As we enter a discussion of geographic data licensing, it is necessary to be aware of the types of data now available. The purpose of this chapter is to classify geographic data to permit discussion of a broad range of geographic data types now available in the United States from a variety of sources, public and private. We broadly classify geographic data types by their origin, resulting from either processes of the natural world or human action. As any taxonomy, ours has fuzzy parts. We know that the physical and human worlds are intertwined and that human actions influence physical process and patterns. Nonetheless, a simple taxonomy allows for easy discussion of the various types of geographic data. We also associate federal agencies with particular types of geographic data, recognizing that agencies with parallel or overlapping functions at other government levels also use such data types.

Numerous features and variables are used to describe, visualize, analyze, and monitor Earth’s physical processes, patterns, and conditions. Of growing importance is the use of geographic data. In the United States, numerous government agencies and commercial firms participate in the acquisition and applications of geographic data. Below, we summarize features related to weather, hydrology, elevation, geology and physical geography, energy, and hazards that are available as geographic data.

Meteorological processes and weather influence biological and ecological systems, including the growth and health of species. Weather and climate also affect long-term geological and geomorphic processes and the physical geography of Earth’s surface. Table C-1 reports four weather features—precipitation, temperature, humidity, and winds—that often are presented as geographic data and used to assess current conditions and predict future ones. Federal agencies acquire and apply these geographic data. In addition, government agencies contract for commercial services related to data acquisition, and so, the private sector also is a stakeholder in these processes.