Surface and Volumetric Modeling for Digital Earth

地球是巨大的，充满了有趣的信息。地理空间传感器（如卫星、智能手机、气象仪器和激光雷达）的最新进展导致了能够收集大量动态地理空间数据的技术的发展。因此，我们正在经历地理空间数据量和可变性的爆炸式增长，然而，许多公众仍然不知道或无法访问这些丰富的数据，以对我们的星球做出明智的决定。为了加深对地球的了解，我们可以提供地球的数字模型（数字地球），这样可以选择任何区域，并快速检索、分析和可视化与该区域相关的重要信息。所选区域可以很小（例如高尔夫球场上的一个洞），也可以很大（例如地下水库），或者很大（例如极地上空的大气）。这样一个框架将有助于广大公众对地球和影响地球的问题作出决定。

The Earth is immense, and abundant with interesting information. Recent advancements in geospatial sensors (e.g. satellites, smart phones, meteorological instruments, and LIDAR) have resulted in the development of technologies capable of collecting large and dynamic geospatial data. As a result, we are experiencing an explosion in the volume and variability of geospatial data, and yet many in public remain unaware of or unable to access this wealth of data to make informed decisions regarding our planet. To foster a strong understanding of the Earth, we may offer a digital model of the Earth (a Digital Earth) such that any region may be selected and important information related to that area rapidly retrieved, analyzed, and visualized. The selected area can be small (e.g. a hole in a golf course), large (e.g. an underground reservoir), or huge (e.g. the atmosphere above polar regions). Such a framework will help the public at large to make decisions about the Earth and the issues affecting it. To create Digital Earth, a geometric modeling approach has emerged called the Discrete Global Grid System (DGGS). A DGGS is a reference system that discretizes the Earth into a series of highly regular cells, each of which can be assigned data pertaining to the volume or area represented by the cell. To support multiple spatial resolutions, cells are hierarchically subdivided using simple refinements. The main objective of this research is to investigate the fundamental and geometric aspects of various global grids that may be used to create practical Digital Earth systems. We examine the problems of developing a 3D volumetric DGGS, creating 3D content from mostly flat geospatial data, bringing a Digital Earth to the physical realm, visualizing additional data attributes in map icons, developing, and dealing with time-varying data. Therefore, this program will naturally benefit Canada as a vast country with a large volume of geospatial data. Furthermore, Canadian software companies will benefit from improved Digital Earth techniques and access to talented highly qualified personnel.