Zero Waste is one of the quickest, easiest and most effective first steps for a community to immediately reduce its GHG emissions.
When biodegradable materials such as paper products, food scraps and yard trimming are tossed in the garbage and sent to a landfill, those lettuce heads, grass clippings and paper boxes don’t just break down as they would in nature or in a compost pile. They decompose anaerobically, or without oxygen, and in the process create methane, a greenhouse gas (GHG). Methane is 72 times more potent than CO2 over a 20-year period—this means every one ton of methane will trap as much heat in our atmosphere as 72 tons of carbon dioxide! Landfills are a top source of methane, and one that could be easily avoided if we stopped landfilling organic materials and started composting them instead.
Methane is often cited as 21 times more potent than CO2, and this is also true, but this refers to methane's impact when measured over 100 years. The Intergovernmental Panel on Climate Change (IPCC) calculates the impact of GHG emissions based on three timeframes: 20 years, 100 years and 500 years. Which timeframe a community or a nation chooses to use is a policy decision based on whether they want to emphasize the short or long term. At the Kyoto Protocol, the 100-year timeframe was chosen as the international baseline because climate change was seen as a longer-term threat. Fifteen years later, our climate situation is more dire and immediate than we thought. Now we must cut emissions 80% by 2050, if not significantly sooner. Now we need data to emphasize the short-term impacts of our emissions so we can prioritize reductions to powerful, short-lived gases like methane. We need to look at the impacts of our emissions over the next 20 years if we are going to avoid runaway climate change.
(Source:IPCC, 2007. "Climate Change 2007: The Physical Science Basis, Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change." Chapter 2: Changes in Atmospheric Constituents and in Radiative Forcing.)
Methane only stays in the atmosphere around 8-12 years while carbon dioxide can last for centuries. But methane has a big effect in its short time—methane is responsible for 75% as much warming as carbon dioxide measured over any given 20 years (Watson, 2009). This means methane reductions could have an immediate beneficial effect on our climate, faster than comparable reductions to CO2.
Climate change is happening at an alarming rate. Leading nations are calling for emissions reductions of 80% by 2050 and others are saying we need to reduce emissions much sooner. This means we only have a few decades to act, so we need to concentrate on greenhouse gas reductions that will have an immediate impact. Our short-term climate actions should focus on reducing methane emissions so we can see the quickest benefit.
Compared to the massive requirements necessary to reduce CO2, cutting methane requires only modest investment. Where we stop methane emissions, cooling follows within a decade, not centuries. That could make the difference for many fragile systems on the brink.”
-- Robert Watson, former IPCC chair, “A Fast, Cheap Way to Cool the Planet.” Wall Street Journal, December 28, 2009.
When the EPA calculates greenhouse gas emissions from waste for our national GHG inventory, they only look at the emissions from landfills and incinerators. But waste isn’t just what happens after you discarded the product—where are the emissions from all the energy and materials used to extract, process and deliver that product to you?
Figure 1 (left) shows the traditional sector-based view of GHG emissions found in our national GHG inventory. Waste isn’t even represented on this chart, which means climate action plans are focusing primarily on reducing transportation and electricity emissions. The emissions from the energy and materials used to extract, process and deliver products to you, those products that then become trash, are embedded into categories like electric power, transportation, and industry.
Figure 2 (right) looks at our emissions from a system-based perspective and shows the way we produce, consume and dispose of our goods and food accounts for 42% of our nation’s greenhouse gas emissions. This means the choices we make about our “stuff” has a bigger impact than driving our car or heating our homes. This new approach is called materials management, and it’s defined by the EPA as “how we manage material resources as they flow through the economy, from extraction of materials and food, production, transport, provision of services, reuse of materials and, if necessary, disposal.” By using this approach to measure our greenhouse gas emissions, we can see the huge impact we can have by recycling more, expanding composting programs, and consuming less. Read the EPA report here.
This doesn’t mean reducing energy use, investing in renewable energy, or changing our transportation habits and technologies aren’t critical—they are! We need to reduce all our emissions substantially over the next few decades, but we haven’t been using all the tools we have to do this, and Zero Waste is an especially important tool because methane is such a powerful short-term gas.
