Surface and Volumetric Modeling for Digital Earth

地球幅员辽阔，蕴藏着丰富的有趣信息。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的数量和可变性的爆炸性增长，但许多公众仍然不知道或无法访问这些丰富的数据，以便就我们的星球做出明智的决定。为了促进对地球的深入了解，我们可以提供地球的数字模型(数字地球)，以便可以选择任何区域，并快速检索、分析和可视化与该区域相关的重要信息。选定的区域可以很小(例如高尔夫球场上的一个洞)、很大(例如地下水库)或很大(例如极地上空的大气)。这样的框架将帮助广大公众对地球和影响地球的问题做出决定。*为了创建数字地球，一种称为离散全球网格系统(DGGS)的几何建模方法应运而生。DGGS是一个参照系，它将地球离散成一系列高度规则的单元，每个单元都可以分配与该单元所代表的体积或面积有关的数据。为了支持多种空间分辨率，使用简单的细化对单元格进行分层细分。*这项研究的主要目标是调查各种全球网格的基本和几何方面，这些网格可以用来创建实用的数字地球系统。我们研究了开发3D体积DGGS、从大部分平面地理空间数据创建3D内容、将数字地球带入物理领域、在地图图标中可视化附加数据属性、开发和处理时变数据的问题。因此，作为一个拥有大量地理空间数据的幅员辽阔的国家，这一计划自然会让加拿大受益。此外，加拿大软件公司将受益于改进的数字地球技术和获得有才华的高素质人员。

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.