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Datums for 8441551, ROCKPORT HARBOR MA


NOTICE: All data values are relative to the MLLW.

Elevations on Mean Lower Low Water

Station: 8441551, ROCKPORT HARBOR, MA
Status: Accepted (Apr 17 2003)
Units: Feet
Control Station: 8443970 Boston, MA
T.M.: 75
Epoch: 1983-2001
Datum: MLLW
DatumValueDescription
MHHW9.46Mean Higher-High Water
MHW9.03Mean High Water
MTL4.68Mean Tide Level
MSL4.71Mean Sea Level
DTL4.73Mean Diurnal Tide Level
MLW0.32Mean Low Water
MLLW0.00Mean Lower-Low Water
NAVD88
STND-3.31Station Datum
GT9.46Great Diurnal Range
MN8.70Mean Range of Tide
DHQ0.43Mean Diurnal High Water Inequality
DLQ0.32Mean Diurnal Low Water Inequality
HWI3.68Greenwich High Water Interval (in hours)
LWI9.85Greenwich Low Water Interval (in hours)
Max TideHighest Observed Tide
Max Tide Date & Time Highest Observed Tide Date & Time
Min TideLowest Observed Tide
Min Tide Date & Time Lowest Observed Tide Date & Time
HATHighest Astronomical Tide
HAT Date & Time HAT Date and Time
LATLowest Astronomical Tide
LAT Date & Time LAT Date and Time
Tidal Datum Analysis Periods
08/01/1992 - 09/30/1992
To refer water level heights to NAVD88 (North American Vertical Datum of 1988), apply the values located at National Geodetic Survey.




Products available at 8441551 ROCKPORT HARBOR, MA

Revised: 08/08/2018
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services