CIESIN Thematic Guides

Uses of Satellite Image Data for Assisting Human Dimensions Studies of Global Environmental Change

In the broadest context, satellite image data can be considered to provide two major uses for assisting human dimensions studies. The first use is as a spatial frame of reference for assisting the planning and coordination of global change research. The second use is as a basis for information derivation through data processing and analytic procedures employed as part of the research methodology. The general distinction made here between these two uses is for the benefit of discussion; in practice the distinction is frequently blurred in the course of the research process.

Use of satellite image data as a spatial frame of reference generally refers to the use of image products that have been prepared to enhance the visual distinction of all, or selected, landscape features. Satellite image products can assist the planning and coordination of global change research by facilitating the design of research strategies and the implementation of methodologies that contribute to a global understanding of human dimensions activities. For strategizing at the global scale, satellite images provide Global Context Information. For implementing studies at local and regional scales, satellite images provide a consistent basis for promoting Uniform Research Methods. For presenting the results of human dimensions studies, satellite images enable the development of useful Knowledge Transfer Products.

Satellite image data offer significant capabilities for deriving information integral to human dimensions studies, especially those concerned with the impacts of human activity on land use and land cover. These data inherently contain information that relates to the type and spatial extent of land cover. Major techniques for deriving information from satellite images include 1) Image Interpretation; 2) Digital Image Classification; 3) Data Transformations; and 4) Change Detection. The information output of these operations may be useful as a final product or can be entered into a geographic information system (GIS) for subsequent integrated analysis and/or model development with other spatial variables.