How often has someone responded to your expression of concerns about climate change with the declaration that they recycle paper, plastic, glass, or metal? Do they think that solid waste drives climate change? (In reality, it’s almost all from greenhouse gases!)
This misconception begs the question: if everyone recycled everything they used, how much difference would it make for climate?
Let’s start with plastic, since it’s made from hydrocarbons, which ultimately convert to carbon dioxide when plastic is burned or otherwise oxidized. There are also emissions of methane and carbon dioxide during the extraction and transportation of crude oil and its conversion to plastic, estimated to be more than eight times the emissions after the plastic has been discarded.
So, recycling or reusing plastic reduces greenhouse gas emissions primarily if it reduces how much plastic is produced. Reusing plastic is always better than recycling it, because recycling requires additional energy that is usually produced by burning fossil fuels.
But even if we could eliminate all plastics, it would only reduce global greenhouse gas emissions by 3.3%. That’s not nothing, but we are very far from eliminating plastics. It’s far easier to produce plastics from petroleum than from plastic. Indeed, in the United States, only 6% of plastic is currently recycled. Other materials can be substituted for plastic, but they can have adverse effects as well.
There are other reasons to use less plastic, of course: microplastics might be hazardous to the health of people and animals, add to the enormous volume of landfills, and are a visual blight on the environment. So, yes, recycle and — better yet — reuse plastics. But don’t do it thinking those actions are effective in reducing global warming.
According to EnergyStar, greenhouse gas emissions from the production of paper and pulp comprises 2% of total U.S. greenhouse gas emissions. That could be reduced with more recycling, but it could only reduce U.S. emissions by 2% at most. The primary benefit is in the reduction in the number of trees consumed. However, most paper is made from industrial tree farms. That land could be applied to more beneficial uses, including diverse forests that provide habitat and continue to sequester carbon from the atmosphere. But even if all paper is perpetually recycled and sequestering forests are grown at the same rate as the trees grown for paper, the carbon stored would remove only 2% of the carbon emitted in the U.S.
For glass containers, U.S. emissions are now only 0.15% of total U.S. greenhouse gas emissions after decreasing fourfold between 1930 and 2010. Further reductions are unlikely. Since glass is made from sand, the primary benefit of recycling glass is reduction in litter and landfill.
Emissions from metal production are larger, contributing about 4.5% of U.S. greenhouse gas emissions. The vast majority of that is iron and steel used in buildings, bridges and vehicles. Emissions from the production of steel, aluminum and copper are 7%, 2%, and 0.2% of total global emissions, respectively. These metals are easily recycled and must be since the supply of their raw materials is increasingly scarce. But the fraction of global emissions associated with metal packaging such as cans is likely less than 1%.
So, recycling everything we use could reduce greenhouse gas emissions by 5% at most.
If recycling makes such a small difference in greenhouse gas emissions, what will make a larger difference? It’s simple; 75% of global greenhouse gas emissions are from burning fossil fuels for energy. A sixth of that energy is used to produce plastic, paper, glass, and metal. Half of that 75% is from transportation and heating. Since we know how to transport and heat without carbon emissions, focusing on that will be much more effective.
What you can do
If you want to reduce waste, reuse containers as much as is practical. Buy products in bulk and put them in reused containers. Reusing plastic containers is far more effective than recycling, and better for glass, too, because of the high heat required to recycle glass. Repairing items is also an important element of a circular economy.
If you want to save our climate for future generations, start by reducing your carbon footprint. If you have the resources, prioritize living near schools, jobs, and services so you can walk or ride your bike to school or work rather than drive. Similarly, purchasing an electric vehicle when your current vehicle is beyond repair, limiting your flying, opting for a heat pump when it’s time to replace your gas furnace or water heater, and reducing the amount of beef, dairy, and lamb that you eat are all effective ways to reduce your footprint. Don’t assume that carbon offsets or credits to compensate for your emissions are effective — trees wither and burn.
To amplify your impact on global emissions, advocate for policies that drive down emissions, like a price on carbon with revenue returned to people in equal shares, and energy permit reform to expand our electrical distribution system. You can amplify your voice by joining organizations such as Citizens Climate Lobby.
Climate scientist Steve Ghan leads the Tri-Cities Chapter of Citizens Climate Lobby.
