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Regional Models

South America (GEOID2015)

  Authors: D. Blitzkow, et al.     Created: 2015    Resp: A.C.O.C. de Matos  
      Status: PUBLIC    
The new South America geoid model has been computed on a 5' x 5' grid, by the remove-compute-restore technique using 947,953 point gravity data (free-air gravity anomalies), the SAM3s_v2 DTM for the computation of terrain correction and other topographic and atmospheric effects. The mean free-air gravity anomaly (FA) in a 5' grid over continent was derived from the complete BA (FA over the ocean obtained from satellite altimetry model DTU10). The short wavelength component was estimated with FFT technique using the modified Stokes integral through spheroidal Molodenskii-Meissl kernel modification. The reference field used was EIGEN-6C4 up to degree and order 200. The computed points are in a grid of 5' x 5' covering the area from 56.9583333° S to 14.9583333° N in latitude, and from 94.9583333° W to 30.0416667° W in longitude. The geoidal heights are referred to WGS84. Data are stored in grd format, i.e. parallelwise from N to S and W to E. (N° values in lat = 864, N° values in long = 780, total number of data = 673920).
D. Blitzkow, A.C.O.C. de Matos, G. do Nascimento Guimaraes, M.C. Pacino, E.A. Lauria, M. Nunes, C.A. Correia e Castro Junior; F. Flores, N.O. Guevara, R. Alvarez, J.N. Hernandez (2016). Gravity and geoid model for South America
. EGU General Assembly 2016, Geophysical Research Abstracts, Vol. 18, EGU2016-1626.

South America