LOCATING GEOSCIENCE DATA AND TOOLS THROUGH NASA'S GLOBAL CHANGE MASTER DIRECTORY

NASA's Global Change Master Directory (GCMD) enables researchers, educators and students to discover and access information on nearly 15,000 Earth science data sets and services. The GCMD covers a broad range of Earth science disciplines, with nearly 18% of the database holdings directly relevant to geoscience disciplines such as geochemistry, geomagnetism, seismology, tectonics, and volcanoes. Other geoscience disciplines include marine geophysics, land surface processes, hydrology and space weather. Geologic time periods can be specified as dates BP (or ybp or kya) and/or as chronostratigraphic units (Quaternary, Permian, Cambrian, etc.).

The GCMD also offers over 900 descriptions of Earth science tools, resources, and services. Users can search for tools by selecting keywords from the following categories: data management/data handling, hazards management, metadata handling,information services, data analysis and visualization tools, models, Earth science educational resources, and environmental advisory services. The last four topics contain the majority of the geoscience tools and services. Some examples of geological time period tools are "Global Paleogeographic Views of Earth History – Late Precambrian to Recent" and "Regional Paleogeographic Views of Earth History". Both of these are educational resources and data analysis and visualization tools. The GCMD provides direct links to tools and services from the data set descriptions, and, where possible, links to data sets that can be used with the tools. The GCMD homepage is http://gcmd.nasa.gov.