World must act now to cut methane emissions say the co-authors of UNEP-CCAC report

by CCAC Secretariat - 5 November, 2022

A UNEP/CCAC report calls for an era of accelerated methane mitigation as emissions keep increasing. The Global Methane Assessment 2030 Baseline report. Why act now: a new era for accelerated implementation examines baseline (business-as-usual) projections of methane emissions over the coming decade, their relationship to the Global Methane Pledge and why we need to act now to accelerate implementation. 

Last year the climate and Clean Air Coalition and UN Environment Program published the landmark Global Methane Assessment, which has led in part to the launch of the Global Methane Pledge at COP 26 in Glasgow. There is now a growing global political consensus that action on methane is a critical component of mitigating all climate forcers. Methane mitigation will help us hold to our commitment to achieve a 1.5 consistent pathway through this century which achieves both our climate objectives and our development objectives.

Nathan Borgford-Parnell, Science Affairs Coordinator with the Climate and Clean Air Coalition, speaks with four of the co-authors of the report to discuss the growth rates of methane, satellite measurements and concrete measures to mitigate methane emissions in all three main sectors: fossil fuels, waste and agriculture. They underline how essential it is to integrate socio-economic considerations in the design of mitigation policies to avoid aggravating existing inequalities. 


  • Ilse Aben, Senior Scientist, the Netherlands Institute for Space Research (SRON), CCAC Scientific Advisory Panel Member 
  • Drew Shindell, Nicholas Professor of Earth Science, Duke University, CCAC Scientific Advisory Panel Member 
  • Lena Höglund-Isaksson, Senior Research Scholar, International Institute for Applied Systems Analysis, CCAC Scientific Advisory Panel Member 
  • Benjamin Poulter, Research Scientist, NASA Goddard Space Flight Center 

Nathan Borgford-Parnell: In 2021 the Global Methane Assessment showed that significant action is needed, particularly in this decade, to reduce methane along with all other climate forcers if we're going to achieve our 1.5 target. It also showed that this is achievable. These messages really sparked something in the world as evidenced by the launch of the Global Methane Pledge at COP26 in Glasgow. 

We’re now a year out from Glasgow and we're coming out with this new report. The Global Methane Assessment 2030 Baseline Report. Drew, starting with you. What does this 2030 Baseline Report add to the global methane assessment story and how is it going to carry us forward to this decade? 

Drew Shindell: The Baseline Report is a very detailed study of where our current policies are taking us. So, this isn't pledges where countries have said we're going to aim for net zero or we're going to do something in particular like the Global Methane Pledge, right. This looks at what we actually have in place in our existing laws and regulations. And so, the message, unfortunately, is that our current trajectory is continued, very rapid growth in methane emissions, and therefore the concentrations in the atmosphere. 

I think what that's really setting out for us is that we knew all along the Global Methane Pledge would be a challenge, but it's actually even more of a challenge than we thought since we're continuing to go dramatically in the wrong direction. The bottom line of this is really a call for rapidly accelerating implementation of the kind of policies that we outlined in the in the original global methane assessment. 

Nathan Borgford-Parnell: Lena and Ben, a lot of information has come out in the in the last couple of weeks about the rate of methane emissions into the atmosphere. It seems the rate is continuing to be extremely high and increasing. And I wonder if you can put the some of the main conclusions of this report into context of these latest numbers? 

Lena Höglund-Isaksson: So yeah, so this is of course extremely worrying that we see these continued increases. It might mean that the baseline assumptions that we have in the report will be exceeded. But it makes it even more urgent then that we really have to address these emissions in particular to mitigate the warming in the next two decades. 

Benjamin Poulter: The growth of methane in the atmosphere in 2020 has doubled over the previous decade of growth rates and then that doubling in 2020 has been sustained for 2021. And it looks like we will also be seeing sustained increase of these extraordinarily high rates for 2022. So about 18 parts per billion for the past two years and now for 2022. 

We are in a new era of extraordinarily high growth rates of methane and new space-based observations coming from both the private sector and the public space agencies feeding into programs like the International Methane Emissions Observatory will help us better understand what is happening and to be able to better manage and mitigate emissions. 

Nathan Borgford-Parnell: That really highlights we need to start identifying, as quickly as possible, all of the sources of methane and getting a handle on them. Ilse, turning to you. Can you talk about how well we understand where these methane emissions are coming from, what the uncertainties are and where we can achieve real mitigation now? 

Ilse Aben: We get our knowledge on methane from a number of sources. First the so-called bottom-up emission inventories, where you use activity data and emission factors to come up with total emissions numbers for a sector and for a country. But what is also important, of course, is that we use actual measurements, which is what we call top-down, using atmospheric measurements to learn something about where the main sources of methane are. 

