Ocean Pollution's Climate Change Impact: A Complex Connection

Marine pollution and the climate crisis are often viewed as separate issues, but they are fundamentally linked. The production, use, and disposal of plastic create significant greenhouse gas emissions that cause climate change. As plastic breaks down, it releases methane and ethylene—and the smaller the pieces, the more gases are produced. This not only harms marine life but also interferes with the ocean's ability to absorb and sequester carbon dioxide, creating another pathway for plastic pollution to accelerate climate change.

Plastic production increases fossil fuel use and our carbon footprint

Plastic production is closely linked to the fossil fuel industry. As 99% of plastics are made from fossil fuels, the production of plastics is a significant driver of climate change. The more plastic we produce, the more fossil fuels we use, and the larger our carbon footprint becomes.

The extraction, refining, and manufacture of plastics are all carbon-intensive activities. The production of plastic involves the conversion of fossil fuels into plastics, which is a greenhouse gas-emitting process. In 2015, CO2 and other GHG emissions from plastic production reached 1.96 Gt of CO2e, for a cost of $341 billion annually. The CIEL report estimates that 12.5 to 13.5 million metric tons of carbon dioxide equivalent are emitted per year while extracting and transporting natural gas to create feedstocks for plastics in the United States.

The refining and manufacturing of plastics are also greenhouse-gas intensive processes. In 2015, emissions from manufacturing ethylene, the building block for polyethylene plastics, were 184.3 to 213 million metric tons of carbon dioxide equivalent. Globally, carbon dioxide emissions from ethylene production are projected to expand by 34% between 2015 and 2030.

The disposal of plastic waste also contributes to greenhouse gas emissions. Incineration of plastic waste releases significant GHGs into the atmosphere, along with toxic pollutants. Other disposal methods, such as recycling, also result in GHG emissions.

The global plastic industry is largely fueled by natural gas, and its rapid growth undermines efforts to reduce carbon pollution and prevent a climate catastrophe. Estimates indicate that GHG emissions from plastics could reach about 13% of the entire remaining carbon budget by 2050. If we continue to increase plastic production, we will not only use more fossil fuels but also accelerate climate change.

Marine life is harmed by plastic pollution, which also affects human health

Marine life is extremely vulnerable to plastic pollution, which has devastating effects on ocean ecosystems. Plastic waste in the ocean harms marine wildlife in several ways, including entanglement, injury, ingestion, and toxic contamination. Large plastic items, such as discarded fishing gear, ropes, nets, and six-pack rings, can trap and entangle marine mammals and fish, leading to starvation, injury, and increased vulnerability to predators. For example, an estimated 300,000 whales, dolphins, and porpoises die each year from entanglement in ghost gear. Plastic debris also smothers and damages coral reefs, preventing their healthy growth.

Smaller plastic fragments, ranging from 5 to 10 mm in size, can float on the water surface and be mistaken for food by seabirds and other marine species. This leads to suffocation, starvation, and toxic contamination as the plastic accumulates in their bodies. Microplastics, measuring less than 5 mm, are invisible to the naked eye, making it even easier for marine organisms to consume them. These microscopic particles can adsorb toxins, which then transfer to the fatty tissues of the organisms that ingest them. As a result, the long-term impacts of microplastics on marine life are a growing concern.

The impact of plastic pollution on marine life also extends to humans. Microplastics have been detected in seafood, and their presence in the food chain poses risks to human health. Additionally, the ingestion of plastics by marine organisms can lead to the transfer of toxic chemicals up the food chain through bioaccumulation. This process results in higher concentrations of toxins in apex predators and species higher up the food chain, such as orcas and great white sharks.

Furthermore, plastic pollution contributes to climate change, which further exacerbates the harm to marine life and human health. As plastic degrades, it emits greenhouse gases, including methane and carbon dioxide. The production, processing, and transportation of plastic also contribute to greenhouse gas emissions. The combination of plastic pollution and climate change creates a vicious cycle that poses significant threats to biodiversity, ecosystems, and human well-being.

Greenhouse gases are released during plastic degradation in the ocean

Plastic pollution is a significant problem with a detrimental impact on the environment and climate change. The degradation of plastic materials in the ocean increases CH4 and CO2 emissions, contributing to the greenhouse effect and global warming.

