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Regional Models

Northwest Pacific Ocean

  Authors: A.B. Watts, A.R. Leeds     Created: 1976    Resp: A.B. Watts  
      Status: PUBLIC    
This is a gravimetric geoid the Northwest Pacific Ocean, covering the area 1° < lat < 65°, 106° < lon < 210° with a grid spacing of 1°x1°. It is based on a compilation of 147000 surface ship and pendulum gravity measurements, from which 1°x1° gravity anomaly averages are derived. The gravimetric geoid is computed by Stokes's integration in the framework of a remove-restore procedure with the GEM-6 global gravity model as reference field. The rms of the differences between this gravimetric geoid and contemporary satellite derived models (SE-3, GEM-6 and GEM-8) is about 6 m. In particular, difference geoid undulations range from a maximum of +19 m over the Hawaiian ridge to a minimum of −31 m over the junction of the Kuril and Aleutian trenches. The agreement between this gravimetric geoid and Skylab-4 and Geos-3 altimeter data is close for wavelengths greater than about 300 km but poor for shorter wavelengths.

A.B. Watts, A.R. Leeds (1977). Gravimetric geoid in the Northwest Pacific Ocean. Geophysical Journal International, 50(2), pp. 249-277.