The good, the bad and the ugly: how do different greenhouse gases compare?

Which greenhouse gas contributes the most to global warming? The bad news, for those who want a simple answer, is that it really depends on how you define the question. 

One oft-quoted statistic is that three quarters of the world's greenhouse gas emissions are made up of carbon dioxide. Another is that in New Zealand almost half our greenhouse gas emissions come from agriculture. And these emissions aren't carbon dioxide - rather, roughly 2/3 are methane and 1/3 are nitrous oxide. 

But what do these figures mean? Does agriculture produce roughly one out of every two kilograms of gas we emit? Or is agriculture ultimately responsible for roughly half our contribution to global warming? 

Somewhat mysteriously, the answer is – neither. There are three important variables to keep in mind when comparing carbon dioxide, methane and nitrous oxide. The first is the quantity in kilograms of gas emitted - more gas causes more warming. The second is how long gas molecules linger in the atmosphere - and this varies significantly across types of gas. The third is how much energy a kilogram of each type of gas traps in the atmosphere per unit time.

The statistics referred to above don't tell us about the number of kilograms of each gas emitted, nor about the total amount of energy that each type of gas will trap in the atmosphere in the long run. Rather, they are calculated by taking the number of kilograms of each gas that we emit, and multiplying it by a "global warming potential" (GWP). A GWP is the amount of energy that one kilogram of that gas traps in the atmosphere over a 100 year period relative to carbon dioxide. For instance methane's GWP is more than 20, which means that in the 100 years after a kilogram of methane is emitted, it will trap over 20 times as much energy in the earth's atmosphere as one kilogram of carbon dioxide will.

The thing about GWPs is that they only look 100 years into the future. If we care only about the short term, then GWP - or an even shorter term measure - might be the best to use. But if we want to consider the impact of gases more than a hundred years forward, then we might think that GWP over- or understates the effect a gas has on warming. How far ahead should we look? The question remains open for debate.

In this video, Dave Frame from the Victoria University of Wellington Climate Change Institute discusses these differences between the three types of gas. The results might be surprising! Note that Dave’s comparisons are per-kilogram, and don’t necessarily reflect the aggregate contribution to global warming of each gas.

Concerns and capabilities lead to action

The AgDialogue process Motu recently ran was designed to create a dialogue amongst agriculture sectoral groups, government, academics and individual farmers around dealing with New Zealand’s agricultural GHG (greenhouse gas) emissions. One of the outcomes of this discussion was the creation of a matrix to describe how we can get action on wicked problems such as lowering agricultural GHG emissions: who can act and what can they do.

In this short video, Suzi Kerr explains the thinking behind the matrix.
 

Below is the matrix. Rather than being a large computer programme set up to create an alternate reality, the AgDialogue matrix is really a simple way of visualising what Suzi explains in the video.

Basically, an action intended to help reduce our agricultural GHGs can fit into one or more of the boxes in the matrix. The ETS (Emissions Trading Scheme) for example, would fit into the top right box, as a national level regulation designed to incentivise emission reductions. The Agricultural Greenhouse Gas Research Center would fit in the top-middle box.

However, as Suzi points out in the video, we need adequate concern and capabilities as well as regulations to reward good and penalise poor behaviour. By using the AgDialogue matrix, we can identify who could undertake actions, and what these actions could aim to achieve. When we have populated it with a set of existing actions, if there are any gaps, we can come up with creative ways of filling in these gaps – as we did through AgDialogue.

A piece of research, done by Taciano Milfont at Victoria University of Wellington backs up the thinking behind the matrix. Importantly, his research was carried out in New Zealand – something that is very valuable as we often have to rely on research coming from larger countries, and apply their findings here.

Using data from a one year study, Taciano concludes: “Knowing more about global warming and climate change increases overall concern about the risks of these issues, and this increased concern leads to greater perceived efficacy and responsibility to help solving them.”

Taciano’s research paper can be found online for free here.

A special thanks to former Motu Research Analyst Zach Dorner for drafting this post.

Community involvement in environmental education and governance

Environmental education is crucial for engaging people from all walks of life to make informed decisions about issues such as biodiversity loss, climate destabilisation and resource depletion. Ardoin, Clark and Kelsey's recent paper "An exploration of future trends in environmental education research" has explored the possible future directions that environmental education may take. The authors' study was undertaken with an awareness of the increasing impact of global trends such as the technology revolution, the urban age, and the globalisation of environmental issues.

A number of interesting findings flow from the authors' research. One suggestion made is that that environmental education and research may broadening in focus from the individual to community level. The idea that education and research can be inclusive and collaborative is well-instanced in the project around which this blog was founded - the Agricultural Emissions Dialogue process. The project brought together farmers, iwi, economists, scientists, government and other experts to discuss issues around agricultural emissions. Whilst the group conducted no formal research, the dialogues proved to be the catalyst for a number of pieces of research by Motu (see the bottom of this page) and our recently published short film and teaching materials. Two of the earlier entries on this blog have specifically considered the process of dialogue - this post by Ana Ngamoki, and this post by Geoff Simmons.

It may be the case that environmental governance, like environmental education, will increasingly broaden towards a community-focussed approach. The Land and Water Forum's recent series of reports on how freshwater management in New Zealand can be improved called for community decision-making at catchment level, within a framework created by central government. The Forum's third report emphasised the need for community buy-in to ensure regulation is effective, and the importance of giving weight to community-specific needs and values in decision making.

