Sentinel-3B: monitoring our oceans and land

12 May 2018

Earth Observation

Share this article

In March 2018 people in Eastern Europe and Russia woke up to find their snow cover had turned orange. Far from having woken up on Mars, a mix of snow with Saharan dust blown across the Mediterranean Sea had given their ski slopes its strange hue. Thanks to Sentinel Satellites, scientists were able to study precise images of this unusual phenomenon.

Capturing Saharan dust

With Sentinel-3B successfully launched on April 25^th, the repeat cycle offered by the Sentinel-3 “family” is set to improve. Sentinel-3B, as well as its twin satellite -3A, operational in orbit since 2016, has a two-pronged maritime and terrestrial mission, encompassing oceanography, land hydrology and vegetation monitoring on land.

Built by Thales Alenia Space on behalf of ESA within the scope of the European Union’s Copernicus program, Sentinel-3 satellites are dedicated to a wide range of applications. They will be useful in monitoring maritime transport, for example by detecting icebergs, and measuring the height and movement of waves. This is vital data, enabling us to improve maritime safety. Sea and ocean colour data will also be analysed to measure the sea and land surface temperature and to identify areas with algae and phytoplankton – information that will prove invaluable to the fishing industry and support the detection of algal bloom pollution.

At the same time, services based on Sentinel-3 data will greatly benefit agriculture. Having accurate and up-to-date information is an ideal way to help farmers monitor any changes in their crops and land use.

“Sentinel 3B has a very impressive data accuracy that is really without any comparison,” says Sandrine Mathieu, Product Line Manager for Meteorology and Oceanography at Thales Alenia Space.

Following El Niño

Mounted radiometers and spectrometers are crucial for following the far-reaching effects of natural events such as El Niño, hurricanes and cyclones and even earthquakes and forest fires, all of which are measured with incredible accuracy.

With worldwide trade expected to double over the next decade -90 percent of which goes by sea- improved forecasting and nowcasting is a necessity, which will be met by the completed Copernicus programme. Sentinel-3B joins a one-of-a-kind network of satellites. As Mathieu puts it:

“The readings are extremely precise. A huge amount of work has gone into calibration of the radiometric and spectral sensors. The Sentinel satellites are a reference for the industry.”