Research has shown that when exposed to sunlight, common plastics such as polyethylene, polypropylene, and polystyrene, among others, release methane and ethylene, which are greenhouse gases. The more plastic breaks down into smaller pieces, the more greenhouse gases are produced. This process of degradation occurs through four mechanisms: thermo-oxidative degradation, hydrolytic degradation, and biodegradation by microorganisms, and photodegradation.

The consequences of plastic pollution in the ocean go beyond the immediate damage visible to the naked eye, such as the entanglement and ingestion of plastic debris by marine wildlife. The degradation of plastics impacts the balance of ecosystems, the fauna and flora, and human health.

Furthermore, the production of plastic is closely linked to the fossil fuel industry. As we increase plastic production, we also increase our use of fossil fuels and our carbon footprint. This contributes to the climate emergency and further increases environmental pressure.

The fight against plastic pollution is one of the most significant challenges of our century. To address this crisis, it is imperative to reduce plastic production at the source and transition to a circular economy that reuses, refills, and repairs items instead of discarding them.

The ocean's ability to absorb carbon dioxide is hindered by plastic pollution

The ocean is the world's greatest ally in the fight against climate change. It absorbs 25% of all carbon dioxide emissions and captures 90% of the excess heat generated by these emissions. It is not just the lungs of the planet but also its largest carbon sink, a vital buffer against the impacts of climate change.

However, plastic pollution is a significant threat to the ocean's ability to absorb carbon dioxide. The staggering amounts of plastic waste entering the ocean are having a detrimental effect on its capacity to act as a carbon sink. Plastic waste in the ocean is negatively impacting its role as a natural carbon sink, and urgent action is needed to address this crisis.

One way plastic hinders the ocean's ability to absorb carbon dioxide is by making phytoplankton excretion more buoyant. Phytoplankton is a type of algae that captures carbon from the atmosphere and releases oxygen. Normally, when phytoplankton excrete carbon, it sinks to the ocean floor and stays captured there due to the pressure of the ocean's weight. However, plastic makes phytoplankton excretion more buoyant, causing it to float more and sink slower, giving carbon more time to escape back into the atmosphere.

Additionally, plastic poses a lethal threat to whales, which are crucial for carbon capture. Whales store a large amount of CO2 during their lifespan, and when they die, they sink to the ocean floor, trapping carbon for hundreds of years. Plastic endangers whales through ingestion, entanglement, and the build-up of pollutants. If whales are dying prematurely due to plastic pollution, they are capturing less carbon.

Furthermore, a study in 2018 revealed that plastic debris, when exposed to sunlight, releases carbon. As plastic breaks down into smaller pieces, it produces more greenhouse gases, including methane and CO2. This directly contributes to the increase in greenhouse gas concentrations in the atmosphere, exacerbating global warming.

The fight against plastic pollution is critical in preserving the ocean's ability to act as a carbon sink and mitigating the impacts of climate change. Reducing the use of single-use plastics and transitioning to a circular economy are essential steps in tackling this global crisis.

Open burning of plastic waste is a significant source of air pollution

Marine pollution and climate change are fundamentally linked. As 99% of plastics are made from fossil fuels, plastic pollution is linked to climate change. The production, manufacturing, use, recycling, and disposal of plastics all negatively impact the environment and human health.

The open burning of plastic waste is a significant source of air pollution and is common across the globe, especially in places with inadequate waste management services. This practice is highly toxic to human and environmental health, releasing gas emissions and ash residues containing harmful chemicals such as microplastics, bisphenols, and phthalates, carbon monoxide, dioxins, chlorinated furans, styrene gas, and heavy metals. These toxins can remain in the environment long after the smoke and smell of burning plastic have dissipated, contaminating the soil, groundwater, and surrounding food chains.

The effects of open burning are far-reaching, with plastic burning contributing to air pollution, which is the single largest risk factor for ill health globally. It is estimated that outdoor air pollution contributed to nearly 7 million premature deaths in 2019. The toxins released during plastic burning can cause a range of health issues, including neurodevelopmental, endocrine, and reproductive problems, as well as an increased risk of heart disease, respiratory issues, and neurological disorders.

Despite the existence of regulations and laws against open burning in many countries, these practices continue due to a lack of awareness about the harms, limited waste management alternatives, and the shipping of plastic waste from high-income countries to low- and middle-income nations. To address this issue, interventions should focus on raising awareness about the risks, improving waste management infrastructure, and shifting the responsibility for plastic disposal from consumers to the plastic industry and consumer goods companies.

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