Are all waves the same? Definitely not! There is a large variety of all sorts of waves. A very large vessel for instance can have trouble from the smallest waves. In this blog the basic wave parameters and the effect they might have on your vessels out on the open sea will be explained.

Wave height

The simplest, and maybe the most used wave parameter, is the wave height. It is defined as the difference in height between a wave peak and a neighboring wave valley. The height of a wave plays a crucial role in planning and executing marine operations. High waves can be dangerous and have the ability to bring damage to constructions out on the open sea or near the coastline.

Swell and wind waves

The wave height can be divided into two different parts; swell and sea waves. Sea waves are referred as the waves which are locally originated by the wind. The waves which move from left to right in the figure below. Swell waves are also wind driven, but those waves have enough energy to travel well beyond the place of origin. It marches in broader lines (higher wave period) and with bigger gaps between each wave peak. Swell can be identified in figure 1 as well as the waves which are moving away from the observer.


Sea waves (small ripples) and swell out on the open ocean.

Wave period

The wave period is defined as the time it takes for two successive wave peaks to pass a specific point. The wave period is often referenced in seconds. The wave period normally varies between 1-20 seconds. The wave period is important to know, since this parameter can tell something about the energy which is stored within the wave. For example, the wave period is very long (15 seconds), means that the wave contains a lot of energy. If your ship is approximately the length of the wave period, the ship will simply glide over the small, but high energy, waves and won’t be affected that much by these waves. However, if your vessel is significantly longer than the wave period those low, but high energy, waves can affect the ship quite a bit. As a captain, its therefore important to know about the wave period, since it can affect the behavior of the vessel when small waves are forecasted.


Fetch is the uninterrupted distance over which the wind blows in the same direction as the length of the water body. The greater the fetch, the greater the wave height.

All these different wave parameters (and many more) influence the wave conditions out on the open sea and may determine whether your marine operation can be safely executed or not. Infoplaza provides accurate and precise forecasts regarding all those wave parameters. Our meteorologist are experts in both making weather and wave forecasts to guide you to the decision point, whether it’s safe to execute an operation or not.