Most waves in the ocean are generated by wind blowing across the sea surface. As the wind blows over the ocean it pushes parallel to the ocean surface as well as down onto the surface. This causes water to pile up into small waves. As wind continues to blow on these ripples, the height, length, and speed of the wave increases. There is no more energy transfer once the speed of the wave equals the speed of the wind and the wave has reached its max size. Once a wave forms, it can travel long distances, unaided by wind, as such wavy conditions may be observed in a calm and windless area. In this way, the size of waves in an area is not always associated with current wind conditions.
The data in this nugget highlight the relationships between wind speed, wave height, and wave period and how these properties vary throughout the year at the OOI Coastal Endurance Array Oregon Offshore Surface Mooring. Though there is a general relationship between wind and waves (e.g. stronger winds are often associated with larger waves), the spread in the data also showcases times where the buoy detected waves that were not generated locally (e.g. times where local winds are weaker but waves are still relatively large). Looking at the annual cycle, wind and waves are both larger during the stormy winter, and smaller during the calm summer.
Near the location of this mooring off the coast of Newport OR, an open water wave energy testing facility is in development as a partnership with Oregon State University and the Department of Energy – PacWave. It will be interesting to see the waves observed by this mooring become energy to charge your cell phone, power a microwave, or maybe even run an electric car.