean
- Zonal_mean_zonal_wind_stress
- PCMDI Metrics Portrait Plot
Please refer to the AM4 data and code site for details about where to find model and OBS data used in the papers.
For all analysis figures and pertaining data, please use the AM4 documentation papers as the original reference.
Please direct your questions and feedback to gfdl.climate.model.info@noaa.gov
The United States Department of Commerce (DOC) GitHub project code is provided on an 'as is' basis and the user assumes responsibility for its use. DOC has relinquished control of the information and no longer has responsibility to protect the integrity, confidentiality, or availability of the information. Any claims against the Department of Commerce stemming from the use of its GitHub project will be governed by all applicable Federal law. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply their endorsement, recommendation or favoring by the Department of Commerce. The Department of Commerce seal and logo, or the seal and logo of a DOC bureau, shall not be used in any manner to imply endorsement of any commercial product or activity by DOC or the United States Government.
This project code is made available through GitHub but is managed by NOAA-GFDL at https://gitlab.gfdl.noaa.gov.