EXPLORING EARTH'S SURFACE WITH COMMUNITY MODELS: THE CSDMS PYTHON MODELING TOOL

Our planet’s surface is a restless place. Understanding the processes of weathering, erosion, and deposition that shape it is critical for applications ranging from short-term hazard analysis to long-term sedimentary stratigraphy and landscape/seascape evolution. Improved understanding requires computational models, which link process mechanics and chemistry to the observable geologic and geomorphic record. Historically, earth-surface process models have often been complex and difficult to work with. To help improve this situation and make the discovery process more efficient, the CSDMS Python Modeling Tool (PyMT) provides an environment in which community-built numerical models and tools can be initialized and run directly from a Python command line or Jupyter notebook. By equipping each model with a standardized set of command functions, known collectively as the Basic Model Interface (BMI), the task of learning and applying models becomes much easier. Using BMI functions, models can also be coupled together to explore dynamic feedbacks among different earth systems. To illustrate how PyMT works and the advantages it provides, we present an example that couples a terrestrial landscape evolution model (CHILD) with a marine sediment transport and stratigraphy model (SedFlux3D). Experiments with the resulting coupled model provide insights into how terrestrial “signals,” such as variations in mean precipitation, are recorded in deltaic stratigraphy. The example also illustrates the utility of PyMT’s tools, such as the ability to map variables between a regular rectilinear grid and an irregular triangulated grid. By simplifying the process of learning, operating, and coupling models, PyMT frees researchers to focus on exploring ideas, testing hypotheses, and comparing models with data.