Another issue that Ardoin, Clark and Kelsey touch on is the highlighted opportunity for engagement that social media brings. With that in mind, this is probably a good point at which to remind readers about ways in which they can engage with this blog. Comments are most welcome, as are suggestions for topics (email us at info@motu.org.nz). And to subscribe to receive updates when posts are made, simply enter your email address in the "Follow By Email" field to the right.

Agricultural Emissions Teaching Materials Released

Last month, we released a brand new short film on agricultural emissions. Today, we are pleased to announce the release of a set of free teaching materials to accompany the film. These consist of an editable presentation, complete with speaking notes, and further information on some of the figures that the presentation contains.

Our intention is that a wide range of people – including teachers, lecturers, farmers or people working with farmers – will be able to use the film and presentation to lead a discussion on what we can do about agricultural emissions. Potential audiences include secondary and tertiary students, as well as consumers and farmers. In other words, anyone who eats!

The materials can be downloaded by following the links below. In addition, we have just released the film in physical copy. If you would like to be posted a free DVD which includes the film and materials, please send your name and address to info@motu.org.nz.

We will be happy to support those who wish to use the film and materials by answering specific questions. We'll collate the questions and answers into an FAQ document which will be available soon on the blog and also on the Motu website. If you have any questions at all, please email them through.

The New Zealand Farming Story presentation (.pdf version)
The New Zealand Farming Story presentation (editable Powerpoint)
The New Zealand Farming Story speaking notes
Notes on figures for emissions from meat consumption in presentation

"Origin Green" - certifying the sustainability of Irish primary products

Rural News recently ran this article about a quality assurance scheme initiated by Bord Bai (the Irish Food Board). Called "Origin Green", the scheme guarantees the sustainability of certified foods to consumers. As the article explains, Beef and Lamb New Zealand Chair Mike Petersen thinks that there is scope for New Zealand to do something similar.

The Irish scheme is very similar to an idea developed within New Zealand by the Agricultural Emissions Dialogue and a version of it is already being developed by one of the members, Mike Barton, through his Taupo Beef programme. Mike discusses Taupo Beef in our short film.

More information on Origin Green is available here.

 

Farming within environmental limits

Here is a copy of a brief article by Dr Dan Marsh, which was recently published in the new magazine Primary. It discusses the "Natural Capital" approach to setting limits of runoff from farms (for water quality reasons) as adopted by Horizon regional council.

The idea of farming within environmental limits has attracted a lot of attention in recent months. Some of the debate has been around the allocation and setting of nitrogen leaching limits; limits on the amount of nitrogen that can be allowed to leach from a farm or catchment into rivers or lakes. The recent environment court decision on the Horizon's Proposed One Plan (POP) has put the spotlight on the Natural Capital Approach (NCA) which allocates nitrogen leaching rights at a flat rate per hectare that varies with land use class (LUC).

Motu has done a bit of work looking at an alternative approach of nutrient trading - trading the nutrient emissions that pollute waterways within their catchments under a total cap. This ensures waterways can be protected, while the allowable amount of nutrient run off can happen where it can be most efficiently utilised. Dan Marsh touches on this approach in his article too.

Some of Motu's 2009 work on nutrient trading around Rotorua is summed up nicely in this paper.

Nutrient trading for water quality of course has some interesting parallels with emissions trading for greenhouse gases. A similar Motu working paper on allocating units for the New Zealand ETS (Emissions Trading Scheme - covering greenhouse gases) can be found here, with Suzi Kerr's latest thinking on the contentious issue of allocation and fairness in the ETS is covered in this recent presentation by her.

It's all very interesting and contentious stuff - lots of material to look into! Luckily Dan Marsh's article gives a good summary of some of the issues which we are having to confront as we look seriously at farming within environmental limits.

Thanks to Dan Marsh for providing us with the article for this blog.

The New Zealand Farming Story: Tackling Agricultural Emissions

Today we are very excited to release our new short film on New Zealand’s agricultural emissions. Although the topic may sound dry (though hopefully not too dry if you visit this blog!) our filmmaker Jess Feast has done an excellent job of making an engaging film on an extremely important topic for the future of our country, our planet, our people and our stomachs. (She also made our films about improving the water quality in Lake Rotorua).

The film covers a wide range of topics, and many of the ideas in it come directly from what we learnt through the AgDialogue process. Importantly, we cover how we might be able to achieve some real reductions in New Zealand’s agricultural GHGs (greenhouse gases). You will get to meet some of the participants and experts from AgDialogue, including two of our star farmers, Mike and Megan.

The film speaks for itself, so you are better off watching it than reading about it. But before you do that, I’d just like to acknowledge all the hard work that went into making the film. To all those in the AgDialogue who gave their time and those who have done related research in the past few years, this film is dedicated to you and the hard work you have done.  Also thank you to our filmmaker Jess and the Ministry for Primary Industries for its support. The work will pay off in creating a more sustainable and prosperous future for us and future generations.

Oh, and if you like the film, please share it far and wide. New Zealand is uniquely placed to be able to make a big difference to levels of agricultural GHGs (greenhouse gases) around the world. And everyone in this country can make a difference.

UPDATE: Teaching materials to accompany the film have now also been released. These can be found here.