While day one largely focused on the impacts of a 1.5C warmer world and how to adapt to them, day two turned towards meeting the 1.5C goal set out in the Paris Agreement, and the implications for emissions reductions, financing, and governance.
Before we summarise the day, Carbon Brief interviewed a range of attendees on the feasibility of the 1.5C limit. The video features, in order of appearance:
- Prof Michael Oppenheimer – professor of geosciences and international affairs, Princeton University
- Dr Stephen Cornelius – chief advisor on climate change, WWF-UK
- Prof Saiful Islam – professor of hydrology and climate change, Bangladesh University
- Achim Steiner – director of the Oxford Martin School, University of Oxford
- Simon Bullock – senior campaigner at Friends of the Earth
- Prof Myles Allen – professor of geosystem science at the Environmental Change Institute, University of Oxford
- Dr Emily Shuckburgh – head of open oceans, British Antarctic Survey
- Prof Piers Forster – director of the Priestley International Centre for Climate, University of Leeds
Part 2 features, in order of appearance:
- Prof Pete Smith, chair in plant & soil science at the Institute of Biological and Environmental Sciences, University of Aberdeen
- Prof Kevin Anderson, deputy Director of the Tyndall Centre for Climate Change Research
- Dr Valérie Masson-Delmotte, senior scientist at the Laboratoire des Sciences du Climat et de l’Environnement and co-chair of IPCC Working Group I
- Dr Joeri Rogelj, research scholar at the International Institute for Applied Systems Analysis (IIASA)
Pathways to 1.5C
The day began with Janos Pasztor, senior advisor to the UN secretary-general, opened the day’s talks by sharing his thoughts on the mitigation challenges of 1.5C:
“We can [now] actually concentrate on the real implementation of the Paris Agreement, which is about what countries will actually do to reduce emissions, to adapt to climate change, to provide financial resources.”
Pasztor highlighted that achieving stringent mitigation is going to require a fundamental change for society:
“In the longer-term, I think it’s very clear that in order to reach those goals and maintain those goals, we need nothing less than a revolution, not just in terms of new technologies, but also social organisation – the way we make use of those technologies.”
Picking up on a theme that has been prominent during the conference, Pasztor said that these technologies could include negative emissions. But he’s still not sure if they are a “really serious set of technologies” that will start making a difference, or a “simple fudge factor to make sure our global models come to zero [emissions]”.
Summarising some of the discussions from day one of the conference, Pasztor put a question to the delegates sitting before him:
“There are mixed messages coming out here. Can we, or can we not, reach 1.5C? Or even 2C? And to what extent is 1.5C going to be more difficult?”
This challenge led nicely into the talk from Dr Elmar Kriegler, vice-chair of sustainable solutions at the Potsdam Institute for Climate Impact Research, who presented on the latest scientific literature regarding the emissions reductions needed to keep global temperature rise to 1.5C above pre-industrial levels.
The first step to reducing emissions down to zero is to reverse the trend of increasing emissions, noted Kriegler. Once emissions peak, he asked whether we can then reduce emissions fast enough to meet the 1.5C limit.
Underlying all the emissions pathways for 1.5C is the need to shift investment from fossil fuels to renewable energy, Kriegler noted, and the factor that “really can’t be emphasised enough” is phasing out coal.
Kriegler went on to discuss what a carbon-neutral society could look like and some of the remaining research challenges. One of the most prominent is how to tackle the hard-to-eliminate emissions – or “decarbonisation bottlenecks” – in sectors, such as freight, aviation, shipping, heavy industry and agriculture.
The emissions pathways for 1.5C that have emerged from the latest research will “hopefully” be ready to run through global climate models to feed into the IPCC’s Sixth Assessment Report (AR6), said Kriegler, but won’t be in time for the IPCC’s 1.5C special report.
Mid-morning, the conference turned to finance. Jane Ambachtsheer, partner and global head of responsible investment at Mercer Investments, explained how an increasing number of investors are taking account of climate risks.
After an informative run through of the the role of the private sector in financing 1.5C by Peter Wheeler, executive vice president of The Nature Conservancy, Prof Saleemul Huq, a senior fellow at the International Centre for Climate Change & Development, joined a panel discussion covering, among other topics, the critical need for capital flows from the global north to south.
