Feasibility of Using Satellite Altimetry to Validate or Enhance the International Great Lakes Datum

Session: A Possible New Paradigm to Improve the International Great Lakes Datum and Its Maintenance (1)

C K Shum, Dvision of Geodetic Science, School of Earth Sciences, The Ohio State University, [email protected]
Josef Sebera, Astronomical Institute, Academy of Sciences of the Czech Republic, [email protected]
Aleš Bezd?k, Astronomical Institute, Academy of Sciences of the Czech Republic, [email protected]
Chaoyang Zhang, Divison of Geodetic Science, School of Earth Sciences, Ohio State University, [email protected]
Jason Otero Torres, Division of Geodetic Science, School of Earth Sciences, Ohio State University, [email protected]
Philip Chu, NOAA/GLERL, [email protected]
Junyi Guo, Division of Geodetic Science, School of Earth Sciences, Ohio State University, [email protected]
Yuanyuan Jia, The Ohio State University, [email protected]

Abstract

The Great Lakes are comprised of the largest freshwater bodies on Earth and supplies over 34 million people in the US and Canada for water resources, food, recreation, farming, hydraulic/nuclear power, and safe navigation. Modernizing the height datum and updating the International Great Lakes Datum (IGLD) by 2020 enhances the aforementioned benefits to the Great Lakes citizens and complements the Great Lakes Observing System, CoastWatch, and assimilative Lake forecasting, including NOAA’s GLCFS, GLOFS, NGGPS, and NWM. IGLD update is to be accomplished by the National Geospatial Reference System, North American/Pacific Geopotential Datum of 2022(NAPGD2022), and (global) GEOID2020 model, currently under development using airborne gravity and other data sets including satellite gravity data. In the Great Lakes, Dynamic Heights will be used instead of orthometric height to realize the IGLD.  Here, we will test the hypothesis that more than two decades of satellite altimetry over the Great Lakes from CoastWatch would provide independent gravity or deflection of vertical measurements, either as a IGLD validation dataset, or perhaps to be included for global geopotential solution in terms of ellipsoidal and spherical harmonics, complete to degrees around 4,000, and potentially with a spatial resolution of 5 km half-wavelength over the Great Lakes region.