Pacific Ocean: A Plastic Pollution Crisis

The Pacific Ocean is being polluted by plastic waste at an alarming rate. The Great Pacific Garbage Patch, located between Hawaii and California, is the largest accumulation of plastic in the open ocean. It is estimated to contain 79,000 to 100,000 metric tons of plastic waste, comprising 1.8 trillion pieces of trash. This plastic pollution is not only detrimental to marine life but also has economic implications, affecting fisheries, coastlines, tourism, and the food we eat. Various organizations are attempting to address this issue, but the solution lies in reducing plastic production and improving waste management and recycling infrastructure.

The Great Pacific Garbage Patch

The GPGP is one of five offshore plastic accumulation zones in the world's oceans. It is estimated that 1.15 to 2.41 million tonnes of plastic enter the ocean each year from rivers, with more than half of this plastic being less dense than water, allowing it to persist on the sea surface. The plastic is transported by converging currents and accumulates in the patch. The GPGP covers an estimated 1.6 million square kilometres, an area twice the size of Texas or three times the size of France.

The patch is comprised of the Western Garbage Patch, located near Japan, and the Eastern Garbage Patch, located between Hawaii and California. These areas of spinning debris are linked by the North Pacific Subtropical Convergence Zone, located a few hundred kilometres north of Hawaii. The circular motion of the gyre draws debris into its stable centre, where it becomes trapped. For example, a plastic bottle discarded off the coast of California may be carried south by the California Current, then caught by the North Equatorial Current, which crosses the Pacific. Near Japan, the bottle may be carried north by the Kuroshio Current, before travelling east on the North Pacific Current. The bottle would then be drawn into the Eastern and Western Garbage Patches.

Plastic waste in the ocean food chain

The Great Pacific Garbage Patch (GPGP) is the largest accumulation of plastic in the open ocean, located between Hawaii and California. It is one of five offshore plastic accumulation zones in the world's oceans. The GPGP is a gyre of marine debris particles, with plastic making up 99.9% of this debris. It is estimated that the patch covers 1.6 million square kilometres, with a concentration of 10-100 kilograms of plastic per square kilometre. This amounts to roughly 79,000-80,000 metric tons of plastic, or 1.8 trillion pieces of plastic trash.

The GPGP is a significant contributor to plastic waste in the ocean food chain. Plastic waste in the ocean can have detrimental effects on marine life and, subsequently, on human health. Marine organisms, such as fish and birds, ingest plastic, mistaking it for food. This ingestion can lead to reduced fitness, nutrient uptake, and feeding efficiency, posing life-threatening consequences for these animals. Furthermore, plastic waste can act as a magnet for toxins from the surrounding environment, increasing the toxicity of ingested plastic over time. As these toxins bioaccumulate in the food chain, they can eventually reach humans who consume contaminated seafood.

The impact of plastic waste in the ocean food chain extends beyond direct ingestion. Floating plastic debris can facilitate the spread of coastal organisms into new environments, disrupting the delicate balance of marine ecosystems. This can have adverse effects on native species, such as neuston, and contribute to the overall decline in fish populations. For example, tuna populations have declined by 74% since 1970, raising concerns about the future availability of seafood.

To address the issue of plastic waste in the ocean food chain, it is crucial to focus on waste management and reduction. Currently, only 9% of plastic waste is recycled globally, while 22% is not collected, improperly disposed of, or becomes litter. Improving waste management practices, particularly in rapidly growing economies with increasing disposable plastic usage, is essential to preventing plastic from entering the ocean. Additionally, individuals can play a role by reducing their plastic consumption, reusing and recycling plastic products, and supporting organisations dedicated to ocean conservation and cleanup efforts.

While the Great Pacific Garbage Patch may be the most well-known accumulation of plastic in the ocean, it is important to recognise that plastic pollution is a global issue. Plastic waste enters the ocean from thousands of sources worldwide, and it is estimated that 8-11 million metric tons of plastic are dumped into the ocean annually. This continuous influx of plastic waste into marine ecosystems underlines the urgency of addressing the problem through a combination of improved waste management, reduced plastic production and consumption, and the development of sustainable alternatives.

Marine animals dying from plastic debris

Marine animals are suffering and dying from plastic pollution in the Pacific Ocean. The Great Pacific Garbage Patch, located between Hawaii and California, is the largest accumulation of ocean plastic globally. It is estimated to contain 79,000-80,000 metric tons of plastic, with 1.8 trillion pieces of trash, 99.9% of which is plastic. This plastic pollution does not form giant islands of floating garbage, as commonly believed, but instead consists of microscopic particles dispersed in the upper water column. These microplastics can be deadly for marine life.

Plastic pollution affects at least 700 marine species, and some estimates suggest that at least 100 million marine mammals are killed each year. Marine mammals, such as whales, sea lions, and dolphins, can become entangled in plastic debris, leading to severe injuries and infections. They may also mistake plastic waste for food, causing blockages and obstructions in their digestive systems. For example, a juvenile sperm whale died after ingesting nearly 30 kilograms of plastic, causing fatal inflammation.

