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GeMS Validation Survey

May 12, 2022  |  2:00-3:00 pm, ET

Presenter: Kevin Ahlgren, Geodesist, Observations and Analysis Division, NGS

In the Fall of 2021, NGS performed a field campaign in south-central Alaska to obtain geodetic observations that will be used by the Geoid Monitoring Service (GeMS) to validate time-dependent geopotential models (geoid, gravity, deflection of the vertical). The observations collected are critical to GeMS and a time-dependent geoid model in order to evaluate two situations: 1) to assess how much geoid change has occurred since 1964, when the Coast and Geodetic Survey performed a very high-accuracy triangulation, leveling, and gravity survey following the 1964 Alaska Earthquake; and 2) to establish a baseline to measure all subsequent geoid change against in the future.

*Technical Content Rating: Intermediate - Some prior knowledge of this topic is helpful.