Application of the PCA/EOF method for the analysis and modelling of temporal variations of geoid heights over Poland

Abstract

Temporal variations of geoid heights are vitally important in geodesy and Earth science. They are essentially needed for dynamic and kinematic updates of the static geoid model. These temporal variations, which substantially differ for different geographic locations, can successfully be determined using the Gravity Recovery And Climate Experiment (GRACE) mission data. So far, statistical decomposition methods, e.g. the Principal Component Analysis/Empirical Orthogonal Function (PCA/EOF) method, have not been implemented for the analysis and modelling of temporal mass variations within the Earth's system over the area of Poland. The aim of this contribution is to analyse and model temporal variations of geoid heights obtained from GRACE mission data over the area of Poland using the PCA/EOF method. Temporal variations of geoid heights were obtained from the latest release, i.e. release five, of monthly GRACE-based Global Geopotential Models. They can reach the level of 10 mm. The PCA modes and their corresponding EOF loading patterns were estimated using two different algorithms. The results obtained revealed that significant part of the signal of temporal variations of geoid heights over Poland can be obtained from the first three PCA modes and EOF loading patterns. They demonstrate the suitability of the PCA/EOF method for analysing and modelling temporal variations of geoid heights over the area investigated.

Geodesy and Cartography

“…The Principal Component Analysis/Empirical Orthogonal Function (PCA/EOF) method was applied for both, analysis and modelling temporal variations of geoid heights (Godah et al, 2018c). It was shown that the use of the first PCA mode and EOF loading pattern allows to obtain a large signal of temporal variations of geoid heights over the area of Poland (96.3%, in terms of total variance) while with the first three PCA modes and EOF loading patterns ~99.93% of total variance of temporal variations of geoid heights can be obtained.…”

“…They were analysed and modelled using two methods: SD method and the PCA/EOF method (Godah et al, 2018b). In the area investigated PCA/EOF method provides slightly better results compared to the Fourier analysis and SD methods (Godah et al, 2018c).…”

Assessment of recent global geopotential models based on the Auvergne test area data

“…From the past to the present, researchers have calculated many parameters such as local or global geoid models, gravity anomalies (free-air and Bouguer), and gravity disturbances for different regions of the earth by using GGMs. As a result of these calculations, many different methods and approaches have been put forward [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”

On the Recovery of Temporal Variations of Geoid Heights Determined With the Use of GGMS Based on SST-Hl Data From Non-Dedicated Gravity Satellite Missions

“…Recent studies, e.g. Rangelova (2007), Rangelova and Sideris (2008), Rangelova et al (2010), Krynski et al (2014) and Godah et al (2017Godah et al ( , 2018, reveled the importance of temporal variations of geoid heights for high accuracy regional geoid modelling that has been considered as one of the activities of the Joint Study Group 0.15 (JSG 0.15) of the Commission 2 -Gravity Field of the International Association of Geodesy (IAG) (see Drewes et al 2016).…”