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Regional Models

Macas City - Ecuador (GEOID-MACAS2021)

  Author: I.P. Orejuela     Created: 2021    Resp: I.P. Orejuela  
      Status: PUBLIC   Licence: CC BY 4.0

The GEOID-MACAS2021 model for the urban area of the Macas City in Ecuadorian Amazon was computed with a non-conventional technique, such as Cokriging (Goovaerts, 1997), through the combination of GPS data/differential leveling and a densely sampled auxiliary variable. The GPS satellite positioning was performed using the Static Differential method through dual-frequency receivers in each point; regarding the level heights they were obtained by first-order differential leveling and the GPS leveling technique. A total of 17 geoid undulation data were used for the computation, while the geoid undulation from the EGM2008 model with a spatial resolution of 1 arc-min was proposed as an auxiliary variable for the interpolation (Odera & Fukuda, 2015). The ordinary Cokriging predictor was used for the study. In order to check the fit of the resulting geoid model, a cross-validation was carried out using the “leave one out” principle, obtained an RMSE of 5.3 cm. In addition, a validation was performed with external GPS/leveling data, reaching an accuracy of 2.1 cm RMSE. This model presents auspicious results for engineering applications, for obtaining level heights quickly and accurately.

Model Citation:
I.F. Palacios Orejuela (2021). The geometric geoid of Macas City: GEOID-MACAS2021. V. 1.0. GFZ Data Services. DOI: 10.5880/isg.2021.007

I.P. Orejuela (2021). Obtención de Modelo de Ondulación Geoidal mediante Cokriging para la Ciudad de Macas – Ecuador. Presented at SIRGAS Symposium 2021, 29 November - 1 December 2021, online.

Digital object identifier:
DOI: 10.5880/isg.2021.007 (geoid in ISG format)