# GPS Time Series Analysis from Aboa the Finnish Antarctic Research Station
## 4 Discussion
### How Do Our Results Relate to Other Published Data?  
The horizontal motion describes mainly the dynamics of the tectonic plates. There are no published values on the horizontal rates for Aboa. On the other hand, [PERSON] et al. [84] reported on a campaign-based GPS horizontal rates at Wasa, a Swedish benchmark located 200 m from Aboa, used in several SCAR measuring campaigns. Using the DD approach and a 7.9 year time span, the authors estimated 10.4 \(\pm\) 1 mm/y in the North direction and 0.5 \(\pm\) 1 mm/y in the East direction that is within 1 mm/y from our results.  
There are several global plate models including Antarctica based on either geological or geodetic data. For a comparison, we generated the plate motion velocities for Aboa as summarised in Table 7.  
Our GPS-derived horizontal rates at Aboa agree on 1 mm/y level for the north component, but varies up to 4 mm/y in the east component. The closest agreement is with the GEODVEL model. Also, the agreement with the ITRF2014 model is very good on the level of 0.3 mm/y. These models are based on geodetic data. The geological models (NNR-MORVEL56, MORVEL 2010) agree GEODVEL and our results very well in the North component but they differ 3 mm/year in the East component. This difference is partially explained in [PERSON] et al. [85], who found a large global X-rotation rate between ITRF2008 and the NNR-MORVEL56 model equivalent to a systematic bias of 2.5 mm/y at the Earth surface.  
The vertical rates from our two solutions are lower than those reported in several studies that have included Aboa in their results. Also, the uncertainty of our result is the lowest when comparing to other published values with reported uncertainties. [PERSON] et al. [5] reported 1.13 mm/y elastically adjusted GPS vertical rate for Aboa. Elastic response of the crust is caused by contemporaneous ice mass change and is interlaced in the vertical rate with a more long term trend. Their GPS-derived rate was 1.4 \(\pm\) 0.84 mm/y, while the modelled elastic rate was 0.27 mm/y. In addition, they reported 0.09 mm/y ICESat elastic rate for Aboa. These findings are based on 1959 days of observations between 2003-031 and 2010-011. [42] assessed estimated GIA uplift rates with a set of elastic-corrected GPS vertical velocities at 67 Antarctic sites from 2009 to 2014 inclusive. However, Aboa data was limited to 2013-01-08. They reported an observation rate of 1.54 \(\pm\) 0.84 mm/y. In addition, the authors reported predicted vertical rates at Aboa from several GIA models. Table 8 summarises these values. [PERSON] et al. [43] used similar GPS processing results as [42] but the start of the time series of beginning of 2010. After applying a spatio-temporal filtering, they found a vertical rate of 2.05 \(\pm\) 0.50 for Aboa. [PERSON] et al. [84] did not include Aboa but reported 3.2 mm/y campaign-based GPS vertical rate at Wasa. Using ICESat observation, they report \(-\)1.2 mm/y elastic correction for Wasa. They also report the vertical rates predicted by two GIA models: W12a (1.3 mm/y) and IJ05R2 (0.7 mm/y). Their findings were based on 7.9 year time interval. An in-depth geophysical analysis of all the vertical rates (both from GPS analysis and GIA modelling) is beyond of the scope of this study. Such comparison needs extensive analysis and comprehension of the different assumptions behind each of the models above.