2:30 PM - 2:45 PM
[SGD01-04] Capability of ICA Method for separating GIA and Ice Mass Signals in Antarctica
Keywords:GRACE, GIA, ICA
We primarily employed GRACE RL05 mascon data provided by NASA Jet Propulsion Laboratory (JPL) of all the GRACE available period from January 2002 to June 2017 with the spatial coverage of all Antarctica. And we used three ICA methods, namely, spatial ICA (sICA), temporal ICA (tICA), and spatio-temporal ICA (stICA), for testing the characteristics and/or the capabilities of the methods.
The results showed that the GIA like signal can be recovered successfully with sICA which separated GIA signals and AIS mass change signals into two statistical independent components. On the other hand, tICA decomposed the GIA signal into two independent components. This suggested that tICA could not solve the signals mixing problem completely. Nevertheless, tICA detected an extra anomaly snow-fall signal around 2010. This shows that tICA may have the potential to separate long-term trend signals with different time scales. The results of stICA suggested that its characteristics could be seen as a combination of the above two methods. Thus, an appropriate combination of the methods should be examined.
We also tested other datasets and revealed the different datasets and/or pre-processing of the datasets largely affected the obtained results. It is impossible to assess the validity of the results only using the GRACE data. Therefore, additional information should be necessary to validate and interpret the results.