The Brazilian geoid model MAPGEO2010 is limited by 6°N and 35°S in latitude and 30°W and 75°W in longitude with a 5' resolution. The terrestrial gravity data for the continent have been updated by surveys in Brazil and in the neighbour countries until 2010. The complete Bouguer and Helmert gravity anomalies have been derived through the Canadian package SHGEO. The short wavelength component was estimated via FFT. The geopotential model EGM2008 was used as a reference field restricted to degree and order 150. The geoid height was corrected from the zero-order term, -0.41 meter, for compatibility with the GRS80 ellipsoid, used by SIRGAS2000. The RMS difference associated with the MAPGEO2010 model was ±0.28 meter, determined from the comparison of IBGE GPS/levelling points.
The geoid model is provided in ISG format 2.0 (ISG Format Specifications), while the file in its original data format is available at the model ISG webpage.
The International Service for the Geoid (ISG) was founded in 1992 (as International Geoid Service - IGeS) and it is now an official service of the International Association of Geodesy (IAG), under the umbrella of the International Gravity Field Service (IGFS). The main activities of ISG consist in collecting, analysing and redistributing local and regional geoid models, as well as organizing international schools on the geoid determination.