Plastic pollution is one of the most serious environmental problems facing the world today. Plastic waste can harm wildlife, ecosystems, and human health, as well as contribute to climate change.
However, estimating the amount and impact of plastic pollution in the ocean is not an easy task, as plastic can vary in size, shape, and composition, and can be dispersed by currents and winds.
A new study by researchers from the University of Exeter and the University of Auckland has used a novel approach to measure the amount of plastic floating on the ocean surface.
The study, which was published in the journal Nature Geoscience on August 7, found that there is less plastic littering the ocean than scientists previously thought, but what is there could persist for a long time.
How did the researchers measure plastic pollution?
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The researchers used a combination of observational data and mathematical models to estimate the amount and distribution of plastic pollution in the ocean, as per Phys.org.
They collected data from various sources, such as satellite images, aerial surveys, ship-based observations, and beach clean-ups. They also used a 3D model of ocean circulation to simulate how plastic moves and accumulates in different regions.
The researchers focused on pieces of plastic bigger than 25 millimeters (one inch), which make up over 95% of plastic floating on the ocean.
They excluded smaller pieces of plastic, such as microplastics (less than five millimeters or 0.2 inches), which are more difficult to detect and measure.
The researchers estimated that there are about three million metric tons of plastic on the ocean surface, which is much lower than previous estimates of 25 million metric tons or more.
They also found that most of the plastic is concentrated in five subtropical gyres, which are large circular currents that trap debris in their centers.
What are the implications and challenges of the study?
The study suggested that plastic pollution in the ocean is not as bad as previously thought, but it is still a serious and growing problem that needs urgent action, as per Gulf News.
As per the study, plastic pollution in the ocean is more persistent and less degradable than previously thought, as it consists mostly of large pieces that can last for decades or centuries.
There are several implications and challenges for various fields of science and society indicated in the paper. For example:
It can help improve our understanding and monitoring of plastic pollution in the ocean, as well as its effects on marine life and ecosystems.
It can help inform and evaluate policies and actions to reduce plastic consumption, production, and disposal, as well as to increase plastic recycling and recovery.
It can help raise awareness and inspire behavioral changes among consumers and producers to prevent plastic waste from entering the ocean.
It can also pose new questions and uncertainties about the fate and impact of smaller pieces of plastic that are not accounted for by the study.
The researchers hope that their study will contribute to a more accurate and comprehensive assessment of plastic pollution in the ocean, as well as to a more effective and sustainable management of this global issue.
