SHADE: A MATLAB toolbox and graphical user interface for the empirical de-correlation of GRACE monthly solutions

The Gravity Recovery and Climate Experiment (GRACE) mission provided monthly solutions of the Earth's gravitational field that are heavily influenced by noise. In this paper, we review the empirical de-correlation filter, designed for the post-processing removal of correlated errors in GRACE Level 2 data. We provide a detailed description of all filtering parameters along with their implementation strategies selected by previous studies. We present and discuss some aspects regarding the properties of the de-correlated GRACE data. We also design an integrated software, named SHADE (Spherical HArmonic coefficient empirical DE-correlation), for implementing the empirical de-correlation filter. SHADE is an open source software developed using MATLAB and consists of a toolbox and a graphical user interface (GUI). SHADE is designed to fully generalize the selection of filtering parameters. We test SHADE using one monthly solution of GRACE data and perform a comparison analysis using different sets of commonly used parameters.