A new Digital Earth reference model: Spheroid-based 3D grid forEarth System (3DGES)

摘要

Being tightly related with map projection, planar mode cannot represent meso-scale and large-scale objects spanning projection zones and spheres, because map projection causes problems of with data fissure, geometry deformation and metric inaccuracy. Though Global Discrete Grid data model can solve these problems, it is only confined to the surface, it can not reach to the inside and outside of the surface. However, Spheoid Degenerated Octree Grid (SDOG) extend the extent to the whole spheroid space, and sets up a new spatial reference framework for 3D meso-scale to large-scale data model for Digital Earth and Earth System Science. It is able to represent geographical objects spanning projection zones and earth system objects spanning spheres, and able to be a substitution for the current data model. As for the property of multi-hierarchy, it can represent spatial objects in multi-resolution grids, with finer resolution grids used in more precise representation.