Why Methane Should Be Treated Differently Compared To Long-lived Greenhouse Gases

Why Methane Should Be Treated Differently Compared To Long-lived Greenhouse Gases Livestock is a significant source of methane, a potent but short-lived greenhouse gas. from www.shutterstock.com, CC BY-SA

New research provides a way out of a longstanding quandary in climate policy: how best to account for the warming effects of greenhouse gases that have different atmospheric lifetimes.

Carbon dioxide is a long-lived greenhouse gas, whereas methane is comparatively short-lived. Long-lived “stock pollutants” remain in the atmosphere for centuries, increasing in concentration as long as their emissions continue and causing more and more warming. Short-lived “flow pollutants” disappear much more rapidly. As long as their emissions remain constant, their concentration and warming effect remain roughly constant as well.

Our research demonstrates a better way to reflect how different greenhouse gases affect global temperatures over time.

Cost of pollution

The difference between stock and flow pollutants is shown in the figure below. Flow pollutant emissions, for example of methane, do not persist. Emissions in period one, and the same emissions in period two, lead to a constant (or roughly constant) amount of the pollutant in the atmosphere (or river, lake, or sea).

With stock pollutants, such as carbon dioxide, concentrations of the pollutant accumulate as emissions continue.

Why Methane Should Be Treated Differently Compared To Long-lived Greenhouse Gases Flow and stock pollutants over time. In the first period, one unit of each pollutant is emitted, leading to one unit of concentration. After each period, the flow pollutant decays, while the stock pollutant remains in the environment. provided by author, CC BY

The economic theory of pollution suggests different approaches to greenhouse gases with long or short lifetimes in the atmosphere. The social cost (the cost society ought to pay) of flow pollution is constant over time, because the next unit of pollution is just replacing the last, recently decayed unit. This justifies a constant price on flow pollutants.

In the case of stock pollutants, the social cost increases with constant emissions as concentrations of the pollutant rise, and as damages rise, too. This justifies a rising price on stock pollutants.


Read more: Cows exude lots of methane, but taxing beef won't cut emissions


A brief history of greenhouse gas “equivalence”

In climate policy, we routinely encounter the idea of “CO₂-equivalence” between different sorts of gases, and many people treat it as accepted and unproblematic. Yet researchers have debated for decades about the adequacy of this approach. To summarise a long train of scientific papers and opinion pieces, there is no perfect or universal way to compare the effects of greenhouse gases with very different lifetimes.

This point was made in the first major climate report produced by the Intergovernmental Panel on Climate Change (IPCC) way back in 1990. Those early discussions were loaded with caveats: global warming potentials (GWP), which underpin the traditional practice of CO₂-equivalence, were introduced as “a simple approach … to illustrate the difficulties inherent in the concept”.

The problem with developing a concept is that people might use it. Worse, they might use it and ignore all the caveats that attended its development. This is, more or less, what happened with GWPs as used to create CO₂-equivalence.

The science caveats were there, and suggestions for alternatives or improvements have continued to appear in the literature. But policymakers needed something (or thought they did), and the international climate negotiations community grasped the first option that became available, although this has not been without challenges from some countries.

Better ways to compare stocks and flows

An explanation of the scientific issues, and how we address them, is contained in this article by Michelle Cain. The approach in our new paper shows that modifying the use of GWP to better account for the differences between short- and long-lived gases can better link emissions to warming.

Under current policies, stock and flow pollutants are treated as being equivalent and therefore interchangeable. This is a mistake, because if people make trade-offs between emissions reductions such that they allow stock pollutants to grow while reducing flow pollutants, they will ultimately leave a warmer world behind in the long term. Instead, we should develop policies that address methane and other flow pollutants in line with their effects.

Then the true impact of an emission on warming can be easily assessed. For countries with high methane emissions, for example from agriculture, this can make a huge difference to how their emissions are judged.

For a lot of countries, this issue is of secondary importance. But for some countries, particularly poor ones, it matters a lot. Countries with a relatively high share of methane in their emissions portfolios tend to be either middle-income countries with large agriculture sectors and high levels of renewables in their electricity mix (such as much of Latin America), or less developed countries where agricultural emissions dominate because their energy sector is small.

