Analysing Five Years of GRACE Equivalent Water Height Variations Using the Principal Component Analysis

  • I. M. Anjasmara
  • M. Kuhn
Conference paper
Part of the International Association of Geodesy Symposia book series (IAG SYMPOSIA, volume 135)


In this study we use 59 monthly solutions (April 2002–May 2007) of the Earth’s gravity field obtained from the Gravity Recovery and Climate Experiment (GRACE) satellite mission, expressed in equivalent water height (EWH). The GRACE-derived EWH values are analysed first in terms of the secular trend and RMS-variability before applying the statistically-based Principal Component Analysis (PCA), in order to obtain the most dominant spatial and temporal variations. On a global scale, we show that only 5 modes can express more than 80% of the total variability, including all major hydrological, cryospheric and post-glacial rebound signals. As expected, globally, the most dominant temporal variation is an annual signal followed by a secular trend. Apart from these well-known signals, we show that the PCA is able to reveal other periodic and a-periodic signals.


GRACE PCA Spatial and temporal variation 



This study was funded by Australia Partnership Scholarship (APS-AusAid). We thank The Institute of Geoscience Research (TIGeR) for funds to present this work at the IAG Symposium GGEO2008. We also thank Dr Oliver Baur from the Geodetic Institute of the University of Stuttgart, who kindly provided the GRACE mass estimates. Finally, we would like to thank two anonymous reviewers who helped to considerably improve the original manuscript. This is TIGeR publication 169.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  1. 1.The Institute of Geoscience Research, Western Australian Centre for Geodesy, Curtin University of TechnologyPerthAustralia

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