Oceanography (2+1)

Wave measurements

The parameters of interest in the measurement of surface waves are wave height , wave period and wave direction. At locations near the shore wave height and wave period can be measured by using the principle of the stilling well described for tide gauges below, with an opening wide enough to let pass surface wave unhindered. Wave measurements on the shelf but at some distance from the shore can be obtained from a pressure gauge.

An instrument suitable for all location including the open ocean is the wave rider, a small surface buoy on a mooring which follows the wave motion. A vertical accelerometer built into the wave rider measures the buoy’s acceleration generated by the waves. The data are either stored internally for later retrieval or transmitted to shore. Wave riders provide information on wave height and wave period. If they are fitted with a set of 3 orthogonal accelerometers they also record wave direction.