Great Pacific garbage patch

The Great Pacific garbage patch (also Pacific trash vortex) is a garbage patch, a gyre of marine debris particles, in the central North Pacific Ocean. It is located roughly from 135°W to 155°W and 35°N to 42°N. The collection of plastic and floating trash originates from the Pacific Rim, including countries in Asia, North America, and South America. The gyre is divided into two areas, the "Eastern Garbage Patch" between Hawaii and California, and the "Western Garbage Patch" extending eastward from Japan to the Hawaiian Islands.
Despite the common public perception of the patch existing as giant islands of floating garbage, its low density (4 particles per cubic meter) prevents detection by satellite imagery, or even by casual boaters or divers in the area. This is because the patch is a widely dispersed area consisting primarily of suspended "fingernail-sized or smaller bits of plastic", often microscopic, particles in the upper water column known as microplastics. Researchers from The Ocean Cleanup project claimed that the patch covers 1.6 million square kilometers. Some of the plastic in the patch is over 50 years old, and includes items (and fragments of items) such as "plastic lighters, toothbrushes, water bottles, pens, baby bottles, cell phones, plastic bags, and nurdles." The small fibers of wood pulp found throughout the patch are "believed to originate from the thousands of tons of toilet paper flushed into the oceans daily."
Research indicates that the patch is rapidly accumulating. The patch is believed to have increased "10-fold each decade" since 1945. A similar patch of floating plastic debris is found in the Atlantic Ocean, called the North Atlantic garbage patch. This growing patch contributes to other environment damage to marine ecosystems and species.
History.
The patch was described in a 1988 paper published by the National Oceanic and Atmospheric Administration (NOAA). The description was based on research by several Alaska-based researchers in 1988 who measured neustonic plastic in the North Pacific Ocean.
Researchers found relatively high concentrations of marine debris accumulating in regions governed by ocean currents. Extrapolating from findings in the Sea of Japan, the researchers hypothesized that similar conditions would occur in other parts of the Pacific where prevailing currents were favorable to the creation of relatively stable waters. They specifically indicated the North Pacific Gyre.
Charles J. Moore, returning home through the North Pacific Gyre after competing in the Transpacific Yacht Race in 1997, claimed to have come upon an enormous stretch of floating debris. Moore alerted the oceanographer Curtis Ebbesmeyer, who subsequently dubbed the region the "Eastern Garbage Patch" (EGP). The area is frequently featured in media reports as an exceptional example of marine pollution.
The JUNK Raft Project was a 2008 trans-Pacific sailing voyage made to highlight the plastic in the patch, organized by the Algalita Marine Research Foundation.
In 2009, two project vessels from Project Kaisei/Ocean Voyages Institute; the "New Horizon" and the "Kaisei", embarked on a voyage to research the patch and determine the feasibility of commercial scale collection and recycling. The Scripps Institute of Oceanography's 2009 SEAPLEX expedition in part funded by Ocean Voyages Institute/Project Kaisei also researched the patch. Researchers were also looking at the impact of plastic on mesopelagic fish, such as lanternfish.
In 2010, Ocean Voyages Institute conducted a 30-day expedition in the gyre which continued the science from the 2009 expeditions and tested prototype cleanup devices.
in July/August 2012 Ocean Voyages Institute conducted a voyage from San Francisco to the Eastern limits of the North Pacific Gyre north, (ultimately ending in Richmond British Columbia) and then made a return voyage which also visited the Gyre. The focus on this expedition was surveying the extent of tsunami debris from the Japanese earthquake-tsunami.
Mitigation.
At TEDxDelft2012, Boyan Slat unveiled a concept for removing large amounts of marine debris from oceanic gyres. Calling his project The Ocean Cleanup, he proposed to use surface currents to let debris drift to collection platforms. Operating costs would be relatively modest and the operation would be so efficient that it might even be profitable. The concept makes use of floating booms that divert rather than catch the debris. This avoids bycatch, while collecting even the smallest particles. According to Slat's calculations, a gyre could be cleaned up in five years' time, amounting to at least 7.25 million tons of plastic across all gyres. He also advocated "radical plastic pollution prevention methods" to prevent gyres from reforming. In 2015, The Ocean Cleanup project was a category winner in the Design Museum's 2015 Designs of the Year awards. A fleet of 30 vessels, including a 32-metre (105-foot) mothership, took part in a month-long voyage to determine how much plastic is present using trawls and aerial surveys.
The 2012 Algalita/5 Gyres Asia Pacific Expedition began in the Marshall Islands on 1 May, investigated the patch, collecting samples for the 5 Gyres Institute, Algalita Marine Research Foundation, and several other institutions, including NOAA, Scripps, IPRC and Woods Hole Oceanographic Institute. In 2012, the Sea Education Association (SEA) conducted research expeditions in the gyre. One hundred and eighteen net tows were conducted and nearly 70,000 pieces of plastic were counted.
In 2012, researchers Goldstein, Rosenberg and Cheng found that microplastic concentrations in the gyre had increased by two orders of magnitude in the prior four decades.
