Navigation General · Tides
To find the height of tide at a time between high and low water at a reference station, the navigator uses the Tide Tables together with:
- AThe Light List
- BAn interpolation (e.g., Table 3 / the rule of twelfths) for the intermediate time✓ Correct
- CThe radar
- DThe deviation card
Explanation
The Tide Tables list the times and heights of high and low water; the height at an intermediate time is interpolated using the table's height-between-tides method (or, as an estimate, the rule of twelfths). Secondary-station corrections adjust the reference values.
Authority: NOAA Tide Tables
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