Issue

• Understanding, modeling, and predicting the effects of human activities on the environment requires long term data and information to provide for the needs of society.
• Complex environmental problems demand an integrated, multidisciplinary approach based on scientific data and information.
• Wise use of resources and development of effective strategies for adapting, mitigating, and responding to change depend on continued improvements in information, data availability, and data integration.

• USGS integrates many different kinds of data about the Earth's land surface.
• Records of human-induced phenomena, such as land use change, are crucial to understanding the ways that humans have transformed the landscape and the way the landscape functions. In the accompanying graphic, the red indicates urban growth in the San Francisco Bay area over the last 150 years while the green shows losses in tidal wetlands for the same period.
• Records of natural phenomena, such as earthquakes, are vital to protecting human health and safety; the yellow dots on each image indicate the location of earthquakes, magnitude 6.0 and above, occurring prior to the date of the image.
• USGS ensures these data and information derived from them are available to public and private organizations worldwide.
• USGS conducts scientific research in support of Federal policy and decision making.

• Federal agencies use the data and information to assess the condition of the environment; for example, to understand factors contributing to the loss of tidal wetlands.
• Public and private organizations depend on the data and information and integrated products to test their models of physical and human-influenced systems; for example, planning emergency response to earthquake events by integrating human settlement patterns with predictive earthquake models.
• Educators and the media use the data and information to teach earth and environmental science and inform the public; for example, the dynamic nature of urban land use in the San Francisco Bay area was demonstrated with an animation that caught the imaginations of residents of the Bay area.

Enlargements

• Click on any invidividual map above for an enlargement of that year
  • 1850 (283 KB)
  • 1900 (270 KB)
  • 1940 (299 KB)
  • 1990 (274 KB)
• Large version of the image above (448 KB)
• Poster-sized version of the image above (793 KB)