What SEALS is
SEALS, the Spatial Economic Allocation Landscape Simulator, is a land-use change model that downscales predictions of land-use change from aggregate (regional or coarse-gridded) inputs to a finer resolution, typically 10–300 meters.
Its primary comparative advantage is fast computation. It downscales to 300 meters globally — roughly 8.4 billion grid cells — in about an hour on a laptop. It is designed with parallelization in mind and so scales well to high-performance, cloud, or distributed computing. Performance-critical functions are written in C++ (via Cython); everything else is Python.
SEALS is one of three software products maintained by NatCap TEEMs (The Earth-Economy Modellers):
| product | what it is |
|---|---|
| SEALS | this model — the downscaler |
| GTAP-InVEST | the coupled economy–ecosystem model that uses SEALS for its land-use step |
| Earth-Economy Devstack | the shared platform: hazelbean, ProjectFlow, and the conventions all three follow |
How to read this guide
Start at Environment Setup and Quickstart — together they take you from nothing to a downscaled map. Then:
- Walkthrough — a guided first run, and the anatomy of a run file. Read this before you start a project of your own.
- scenarios.csv format — the column reference for the file that defines what SEALS runs.
- MAgPIE and the MAgPIE tutorial — coupling SEALS to an external land-use model, which is also the general pattern for coupling it to any coarse projection source.
This guide is rendered both as a website and as a single PDF (download). If you are reading the PDF, links to the other two products point at the published site.
Where SEALS ends and the platform begins
SEALS is a model. The machinery that runs it — project directories, task trees, skip-if-already-computed re-runs, automatic base-data download — is ProjectFlow, which lives in hazelbean and is shared across all three products. This guide covers SEALS and says only as much about ProjectFlow as you need to run it.
For the platform itself, see the Earth-Economy Devstack documentation:
- Conventions — the run-file spec, naming rules, and directory layout
- Project complexity — the three axes that describe how a run file is organized, and why
- ProjectFlow — the task-tree engine
- Installation — devstack-wide install options, including the developer install
Status and citation
SEALS is under active development and changes rapidly. Pull the latest seals_dev before reporting a problem.
The model was introduced alongside GTAP-InVEST in Johnson et al. 2023, PNAS. All code is available under a permissive open-source license.