Measuring the World
Why Elevation Follows Gravity: The Geoid Beneath Every Height
GNSS measures height above a mathematical ellipsoid, but practical elevation depends on gravity, the geoid, and a physical definition…
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When Coordinates Expire: Surveying on a Moving Continent
Precise coordinates are tied to both a reference frame and a date because tectonic plates, earthquakes, subsidence, and other deformation keep the ground in motion.
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Maps & Mapping
Surveying Beneath Ice: Mapping Continents Hidden From View
Airborne radar, satellite altimetry, GNSS, gravity, and decades of field surveys reveal the mountains, canyons, lakes, and basins concealed…
Nature & Landscapes
Reading Motion in Radar Fringes: How InSAR Maps a Changing Ground
By comparing the phase of repeated radar observations, InSAR can reveal earthquake deformation, volcanic inflation, subsidence, and other surface…
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