Digital Earth

Digital Earth is the name given to a concept by former US vice president Al Gore in 1998, describing a virtual representation of the Earth that is georeferenced and connected to the world's digital knowledge archives. Digital Earth is the name given to a concept by former US vice president Al Gore in 1998, describing a virtual representation of the Earth that is georeferenced and connected to the world's digital knowledge archives. In a speech prepared for the California Science Center in Los Angeles on January 31, 1998, Gore described a digital future where schoolchildren - indeed all the world's citizens - could interact with a computer-generated three-dimensional spinning virtual globe and access vast amounts of scientific and cultural information to help them understand the Earth and its human activities. The greater part of this knowledge store would be free to all via the Internet, however a commercial marketplace of related products and services was envisioned to co-exist, in part in order to support the expensive infrastructure such a system would require. The origin of the idea can be traced back to Buckminster Fuller's Geoscope, a large spherical display to represent geographic phenomena. Many aspects of his proposal have been realized - for instance, virtual globe geo-browsers such as NASA World Wind, Google Earth and Microsoft's Bing Maps 3D for commercial, social and scientific applications. But the Gore speech outlined a truly global, collaborative linking of systems that has yet to happen. That vision has been continually interpreted and defined by the growing global community of interest described below. The Digital Earth imagined in the speech has been defined as an 'organizing vision' to steer scientists and technologists towards a shared goal, promising substantial advances in many scientific and engineering areas, similar to the Information superhighway. Two noteworthy excerpts from the Beijing Declaration on Digital Earth, ratified September 12, 2009 at the 6th International Symposium on Digital Earth in Beijing: A group of international geographic and environmental scientists from government, industry, and academia brought together by the Vespucci Initiative for the Advancement of Geographic Information Science, and the Joint Research Centre of the European Commission recently published 'Next-Generation Digital Earth' a position paper that suggests its eight key elements: Significant progress towards Digital Earth has been achieved over the last decade as collected in a survey paper by Mahdavi-Amiri et al., including work in these categories: The number of Spatial Data Infrastructures has grown steadily since the early 1990s, aided in part by interoperability standards maintained by the Open Geospatial Consortium and the International Organization for Standardization (ISO). Significant recent efforts to link and coordinate SDI's include Infrastructure for Spatial Information in Europe (INSPIRE) and the UNSDI Initiative of the UN Geographic Information Working Group (UNIGWG). Between 1998 and 2001, the NASA-chaired Interagency Digital Earth Working Group (IDEW) contributed to this growth with a particular focus on interoperability issues, giving rise to the Web Map Service standard among others. The scientific use of geo-browser virtual globes such as Google Earth, NASA's World Wind, and ESRI's ArcGIS Explorer has grown significantly as their functionality has improved and with the KML format having become the de facto standard for globe visualizations. Numerous examples can be viewed at the Google Earth Outreach Showcase and at the World Wind Java Demo Applications and Applets. Geosensors are defined as '...any device receiving and measuring environmental stimuli that can be geographically referenced.' Large scale networks of geosensors have been in place for many years, measuring Earth surface, hydrological and atmospheric phenomena. The advent of the Internet led to a large expansion of such networks, and efforts like Global Earth Observation System of Systems (GEOSS) Initiative aim to connect them.