An evaluation of recent GOCE geopotential models in Brazil

Autor(es)

Guimaraes, G. N. ; Matos, A. C. O. C. ; Blitzkow, D.

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF GEODETIC SCIENCE; v. 2, n. 2, p. 12-pg., 2012-06-01.

Resumo

Several global geopotential models based on Gravity field and steady-state Ocean Circulation Explorer (GOCE) data have been published in the last two years. Some of these models use combinations of different satellite missions, while others use only GOCE data. This paper presents the evaluation and analysis of each approach using GOCE data in the Southeast of Brazil. Two assessments have been made. We compared the geoid heights derived from GOCE-based models with the geoidal heights from 176 GPS stations on leveling benchmarks. The findings show an improvement in GOCE-based models TIM_R3 (0.40 m) and DIR_R3 (0.39 m) for degree and order 210 in relation to EGM2008 (0.44 m) in terms of RMS. For the other models the results did not exceed 0.44 m. The second evaluation reports the comparison in terms of gravity disturbances between terrestrial gravity data and the models. The results, in terms of RMS and up to degree and order 210, indicate slightly low GOCO 02S values (10.34 mGal), TIM_R2 (10.37 mGal) and TIM_R3 (10.47 mGal) compared to EGM2008 (10.66 mGal). We also applied the residual terrain model and, as a result, the RMS errors were reduced by similar to 35% (similar to 6.0 mGal) in the entire area and by similar to 45% in the mountain region. (AU)

• Processo FAPESP: 06/04008-2 - GNSS: investigações e aplicações no posicionamento geodésico, em estudos relacionados com a atmosfera e na agricultura de precisão
• Beneficiário: Joao Francisco Galera Monico
• Modalidade de apoio: Auxílio à Pesquisa - Temático