In this spontaneous conversation between two of Britain’s most vocal scientists on climate change and engineering, we see a frank analysis of the details that belie inconvenient truths for each one us……

Our current carbon pollution rate is taking us towards a planet that is on average 4ªC warmer than today with regional variations far exceeding this and changes to the natural world that will be so profound that it is fair to say, this will not be the same planet.

Carbon sequestering technologies

Anderson: “Carbon sequestration works at very small levels. Whether you could scale it up to 35 billion tonnes… this is where you suck the CO2 either out of the atmosphere or out of chimneys from power stations and then you store this as liquid CO2 somewhere for the next thousand plus years. To store this quantity of CO2, this is a huge challenge. Yet, this is normalised in almost all of the models that are advising policymakers… every single scenario that has been discussed, at this event in Paris that I have heard, assumes, without actually mentioning it up front, that this technology works. It is highly speculative!”

Carbon Budget

One of the big omissions from the Paris Accord is the mention of the carbon budget. Anderson discusses why this is so important. The remaining 900 billion tonnes that analysts say we can burn before exceeding the carbon budget for safe climate change (a figure that should not be taken as absolute fact, but rather, based on ‘scenarios’ that are themselves dependent on carbon negative technologies, that currently do not exist, and emissions reductions that should have started years ago) is meant to be divided up in a fair and equitable way, placing emphasis on the world’s poor to give them a better quality of life and resilience to climate changes in their region.

By taking out the mention of the carbon budget in the early stages of the Paris negotiations, the implication is that the conversation over who burns what can be sidestepped and the wealthy nations do not have to tackle this central issue straight on.

It is worth adding to this that achieving 1.5ºC as a safe limit of global mean temperature rise to ensure the safety of exposed regions (such as low lying lands and small island states), is only possible with aggressive and immediate decarbonisation over the next ten years. Thus, the number is only being treated as “aspirational” and not realistic.

Anderson: “The problem with carbon, it is in the dyes in my shirt. It is in the ship that brought my shirt here, it’s how we got to this event, it keeps the lights on, it’s keeping your computer running. Carbon is completely pervasive.”

The +2ºC world

Anderson: “It is highly unlikely that we will hold to 2º Centigrade. It is a choice. We know how to do this today but it does require this social and political change in the short-term.”

The reality of the issue is that we are losing the window of opportunity to stay below 2ºC. As we start looking to a 2-4ºC world, we are looking at planet that is likely to be wrought with famine, conflict, overwhelming migration and huge degradation of natural systems.

There are worrying feedbacks to warming the planet that should concern us all. One example is the collapse of global forests. A scientific study has shown that at 2.5ºC increase in temperature many of the worlds forests will collapse. These are huge carbon sinks and sources of oxygen. The world without trees is certain to be challenging.

Of course, we can add in all kinds of other impacts such as the collapse of ice sheets, melting permafrost, dying off of oceans, and they are all severely bad for life on Earth.

Social values and climate justice?

Hunt: “So, why is the mood here quite optimistic? It seems to me we may well have passed some tipping points. Time will tell in the next few decades.”

Anderson: “Part of the optimism comes from rich people in the northern hemisphere who think we can buy our way out of it…. you hear people use this kind of language… what this means is, ‘we’ll muddle through because we are rich enough to buy our way out of it, and the poor will die!’ If you look at the language we use and peel away the layers, and look beneath it, what we are saying is fairly savage!”

Hunt: “This is the modern version of ‘Let them eat cake’. We seem to be accepting that our lifestyles will not change very much. Somehow we have to put in a political framework, a legal framework, a governance framework to solve the problem, without affecting our lifestyles.”

“Geoengineering” the climate

Anderson: “Personally, my view on this is that we should do the research on these techniques and we should do the research on the techniques for sucking the CO2 out of the air, but all of our policy framing should assume they don’t work. So it is an insurance policy that has a very high probability of never paying out. So we should do the research and assume that they will never work. The problem is that we are not doing very much research and we are assuming that they work.”

Hunt: “The research that I have been involved in on the SPICE project (Stratospheric Particle Injection for Climate Engineering), a small test that we want to do, had to be stopped because of the concerns about the perception of what we were doing. It was not because of the concerns about what we were actually doing, but about the perception of what we were doing.”

“I think that this is a bit worry that the perception of what we are doing in pumping 35 billion tonnes of CO2 in the atmosphere seems not to be of any great concern, but the perception of research we might do into climate engineering is of great concern. I’m not saying that it is not a great concern but let’s get a balance.”

Anderson: “I take the view that we can actually make a big difference by making social changes now. We can still just make the 2ºC but it needs rapid and deep reductions by this relatively small set of big emitters. Because we are saying we’re not prepared to do that, therefor we have to think about the other sets of issues. I think we do need to reinvigorate the debate about social change in the short to medium term, whilst we put the low carbon energy supply in place.”

“All these other techniques are contentious and they may not work. If we could reduce our energy consumption today, that is not everybody on the planet but just a relatively small number of us. Then that definitely would have an impact on our carbon emissions very quickly.”

Optimism?

Hunt: “We are coming into a period of great stress. I think that our young kids at school now are going to be our new generation of inspirational people. I am not just relying on them rather hopefully. I just believe that the world we are going into will be very stressful and that people will rise to the challenge and great things will happen.”

Anderson: “I think we have all the tools we need to resolve this problem, pretty much at our fingertips, but we are not prepared to use them now. And the two I have mentioned are: Very significant social change for the few in the short to medium term, and engineers doing what engineers have been very good at doing for decades, if not centuries, and that is changing our infrastructure towards a very low carbon future going forward.”

“If you put those two together I think that 2ºC is still a viable goal for our society.”