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We have extracted long coastal tide gauge records from the archives maintained at the Permanent Service for Mean Sea Level(PSMSL) (e.g., Holgate et al. 2013) Revised Local Reference (RLR) monthly average time series. The tide gauge recordsare affected by a variety of of physical processes at different time space resolutions (Douglas, 1991 ). Most significant tidalconstituents have periods of a few hours to nearly a day and longer periods generally have smaller amplitudes. While our use ofmonthly time series filters out shorter periods signals, the impacts of interannaul to decadals physical process are needed to befiltered out. This include land-ocean water mass exchange linked to El Nino Southern and Pacific Decadal Oscillation cycle onthe short terms sea level impacts and also North Atlantic Oscillation (NAO), i.e., a fluctuating air pressure over the differentregions of North Atlantic Ocean that invariably alters the water mass distributions Han, 2002. For instance, the intensity of LaNina between 2010 to 2011 was behind the drop of global mean sea level at a level of -7mm/yr (See Fasullo, et al. 2013). Thusthe sea level trends from tide guage records can be sensitive to the window of observations.The requirement for very long time series is, therefore, a requisite to minimize the masking of the background trend due tothe contamination of the decedal signal superimposed in the tide gauge records. The PSMSL database contain in excess ofthousands of stations distributed along the coastlines and Islands. However, they TG do contain different sampling and datalength. Thus, the selection of the TG records follow certain criteria. Douglas (1991) address the need for longer than 50 yearsand a maximum of 20% data gaps in tide gauge records. Furthermore, Douglas excluded tide gauge records sites located atconvergent tectonic plate boundaries (region of active deformation). However, the latter substantially remove usable TG recordsfor Global mean sea level studies and now GPS accurately estimate the vertical land motion rate near tectonically active areas.Ray and Douglas (2011) selected 89 gauges following mainly focusing the longest records of Tgm, while excluding gaugeswith non-GIA source of vertical land motion. Hamilgton et al. (2016) cautioned that a less stringent selection criteria maylead to VLM related errors. We employed a manual inspections of each tide gauge records and removed large data variations(anomalies). The selected station that includes Douglas (1991) 27 gold standard and the Ray and Douglas (2011) 89 selectedgauges with additional tide gauge records around the shore of Japanese seas are shown in Table 1.The ocean response to the change in atmospheric pressure, i.e., the inverse barometric corrections, are taken into account,notwithstanding a priori studies have showed that for for regional or global sea level estimate, they found that the invertedbarometric effects have minor influence on the estimate of longer sea level changes Church and White, 2011;Thompsonand Merrifield, 2014. Recent study further evidenced that, the inverted barometric effects, however small, is still significant(Dangendorf et al., 2013; Piecuch et al., 2015; Frederikse et al, 2017). For example, Ponte 2006 showed a trend change in tidegauge records up to 15% when removing the inverted barometric effects. In our global mean sea level estimate we consider the

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