1872 - 1929,1937 values based on 1 reading per day
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 11-JUN-91 :
Daugavgriva         080/081 RLR(1938) is 5.6m below BM Lighthouse
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 17-MAR-93 :
Possible datum shift in RLR record after the data gap around 1920.
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 11-JUL-94 :
This station is in Latvia. Daugavgriva is an historic station last data 1938

