## Results
### Comparison with Fremantle  
Figures 4-9 prove that some of the alignments proposed by the PSMSL are likely incorrect. They are producing rising and accelerating trends in composing segments where the sea level is not rising. However, the proposed method did not make it possible to produce a reliable time series to be used to compute the sea level rate of rise and acceleration. If the measurements for the past were not taken properly--in the same location, with the same tide gauge, continuously--there is no opportunity to reconstruct a reliable time series. While different alignment techniques may certainly be proposed, all these works will remain subjective reanalyses of segments in a record, which are impossible to couple together to form a reliable individual time series. From Figures 4-9, it is possible to claim that it is more likely that the sea levels have been mostly stable in Aden, Mumbai, and Karachi, rather than rising at the rates and accelerations proposed by the PSMSL RLR data. Especially for Aden and Karachi, the rates of rise and the accelerations were  
Figure 9: Mumbai. (**a**) Linear fittings applied to the five segments. (**b**) MSL aligned compared to the PSMSL RLR data. (**c**) MSL aligned the same method, but only three segments, as in [2; 21], compared to the PSMSL RLR data. When measured, the sea levels were decreasing. The rising trend of the PSMSL RLR data was the result of the shifts of one segment versus the other, always upwards versus the values suggested by the alignment of the breakpoints. certainly overrated in the PSMSL RLR data. However, there was no opportunity to know with accuracy the precise values of sea level rate of rise and acceleration. Long-term segmented tide gauges should be compared with long-term non-segmented tide gauges in the same basin to discover differences. We considered the tide gauge of Fremantle, in Australia, the best tide gauge of the Indian Ocean [29], Figure 10. The PSMSL RLR data downloaded from www.psmsl.org/data/obtaining/stations/111.php on 6 June 2018, with date range January 1897 to December 2016, suggest a relative rate of rise of +1.67 mm/yr and acceleration of +0.006 mm/yr\({}^{2}\). The completeness of the tide gauge is 92%. By filling the gaps interpolating the data from the same month in neighboring years, the relative rate of rise becomes +1.70 mm/yr and the acceleration +0.005 mm/yr\({}^{2}\). The rate of rise of the sea level is less than the subsidence rate of the nearby GPS dome of PERT (in Landsdale). According to SONEL (www.sonel.org), the subsidence rate of this inland dome is \(-2.09\pm 0.38\) mm/yr. Even larger subsidence was found by SONEL for the similarly close inland GPS dome of HIL1 (in Hillarys). The subsidence rate here is here \(-2.78\pm 0.31\) mm/yr. Figure 10: Cont. According to JPL (sideshow.jpl.nasa.gov/post/series.html), the subsidence rate for PERT (in Landsdale) is \(-2.883\pm 0.612\) mm/yr. While the Freemantle tide gauge may be subjected to reduced subsidence compared to the GPS domes of PERT (in Landsdale) or HIL1 (in Hil Hil arrays), certainly all the Perth basin is subjected to subsidence [30; 31]. Nevada Geodetic Lab (geodesy.unr.edu) has many more GPS antennas in the area. PERT (in Landsdale) has a subsidence rate of \(-1.933\pm 0.603\) mm/yr; HIL1 (in Hil arrays) has a subsidence rate of \(-1.933\pm 0.603\) mm/yr. Figure 10: Freemantle. (**a**) and (**b**) linear and parabolic fittings of the PSMSL RLR data, as it is or with gaps filled. (**c**) and (**d**) subsidence rates of nearby GPS domes. Images reproduced and modified from SONEL, www.sonel.org. (**e**) Periodogram of the PSMSL RLR data with gaps filled about the parabolic trend. rate of \(-2.821\pm 0.603\) mm/yr. Moving closer to the tide gauge location, WLT1 (in Willetton) has a subsidence rate of \(-3.821\pm 1.231\) mm/yr, CUTA and SPA8, both slightly south of East Victoria Park, about the location of Curtin University, have a subsidence rate of \(-1.108\pm 0.944\) mm/yr, and\(-3.795\pm 1.529\) mm/yr. respectively.