The Dhaka Times Desk Everyone is concerned about plastic pollution in the ocean. Because of this, there are concerns about marine animals such as fish resources. So this time, scientists said, the ocean plastic will be detected from space!
Scientists are working on ways to detect plastic waste in the ocean from space. Debris or wreckage fragments in particular are much smaller than the minimum object size, but are very challenging to detect with satellites.
But the method works by looking for patterns of light reflected from the plastic in the water. The results of this test at the UK's Plymouth Marine Laboratory are very promising.
"You might not be able to see an individual plastic bottle floating in the ocean, but we can detect the aggregation of these materials," Dr. Lorraine Bierman.
In 2015 and 2017, two instruments called Multi-Spectral Instruments, or SSIs, were placed into orbit on the EU's Sentinel-Two satellite. It is operated by the European Space Agency, and is staffed by Earth observation scientists.
The mission's primary goal was to create an incremental map of the Earth's surface. However, this process can also capture coastal water views.
This creates an opportunity to detect plastic waste in the ocean. Because at least 8 million tons of plastic enter the seas every year through rivers or other sources. It will map part of the UK every two days via two Sentinel satellites.
Dr. According to Bierman, the resolution of the satellite camera is 10 meters, the difficulty is that this camera will only capture images of objects that are capable of producing a certain number of pixels. But some things worked in his favor.
One is that floating waste or debris that washes into the ocean is mostly plants, but it can also contain trash like plastic. Another thing about the benefits of Dr. That's the special quality of the Sentinel satellite's detector, Bierman says.
These devices have the ability to sense different wavelengths of light. That's why the Plymouth scientists can also analyze the pixels of the images captured by the camera.
Sea water strongly absorbs near-infrared radiation. Plants and other things floating in the water reflect this near-infrared light. However, if plastic is mixed with plants, some changes will also be seen.
The difference in the infrared reflection of these plants and plastics is seen as one of the ways to identify them. Beerman.
Dr. Bierman said that by collecting images of floating objects and analyzing their pixels, it is possible to tell whether there is plant material or plastic material in it. A list of objects is also created by analyzing the spectra of satellite images.
Similar trials in British Columbia and the east coast of Scotland have also shown promise. Dr. According to Bierman, this method needs further refinement. However, he felt that the results of this initial test warranted further testing.
Later the algorithm will be used to analyze the images. Searching for reasons is time-consuming and impractical. Because automation is the only way.
According to a BBC report, Dr. Bierman has monitored all the important places where plastic waste is discharged in large quantities. He is also linking the data to a database to assess the impact of pollution.
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