HOW DO THE WAVES ORIGINATE?

 To find perfect and solitary waves, we must first know the bases and fundamentals of why and how waves originate and their interaction with the coast. 

The waves are the faithful expression of the seabed, the wind and the swell. The swell lines and the bottom are two lines that intersect creating this magical way of life. Each wave is unique, and we know it from experience.

Waves, they exist thanks to the sun; its heat heats the surface of the earth irregularly; towards the equatorial zones, the sun's rays make contact in an almost perpendicular way on the earth's surface, generating large masses of hot air that seek outlets towards areas of colder air. These movements of air from warm areas to cold areas are what generate the wind (this is the reason why at sunrise and sunset there is usually less wind, since the temperature of the land and the sea are equal, so no air displacement).

The wind disturbs the surface of the sea, these disturbances travel hundreds or thousands of kilometers (swell), becoming more organized and powerful with each kilometer they travel until they reach the shore, where we can finally observe it at its best: like a long wall that it unrolls orderly along hundreds of meters, or simply like a mass of water that rises and falls in unison, crushing the dreams of the most innocent of surfers.

 Factors that influence the type of wave:

The type, quality, and shape of the wave will depend fundamentally on:

– The place where the disturbance originated on the sea surface (swell) and the distance it traveled to reach the shore.

– How long the wind blew at the point where the swell originated.

– For what distance the wind blew at the point of origin of the swell.

– The type of bottom of the beach or place of surf (rocks, sand, coral) and their arrangement on the seabed (Bathymetry)

– The angle between the direction of the swell and the surf line.

– Local wind conditions (onshore, offshore, cross) and currents that can improve or damage the quality of the wave.

 

WHY ARE THERE WAVES THAT BREAK FOR HUNDREDS OF METERS AND OTHERS THAT SIMPLY CLOSE COMPLETELY WHEN MAKING CONTACT WITH THE SHORE? 

If we only look at the swell direction, In the direction of the surf line (bottom) and in the interaction between these two lines we can classify the waves from short to long.

To know the direction of the Swell you just have to look at the wave forecast and look at the angle and direction it indicates; To know the orientation of the surf you can see a map or an aerial/satellite photo in Google Earth.(1)

In the following image we see a North swell (310º), which interacts with a north-facing bay at an angle very similar to the break line of the rocky point, generating a perfect wave that travels hundreds of meters. On the contrary, the same swell interacts at an angle of almost 90º with the beach or bay that is located towards the upper part of the image, generating a very fast wave this time, probably closing completely and hardly surfable.

 

 
 long wave. Ex: Punta de Lobos (Chile), Mundaka (Spain).

It occurs when the direction of the Swell and the line of the surf (bottom) are almost parallel, that is, when they form an angle between 0° and 25°. The wave almost always breaks at the same point, advancing slowly to the side.

 In places like Chile, the best waves generally follow this pattern, they are found at the southern end of north-facing bays, where large swells from the south cause a phenomenon called Refraction (image 1), which occurs when this swell turns and surrounds this generally rocky ledge, drastically changing the direction of the swell and creating interactions between it and the bottom at angles between 0 and 25º.

 

Wave neither short nor long. Ex: El Palmar (Spain), Punta Teatinos (Chile)

These are the majority of surfable waves in the world. Here the Swell touches bottom forming an angle between 25° and 50°. In these waves the surf is less lateral than in the previous one and if the angle is high you have to surf the wave quickly so that the foam doesn't catch you.

 
Short and fast wave. Ex: Reñaca (Chile)

For angles of more than 50°, riding the side wave becomes a feat, since you have to go very fast if you don't want to get caught on the lip. If the angle is greater than 80° it becomes an impossible mission to get out of there since it will most likely close you out.

 

La angle rule It is true both on the rock bottom and on the sand bottom, the only thing to keep in mind is that the sandbanks move with the currents, so every day is a different story. (1).

 Friends. From today we will be wave seekers, always trying to find sharp angles (between 0 and 50º) between the direction of the swell and the surf line. Can you recognize which spot is in the image above? If you know, mention it in the comments. A clue, it's in Chile!

 

Now, enjoy and share the knowledge!

FLYSURF BOARDS, #SurfBetterNow.

www.flysurfboards.es

Bibliography.

(1) Atlantic Surf.

(2) Surf Science, Tony Butt, 2013.