(Chart created by Eco-Cycle based on "Opportunities to Reduce Greenhouse Gas Emissions through Materials and Land Management Practices,” U.S. EPA, 2009.)
When a local community calculates its greenhouse gas emissions from waste, it uses the First Order Decay (FOD) model for landfills (following IPCC protocol). This model measures only methane emissions that take place within the city limits within a given year. Any greenhouse gas emissions or savings from recycling or composting are not included in this approach, and neither are any emissions that occur outside of the city’s boundaries.
The EPA’s Waste Reduction Model (WARM) calculates the lifecycle GHG emissions from how we manage materials, not just how we manage waste. This accounts for the energy savings from recycling and composting, as well as landfill emissions. Using WARM to calculate emissions from materials management shows the substantial climate benefits from recycling and composting.
Here’s an example of how the two models can give you two different results:
The IPCC FOD model tells us metals disposed in a landfill emit 0 tons of methane because they’re not biodegradable. This means:
--> If you landfilled 100% of your metals, your local community GHG inventory would increase by 0.
--> If you recycled 100% of your metals, your local community GHG inventory would decrease by 0.
The EPA's WARM tells us recycling metals can save greenhouse gas emissions because it takes less energy to make new metal products from recycled metal than it does to use virgin metal. For example, recycling an aluminum can saves 95% of the energy used to make the can. In fact, WARM calculates that recycling 90% of U.S. metals could save 101 million mtCO2e annually, the equivalent to taking 19.3 million cars off the road for a year!
(Calculated by Eco-Cycle using EPA's “Municipal Solid Waste Generation, Recycling, and Disposal in the United States Detailed Tables and Figures for 2008,” WARM online calculator version 10 with default landfill gas recovery and distances, and EPA's online Greenhouse Gas Equivalencies Calculator.)
Local communities are missing the connection between their materials management choices and the climate because they’re focused only on the methane emissions from their local landfill. We all share one climate so emissions anywhere will affect all of us. This means we need to make decisions that reduce the greatest amount of GHG emissions, regardless of whether they occur at our local landfill or in a tropical forest across the globe. Local communities need to use WARM to make the right decisions about materials management so they see the total climate impact of their local actions.
1. Get involved with your community climate action plan. Promote recycling and composting as a proven, short-term strategy to reduce greenhouse gas emissions.
2. Calculate your local emissions based on their 20-year climate impact. Highlight the potency of methane. Contact us to learn how easy it is.
3. Use EPA’s WARM to estimate the total climate impact of recycling, composting and waste. Learn more about WARM and see how recycling and composting your discards will help our climate.
Stop Trashing the Climate report
Stop Trashing the Climate, co-authored by the Institute for Local Self-Reliance, Eco-Cycle and GAIA, proves a Zero Waste approach is one of the fastest, cheapest and most effective strategies to protect the climate. Significantly decreasing waste disposed in landfills and incinerators will reduce greenhouse gas emissions the equivalent to closing 21% of U.S. coal-fired power plants. This is comparable to leading climate protection proposals such as improving national vehicle fuel efficiency. Indeed, preventing waste and expanding reuse, recycling, and composting are essential to put us on the path to climate stability.
COOL 2012 Campaign
Eco-Cycle partnered with BioCycle and the GrassRoots Recycling Network (GRRN) to launch the Compostable Organics Out of Landfills by 2012 (COOL 2012) campaign to show communities they can achieve significant climate benefits RIGHT NOW by PREVENTING landfill-produced methane.
What can your community do? There are four COOL solutions:
1. Seize the Paper: Commit to recycling a minimum of 75% of all paper and composting the rest by 2012.
2. Source Separate: Require source separation of residential and business waste into three streams: compostables, recyclables and residuals.
3. Feed Local Soils: Support local farmers and sustainable food production with community composting infrastructure.
4. Stop Creating Methane: Public policy needs to first support the elimination of methane by requiring source separation of compostables and recyclables, then mitigate methane from existing sources where organics have already been buried.