Plastics have an interesting and complex relationship with climate change and rising greenhouse gases.
99% of plastics come from fossil fuels and throughout its life cycle it makes a significant contribution to rising greenhouse gases and climate change. Plastic pollutes at every stage; from materials extraction, product production and transportation to disposal.
Plastics currently account for around 6% of global oil demand and are responsible for rising methane emissions from associated gas extraction. Once the materials have been extracted there are then the carbon emissions from production and transportation of plastic. Its been estimated that one 500ml plastic water bottle (about 10 grams) has an average total CO2 footprint of 82.8 grams. For context, the production of four plastic bottles produces approximately the same amount of greenhouse gas emissions as travelling one mile in a medium-sized petrol car.
But the story doesn’t end there, a study by the University of Hawaii has demonstrated that many plastics also give off powerful greenhouse gases as they breakdown, which is also contributing to climate change. Of particular concern is LDPE which releases gases at the highest rate and is also the most prevalent discarded plastic in oceans. Its been discovered that the more surface area a piece of plastic has the more gas is given off. So for example a plastic bottle, after years of photodegradation in the ocean will have a surface area thousands of times greater than its original surface area, leading to a greater emission of methane. This means that over time plastics give off more and more harmful gas and are further adding to climate change.
With around half of all plastic production being destined for a single-use item this seems like a terrible use of a limited natural resource and an extremely wasteful addition to greenhouse gases. With around 8 million tonnes of plastic ending up in the oceans each year this massively adds to the greenhouse gas problem as it slowly breaks down in the environment and starts to release harmful greenhouse gases.
Moving away from single-use plastic will help tackle carbon emissions from both ends. Scarily plastic production is currently expected to triple by 2050 and its predicted that the plastic industry will be accounting for 15% of global greenhouse gas emissions. This is something we can reduce and do something about. By reusing what we’ve already got and moving away from single-use, we’ll move to a more circular economy that will help reduce carbon emissions.