For most of us, it’s safe to say that once our trash leaves the curb for the garbage dump, it’s mostly a mystery about what happens next. Not surprisingly, the serious environmental shortcomings of solid waste are also poorly understood, despite the fact that it’s one of the chief contributors to climate change.
Worldwide, greenhouse gas emissions from landfills top the charts. They’re the third highest producer of methane (CH4), overshadowed only by the livestock and energy sectors. Methane is 25 times more potent than carbon dioxide (CO2) at trapping heat in our atmosphere. If methane emissions were mitigated, significant and more rapid reductions in Earth’s warming would return greater short-term dividends than CO2.
Problems with Mitigating Waste Emissions
How we process our waste affects whether it harms the environment. In other words, not all landfills are created equal. Successful systems for capturing methane at dumpsites have been employed in the United States for many years. In developing countries, waste management practices are more problematic. And even the most buttoned-up systems can spring a leak of heat-trapping methane gas.
In 2022, RMI (formerly known as Rocky Mountain Institute) and partners published a comprehensive report about municipal solid waste. In it, they tic off the many factors that complicate the consequences of trash:
- Volume and type of organic waste
- Moisture content
- Gas capture effectiveness
- Land cover type
- Monitoring and quantification practices
- … to name a few
In short, solid waste is a complex problem without standardized solutions. Waste management practices are a hodgepodge depending on where you live in the world. Open dump sites are common in developing countries. And, regulatory standards vary from place to place. Still, the RMI report saw the “significant untapped potential” for successfully limiting emissions. “Now is the time to act,” its authors wrote.
How to Reduce Methane from Waste
Let’s get back to you and me. There are ways to reduce waste emissions — curbing the creation of trash is a good start. Consuming less of everything, which includes goods from packaged food to fast fashion, decreases volume. For businesses committed to sustainability, consumption means reductions, too, as well as adopting the mantras of reuse/recycle, upcycling, and lifecycling. Let’s add a few more: conversion/composting, transformation/waste-to-energy. The last resort for any byproduct should be the landfill.
Although these strategies are taking root, they’re typically out of reach in developing economies. For many places, the biggest opportunities (and challenges) will be rehabilitating dumps and adding gas capture systems. Cost, lack of regulatory structure, and cultural differences will make these changes harder to come by.
Another tool in the toolbox is monitoring. We can’t fix what we can’t see. And in the case of methane — a colorless, odorless gas — pinpointing where and how much methane is being emitted is crucial. It requires a commitment to monitoring or overseeing emissions, usually by a secondary partner, agency or watchdog. New technologies are helping, such as satellite arrays for global GHG monitoring. Several are in the works. Those coincide with new policy initiatives that are globalizing this not-in-my-backyard problem.
Policy Initiatives Around Methane Reduction
More eyes are on methane than at any other point in our recent environmental history. The evidence:
- The Global Methane Pledge, launched at COP26, commits countries to reduce methane emissions by 30 percent by 2030. As of COP27, 150 countries have signed.
- A new Methane Alert and Response System (MARS) will use satellite observations to alert governments and operators about large emissions.
- The U.S. State Department has launched the Global Waste Pathway to focus on solid waste exclusively.
- The Clean Air Task Force and RMI are working with Global Methane Hub funding on a new effort to track and manage methane emissions from waste sites in Africa and Latin America.
- The White House held its first “methane summit” in July 2023 and launched a task force dedicated to emissions.
- Climate TRACE has made available a facility-level global inventory of GHG emissions of more than 70,000 sources.
To top it off, there’s also the work of activists who are taking emissions monitoring into their own hands. Perhaps the next time you take out the trash, the black box of where it’s going may not be so dim.