Seasoned surfers know to avoid this dangerous ocean phenomenon, also called a cross sea.
As idyllic as beach vacations can be, you should never forget about water safety.
Always be wary of the waves, and nevereverturn your back on the ocean.
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Square waves have caused many shipwrecks and pose a potential threat to life for anyone in the water.
What happens if you get caught in a square wave?
Square waves are most dangerous for boats and ships that are further out.
So if you want to stay safe, stick to the shallows.