Sea turtles are also severely impacted by plastic pollution. Studies show that up to 50% of sea turtles are ingesting plastic, and all seven sea turtle species are affected. Plastic debris can obstruct their digestive systems and cause internal punctures, leading to death. Additionally, marine birds, such as the Laysan albatross, are deeply affected by plastic pollution, with 98% of studied birds found to have ingested plastic debris.

The impact of plastic pollution on marine life is devastating and widespread. It is important to address this issue through education, recycling, and participation in beach clean-up efforts to reduce the amount of plastic entering the ocean and mitigate its harmful effects on marine animals.

Plastic removal technologies

The Great Pacific Garbage Patch, located between Hawaii and California, is the largest accumulation of ocean plastic in the world. It is estimated that there are 79,000-88,000 metric tons of plastic in this area, with 1.8 trillion plastic pieces making up 99.9% of the debris.

Various technologies and strategies are being developed and deployed to address the issue of plastic pollution in the Pacific Ocean and other aquatic environments. Here are some key approaches:

• River Interception Technologies: The Ocean Cleanup, a non-profit organization, has developed river interception technologies called "Interceptors." These are solar-powered catamaran-like vessels placed at the mouths of polluted rivers. As the water flows, trash is guided by a barrier onto a conveyor belt, which dumps it into a shuttle. The shuttle then transports the trash to dumpsters on a barge, which are emptied at a waste management facility. This technology has successfully removed over 2.2 million pounds of trash from rivers in several countries.
• Ocean Cleanup Systems: The Ocean Cleanup is also working on ocean cleanup systems to address plastic pollution that has already accumulated in the ocean. Their system consists of a large floating net-like barrier with a U-shaped design that is towed by two ships. The natural flow of the water directs the plastic to a central retention zone. The retention zone is regularly emptied, and the plastic is separated, packaged, and sent to recycling facilities onshore.
• Hydrographic Modelling and Remote Sensing: Hydrographic modelling studies use environmental monitoring data and ocean circulation patterns to predict the spatial distribution of plastic litter. Remote sensing technologies such as satellites, drones, sensors on boats, underwater cameras, and unmanned vehicles are also used to identify pathways, fluxes, and accumulation areas for plastic debris. Machine learning and artificial intelligence further enhance the analysis and identification of litter in the environment.
• Prevention and Policy: While cleanup technologies are crucial, prevention is key to tackling plastic pollution. The "waste hierarchy" emphasizes that preventing plastic from entering the environment must be a policy priority. Governments worldwide are negotiating the United Nations (UN) Plastics Treaty, which includes potential obligations for member states to monitor plastic pollution, adopt effective mitigation measures, and engage in clean-up activities.

While these technologies and strategies offer promising solutions, it is important to note that most technologies are plastic-type or context-specific, and their efficiency, cost, and environmental impact may vary. Additionally, microplastics, due to their small size and widespread dispersion, pose a significant challenge for removal.

Efforts to clean up ocean plastic

The Great Pacific Garbage Patch (GPGP) is the largest accumulation of ocean plastic in the world, located between Hawaii and California. It is estimated that roughly 79,000 to 80,000 metric tons of plastic are floating inside the GPGP, which is around 1.8 trillion pieces of trash.

Various efforts are being made to clean up ocean plastic, including:

• The Ocean Cleanup: This non-profit organization is one of the most well-known and well-funded efforts, aiming to remove 90% of floating plastic by 2040 using ocean cleanup systems and river interception technologies. Their current system consists of a large floating net-like barrier that forms a U-shape and is towed by two ships, directing plastic to a central retention zone. While this system has been successful in removing 220,000 pounds of plastic from the GPGP, some marine biologists have criticized it for its potential harm to marine life and carbon dioxide emissions.
• The JUNK Raft Project: Organized by the Algalita Marine Research Foundation, this project was a 2008 trans-Pacific sailing voyage that aimed to highlight the plastic in the patch.
• Project Kaisei/Ocean Voyages Institute: In 2009, two project vessels, the New Horizon and the Kaisei, embarked on a voyage to research the patch and determine the feasibility of commercial-scale collection and recycling.
• Scripps Institute of Oceanography's SEAPLEX expedition: Partly funded by Ocean Voyages Institute/Project Kaisei, this expedition also researched the patch and the impact of plastic on mesopelagic fish.
• Local initiatives: Various local initiatives are also contributing to ocean plastic cleanup. For example, a Korean program pays fishermen to collect plastic at sea, and in Baltimore, Maryland, a trash wheel skims up to 17 tons of garbage out of the city's harbor daily.

While these efforts are commendable, it is important to recognize that the vast majority of plastic in the ocean is too small or too out of reach to be cleaned up. Thus, the real solution lies in systemic change, such as reducing single-use plastics, promoting recycling, and fostering sustainable practices.

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