Navigation General · Tides
A 'subordinate' (secondary) tide station's predictions are obtained by:
- AApplying time and height differences to a listed reference station's predictions✓ Correct
- BReading them directly with no correction
- CUsing the Nautical Almanac
- DMeasuring the depth with a lead line
Explanation
Predictions for subordinate stations are derived by applying the listed time differences and height differences (or ratios) to the predicted highs and lows of the assigned reference station, since maintaining full predictions for every minor port is impractical.
Authority: NOAA Tide Tables
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