Geodetic Reconciliation of Tide Gauge Network in Estonia

摘要

A network of automatic tide gauges (TG) is managed by the Estonian Environmental Agency. During the recent reconstruction of Estonian high-precision levelling network the local TG ties were remeasured. Estonia adopted EVRS (European Vertical Reference System) based height system in 2018.This datum change caused the previous heights (belonging to the obsolete 1977 Baltic Height System,BHS77) to increase from 14 cm to 25 cm in a north-westerly direction. Accordingly, the tide gauge records had to be corrected. This study also analyses corrected time series of 14 TG-s along the Estonianshoreline of a four years (2014–17) period. Statistical analysis reveals improvements in the consistency ofthe TG time-series. The standard deviation has decreased from 4.4 cm (BHS77) to 2.7 cm (EH2000), theimprovements due to new adjustment in EVRS system and taking into account effects from glacial isostatic adjustment. Records of some Finnish tide gauges (located at the northern shores of Gulf of Finland)are used for verifying the study results. New, corrected data can be used for various regional and interdisciplinary studies, e.g., confirming the land uplift values along shorelines.