Coastal Skipper and Yachtmaster Quiz · Tidal calculations
Using this table and today's tide at the standard port, what rate should you expect from the stream?
A table for a tidal stream. At mean springs the range at the standard port is 6.0 m and the stream runs at 3.0 knots. At mean neaps the range is 3.0 m and the stream runs at 1.5 knots. Caption: today at the standard port, high water 5.6 m and low water 0.6 m.
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2.5 knots. Stream rates are tabulated for mean springs and mean neaps, and you interpolate by the range on the day. Today's range is 5.6 minus 0.6, which is 5.0 m: two thirds of the way from the neap range (3.0 m) to the spring range (6.0 m). Two thirds of the way from 1.5 to 3.0 knots is 2.5 knots.
