On our ever-changing Earth, conditions may change quickly or slowly. Some changes come from natural processes; some from human activity. Satellites allow us to see conditions and track changes over time — in land use, forest health, land/water interface, and so on. Since 1972, Landsat satellites have been collecting data using various portions of the visible and invisible electromagnetic spectrum, at a scale close enough to see highways, but not individual buildings on a city block.
An EarthCache is a special site that people can visit to learn about a unique geoscience feature or aspect of our Earth. Visitors to EarthCache sites can see how our planet has been shaped by geological processes, how we manage the resources and how scientists gather evidence to learn about the Earth.
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