LFRic Orography (Projected)

This example demonstrates how to render a projected warped unstructured cubed-sphere mesh.

📋 Summary

Creates a mesh from 1-D latitude and longitude unstructured cell points.

The resulting mesh contains quad cells and is constructed from CF UGRID unstructured cell points and connectivity.

It uses an unstructured Met Office LFRic C48 cubed-sphere of surface altitude data.

Note that, the data is located on the mesh nodes/points which results in mesh interpolation across the cell faces. The point surface altitudes are used to extrude the mesh to reveal the global surface topography. Also, Natural Earth coastlines are rendered, and the mesh is transformed to the Equidistant Cylindrical (Plate Carrée) conformal cylindrical projection.

🏷 Tags: Projection Transform Mesh Unstructured Warp

---

Static Scene

Interactive Scene

from __future__ import annotations

import geovista as gv
from geovista.pantry.data import lfric_orog
import geovista.theme
from geovista.transform import transform_mesh


def main() -> None:
    """Plot a projected warped LFRic unstructured mesh.

    Notes
    -----
    .. versionadded:: 0.1.0

    """
    # Load the sample data.
    sample = lfric_orog()

    # Create the mesh from the sample data.
    mesh = gv.Transform.from_unstructured(
        sample.lons,
        sample.lats,
        connectivity=sample.connectivity,
        data=sample.data,
        name=sample.name,
    )

    # Transform the mesh to the Plate Carrée projection.
    mesh = transform_mesh(mesh, crs := "esri:54001")

    # Warp the mesh nodes by the surface altitude.
    mesh.compute_normals(cell_normals=False, point_normals=True, inplace=True)
    mesh.warp_by_scalar(scalars=sample.name, inplace=True, factor=200)

    # Plot the unstructured mesh.
    plotter = gv.GeoPlotter(crs=crs)
    sargs = {"title": f"{sample.name} / {sample.units}", "shadow": True}
    plotter.add_mesh(mesh, scalar_bar_args=sargs)
    plotter.add_axes()
    plotter.add_text(
        f"LFRic C48 Unstructured Cube-Sphere ({crs})",
        position="upper_left",
        font_size=10,
        shadow=True,
    )
    plotter.view_xy()
    plotter.camera.zoom(1.5)
    plotter.show()


if __name__ == "__main__":
    main()