On 11 April 2013, artist Maria Cristina Finucci founded "The Garbage Patch State" at UNESCO – Paris in front of Director General Irina Bokova.
On 9 September 2018, the first collection system was deployed to the gyre to begin the collection task. This initial trial run of the Ocean Cleanup Project started towing its "Ocean Cleanup System 001" from San Francisco to a trial site some 240 nautical miles (260 miles) away.
In June 2019, Ocean Voyages Institute, the same organization behind the 2009, 2010 & 2012 expeditions, conducted a cleanup in the gyre and removed over 84,000 pounds of polymer nets and consumer plastic trash from the ocean.
In May/June 2020, Ocean Voyages Institute conducted a cleanup expedition in the Gyre which removed over 170 tons (340,000 pounds) of consumer plastics and ghostnets from the ocean Utilizing custom-designed GPS satellite trackers which are deployed by vessels of opportunity, Ocean Voyages Institute is able to accurately track and send cleanup vessels to remove ghostnets. The GPS Tracker technology is being combined with satellite imagery increasing the ability to locate plastic trash and ghostnets in real time via satellite imagery which will greatly increase cleanup capacity and efficiency.
Sources of the plastic.
In 2015, a study published in the journal "Science" sought to discover where exactly all of this garbage is coming from. According to the researchers, the discarded plastics and other debris floats eastward out of countries in Asia from six primary sources: China, Indonesia, the Philippines, Vietnam, Sri Lanka and Thailand. In fact, the Ocean Conservancy reported that China, Indonesia, Philippines, Thailand, and Vietnam dump more plastic in the sea than all other countries combined. China alone is responsible for 30% of worldwide plastic ocean pollution. Efforts to slow land generated debris and consequent marine debris accumulations have been undertaken by the Coastal Conservancy, Earth Day, and World Cleanup Day.
According to National Geographic, "About 54 percent of the debris in the Great Pacific Garbage Patch comes from land-based activities in North America and Asia. The remaining 20 percent of debris in the Great Pacific Garbage Patch comes from boaters, offshore oil rigs, and large cargo ships that dump or lose debris directly into the water. The majority of this debris—about 705,000 tons—is fishing nets."
In September 2019, when research revealed that much ocean plastic pollution comes from Chinese cargo ships. An Ocean Cleanup spokesperson said: "Everyone talks about saving the oceans by stopping using plastic bags, straws and single-use packaging. That's important, but when we head out on the ocean, that's not necessarily what we find."
A 2018 study found that at least 46% of the patch is composed of fishing nets.
Constitution.
The Great Pacific garbage patch formed gradually as a result of ocean or marine pollution gathered by ocean currents. It occupies a relatively stationary region of the North Pacific Ocean bounded by the North Pacific Gyre in the horse latitudes. The gyre's rotational pattern draws in waste material from across the North Pacific, incorporating coastal waters off North America and Japan. As the material is captured in the currents, wind-driven surface currents gradually move debris toward the center, trapping it.
In a 2014 study researchers sampled 1571 locations throughout the world's oceans, and determined that discarded fishing gear such as buoys, lines and nets accounted for more than 60% of the mass of plastic marine debris. According to a 2011 EPA report, "The primary source of marine debris is the improper waste disposal or management of trash and manufacturing products, including plastics (e.g., littering, illegal dumping) ... Debris is generated on land at marinas, ports, rivers, harbors, docks, and storm drains. Debris is generated at sea from fishing vessels, stationary platforms, and cargo ships." Constituents range in size from miles-long abandoned fishing nets to micro-pellets used in cosmetics and abrasive cleaners. A computer model predicts that a hypothetical piece of debris from the U.S. west coast would head for Asia, and return to the U.S. in six years; debris from the east coast of Asia would reach the U.S. in a year or less. While microplastics make up 94% of the estimated 1.8 trillion plastic pieces, they amount to only 8% of the 79,000 metric tons of plastic there, with most of the rest coming from the fishing industry.
A 2017 study concluded that of the 9.1 billion tons of plastic produced since 1950, close to 7 billion tons are no longer in use. The authors estimate that 9% was recycled, 12% was incinerated, and the remaining 5.5 billion tons remains in the oceans and land.
Size estimates.
The size of the patch is indefinite, as is the precise distribution of debris because large items are uncommon. Most debris consists of small plastic particles suspended at or just below the surface, evading detection by aircraft or satellite. Instead, the size of the patch is determined by sampling. Estimates of size range from (about the size of Texas) to more than (about the size of Russia). Such estimates, however, are conjectural given the complexities of sampling and the need to assess findings against other areas. Further, although the size of the patch is determined by a higher-than-normal degree of concentration of pelagic debris, there is no standard for determining the boundary between "normal" and "elevated" levels of pollutants to provide a firm estimate of the affected area.
In August 2009, the Scripps Institution of Oceanography/Project Kaisei SEAPLEX survey mission of the Gyre found that plastic debris was present in 100 consecutive samples taken at varying depths and net sizes along a path of through the patch. The survey found that, although the patch contains large pieces, it is on the whole made up of smaller items that increase in concentration toward the gyre's centre, and these 'confetti-like' pieces that are visible just beneath the surface suggests the affected area may be much smaller. 2009 data collected from Pacific albatross populations suggest the presence of two distinct debris zones.