This is why we think the new research has some promise. We think we have a better way to conceive of multi-gas climate targets. This chimes with new possibilities in climate policy, because under the Paris Agreement countries are free to innovate in how they approach climate policy.

Improving the environmental integrity of climate policy

This could take several forms. For some countries, it may be that the new approach provides a better way of comparing different gases within a single-basket approach to greenhouse gases, as in an emissions trading scheme or taxation system. For others, it could be used to set separate but coherent emissions targets for long- and short-lived gases within a two-basket approach to climate policy. Either way, the new approach means countries can signal the centrality of carbon dioxide reductions in their policy mix, while limiting the warming effect of shorter-lived gases.

The new way of using global warming potentials demonstrably outperforms the traditional method in a range of emission scenarios, providing a much more accurate indication of how stock and flow pollutants affect global temperatures. This is especially so under climate mitigation scenarios.

Well designed policies would assist sectoral fairness within countries, too. Policies that reflect the different roles of stock and flow pollutants would give farmers and rice growers a more reasonable way to control their emissions and reduce their impact on the environment, while still acknowledging the primacy of carbon dioxide emissions in the climate change problem.

An ideal approach would be a policy that aimed for zero emissions of stock pollutants such as carbon dioxide and low but stable (or gently declining) emissions of flow pollutants such as methane. Achieving both goals would mean that a farm, or potentially a country, can do a better, clearer job of stopping its contribution to warming.The Conversation

About The Author

Dave Frame, Professor of Climate Change, Victoria University of Wellington; Adrian Henry Macey, Senior Associate, Institute for Governance and Policy Studies; Adjunct Professor, New Zealand Climate Change Research Institute. , Victoria University of Wellington, and Myles Allen, Professor of Geosystem Science, Leader of ECI Climate Research Programme, University of Oxford

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Related Books

Drawdown: The Most Comprehensive Plan Ever Proposed to Reverse Global Warming

by Paul Hawken and Tom Steyer
9780143130444In the face of widespread fear and apathy, an international coalition of researchers, professionals, and scientists have come together to offer a set of realistic and bold solutions to climate change. One hundred techniques and practices are described here—some are well known; some you may have never heard of. They range from clean energy to educating girls in lower-income countries to land use practices that pull carbon out of the air. The solutions exist, are economically viable, and communities throughout the world are currently enacting them with skill and determination. Available On Amazon

Designing Climate Solutions: A Policy Guide for Low-Carbon Energy

by Hal Harvey, Robbie Orvis, Jeffrey Rissman
1610919564With the effects of climate change already upon us, the need to cut global greenhouse gas emissions is nothing less than urgent. It’s a daunting challenge, but the technologies and strategies to meet it exist today. A small set of energy policies, designed and implemented well, can put us on the path to a low carbon future. Energy systems are large and complex, so energy policy must be focused and cost-effective. One-size-fits-all approaches simply won’t get the job done. Policymakers need a clear, comprehensive resource that outlines the energy policies that will have the biggest impact on our climate future, and describes how to design these policies well. Available On Amazon

This Changes Everything: Capitalism vs. The Climate

by Naomi Klein
1451697392In This Changes Everything Naomi Klein argues that climate change isn’t just another issue to be neatly filed between taxes and health care. It’s an alarm that calls us to fix an economic system that is already failing us in many ways. Klein meticulously builds the case for how massively reducing our greenhouse emissions is our best chance to simultaneously reduce gaping inequalities, re-imagine our broken democracies, and rebuild our gutted local economies. She exposes the ideological desperation of the climate-change deniers, the messianic delusions of the would-be geoengineers, and the tragic defeatism of too many mainstream green initiatives. And she demonstrates precisely why the market has not—and cannot—fix the climate crisis but will instead make things worse, with ever more extreme and ecologically damaging extraction methods, accompanied by rampant disaster capitalism. Available On Amazon

From The Publisher:
Purchases on Amazon go to defray the cost of bringing you InnerSelf.comelf.com, MightyNatural.com, and ClimateImpactNews.com at no cost and without advertisers that track your browsing habits. Even if you click on a link but don't buy these selected products, anything else you buy in that same visit on Amazon pays us a small commission. There is no additional cost to you, so please contribute to the effort. You can also use this link to use to Amazon at any time so you can help support our efforts.

