The show is still on. Carried by important coefficients, the Atlantic Ocean likes to withdraw far from our coasts, for the greatest pleasure of the amateurs of fishing on foot. But be careful! Because a few hours after having withdrawn, the water will return at full gallop, sometimes having fun crashing on the coast for a well-known spectacle in Saint-Malo. Since Monday, February 20, the high tides have arrived. But do you know what causes them? Contrary to what one might think, the reason is not under water but very high… In space, at the level of the moon.
Every day, the rotation of the Earth on itself generates a tidal phenomenon. When an ocean is in the axis of the moon, the gravitational force causes a phenomenon of high tide, the water being attracted by the moon. Conversely, it drops when it is no longer in line with our night star. To explain the role of this centrifugal force of the Earth, some sometimes use the image of a car. When cornering, the vehicle tends to pull you outward. It is the same with the rotation of our planet.
The big coefficients come back regularly
The phenomenon of high tides is due to the approach of the moon. The latter taking a little more than 27 days to circle the Earth, the large coefficients return each month but shift little by little. To have very high tides, we can also count on the alignment of the Earth, the moon and the sun, which leads to a greater attraction.
Much appreciated by fishermen on foot, high tides are sometimes the scene of dramatic accidents. Before venturing onto the rocks or sandbanks freed from the water, it is essential to find out about the tide times and anticipate its return. Rescuers also advise to always carry a mobile phone and to look at the coast regularly to realize the distance. During high coefficients, the sea rises very quickly and generates strong currents.