Satellites should monitor plastic flows in the oceans

Plastic pollution in the oceans is a truly global problem. Because now the waste has even reached places where no one has been before. For example, at the bottom of the Mariana Trench almost 11,000 meters below the water surface. In principle, however, surprisingly little is known about the distribution of plastic that is no longer needed in the world’s seas. However, this would be important in order to be able to take countermeasures as effectively as possible. The European space agency ESA has therefore now started a project that should enable integrated monitoring in the long term. Until now, however, no corresponding technology is available. The first thing to do is to find a method that can automatically capture the plastic parts. In principle, this is possible with high-resolution optical cameras. However, this results in extremely large amounts of data, which makes evaluation difficult.

The technology has been tested in a special wave pool

The researchers are therefore now working on a system in which the water surface is scanned with radio waves. The radio waves are then reflected differently depending on whether they hit water or a foreign object. This approach has initially been tested to some extent in the laboratory. However, no offices had to be flooded for this, but use could be made of the infrastructure of the “Atlantic Basin” near the Dutch city of Delft. This is a 75 meter long water basin in which different types of waves and weather conditions can be simulated. Normally, parts of offshore wind farms or wave power plants are tested here. But now the researchers threw real plastic waste from the sea into the basin. They then scanned the surface with radio waves and actually got the desired results: the waste was recorded even under unfavorable conditions.

Ideally, the spread can be stopped early

That is why the technology is now being tested at sea. Initially, however, drones and research aircraft will be deployed here. These are intended to test which sensors and radio frequencies are most suitable. Under current plans, the first corresponding operations could begin in 12 to 18 months. However, the long-term goal is to convert satellite systems already in space and use them to monitor plastic waste. In this way, the situation would be continuously monitored. Improvements and deteriorations would be recognized in a timely manner. In addition, the distribution could be better understood. Ideally, action could then be taken before the waste reaches nearly inaccessible areas such as the Mariana Trench. As important as such monitoring is, the following applies: it is best to avoid the creation of plastic waste altogether. But that’s easier said than done.

Via: The Standard