Fast and Robust Mesh Generation on the Sphere – Application to Coastal Domains. (2016)

• Record Type: Journal Article
• Authors: Remacle, Jean-François; Lambrechts, Jonathan
• Is Part Of: Procedia engineering. Volume 163(2016)
• Page Start: 20
• Page End: 32
• Publication Date: 2016
• Subjects: Delaunay triangulation on the sphere -- Geophysical flows -- Parallel meshing; Engineering -- Congresses; Engineering -- Periodicals; Engineering; Conference proceedings; Periodicals; 620.005
• DOI: 10.1016/j.proeng.2016.11.011
• Languages: English
• ISSNs: 1877-7058

Abstract

Abstract: This paper presents a fast and robust mesh generation procedure that is able to generate meshes of the earth system (ocean and continent) in matters of seconds. Our algorithm takes as input a standard shape-file i.e. geospatial vector data format for geographic information system (GIS) software. The input is initially coarsened in order to automatically remove unwanted channels that are under a desired resolution. A valid non-overlapping 1D mesh is then created on the sphere using the Euclidean coordinates system x, y, z . A modified Delaunay kernel is then proposed that enables to generate meshes on the sphere in a straightforward manner without parametrization. One of the main difficulty in dealing with geographical data is the over-sampled nature of coastline rep- resentations. We propose here an algorithm that automatically unrefines coastline data. Small features are automatically removed while always keeping a valid (non-overlapping) geometrical representation of the domain. A Delaunay refinement procedure is subsequently applied to the domain. The refinement scheme is also multi-threaded at a fine grain level, allowing to generate about a million points per second on 8 threads. Examples of meshes of the Baltic sea as well as of the global ocean are presented.