11/19/2023 0 Comments Death trash costThis included the Multi-Level-Trawl expedition, where they analyzed the depth at which buoyant plastic debris may be vertically distributed the Mega Expedition using vessels to cross the patch with many trawls at once and the Aerial Expedition which involved the use of a plane flying at low altitude to observe the debris from above. Over the course of three years, researchers at The Ocean Cleanup went on several data collection missions. This method showed a bias towards smaller objects and did not provide much insight into the larger pieces, and, thus, the entire scope of the GPGP. Scientists have been studying this area since the 1970’s – usually by means of dragging a small sampling net through the debris. “To accurately quantify a problem of the size, we had to do research at a scale that had never been done before” – Boyan Slat Interaction with these discarded nets, also known as ghost nets, often results in the death of the marine life involved. Since 84% of this plastic was found to have at least one Persistent Bio-accumulative Toxic Persistent Bio-accumulative Toxic (PBT) chemical, animals consuming this debris are therefore ingesting the chemicals attached to the plastic.įishing nets account for 46% of the mass in the GPGP and they can be dangerous for animals who swim or collide into them and cannot extract themselves from the net. Laysan albatross chicks from Kure Atoll and Oahu Island have around 45% of their wet mass composed of plastics from surface waters of the GPGP. For example, sea turtles by-caught in fisheries operating within and around the patch can have up to 74% (by dry weight) of their diets composed of ocean plastics. Animals migrating through or inhabiting this area are then likely consuming plastic in the patch. These results prove that plastic pollution at sea, while densely distributed within the patch, is scattered and does not form a solid mass, thus demystifying the trash island concept.ġ80X more plastic than food at the surface of the Great Pacific Garbage Patchįloating at the surface of the Great Pacific Garbage Patch (GPGP) is 180x more plastic than marine life. The center concentration levels contain the highest density, reaching 100s of kg/km² while decreasing down to 10 kg/km² in the outermost region. The mass concentration model, pictured below, shows how the concentration levels gradually decrease by orders of magnitude towards the outside boundaries of the GPGP. Using data from multiple reconnaissance missions, a mass concentration model was produced to visualize the plastic distribution in the patch. While 1.8 trillion is a mid-range value for the total count, their calculations estimated that it may be range from 1.1 to up to 3.6 trillion pieces. Using a similar approach as they did when figuring the mass, the team chose to employ conservative estimations of the plastic count. If the less-dense outer region was also considered in the total estimate, the total mass would then be closer to 100,000 tonnes.Ī total of 1.8 trillion plastic pieces were estimated to be floating in the patch – a plastic count that is equivalent to 250 pieces of debris for every human in the world. When quantifying the mass of the GPGP, the team chose to account only for the denser center area. The center of the GPGP has the highest density and the further boundaries are the least dense. However, the team observed seasonal shift from west to east and substantial variations in latitude (North to South) depending on the year.Ĥ to 16 times more plastic in the Great Pacific Garbage Patch than Previously Estimated On average the patch orbits around 32°N and 145°W. Only floating objects that are predominantly influenced by currents and less by winds were likely to remain within the patch.īy simulating concentration levels in the North Pacific, the researchers were able to follow the location of the patch, demonstrating significant seasonal and interannual variations. LOCATIONĭue to seasonal and interannual variabilities of winds and currents, the GPGP’s location and shape are constantly changing. Sampling at different locations within the same time period allowed a more accurate estimate of the size of the patch and the plastic drifting in it. This consisted of a fleet of 30 boats, 652 surface nets and two flights over the patch to gather aerial imagery of the debris. To formulate this number, the team of scientists behind this research conducted the most elaborate sampling method ever coordinated. The Great Pacific Garbage Patch covers an estimated surface of 1.6 million square kilometers
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