22.05.2018 – Wind and wave

Today we had a choppy trip with a small school of Common dolphins ( Delphinus delphis) enjoying the waves (fluctus). We had quite a ride between the waves and it was not easy for our guests to observe the animals.

But how does a wave actually come about? Tides, wind, seabed, currents are playing an important rule in the formation of waves. However the wind is the main factor in this game. If a low pressure area is building up out on the sea this power has an impact on the ocean. The friction sets individual water particles in motion, which in turn set other water particles in motion, creating a wave. In no time a vast quantity of water is in movement. The wind propels the wave forward, the force of gravity pulls the wave into the wave trough and next wave mountain arises. In the beginning of this powerful dynamic dominates a huge wave chaos.

Waves of different sizes and speed are traveling in different directions. This situation is called “wind sea”. After a while the chaos gets organized and now the wind power concentrates on less waves and the swell is starting to building up. The developed wave transports the power of the wind forward.

The tides as well have a special impact on waves. During low tide waves break farther outside in the ocean than at high tide. Why is this like so? Since the water level is much higher during the high tide the wave can run longer.

On the base of currents our world oceans are always in motion. Through this movement waves can be created. Waves use the energy of currents to travel towards shore. Changes in coastal landscape or ocean bed has an effect on wave behavior. Factors such as earthquakes or submarine volcanic eruptions, which also contribute to the formation of waves, are not mentioned here.

Clearly such an interesting topic can only be sketched superficially. It is amazing which enormous complexity in nature exists. We will see if this will provide enough matter for 1-2-3 more blogs. :)

 As with anything in nature, there is an enormous complexity here as well. Let’s see if there is more stuff for 1-2-3 more blogs. 🙂

by Fatima Kutzschbach

Sightings of the day

Ribeira Brava

10:00 Common dolphins