Why science can burst the Paris Climate Agreement bubble
By Dr Anthony Horton
As I scientist I find myself torn between two realities following Saturday’s historic announcement of the Paris Climate Agreement. The first reality is that the majority of the world’s leaders now accept that climates are changing and that we should and can do something about it. Of course I am very pleased that science has been recognised for the part it will play in this. The second (and more sobering) reality is that science may be the Agreement’s downfall. I am not talking about the lack of a clearly defined roadmap, or KPI’s, against which progress can be measured – which does concern me somewhat as a scientist. Instead, I am talking about something even more scientifically fundamental and concerning in terms of the Agreement.
Two recently published scientific studies have called into question the 2°C target and one of the key tools essential to reaching that target: negative emissions technologies (NETs). Yes you have read correctly, NETs are essential to the target because they basically remove CO2 from the air directly. In the journal ‘Nature Geoscience’, a team led by Reto Knutti from the Institute for Atmospheric and Climate Science in Zurich Switzerland together with colleagues from the International Institute for Applied Systems Analysis argues that the 2°C target is essentially a policy or political target rather than a scientific one. This is based on the lack of scientific assessment that 2°C is a safe level of warming.
With respect to NETs, research led by Pete Smith from the Institute of Biological and Environmental Sciences at the University of Aberdeen contends that large-scale deployment of these technologies are essential to realise a greater than 50% chance of limiting warming to 2°C, although there are a number of important factors that require very careful consideration.
Knutti’s research team investigated the scientific issues presented by a temperature-based target and proposed alternative targets addressing the concentration of greenhouse gases (GHGs), global energy uptake and global sea levels. Global surface temperature meets most of the requirements for a climate target according to Knutti’s team; however, the baseline (e.g. pre industrial conditions) is poorly defined. In IPCC assessments, pre industrial denotes 1750. An instrumental record of global temperatures does not exist prior to 1850 and CO2 concentrations from that time are not well characterised. From a scientific perspective, 1850-1900 would be defendable but as different time periods influence how historical emissions are accounted for in a country’s total, this could cause lengthy debate.
The researchers also reported large-scale surface warming patterns appear to scale linearly with global mean surface temperature changes, and that relative changes in precipitation also scale linearly with temperature. However, the number of events exceeding a threshold increases non-linearly. In a 1°C warmer world, the number of very hot days exceeding a percentile based threshold increases approximately 6 fold globally, and more than 20 fold for a 2°C warmer world. In terms of adaptation, the impact risk of a 4°C warmer world is much greater than for a 2°C warmer world – although the potential to reduce that risk at 4°C is not much higher than at 2°C.
There are seven classes of NETs: bioenergy with carbon capture and storage; direct air capture from ambient air by engineered chemical reactions; enhanced weathering of minerals; afforestation and reforestation; the manipulation of carbon uptake by the ocean biologically or chemically; changing agricultural practices; and lastly, converting biomass to biochar for use as a soil amendment. Each of these methods vary significantly in terms of land use requirements, GHG emissions emitted/removed, water & nutrient use, energy produced/required, impacts on surface albedo, and cost.
According to Smith and his team, further research is needed to inform society of the potential risks and opportunities that NETs present. Common modelling frameworks are required in order to implement learning, cost and efficiency curves for all of the NETs. Curves for each NET will enable future models to compile trajectories of NET development, which will in turn facilitate the selection of lowest cost options. Socioeconomic governance systems are also required for all NETs to incentivise further research, development and the implementation of infrastructure in the most sustainable manner.
In concluding their article, the authors stated a number of factors that highlight how carefully NETs need to be considered prior to implementation. In addition to resource usage implications, relying on NETs in future is very risky if used as a means to facilitate continued usage of fossil fuels. Also, any failure of NETs to deliver the expected mitigation as a result of its limitations leaves no ‘plan B’. Perhaps of most concern is the authors’ statement that there is no NET or combination of NETs that can meet the 2°C target without significant impacting land, energy, water, nutrients, albedo and cost.
See the article in Nature Climate Change here.
About the author: Anthony Horton holds a PhD in Environmental Science, a Bachelor of Environmental Science with Honours and a Diploma of Carbon Management. He has a track record of delivering customised solutions in Academia, Government, the Mining Industry and Consulting based on the latest wisdom and his scientific background and experience in Climate/Atmospheric Science and Air Quality. Anthony’s work has been published in internationally recognised scientific journals and presented at international and national conferences, and he is currently on the Editorial Board of the Journal Nature Environment and Pollution Technology. Anthony also blogs on his own site, The Climate Change Guy.
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I am glad you noticed. As Bill McKibben says…. “We’ll be blocking pipelines, fighting new coal mines, urging divestment from fossil fuels — trying, in short, to keep weakening the mighty industry that still stands in the way of real progress.”
Civil disobedience is the only option.
Our ‘leaders’ have really stuffed up…..
If you have been following advances in integrated circuit technology, or just following technology, it is to late for Civil disobedience, well you can try, but it wont be effective, and any way it’s terrorism, but i suppose you could try, if my hands were tied and a gun pointed at my head, i would not just kneel there waiting. And our leaders are us, or why are fools, leaders.
musicinhills It is not terrorism and I do not no what integrated circuit technology has to do with it. What do you mean ?
Meanwhile another fat headed baby boomer …Climate Denier Karl Rove: Who Cares What Happens to Our Grandchildren? We’ll be Dead. http://climatecrocks.com/2015/12/13/climate-denier-karl-rove-who-cares-what-happens-to-our-grandchildren-well-be-dead/
‘Fossil Fuels’ Nowhere to be Found in the Paris Agreement
Wow COP21 removes the right for poor countries to sue for damages from climate change.
For vulnerable island nations, The internationally agreed upon rise of 2 degrees would essentially render their countries uninhabitable. So, much of the discussions in Paris have been about forcing concessions from these desperate countries. As Naomi Klein says in this video dispatch, “I don’t think I’ve ever seen a situation where countries are being negotiated to accept the terms of their own annihilation.”
Our current fossil fools who want to keep mining coal ; They will go down in history ( if a literate society survives to do history) as the men who killed Australia ( and a lot of other nations).
it is so sad that we who got so rich on coal and evermore greedily maintain our wealth with overuse of gas and oil are so negligent in developing the energy source for the billions in Asia and Africa to get rich. We were leading in tech research before the science cuts at the end of last century and the rabbott punch proved the coup de gras.
There is a battle to come because India and China have huge upwardly mobile populations and markets for oil and if they decide to fight for their share??????