World Cities and Google Earth

Google Earth is an online 3D virtual globe draped with high quality satellite and areal imagery of the Earth’s surface that empowers users to zoom down onto major cities, into the hustle and bustle of their busy street and even gives us the opportunity to witness the evolution of such cities over time.

Thanks to the addition of the timeline feature, it is now possible to study, analyze and track the changes that ocurred in major metropolitan cities such as Paris or London all the way back to the early 20^th century. The integration of old military aerial maps and city blue prints over which one can view modern 3D buildings provides a great tool for studying urban planning in different countries and over time periods. In general, the timeline feature is best to track the evolution of short run structural changes. One example is the availability of imagery tracking the evolution of the Beijing Olympic Stadium over its construction.

For historical enthusiasts or simply for the curious, the use of the Rumsey’s historical maps layer directly integrated within the software allows users to study how cities such as Tokyo or Beijing have changed over longer periods of time by contrasting 15^th century military maps with more recent colonial maps and then with up to date and accurate satellite and aerial imagery.

Furthermore, more focused layers such as Rome 3D empower users to gain knowledge on the ancient structures of the city, most of which are superposed and built one over the other. In Rome’s case it is particularly interesting as the evolution of the city cannot simply be understood through 2 dimensional maps as over different periods, monuments and important structures have been built one over the other. Only written records exist to testify of their existence and particular shape, size and location. Therefore Rome 3D offers a great tool that recreates graphic imagery of structures that would be otherwise impossible to view without the use of historical data. It gives users a better understanding of the evolution of the city over the ages.

Finally, the Street View option, now available for most metropolitan areas, allows users to get at an up close and personal level and view the current state of shops, roads and highways and other infrastructures.