Fig. 2
![Fig. 2](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40623-016-0499-9/MediaObjects/40623_2016_499_Fig2_HTML.gif)
Degree amplitude of the time-variable signal described by the gravity field models considered in the study, here shown for the month of March 2015
Degree amplitude of the time-variable signal described by the gravity field models considered in the study, here shown for the month of March 2015