 

enafarzh-CNzh-TWnltlfrdehiiditjakomsfaptruesswsvthtrurvi

LATEST VIDEOS

What Is The Future Of Climate Change?
by Simon Donner
You would think with all the chatter going on about climate that we’d all have a good understanding on the elements of…
Why Marianne Williamson's Candidacy for President Is Important
Why Marianne Williamson's Candidacy for President Is Important
How do you know something exists if you never hear about it? How do you know about the truth, which is often "the other…
Would You Eat Meat Grown From Cells In A Laboratory? Here's How It Works
Would You Eat Meat Grown From Cells In A Laboratory? Here's How It Works
by Leigh Ackland
For many of us, eating a meal containing meat is a normal part of daily life. But if we dig deeper, some sobering…
Climate System “Getting Unhinged” as Massive Heat Wave Causes Record Melting of Greenland Ice Sheet
by Democracy Now!
The massive heat dome that shattered all-time temperature records across much of Europe last week has settled in over…
Why We're Heading For A Climate Catastrophe
by BBC Newsnight
Scientists say the world is completely off track.
A Climate Reckoning In The Heartland
by CBS News
"A historic flood in March 2019 left much of America's heartland under water. Partiularly hard-hit were Midwestern…
What Would Happen If Antarctica Melted?
by Put Put 1
"What Would Happen If Antarctica Melted?
Dr. Peter Wadhams: Arctic Research & the Methane Risk
by UPFSI
Peter Wadhams is back on ScientistsWarning.TV with a comprehensive analysis of the reticent approach that part of the…

LATEST ARTICLES

What Is The Future Of Climate Change?
by Simon Donner
You would think with all the chatter going on about climate that we’d all have a good understanding on the elements of…
People Of Color Don’t Get Credit For Climate Concern
People Of Color Don’t Get Credit For Climate Concern
by U. Oregon
While their contributions to the climate change movement remain largely unrecognized, people of color are just as…
New Research Shows That Antarctica's Largest Floating Ice Shelf Is Highly Sensitive To Warming Of The Ocean
New Research Shows That Antarctica's Largest Floating Ice Shelf Is Highly Sensitive To Warming Of The Ocean
by Dan Lowry
Scientists have long been concerned about the potential collapse of the West Antarctic Ice Sheet and its contribution…
It'll Be Hard, But We Can Feed The World With Plant Protein
It'll Be Hard, But We Can Feed The World With Plant Protein
by Richard Trethowan
A UN report released last week found a quarter of the world’s carbon emissions come from the food chain, particularly…
Underground Water Sources For Billions Could Take More Than A Century To Respond Fully To Climate Change
Underground Water Sources For Billions Could Take More Than A Century To Respond Fully To Climate Change
by Mark O. Cuthbert, et al
Groundwater is the biggest store of accessible freshwater in the world, providing billions of people with water for…
Why Is The Australian Energy Regulator Suing Wind Farms?
Why Is The Australian Energy Regulator Suing Wind Farms?
by Samantha Hepburn
The Australian Energy Regulator (AER) is suing four of the wind farms involved in the 2016 South Australian blackout -…
Groundwater Reserves In Africa May Be More Resilient To Climate Change Than First Thought
Groundwater Reserves In Africa May Be More Resilient To Climate Change Than First Thought
by Mark O. Cuthbert and Richard Taylor
Groundwater reserves in Africa are estimated to be 20 times larger than the water stored in lakes and reservoirs above…
Australia Urgently Needs Real Sustainable Agriculture Policy
Australia Urgently Needs Real Sustainable Agriculture Policy
by InnerSelf Staff
Australia has made a global commitment to “sustainable agriculture”, an endeavour seen as increasingly crucial to…