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Datums for 9459465, ZACHARY BAY, UNGA IS (N. SIDE) AK


Data Quality Data from this station was collected using methodology that does not meet CO-OPS highest level of accuracy (no more than 10 cm, 95% Confidence Interval (CI) referenced to a tidal datum). Recognizing that lower quality data can be used for certain applications CO-OPS is making this data available to its users with restraint. The average six-minute water level observations derived from this system have an accuracy ranging from 10.0 - 30.0 cm, 95% CI on datum. Users are cautioned to consider the accuracy of these data before using them for critical navigational or coastal engineering purposes.
NOTICE: All data values are relative to the MLLW.

Elevations on Mean Lower Low Water

Station: 9459465, ZACHARY BAY, UNGA IS (N. SIDE), AK
Status: Accepted (Jan 16 2018)
Units: Feet
Control Station: 9459450 Sand Point, AK
T.M.: 135
Epoch: 1983-2001
Datum: MLLW
DatumValueDescription
MHHW7.43Mean Higher-High Water
MHW6.71Mean High Water
MTL4.02Mean Tide Level
MSL3.97Mean Sea Level
DTL3.72Mean Diurnal Tide Level
MLW1.33Mean Low Water
MLLW0.00Mean Lower-Low Water
NAVD88
STND-30.60Station Datum
GT7.43Great Diurnal Range
MN5.37Mean Range of Tide
DHQ0.73Mean Diurnal High Water Inequality
DLQ1.33Mean Diurnal Low Water Inequality
HWI11.28Greenwich High Water Interval (in hours)
LWI5.00Greenwich 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
HAT9.80Highest Astronomical Tide
HAT Date & Time12/12/1985 22:48HAT Date and Time
LAT-3.00Lowest Astronomical Tide
LAT Date & Time06/22/1986 17:36LAT Date and Time
Tidal Datum Analysis Periods
08/01/2017 - 08/31/2017




Products available at 9459465 ZACHARY BAY, UNGA IS (N. SIDE), AK

Revised: 10/15/2013
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services