So, what we do know, with a high degree of accuracy based on atmospheric measurements, is how much total methane is increasing in the atmosphere. What becomes more uncertain is understanding where specifically the increases are coming from. To help us understand what extent the bottom-up reported emissions are correct or incorrect, we have been doing atmospheric measurements for a number of decades. This includes aircraft observations with aircrafts, and also even with remote sensing from the Earth service. And lately we have been adding satellite observations to this whole package of atmospheric observation from which we can learn. 

Unfortunately, atmospheric measurements don’t tell you, this methane is coming from a coal mine and this one is coming from a flaring installation for example. It does not work like that. But what we have been seeing with satellites for the first time on the global scale are these so-called super emitters of methane, which are very localized point sources of methane. 

If we look really on the short term, the satellite observations of super emitters give opportunities to reduce and large amounts of methane. So that is part of where the attention should be going to, but not only, of course. 

Nathan Borgford-Parnell: Another element of the Baseline report was looking at the Global Methane Pledge target, which was launched last year at COP-26. The pledge itself is a commitment by countries to support mitigation of methane to achieve emissions that are at least 30% below 2020 levels by 2030. Can you talk more about what we can do now based on existing data and information to achieve this target? 

Lena Höglund-Isaksson: To keep warming within the limits in the next two decades, we really have to address all of the sources of methane, this includes the fossil fuel industry, so oil, coal and gas, then its agriculture and finally waste and wastewater sources. If we look at the fossil fuel industry this is the sector where we can achieve large reductions, from 75% or even more, relatively easily and at relatively low cost. But to do this we probably need more regulatory frameworks in place. In order to force these investments, because right now we have to understand that these investments are not happening, even if they are cost effective. 

When it comes to the waste and wastewater sector, we need to increase or to improve the infrastructure that we have, in particular in developing countries which would require quite a lot of public funding. But at the same time, when you do it, it is likely to come with a lot of health benefits also for the population. So, for society as a whole, it is probably a very beneficial thing to do. 

The last sector and very important sector is agriculture and there we have three quarters of these emissions come from dairy and non-dairy cattle. And this is the sector that is very difficult to reduce emissions through different types of technical solutions. So, to achieve significant reductions in this sector, we have to find ways to also cut the animal stocks. 

Benjamin Poulter: The Baseline Report highlights the contrast between the need for decarbonization and the temperature response to decarbonizing the economy with mitigating methane emissions.  

The baseline report gives us a sense of what we can do to, to bend that curve, to keep us below the 1.5 or 2 degrees warming by mitigating methane in the short term. It shows us why fulfilling commitments like the global methane pledge is important because we are already seeing the impacts of climate change on ecosystems food security. 

And we are starting to potentially see feedbacks from the impacts that climate change is having on wetland ecosystems that produce methane naturally. 

Nathan Borgford-Parnell: Finally, for all of you, what would be the one key main message out of this report, particularly for the global methane pledge community that you would like to see communicated to COP27? 

Lena Höglund-Isaksson: We make sure that this pledge delivers. And I think this report gives us here much more information about where and in what sectors and regions we should be looking to find the solutions for reducing the emissions. We have enough information to act and it’s really urgent that we act, so we cannot sit and wait for the perfect measurements so that we really have to proceed with mitigation. 

Benjamin Poulter: I hope to see at COP27 this continued education about the growth of methane and its contribution to warming. There's been remarkable coordination between the private sector and the public space sector in developing and observing constellation of spacecraft that can help us deal with this problem. 

Ilse Aben: We have no time to waste. If you look at the report, because we are not achieving decrease, we're there's an increase in methane animations. If we continue this path. But on the other hand there is hope because we have all these opportunities. 

And that's what we should now focus our attention to and to really start with action. That would be my, my hope and my advice. 

Drew Shindell: Well, I think Ilse put that beautifully. There's no time to waste. This Baseline report shows that our best estimate is an increase of somewhere in the range of 10 to 15% over the decade. But you know, the past two years have seen record growth in methane emissions. And it's too soon to determine how much of that is anthropogenic and how much is natural. But the pace of the last two years has already got us about halfway to what we projected over the entire decade. 

So, the time to act is, you know now, if not yesterday. And we really need to accelerate implementation. 

Nathan Borgford-Parnell: Thank you very much for those messages. It’s something that I hope the negotiators at COP take to heart. Because this really is the opportunity of the decade. And there is a lot of potential within the Climate and Clean Air Coalition to help us with our policy recommendations and advocacy with countries. Methane is now on everybody's radar. Thank you for your time for this conversation. 

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