Satellites can track microplastics from space

Sometimes the simplest can be the most efficient. A team from the Michigan University has used data originally collected to monitor hurricanes to try to track microplastics, which could help control a problem threatening to engulf the world’s oceans.

The annual world production of plastic has increased every year since the 1950s, reaching 359 million metric tons in 2018. Much of it ends up in open and uncontrolled landfills, where it can reach the drainage areas of rivers and ultimately the world’s oceans.

A problem to solve

These tiny plastic particles are what are produced after the sun and friction (such as ocean waves) break up larger plastic objects. These microplastics travel hundreds or thousands of kilometers because of ocean currents, which makes it difficult both to track them from the source of origin and to eliminate them. To this day, they represent a serious problem in our waters, causing havoc on ecosystems and the organisms that inhabit there. Now, thanks to this initiative, the tracking of microplastics could be as simple as it is useful.

The data used by the team was collected by the Cyclone Global Navigation Satellite System (CYGNSS) of NASA, a constellation of 8 microsatellites Launched in 2016, it typically monitors ocean and weather patterns in order to track hurricanes. Specifically, data regarding the roughness of the ocean, or how rough the ocean is, because the amount of trash found in the ocean is one of the contributing factors to this swell (also wind speed, of course). .

“We had been taking these radar measurements of surface roughness and used them to measure wind speed, and we knew that the presence of things in the water alters its responsiveness to the environment. So I had the idea to do all the other way around, using changes in responsiveness to predict the presence of things in the water “, clarifies the space and climate scientist Chris’s reputation, co-author of job that publishes the magazine IEEE Transactions on Geosciences and Remote Sensing.

The researchers looked for places where the ocean was calmer than expected, which could indicate the presence of microplastics. Then, they compared those areas with observations and model predictions of where microplastics congregate in the ocean. They found that microplastics tended to be present in calmer waters, showing that CYGNSS data can be used as a tool to track ocean microplastics From space.

Microplastics in calm waters

Specifically, global concentrations of microplastics tended to peak in the North Atlantic and Pacific during the summer months of the northern hemisphere. June and July for example, are the most outstanding months for the Great Pacific Garbage Patch. For the southern hemisphere, concentrations peak during the summer months of January and February.

The fact that there are lower concentrations of microplastics during winter in both hemispheres is probably due to a combination of stronger currents than break the microplastic feathers and one greater vertical mixing (the exchange between the surface and the deeper water) that carries part of the microplastic under the surface.

Scientists have already started discussions with the nonprofit organization Cleaning the ocean to validate your findings and power track through data of a potentially catastrophic problem.

“Yet we are in the early stages of the investigation process, but I hope this can be part of a fundamental change in the way we track and manage microplastic contamination, “says Ruf.

And it is that, with around 8 million tons of plastic believed to end up in the oceans every year, cleaning it up is already a huge task. Knowing where this plastic is and how it moves could help us get the job done faster and more efficiently.