What a week of waves! Last week, the East and West coast in the US saw great waves thanks to hurricanes. Our Facebook and Instagram newsfeed were full of pictures and videos that made us salivate! It’s rare that both coasts in the US get swell at the same time, so what happened?
Hurricanes. That’s what. Surfers love hurricanes. (As long as they can benefit from the waves, and not get their houses flooded.)
Southern California lit up, especially Malibu and Newport Beach, with swell generated by Hurricane Marie. And on the East coast, surfers scored too; Hurricane Cristobal generated major waves.
We hear California is gearing up for even more waves. Here in Costa Rica, we are stoked to see the swell building into the weekend. When we get waves like this, everyone is out surfing (if they can handle the size.)
With all these waves, we thought we would share a simplified version of how waves are formed. (Many thanks to this site and Surfline, where we got a refresher.)
How are waves formed?
Waves are made when wind transfers its energy from the air to the water. Three factors influence how big the waves get.
- Speed of wind: The faster the wind is traveling, the bigger a wave will be.
- Distance of wind: The farther the wind travels against the wave, the bigger it will be.
- Time of wind: The longer the length of time the wind is hitting the wave, the bigger it will be.
As waves grow larger, the distance between waves will grows too.
The biggest waves are created by storms out at sea [like Hurricane Marie and Cristobal last week]. They start out as huge, choppy waves and gradually become strong, smooth peaks (swell). The swell drags against the ocean floor as it gets nearer to the beach. That dragging causes friction, which causes the wave to grow taller, slow down and eventually break.
The shape of the ocean floor and the direction of the wind are the two main factors that cause a wave to break (crash). The best surfing waves are usually caused by sand bars, rocky points breaks or reefs. These underwater features cause the ocean floor to rise steeply, and they create the hollow tubes that surfers love. For an extreme example, look at this image from Surfline of Teahupo’o. Thousands of miles of Ocean and energy meet a really abrupt coral reef shelf… and create an amazing tube (and a devastating wipeout!)
Waves break more gently and farther out if the slope of the ocean floor is gradual. This is why certain beaches and surf spots are better than others.
Got it? That is the basics of how waves are formed. Then throw in swell direction, wind conditions, and tide, and you have the basics for surf forecasting for your surf break.
Now #getoutthere and go surf!