A Global " Natural" Grid Modeling Method Based on Terrain Topological Structure
In this paper, a Global " Natural" Grid (GNG) modeling method based on the terrain topological structure is proposed. GNG partitions the earth surface into " natural" cells by using the natural terrain feature elements, which may be more suitable for exploring and understanding some natural phenomena in the environment monitoring, hydrological analysis, species distribution, etc. This modeling method mainly consists of three steps: firstly, a variable-resolution geometric representation of global DEMs based on the restricted quadtree is constructed; secondly, the feature elements are extracted and an original GNG model is built; finally, a multi-resolution representation of GNG is established by recursively applying topological simplification. In the end, an experiment is done to validate the correctness and feasibility of this modeling method.