Geoid Height Changes over Türkiye: Insights from GRACE and GRACEFO Spherical Harmonics


Güneş Ö., Aydın C.

EGU General Assembly 2025, Vienna, Avusturya, 27 Nisan - 02 Mayıs 2025, ss.1, (Özet Bildiri)

  • Yayın Türü: Bildiri / Özet Bildiri
  • Doi Numarası: 10.5194/egusphere-egu25-9662
  • Basıldığı Şehir: Vienna
  • Basıldığı Ülke: Avusturya
  • Sayfa Sayıları: ss.1
  • Yıldız Teknik Üniversitesi Adresli: Evet

Özet

The Gravity Recovery and Climate Experiment (GRACE) and its Follow-On mission (GRACE-FO) have

greatly improved our ability to monitor changes in Earth's mass distribution, providing

unprecedented insights into variations in total water storage (TWS). These variations can be

expressed as equivalent water thickness, and they can also be derived from other geopotential

variations, such as changes in geoid height, gravity anomalies, or vertical displacements.

Understanding these variations is essential for comprehending regional hydrology and solid Earth

dynamics.

In this study, we use DDK2-filtered solutions from GRACE and GRACE-FO spherical harmonics to

compute geoid height variations over the Türkiye region, based on roughly one hundred grid

points. The trend in the geoid height changes for this region is approximately at the millimeter

level. We also derive TWS time series from these DDK2-filtered spherical harmonics to compare

the changes in geoid height with the corresponding equivalent water thickness values, aiming to

explore the functional relationship and correlation coefficients between these two geopotential

variations. In addition to time-domain analysis, we apply spectral analysis to examine the power

spectrum of geoid height and TWS variations in the frequency-domain. This approach helps us

understand the spatial and temporal diversity of geoid height changes across Türkiye and provides

insights into their underlying patterns and trends. The preliminary results of this study offer an

overview of geoid height changes in Türkiye and highlight the potential of GRACE and GRACE-FO

data for monitoring mass redistribution on a regional scale.