This is an implementation of the Rainfall Model in Python, using Mesa and Mesa-Geo. Inspired by the NetLogo Grand Canyon model, this is an example of how a digital elevation model (DEM) can be used to create an artificial world.
The GeoSpace contains a raster layer representing elevations. It is this elevation value that impacts how the raindrops move over the terrain. Apart from elevation, each cell of the raster layer also has a water_level attribute that is used to track the amount of water it contains.
In this example, the raindrops are the GeoAgents. At each time step, raindrops are randomly created across the landscape to simulate rainfall. The raindrops flow from cells of higher elevation to lower elevation based on their eight surrounding cells (i.e., Moore neighbourhood). The raindrop also has its own height, which allows them to accumulate, gain height and flow if they are trapped at places such as potholes, pools, or depressions. When they reach the boundary of the GeoSpace, they are removed from the model as outflow.
To run the model interactively, run solara run app.py in this directory. e.g.
solara run app.pyThen open your browser to http://127.0.0.1:8765/ and press the play button ▶.
The data is from the Rainfall Model and is licensed under the Creative Commons Attribution-ShareAlike 4.0 International License.