Defining a digital earth system

In a 1998 speech before the California Science Center in Los Angeles, then US Vice-President Al Gore called for a global undertaking to build a multi-faceted computing system for education and research, which he termed "Digital Earth." The vision was that of a system providing access to what is known about the planet and its inhabitants'activities -currently and for any time in history -via responses to queries and exploratory tools. Furthermore, it would accommodate modeling extensions for predicting future conditions. Organized efforts towards realizing that vision have diminished significantly since 2001, but progress on key requisites has been made. As the 10 year anniversary of that influential speech approaches, we re-examine it from the perspective of a systematic software design process and find the envisioned system to be in many respects inclusive of concepts of distributed geolibraries and digital atlases. A preliminary definition for a particular digital earth system as: "a comprehensive, distributed geographic information and knowledge organization system," is offered and discussed. We suggest that resumption of earlier design and focused research efforts can and should be undertaken, and may prove a worthwhile "Grand Challenge" for the GIScience community.