Quality Test of Interpolation Methods on Different Topography Regions, Trabzon And Gümüşhane (Turkey), for Geoid Heights Modelling
20/09/2016 | 16:30 | Session 3: Local/regional geoid determination methods and models
Author(s): Emine Tanır Kayıkçı and Özge Karaaslan
Emine Tanır Kayıkçı and Özge Karaaslan
There are many interpolation methods applied for geoid height modeling using the measured orthometric and ellipsoidal heights at control points. The quality of the results of an interpolation method is related to the accuracy, and distribution of the measured points within the study area. In this study, a local geoid model was generated according to interpolation methods from the geoid undulations obtained by using GPS/Levelling data for a study area. Orthometric and ellipsoidal heights observed under the cadastral surveys for station pairs in the Trabzon and Gümüşhane region by the Land Registry and Cadastre Trabzon IX. Regional Directorate were used for computations. GPS/Levelling geoid undulations as differences between orthometric and ellipsoidal heights in the region of Trabzon and Gümüşhane were calculated for the point of interest by interpolating between sample points. Trabzon is approximately 600 km east-west direction 80, spread over an area of 30 km north-south direction and lies along the coastal areas eastern Black Sea Region of Turkey. Gümüşhane is approximately east-west direction 50, spread over an area of 65 km north-south direction and lies along inland eastern Black Sea Region of Turkey.
This study aims to examine the quality of three interpolation methods, namely the methods Weighted Mean Average, Polynomials, Multiquadric Interpolation, considering topographic properties of two study regions in eastern Black Sea Region of Turkey. To check the quality of estimated geoid heights within the study area derived applying different interpolation models, Descriptive statistics for comparison of the quality of interpolation models were determined using differences between the observed and estimated values of control points.