Science

Sentinel-2A catches a wave ... from space

Reflection of solar radiation by the sea surface reveals the complex patterns of waves as they interact with the coastline and seafloor
Reflection of solar radiation by the sea surface reveals the complex patterns of waves as they interact with the coastline and seafloor
View 2 Images
Sentinel-2A’s multispectral imager provides a view of the tilting facets of the waves, expressed as measurable intensity contrasts – scientists first transformed these radiances into estimates of sea-surface slope and then ran a cross-spectral analysis to determine the wave spectrum and wave velocity
1/2
Sentinel-2A’s multispectral imager provides a view of the tilting facets of the waves, expressed as measurable intensity contrasts – scientists first transformed these radiances into estimates of sea-surface slope and then ran a cross-spectral analysis to determine the wave spectrum and wave velocity
Reflection of solar radiation by the sea surface reveals the complex patterns of waves as they interact with the coastline and seafloor
2/2
Reflection of solar radiation by the sea surface reveals the complex patterns of waves as they interact with the coastline and seafloor

Hot on the heels of its cloud-free image of Africa, the European Space Agency's Sentinel-2A has captured an image of waves hitting Dorre Island, Western Australia. The picture provides more information on how waves interact with the coastline, proving the potential benefits of satellite imaging in forecasting waves.

According to ESA, it can be difficult to measure ocean waves using buoys and ships. This poses a problem for engineers designing ships or offshore structures, because they need to know their designs will be able to handle the worst possible conditions out at sea. Ocean waves also slow ships down, threaten oil and gas extraction and erode coastlines.

As well as surface waves, which are caused by the wind blowing across the ocean surface, internal waves, currents, eddies and algal blooms all contribute to the way the ocean moves. This makes it tough to form an accurate picture of where the waves are heading, and what's making them do it.

Sentinel-2A’s multispectral imager provides a view of the tilting facets of the waves, expressed as measurable intensity contrasts – scientists first transformed these radiances into estimates of sea-surface slope and then ran a cross-spectral analysis to determine the wave spectrum and wave velocity
Sentinel-2A’s multispectral imager provides a view of the tilting facets of the waves, expressed as measurable intensity contrasts – scientists first transformed these radiances into estimates of sea-surface slope and then ran a cross-spectral analysis to determine the wave spectrum and wave velocity

In Sentinel-2A's image, the reflection of the sunlight provides a good look at the complex patterns formed by waves hitting the coast of Dorre Island. The picture shows waves that have been reflected and bent by the seabed and coastal features of the island, along with breakers rolling all the way to the shoreline.

Interesting as this is, the real benefit of the image, taken on October 1, 2015, comes by taking full advantage of the Sentinel's multispectral camera. The data captured allows ocean scientists to determine the distribution of the waves, as well working out which direction they're heading.

"Scientists at OceanDataLab processed the data to determine the distribution of ocean waves and the direction they are heading," says the ESA's Craig Donlon. "This is extremely important for anyone working at sea."

Source: European Space Agency

0 comments
There are no comments. Be the first!
Thanks for reading our articles. Please consider subscribing to New Atlas Plus.
By doing so you will be supporting independent journalism, plus you will get the benefits of a faster, ad-free experience.