Porvoo is a new Finnish station with data beginning in August 2014.
Documentation added 2019-11-27
From 2018 onwards the averages of the Finnish sea level data will be based on 1 min observations. Values are calculated in Finnish normal time (EET). The data are relative to the reference surface of the Finnish sea level observations and thus the datum is the tide gauge zero.
Finnish Meteorological Institute Marine Research, Waves and Sea Level Erik Palenin aukio 1 P.O. Box 503 FI - 00101 Helsinki