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

Conference paper
Part of the International Association of Geodesy Symposia book series (IAG SYMPOSIA, volume 135)

Abstract

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.

Keywords

GRACE PCA Spatial and temporal variation 

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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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