What does the term 'duration of wind' refer to in terms of swell size?

The term 'duration of wind' specifically refers to how long the wind blows in a consistent direction over the surface of the water. This duration plays a critical role in wave formation and the generation of swell size. When wind blows steadily for a longer period, it transfers more energy to the water, allowing waves to grow in size as they gather energy and momentum.

In contrast, while the speed of the wind and the distance the waves travel influence wave characteristics, they don't directly define 'duration of wind.' Similarly, the height of the waves is a result of various factors, including wind speed and duration, but does not define the term itself. Understanding the importance of wind duration helps lifeguards and surfers predict and assess conditions effectively for safety and enjoyment in the water.