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Secrets of the St. Lawrence

The wind and the waves - Wave wars

Petite rivière Saint-François

- "I don't know. With this Southwesterly wind, who'd be bold enough to head out into the rising tide. It's absolute hell in the Chenal Nord!"

Wind opposing current

There are 3 types of currents in the St Lawrence and the Gulf: ocean currents, tidal currents and river currents.

Of the ocean currents, the Gaspé Current has the largest effect on waves.

But the influence of the tidal and river currents is much stronger. And when the wind enters the picture, the waves can change the sea's behaviour, sometimes dangerously.

If the current and the wind are moving in different directions, waves will build and shorten. Very quickly, the water may become a dangerous place to be.

The Northwest gyre rotates counter clockwise along the Québec shoreline near the entrance of the St. Lawrence River. The Gaspé Current flows clockwise around the Gaspé Peninsula.

Chop

When 2 currents meet or cross, even when the water is calm, they will cause the surface of the water to literally boil. This turbulence is called rip. It looks as though the water is breaking over rocks or the Loch Ness Monster is about to surface. An impressive sight, but not a dangerous one.

But as soon as the wind begins to blow against the current, the situation will quickly deteriorate. The waves will be confused, steep and breaking. The resulting chop creates absolute chaos!

Wind flows opposite to current direction creating a choppy sea surface.  The wave crests break opposite to current direction.

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