🌍 Earth-System-Modelling

This repository contains the simple water balance model (SWBM) used in the Earth System Modelling course.
It is designed to demonstrate the most basic version of the model.

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✨ Features

• 🧹 Preprocessing of input data for the water balance model
• 💧 Simulation of soil moisture, runoff, and evapotranspiration
• ⏱ Easy-to-run time series simulations
• 📊 Correlation analysis between model output and observed data

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🗂 Input Data

The model requires an input CSV file with the following variables:

📅 time: Date or timestamp

🌐 latitude and longitude

☔ tp_[mm]: Precipitation in mm

☀️ snr_[MJ/m2]: Surface net radiation

Optional: (used for correlation with observations):

🌱 sm_[m3/m3]: Soil moisture

🌊 ro_[m]: Runoff

🔥 le_[W/m2]: Latent heat flux

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⚙️ Configuration

The model uses a configuration dictionary with these example parameters:

Parameter	Description	Example
c_s	Soil water holding capacity (mm)	420
a	Runoff function shape (α)	4
g	ET function shape (γ)	0.5
b0	Maximum of ET function (β)	0.8

Python example:

config = {
    'c_s': 420,
    'a': 4,
    'g': 0.5,
    'b0': 0.8
}

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🚀 Getting Started on your Local Machine

Follow these steps to set up the environment and run the model.

1. Install Git

If you do not have Git installed on your system, download and install Git for your system:

🌐 Git Downloads

2. Clone the Repository

git clone https://github.com/Motzemoere/Earth-System-Modelling.git
cd Earth-System-Modelling

4. Create and Activate an Environment

The easiest way is to use pip and a virtual environment:

# Install Python from https://www.python.org/downloads/ if not already installed
python -m venv esm
source esm/bin/activate  # on Windows: esm\Scripts\activate
pip install pandas numpy # install necessary packages

However I would recomend using conda:

Install Conda

If you do not have Conda installed, download and install Miniforge for your system:

🌐 Miniforge Releases

You should now have access to the Miniforge prompt command terminal

The easiest way is to just create the environment manually by runnning these commands in the miniforge prompt:

conda create -n esm python pandas numpy matplotlib -y
conda activate esm

4. 🏃Running the Model

Open the cloned repository folder in you prefered IDE, select the esm env as your Python interpreter and start playing around.

You can find a complete example workflow, including how to run the SWBM model, and compute correlations with observed data, in the following file:

➡️ swbm.py

There is also a R version of the model prvided:

➡️ swbm.r

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📬 Contact

If you have any questions, feel free to reach out:

✉️ mattis.pfenning@email.uni-freiburg.de

Reference

Koster, R. D., and S. P. P. Mahanama, 2012: Land surface controls on hydroclimatic means and variability. J. Hydrometeor., 13, 1604 1620, doi:10.1175/JHM-D-12-050.1.