“…While maps and globes have been used to depict geography for thousands of years, new ubiquitous multi-spectral sensing methods based on satellite imagery and pictures taken by unmanned aerial vehicles, often combined with Internet-of-Things and crowd-sourced data, 12 have elevated the field to entirely new levels of detail. 13 Compared to the systems discussed in the next sections, these applications of digital twins are relatively simple for the following reasons:…”