Framework of Twin Virtual Geographic Environment

Virtual geographic environment (VGE) has experienced a more than 20-year development, which evolved from an idea to an independent geographic research field. The theoretical system of VGE has gone through a leap from theory to practice, from simple application to a large-scale engineering project. Now it has become an essential tool for studying geographic issues and is going towards geographic cognition. With the development of big data, VR technology, 5G technology, artificial intelligence technology, digital twin technology and metaverse, VGE as a platform for geographic scientific research is becoming more and more powerful. Still, the present VGE cannot reach the real-time and simulation requirements. To maintain the advancement of the theory of virtual geographic environment in the age of ever-changing technology, a new framework of twin virtual geographic environment (TVGE) has been proposed to support the sustainable development of the VGE theoretical system. In this context, we elaborate the TVGE framework, including definition, reasoning, characteristics, version management, and geographic cognition, which updates the VGE theory with the emerging technologies and lays the foundation for the VGE platform implementations.