Comprendre la marée, les super-marées et les mascarets

What is the tide? 

The tide refers to the upward and downward movement of oceans and seas. It is the result of the moon's attraction to the sea, but also of the earth's rotation, which generates a centrifugal force.



The phenomenon of super-tide or spring tide.

 The supermoon phenomenon occurs during celestial alignment: when the Earth, Moon and Sun are aligned in a specific configuration called syzygy. 


Source: mareeberthelotgcmc

During a supermoon, the influence is maximized by the alignment and proximity of the Moon.

  • Rising tides are higher than falling tides. 
  • Ebb tides are lower than normal tides. 

This amplification of the tides can lead to a significant increase in wave amplitude, which can make surfing conditions more powerful and intense.

Neap tides 

On the other hand, there are neap tides resulting from the perpendicular alignment of the Moon and Sun in relation to the Earth. This configuration limits the amplitude of tidal variations by reducing the difference between water levels at high and low tide.


Source: mareeberthelotgcmc

Neap tides tend to reduce tidal amplitude, which can lead to less powerful but more predictable and stable waves. This can make surfing conditions less exciting for surfers looking for more dynamic waves. However, waves can be more regular and predictable, which can be advantageous for beginners and less experienced surfers.

When to surf in Biarritz according to the marshes?

It's best to surf at mid-tide or low tide on the beaches in and around Biarritz. Generally speaking, a good tide coefficient for beginners is between 50 and 80.

  • The waves are best suited to beginners. At low tide, the ocean floor is flat right up to the shore break (where the waves break at high tide). The waves are then more regular and easier to surf. They are also smaller at low tide, making them less dangerous for beginners. 
  • More space for surfing. The beach is larger (see diagram above), offering more space. 
  • There's less effort involved in rowing. At low tide, the water is shallower, which makes it easier to row, or even to pull your board along on foot to catch waves offshore. This is important for beginners, as it means they don't tire as quickly. 

Caution! When the tide is high, it's easy to get swept out to sea. Every year, there are numerous incidents of swimmers being swept away and unable to return to the beach. However, if you understand the system, the baïnes can be very practical for surfers who want to get back to the line-up.

We've put together a selection of beaches where you can start surfing in the region if you come to visit us, so check it out on our blog.



The tidal phenomenon of tidal bores:

Tidal bores are atypical waves that form when the tide turns. They travel up rivers against the direction of the current, and can generate impressive waves.

Here are 3 points to summarize the mascarets:

  • Tidal bores are tidal waves that travel up rivers.
  • They form when the tide tilts and the water level rises.
  • In Bordeaux, also known as "Vagues de la Dordogne", tidal waves can reach heights of 1.5 to 2 meters on average in the best conditions.

Tidal bores are a natural phenomenon that attracts many tourists and sports enthusiasts. They are also an important economic asset for the regions where they occur, helping to develop activities such as tourism, fishing and shipping. In Gironde, the next tidal bore is scheduled for August 30 and 31, 2023. 


Source: The Saint-Pardon tidal bore, seen from a drone last September. Photo credit: Guillaume Bonnaud / SUD OUEST