Development, technology and governance
After a short break for coffee, Huq continued the discussion about the societal and developmental implications of the Paris Agreement, highlighting how the difference in terms of climate impacts between holding warming at 1.5C versus 2C will fall disproportionately hard on the 100 most vulnerable countries, despite being responsible for just 5% of global emissions.
As well as addressing the challenge of adaptation and the question of loss and damage, we need a conversation about who pays for access to cleaner energy in developing countries, said Prof Harald Winkler, director of the Energy Research Centre at the University of Cape Town.
Ending on a somewhat more controversial note, Huq responded to a question about whether attribution science could be a useful line of research for loss and damage by saying it was “key to unlocking new ways” of compensating nations already experiencing climate change impacts.
Turning to technology options, Professor Stuart Haszeldine, an expert in carbon capture and storage at the University of Edinburgh, described the process of carbon capture and storage and its potential for bringing down emissions. He argued that there is no technical reason to delay rolling out CCS and that it can work profitably, but there has been no clear ask from governments to develop the industry.
Dr Bronson Griscom, director of forest carbon research at The Nature Conservancy, then talked through some of the “natural” methods of taking up CO2 from the atmosphere, such as reforestation, biochar, peat restoration and grazing management. Carbon Brief looked at some of these negative emissions options in our recent series.
The afternoon sessions gave delegates three choices: mitigation pathways for 1.5C, financing 1.5C and the societal and development implications of the Paris Agreement.
The session on mitigation pathways began with a summary of the legal implications of the Paris Agreement. MJ Mace, a senior research fellow at SOAS University of London, argued the key job for academics is to provide narratives for how we can stay below 1.5C, without overshooting. What needs to be done can be done with the technology we have today, with no need for negative emissions or grand technological interventions, Mace argued.
This was contrasted in the next talk by Dr Oliver Geden, head of the EU division at the German Institute for International and Security Affairs, who suggested pursuing a 1.5C limit invites inconsistency and is “not particularly actionable”. Geden argued the political focus should, instead, be on the more actionable target of achieving net zero emissions and that the inevitable overshoot could be mInimised by setting boundaries on the maximum size and latest end date.
Prof Pierre Friedlingstein, chair of mathematical modelling of climate systems at the University of Exeter, suggested the estimate that there are five years worth of current emissions left before we exceed the carbon budget to stay under 1.5C is too pessimistic. Accounting for the fact that the cumulative warming per unit of carbon dioxide observed recently is lower than in the majority of climate models extends the 1.5C budget timeline to 20-30 years.
On an optimistic note, Dr Neil Edwards from the Open University presented some new integrated assessment modelling results outlining a plausible policy pathway to have a 50% probability of staying below 1.5C. The scenario involves only limited use of negative emissions, requires a carbon tax and must begin immediately, but, ultimately, would produce a financial saving not a cost, said Edwards. He also emphasised how “the dynamics of choice” and society as a whole will be paramount.
The finance session attempted to grapple with how best to pay for the global-scale changes demanded by the 1.5C limit. It was chaired by Prof Cameron Hepburn, director of the economics of sustainability programme at the Institute for New Economic Thinking at the Oxford Martin School. Many topics were raised by the presenters, such as tackling fossil fuel subsidies, mobilising private finance and leaping legal hurdles.
Jessica Williams, an environmental and climate risk analyst at S&P Global, focused on financing the energy storage required to complement renewable power generation.
Noémie Klein, a consultant at Ecofys, adapted her planned presentation after noting that the topic of carbon pricing had largely been absent from the conference. She showed where around the world carbon pricing was already being implemented.
The session on development discussed the challenges of meeting the long-term goals set out in the Paris Agreement while also tackling the wider issue of equity.
Prof Jean-Pascal van Ypersele, professor of climatology and environmental sciences at the Universite catholique de Louvain in Belgium and former vice-chair of the IPCC, gave a quick tour of the history of the IPCC long-term temperature goal. There weren’t many mentions of 1.5C, though it did feature on his “I ♡ 1.5C” tie.
The final session first saw Prof Myles Allen, who leads the climate research programme at the Environmental Change Institute and who co-organised the conference, chair a plenary discussion on what we can expect from the IPCC special report on 1.5C, due in 2018.
And rounding off the conference, Prof Achim Steiner, former executive director of the United Nations Environment Programme and new director of the Oxford Martin School, gave an optimistic closing speech.
Here is a selection of the some of Steiner’s final points: