Sentinel-2A is demonstrating how it can be used to help forecast ocean waves around our coasts: sunlight reflected from the water surface reveals complex waves as they encounter the coastline and seafloor off the tip of Dorre Island, Western Australia.

Measuring ocean waves from buoys and ships is difficult, so developing new ways of measuring these features from space is key to keeping safe at sea and to understanding our oceans.

Surface waves are generated by the wind. The faster and longer the wind blows and the bigger the area over which it blows, the larger the waves.

As well as providing essential safety information for mariners, wave forecasts are also important for other activities at sea.