CIESIN Thematic Guides

The Potential of Satellite Remote Sensing for Human Dimensions of Global Environmental Change Program Activities and Research

The consistent, continuous land coverage provided by satellite image data has the potential to contribute land-cover and land-use change information to several Human Dimensions of Global Environmental Change Program (HDP) activities and developing research initiatives.

The HDP Working Group on Demographic Data identify and assess the manifold data about population in their report Population Data and Global Environmental Change (Clarke and Rhind 1992). The report recommends that, to be useful in global change research, georeferenced population data should be developed for at least three levels of application. The first two levels consist, respectively, of national level data, which generally exist but are not always available and not georeferenced in any consistent manner, and rectangular area data from the U.S. Bureau of Census Center for International Research, which have not been readily available to researchers. The Consortium for International Earth Science Information Network (CIESIN) is exploring ways to make both these levels of data available on a global basis. The third recommended level is for a high-resolution data set at the spatial resolution of 1 km or better to have population figures at the commune or even finer resolution level. The report recommends that satellite image data be investigated for creating such a high-resolution data set, using demographic data gathered by conventional means as a control.

The SysTem for Analysis Research and Training (START) Program , a joint activity for the International Geosphere-Biosphere Program (IGBP), the World Climate Research Program (WCRP), and the Human Dimensions of Global Environmental Change Programme (HDP), is devoted to assisting regional groups of developing countries in establishing global change regional research networks. The HDP has begun working within START to convene groups of social scientists from each of the regions to identify priority topics in the study of the human dimensions of global environmental change and to relate these to the emerging natural science research priorities. Although specific approaches and topics in each region differ, social scientists have begun to focus attention on land cover, its responses to the driving forces of land-use change, and its impacts on future land-use practices. Satellite remote sensors provide global image coverage that could offer comprehensive land-cover and land-use change information for all regional research networks.

The Global Omnibus Environmental Survey (GOES) initiative has evolved out of recommendations of two HDP Working Groups: the Perception and Assessment of Global Environmental Change group and the Survey Research Data group. Essentially, the purpose of GOES is to develop and administer a survey form for gathering baseline data worldwide on environmental knowledge, attitudes, and behaviors. Periodic re-surveys would provide for regular monitoring of peoples' understanding of global environmental change and activities related to it. A proposed research design for the GOES survey currently calls for a core survey, specialized modules focused on science and public policy issues, and contextual data. All three elements require stratification by geophysical location and type of land use. Satellite image data could be a valuable tool in assisting such stratification.

An IGBP-HDP Ad-Hoc Working Group has proposed a joint IGBP-HDP Core Project to investigate Land Use and Global Land Cover Change, as described by Turner, Moss, and Skole (1993) in "Relating Land Use and Global Land-Cover Change." Land-use change has been identified as a priority human dimensions issue because of the increased awareness of its role as a major driver of environmental change. Human dimensions research will have requirements for land-use information that includes the forms of land-cover change, the patterns of change, and the rates of change as influenced by the driving forces of human actions. Current global aggregations of land use/land cover change are subject to debate, because they are based on imprecise measurements or on estimates. Global aggregate relationships to driving forces often mask the increased complexities of human actions at the subglobal scale.

The joint IGBP-HDP project will address the dynamics of land-use and land-cover change by developing a typology for the relationships among human driving forces, land-use change processes, and resulting land cover. These "situational assessments" will be defined at subglobal levels to develop regionally sensitive relationships, and then tested through systematic case studies that use and collect common data to answer standard questions about the influence of socioeconomic context on land cover change. Regional models will be globally integrated to enable understanding and projection of global-scale land-cover change. Some of the data and information needs satellite image data could help provide include stratified land-cover characteristics in current time, stratified rates of change, and proximate sources of change.