Updated: Jan 21
Plastic exacerbate climate change and global warming at every stage of its lifecycle. In its recent report the Center for International Environmental Law (CIEL) warns that plastic emits greenhouse gases into the atmosphere at its four stages of existence: extraction and transportation of fossil fuels, which almost all plastics originates from, refining and manufacture, waste management and degradation in natural environments. Overall, plastic is responsible for 3.8% of global greenhouse gas emissions. That’s almost double the emissions of the aviation sector. If it were a country, plastic would be the fifth-highest emitter in the world.
In 2019, the production and burning of plastics produced around 850 million metric tons of greenhouse gases which equates to the emissions from 189 five-hundred megawatt coal power plants. With the responsible industries planning a massive expansion in plastics production, the situation is predicted to get much worse threatening our ability to keep global temperatures below 1.5°C threshold. By 2050, annual emissions could grow to nearly 2.8 billion metric tons of CO2 which is similar to running 615 coal plants.
This blog post is a short description of all the four stages of plastic lifecycle - we hope that it will help you to understand how exactly it drives climate change.
How plastic is born: fossil fuels extraction and transportation
According to the World Economic Forum, currently plastics production accounts for up to 8% of annual global oil consumption. With the plastic and petrochemical industries planning a significant expansion it is predicted that by 2050 this number will grow to 20 percent!
During the first stage of plastic life when fossil fuels (mainly oil, but also gas and coal) have to be extracted and transported, approximately 120 million metric tons of CO2 equivalents (CO2e) are emitted each year worldwide. To compare, between September 2019 and January 2020 Australian bushfires released around 400 million metric tons of carbon dioxide into the atmosphere.
Extraction of fossil fuels is not the only carbon-intensive activity during this stage of plastic life. Associated with it deforestation equally contributes to climate change. Since fossil fuels extraction requires the surrounding land to be cleared, destroyed forests that normally serve the role of Earth’s carbon sinks are releasing carbon back into the atmosphere.
Finally, after being extracted fossil fuels need to be transported to other facilities by trains and trucks, or via pipelines, which contribute to carbon emissions even further.
Giving plastic its shape: refining and manufacture
After extraction, petrochemicals that are used for production of over 99% of plastics are getting refined to build ethylene, butene, propylene, and other basic plastic building blocks which are then transported to manufacturers. The production and transportation of these resins requires high amounts of energy - it is estimated that over 60% of total plastic greenhouse gas emissions comes from the refining stage of plastics lifecycle together with its transportation to the manufacturers.
During the manufacturing process plastics emit another 30% of greenhouse gasses - mainly because of the energy required to power the plants that transforms raw plastic materials into ready-to-sell plastic goods.
Discarding plastic: waste management
At the end of its lifecycle plastics is either incinerated, recycled or buried in landfill. According to CIEL report, plastics incineration emits the most greenhouse gases. For example, global emissions from incineration of plastic packaging which represents 40 percent of plastic out there totalled 16 million metric tons of CO2e in 2015. This number does not include 32 percent of plastic packaging waste that is unmanaged, incineration that occurs without any energy recovery and open burning of plastic.
The prospects for the future are not that shiny: WWF Global predicts that by 2030 carbon dioxide emissions from plastic waste management could triple.
In Australia, 87% of generated plastic waste goes to landfill, only 12% of it is recycled and the remaining 1% is sent to an energy from waste facility.
End of lifecycle: plastic in the environment
Some of plastic waste is not managed properly - it’s left uncollected, being openly dumped, littered, or managed through unregulated landfill. As a result, globally one-third of plastic waste has entered nature as land, freshwater or marine pollution.
Annually, at least 8 million tonnes of plastic rubbish finds its way into oceans covering every square kilometre with 13,000 pieces of differently sized plastic particles. Plastic has even been discovered in the Marina Trench, the deepest place on Earth located 11 kilometres below sea level.
Oceans polluted by plastic waste accelerate climate change and global warming in two ways. Firstly, similar to trees world oceans are serving as the largest natural carbon sinks for greenhouse gases - it is estimated that since the dawn of the industrial era they have absorbed 20-40 percent of all anthropogenic carbon emissions. The key role in this process is played by microscopic plants (phytoplankton) and animals (zooplankton) that capture carbon at the ocean’s surface and transport it into oceans’ deep layers preventing it from reentering the atmosphere. Presence of plastic in the form of micro particles directly threatens the wellbeing of both photo-and zooplankton influencing their metabolic rates, reproductive success, and survival in general. Reduced number of plankton in oceans and its compromised ability to remove carbon means that higher volume of carbon stays in the atmosphere directly contributing to climate change and global warming.
In addition, recent research study has found that as plastic degrades during exposure to sunlight and in water, it releases methane and ethylene, with methane being one of the most potent atmospheric greenhouse gases. To make things worse, the emissions increase over time as plastic breaks down into smaller particles - the bigger surface area covered in plastic particles releases more gases. These emissions continue for an undetermined period since plastic never degrades completely. The same study found that the biggest culprit among all the plastic types is low-density polyethylene (LDPE), the material used to make single-use plastic bags including single-use plastic garbage bags.
Since its mass production in the 1950s plastic has became an integral part of our everyday lives. It makes everything so much easier, but at the same time it threatens our own existence through it’s significant contribution to climate change. Many businesses justify the increasing volumes of manufactured plastics by the growing demand from consumers, but is this really the case? With nine in 10 Australians being concerned about sustainability, it seems that it’s time to shift the demand from single-use plastics to its green alternatives. Start making conscious choices as a consumer - refuse single-use plastics and start reusing it where possible.