In March 2018, The Ocean Cleanup published a paper summarizing their findings from the Mega- (2015) and Aerial Expedition (2016). In 2015, the organization crossed the Great Pacific garbage patch with 30 vessels, to make observations and take samples with 652 survey nets. They collected a total of 1.2 million pieces, which they counted and categorized into their respective size classes. In order to also account for the larger, but more rare debris, they also overflew the patch in 2016 with a C-130 Hercules aircraft, equipped with LiDAR sensors. The findings from the two expeditions, found that the patch covers 1.6 million square kilometers with a concentration of 10–100 kg per square kilometer. They estimate an 80,000 metric tons in the patch, with 1.8 trillion plastic pieces, out of which 92% of the mass is to be found in objects larger than 0.5 centimeters.
NOAA stated:
In a 2001 study, researchers found concentrations of plastic particles at 334,721 pieces per km2 with a mean mass of 5.1 kg (11.3 lbs) per km2, in the neuston. The overall concentration of plastics was seven times greater than the concentration of zooplankton in many of the sampled areas. Samples collected deeper in the water column found much lower concentrations of plastic particles (primarily monofilament fishing line pieces).
Effect on marine life and humans.
The United Nations Ocean Conference estimated that the oceans might contain more weight in plastics than fish by the year 2050. Some long-lasting plastics end up in the stomachs of marine animals. Plastic attracts seabirds and fish. When marine life consumes plastic allowing it to enter the food chain, this can lead to greater problems when species that have consumed plastic are then eaten by other predators.
Animals can also become trapped in plastic nets and rings, which can cause death. Plastic pollution affects at least 700 marine species, including sea turtles, seals and sea lions, seabirds, fish, and whales and dolphins. Cetaceans have been sighted within the patch, which poses entanglement and ingestion risks to animals using the Great Pacific garbage patch as a migration corridor or core habitat.
Affected species include sea turtles, the black-footed albatross, many species of whales, among many others. Midway Atoll receives substantial amounts of marine debris from the patch.Bioaccumulation of microplastics can have a huge affect on the food web, thus altering ecosystems and contributing to loss of biodiversity.
Direct harm to species.
Multiple studies have found plastics and microplastics in the stomach contents of marine animals.
Of the 1.5 million Laysan albatrosses that inhabit Midway Atoll, nearly all are likely to have plastic in their gastrointestinal tract. Approximately one-third of their chicks die, and many of those deaths are from plastic unwittingly fed to them by their parents. Twenty tons of plastic debris washes up on Midway every year with five tons ending up in the bellies of albatross chicks. Fish and whales may also mistake the plastic as a food source.
Plastics are ingested by various species of whales, such as beaked whales, baleen whales, and sperm whales. They can mistake plastics for food and consume them accidentally when feeding on prey organisms that are gathered near plastics. Plastics can also enter their system if their prey already had synthetic plastic particles in their digestive tract via bioaccumulation.
The ingestion of large amounts of plastic debris, such as fish nets and ropes, can lead to marine animal's deaths via gastric impaction. Microplastics can concentrate in the gills and intestines of marine life and can interfere with their feedings habits, typically resulting in death.
A study from 2019 indicates that the large amounts of plastic in the Great Pacific garbage patch could affect the behavior and distribution of some marine animals, as they can act as fish aggregating devices (FAD). FADs can attract feeding cetaceans, thus increasing the risk of being entangled or ingesting additional plastic.
Types of plastic.
There are various types of ocean plastics causing problems to marine life.
Bottle caps have been found in the stomachs of turtles and seabirds, which have died because of the obstruction of their respiratory and digestive tracts.
Ghostnets are also a problematic type of ocean plastic as they can continuously trap marine life in a process known as ‘ghost fishing.’
Health effects.
Plasticizers in microplastics have been linked to abnormal growth and reproductive problems in multiple animal models due to endocrine disruption. Microplastics have also been postulated to cause GI irritation, alteration of the microbiome, disturbance of energy and lipid metabolism, and oxidative stress.
Organic pollutants, such as pesticides, can leach into organisms that ingest microplastics, along with dangerous metals such as lead and cadmium.
Direct harm to humans.
Ingestion of plastics has been associated with a variety of reproductive, carcinogenic, and mutagenic effects. The most wellknown organic synthetic compound used in many plastics is bisphenol A (BPA). It has been linked with autoimmune disease and endocrine disrupting agents, leading to reduced male fertility and breast carcinogenesis. Plastics in the human system can cause inhibition of organismal detoxification mechanisms causing acute toxicity and lethality.
Nanoplastics are able to overcome the intestine tissue in aquatic systems and have the possibility to end up in the human food chain by inhalation or ingestion, particularly through shellfish and crustaceans. They have the potential to affect the central nervous system and reproductive system, although this would be unlikely unless exposure levels were very high and absorption levels were increased. In vitro studies from human cells showed evidence that polystyrene nanoparticles are taken up and can induce oxidative stress and pro-inflammatory responses.
References.
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Further reading