Coastal Processes - Waves

In reality, one may see the wave-like water disturbance because of the energy levels carried in the body. The energy existing in the water creates the ability to transform the water shapes into ripples, for example. Waves consist of different physical attributes and stay vulnerable to occurrences of different weather patterns. 

Waves comprise different characters and focus on a few physical matters for example length, height and time. The wave height, for example, presents the vertical distance between the wave peak or top and the furrow. The length of the wave is the number of “waves” at a certain point in time. 

These waves impact on the development of the natural marine environment and the subsequent breakdown thereof. For us to understand the wave coastal processes, we need additional scientific information and understanding. Let us see the types of waves and the manner they execute the coastal processes and impact on the environment. 

What is the role of waves in coastal processes?

Waves offer a key characterisation, namely their ability to move around the globe for thousands of kilometres. One key aspect to remember relates to wave physics and the associated movement. Energy forms a critical part of the wave development and the ability to cross significant distances. The energy within the wave passes on while sediment on the seafloor keeps on circling. Also, one should remember that the wave shapes pass on and not the water in itself.

Another key concept relates to the wave base or water depth. The circle’s diameters become minor at water depth and changes to half of the wavelength size. Also, the wave’s speed tends to decrease closer to the coastline. It still travels at a high speed when the first wave started and when coming closer starts to slow down. At the shoreline, the different waves become concentrated and the heights start to increase. The waves become unsteady and collapse into wave breaks. The energy of the waves become transferred on to the coastal zone or beach area.

Understanding Waves

Why do we discuss waves in such detail? It becomes important to explain the use of energy to transport sediments using the waves. The waves allow for the transportation of sand, particles, rocks, and limestone for disposition at the beaches. 

Understanding waves form a significant part of gaining an insight into coastal erosion. The occurrence of climate change made scientists decide on investigating the concept a bit more. The more frequently the coastlines experience high-energy waves, the more likely the coastal zones may erode. It also allows for the expansion of the beach areas. It sounds great to think of a larger beach, but not so much if you live next to it.

The higher the waves, the more likely your breaks may cut into the existing beach area. How many times did you sit and while watching them, a sudden wave comes closer than you thought? We continue to experience more and more coastal floods. Also, wave build-ups towards the coastline. 

In terms of the movement of energy and waves, one also needs to look into the beach sands. Sandbanks continuously change in form and move because of wave impacts. It depends significantly on the size and height of the waves. After a wave breaks, it moves forward while maintaining the motion. As soon as the wave stops, the breaking process starts, and it continues until it reaches the beach area.

The wave speed also plays a role when the wave becomes less and the surface gets closer. 

Waves consist of different forms, shapes, and sizes. Each form impacts on the ocean processes differently.

Capillary waves

Capillary waves one first notice on the ocean surface during the start of wind. They also present short time waves. 

Gravity waves

Gravity waves experience constant wind impacts over a significant distance. Waves increase in length and the time of existence as well. Here gravity restores the surface tension and keeps the wave from extending even more.  

Free waves

Free waves we see as waves that break away from the controlled ones and move freely. These waves consist of small size and normally less-likely to impact significantly. 

Long-time waves

Long-time waves normally last over five minutes. The main reasons these well-structured waves occur are because of extensive weather conditions, earthquakes, and other climate-related impacts. These long-time waves happen because of storm flows or tsunamis, for example. Gravity plays a key role to calm down these significant and majestic waves sizes.


Tides normally happen because of the earth’s movement and the role gravity plays. It also becomes influenced by the size and length in distance of the moon as well as the sun. Different tides exist impacted by the diverse bodies for example high or low tide and spring tide. Normally during the full moon, it seems significantly more intense. In the event of a full moon, for example, one tends to see lengthier and longer-term waves.  

Standing Waves

Standing Waves we normally find in enclosed areas, for example, a harbour. Here the wave remains uniform without moving either horizontal or vertical. 

Frequently Asked Questions

What are Coastal Processes? 

Coastal processes allow for the build-up and breakdown of coastal areas. Meaning the processes ensure for constant change to happen by the use of energy. These energy resources one finds in the wind, waves or tides. Climate and weather patterns play a key role during these processes. Stormy weather increases the influences of coastal courses, for example.

What is the role of waves?

Waves form part of the coastal processes and allow for the build-up or breakdown of the natural environment. Waves cause increased or new dunes that shape our coastal areas. It also plays a role to move sediment from one place to the other.   

What do we mean by the transportation of sediment? 

Transportation of sediment happens when the waves, for example, pick up the particles and drop them in another area. It particularly happens if the waves cannot continue to carry heavy fragments. They, therefore, drop to reach the seabed.

What are wave and coastal erosion? 

Waves break down different pieces of sediments and rocks that drop down to the ocean floor or transported to the beach area. The continue occurrence of waves at the beach areas, especially during stormy weather changes the beach outline. It cuts into the beach areas.

What can we expect from climate change and waves? 

The more our weather patterns change, the more we experience storms, hurricanes, and typhoons. Subsequently, the waves experience added energy levels. The waves become more intense and higher. The outcome of such relates to a drastic change in flooding and extension of the coastal zone areas or shorelines.

Are waves good or bad? 

We want to see the positivity when looking at waves at our shorelines. The reality stays humankind faces constant challenges with the management of flooding at our beach areas. We, therefore, need more efforts to understand the change in our weather systems and the effect on the wave characterisations. 

The more energy the waves carry, they most likely result in occurrences of tsunamis or significantly larger waves. Higher waves carry large numbers of energy and impacts on the coastal development areas. Waves carry good and bad characteristics from a human point of view.  


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