Tidal Streams Tutorial. Understanding tidal streams. A basic overview on how to read & understand a tidal stream atlas

1. TIDAL STREAMS
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A SIMPLE GUIDE..

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WHAT ARE TIDAL STREAMS?
▸ A movement of a body of water
▸ Flood = Rising tide
▸ Ebb = Falling tide
WHERE CAN I FIND TIDAL STREAM INFORMATION?
▸ Tidal Stream Atlas
▸ Tidal Diamonds on a Chart (see separate tutorial)
▸ Websites
▸ Apps

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WHY SHOULD I UNDERSTAND TIDAL STREAMS?
▸ Wind vs. Tide = Rougher Conditions
▸ Wind with Tide = Smoother Conditions
▸ Travelling with the tidal stream will make your journey quicker
▸ Travelling against the tidal stream will make your journey slower

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HOW DO SPRINGS & NEAP TIDES EFFECT TIDAL
STREAMS?
▸ Tidal Stream flow will be
stronger / faster during Spring
Tides when the tidal range is
larger.
▸ Tidal Stream flow will be
weaker / slower during Neap
Tides when the tidal range is
smaller.

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INTERPRETING A TIDAL STREAM ATLAS
▸ Arrows = Direction of flow
▸ Thickness of arrow = Strength of
flow i.e. the thicker it is the faster
the flow!
▸ Numbers represent the strength/
rate of the flow in knots

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INTERPRETING A TIDAL STREAM ATLAS - RATE OF FLOW
▸ The first Number shows the rate
of flow during a Neap Tide
▸ The second number shows the
rate of flow during a Spring Tide.
▸ E.G. 07, 13 = 0.7 knots (Neap
Tide) and 1.3 knots (Spring Tide)

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INTERPRETING A TIDAL STREAM ATLAS - DIRECTION OF FLOW
▸ Arrows = Direction of flow
▸ Place your Plotter inline & in the
direction of the arrow to find the
flow direction.

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DIRECTION OF FLOW OVER 12 HOURS
▸ A tidal stream atlas
will show the
changing direction
of flow during the
period between
Low Water & High
Water

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TIDAL STREAM ATLAS INFORMATION:
▸ Ensure you’re using the right Tidal Stream
information for your location
▸ Find the Tidal information for the day you’re
going afloat
▸ Insert the tide time and height next to the HW
and LW pages
▸ If further detail is required (rather than a rough
guide) need to add more detail use a Tidal
Curve to calculate the tidal height & time for
each hour (see Tidal Curve Tutorial)

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