OxyPOM and DiaMO: simple models for dissolved oxygen and biogeochemistry

OxyPOM (Oxygen and Particulate Organic Matter) and DiaMO (Diagnostic Model for Oxygen) are aquatic biogeochemical models that consider key processes for dissolved oxygen (DO), such as re-aeration, mineralization, and primary production, in fresh, transitional and marine waters. Both are implemented in the Fortran-based Framework for Aquatic Biogeochemical Models (FABM) for interoperability in a variety of hydrodynamic models, in realistic and idealized applications, and for coupleability to other aquatic process models.

Description

• OxyPOM simulates oxygen consumption and production in aquatic ecosystems (Holzwarth and Wirtz, 2018) and resolves key biogeochemical processes as photosynthesis, respiration, mineralization, and nitrification.

• DiaMO is a simplification of OxyPOM useful when a complete representation of bio-geochemical dynamics is not needed,

The code of these models is located in the directory ./src (e.g., ./src/oxypom and ./src/diamo), and future code developed as part of this model should be here included.

Together with OxyPOM and DiaMO, this repository includes the model oxypom/light: a second order correction for the calculation of photosynthetically active radiation depth profiles.

Requirements

• This model requires:

  • FABM (v1 or above) available in fabm github. It can be cloned using git clone https://github.com/fabm-model/fabm.git fabm.

• The physical driver:

  • GOTM (v6.0 latest stable release) available in gotm github. It can be cloned using via git clone --recursive https://github.com/gotm-model/code.git -b v6.0 gotm6.

The following is not required to build and run the model but it is for running the test case:

• The script for downloading forcing and validation data requires the shell commands wget, unzip, and sed.

• The scripts for generating forcing files setup and plotting routines for model validation require R (v4.3 or above) available in r home with the library ncdf4 installed.

Testcases

We provide the model with a testcase in the directory ./testcases. New testcases for OxyPOM and DiaMO should be included in a single directory within ./testcases. Currently, we include the testcase "Estuary".

Testcase Estuary

This setup uses the physical driver GOTM to simulate the water column dynamics in the Elbe estuary in 2005-2024.

1. To run the testcase go to the directory ./testcases.

The model is build with the script gotm-installation.sh, in where these variables must be defined: - GOTM_DIR base directory of GOTM source code - FABM_DIR base directory of FABM source code - OXYPOM_DIR base directory of OxyPOM source code

By default they are:

``` bash
export GOTM_DIR=$HOME/tools/gotm6
export FABM_DIR=$HOME/tools/fabm/fabm
export OXYPOM_DIR=$HOME/tools/oxypom/src
```

2. The script gotm-installation.sh creates the directory ./build with the building files, and a copy of gotm executable in the ./estuary directory. Now move to the directory ./estuary.

3. The script get_data.sh download and unzip the forcing and validation data from kuestendaten.de in a newly created directory ./data. The downloaded files are used under license DL-DE->Zero-2.0.

4. The script setup_data.R formatted the data to be read by GOTM. It generates the file meteofile.csv.

5. Run the model with ./gotm. It generates the files output.nc and restart.nc.

6. The script plot_output.R analyses the model output.

If everything is correct, the figure estuary_validation.png should be produced. It displays a comparison of simulation and data for temperature and dissolved oxygen values.

The entire procedure is included in ./testcases/run-estuary-testcase.sh.

Testcase light

This setup uses the physical driver GOTM to simulate the water column dynamics in the Elbe estuary in 2005-2024 and compares the default light implementation with the provided by oxypom/light.

Follow steps 1-2 of the estuary testcase.

Now move to the directory ./light.

• The script model_comparison.R analyses the model output.

If everything is correct, the figure light_validation.png should be produced. It displays a comparison of simulations using the default light implementation with the provided by oxypom/light.

The entire procedure is included in ./testcases/run-light-testcase.sh.

License

Apache-2.0 (OxyPOM and DiaMo)

Project status

This is part of the DAM-ElbeXtreme project.

Contributing and reporting

We recommend to use latest git commit an branch main version of the model. We appreciate your feedback, bug reports and improvement suggestions on our GitLab issue tracker. We also welcome your contributions, subject to our Contributor Covenant code of conduct and our Contributor License Agreement.

The best way to contribute is by (1) creating a fork off our repository, (2) committing your changes on your fork and then (3) creating a pull request ("PR") to push your changes back to us.

To file an issue or to contribute, you are asked to (1) authenticate with an existing identity and (2) to register on the HIFIS GitLab instance and sign in. When asked, click "Sign in with Helmholtz AAI". On the following page "Login to Helmholtz AAI OAuth2 Authorization Server", search for one of your existing authentication providers (this may be your university, company, ORCID, GitHub, or many others) and provide their login credentials for authorization. If you are not already registered on the HIFIS GitLab instance, a confirmation email will be sent to the primary email address registered with your authentication provider. After clicking the confirmation link, you will also be asked to provide a name on this GitLab instance; this will be your nickname. Help on this one-time registration process is available from https://hifis.net/tutorial/2021/06/23/how-to-helmholtz-aai.html.