Notes

Slide Show

Outline

1	Regional Geoid Improvements From Offshore Aerogravity Profiles Daniel R. Roman, John M. Brozena, and Yan M. Wang
2	Objective PRIMARY: To obtain and process gravity data that enhance the solution of a gravimetric geoid SECONDARY: Estimate the absolute error of U.S. vertical datum, NAVD 88 Estimate local SST conditions in the Bay of Maine
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5	Plot of intended Maine tracks
6	Processing Approach 20 km along track filter Crossover analysis for internal accuracy Upward continue gravity anomalies Comparison of observations & gravity anomalies at 7.6 km to establish external accuracy Remove EGM reference field at elevation Downward continue to surface and restore reference field Compare to gravity anomalies at the surface
7	Summary For regional gravimetric geoid models, adequate gravity data coverage is needed Augmentation of terrestrial, shipborne and altimeter-implied data by airborne profiles Internal and external analysis for accuracy Downward continue to geoid using R-C-R Compare to surface gravity anomalies to determine if the data are seamless from onshore to deep sea
8	Summary (cont.) Downward-continued aerogravity will improve near-shore geoid model Changes in the resulting gravimetic geoid can be verified at GPSBM locations Comparison with other gravity missions will highlight impact of elevation/speed Combining the littoral geoid with lidar-derived SST will yield estimates of the absolute accuracy of NAVD 88
9	Proposed Canadian Study