Hello from Josh

Josh is a friendly programming language co-designed by research software engineers, ecologists, mathematicians, and land managers for vegetation-focused ecological modeling. This short tutorial introduces you to the basics of Josh. Here, you can try out a simulation on your computer using just your browser.

Try it yourself

Now that we have built up the simulation, give it a run yourself. This will execute on your computer in your browser. Make modifications to the code and then click the run button.

Configuration

Change these values and click Run to see how drought limits and the yearly growth cap reshape the forest.

Climate inputs driving this simulation

Map of input temperature in Kelvin across the simulation grid, warmer to the south

Temperature growth response: a quadratic curve peaking near 300 K and zero outside 270 to 330 K

Map of input precipitation in millimeters per year across the grid, wetter to the west

Precipitation growth response: a sigmoid rising with precipitation between 300 and 500 mm

Compare the height map above against these inputs: warmer mid-range and wetter patches should grow taller.

Next steps

You have just run a real ecological simulation — entirely in your browser. To go further, visit the full Josh guide where you can explore more simulations, work with real geospatial data, and run Josh on your own machine.