Seaweed and ice: a scientist’s weapons against climate change

Australian scientist and writer Tim Flannery argues our only hope is to develop new ways to use and store carbon in the earth’s natural systems
<p>One analysis shows that if seaweed farms covered 9% of the ocean they remove all current human emissions from the atmosphere. (Photo:&nbsp;</p>

One analysis shows that if seaweed farms covered 9% of the ocean they remove all current human emissions from the atmosphere. (Photo: 

A global deal to cut greenhouse gas emissions or geoengineering initiatives to cool the planet: these two options tend to dominate current thinking about climate change.

But Australian palaeontologist turned writer and activist, Tim Flannery, argues there is a “third way” that is almost entirely neglected in political negotiations and public debate.

In his latest book, “Atmosphere of Hope: Searching for Solutions to the Climate Crisis”, Flannery explains how this involves capturing carbon dioxide from the atmosphere and storing it in natural systems or using it to create things we need.

He told chinadialogue that in the coming decades investment in third-way technologies will make the green energy revolution look insignificant.

chinadialogue (CD): You’re clear that whatever happens in Paris we’re not going to come away with a strong enough deal to cut emissions fast enough and yet your book is optimistic about the future. Where does this hope come from?

Tim Flannery (TF): This hope comes from an understanding that there is an unused tool in the tool kit that we haven’t yet factored in yet. There are these technologies – that are very nascent at the moment – but that could make a difference to our climate future. No serious exercise looking at emissions reductions suggest we can keep the world below 2 degrees Celsius (2C) now – we’ve left it too late.

CD: Does this 2C target still make sense?

TF: If you look at the science now a case could be made that we should stay within a 1.5 degree rise. For example, the Australia’s Great Barrier Reef ceases to exist above 1.5 degrees – conditions will simply become too acidic and too hot. But we’re already committed to a 1.5 degree rise – the gas to produce this temperature is already in the air.  Two degrees is also unavoidable because we can’t change our energy systems fast enough. So it’s a political benchmark loosely based on science, but reality has intervened and we can no longer achieve this with emissions reductions alone.

CD: You make a distinction between geoengineering and third way technologies – what’s the difference?

TF: I’m terrified by geoengineering proposals. These proposals seek to cool the planet by either modifying the amount of sunlight reaching the earth (solar radiation), or have potentially very dangerous side effects like ocean fertilisation. These proposals either offer sticking-plaster solutions or draw carbon dioxide out of the atmosphere with severe unintended consequences.

So you can imagine that it is very tempting to have an initiative that puts sulphur into the atmosphere that would cool the earth instantly, and it is relatively cheap. It’s like the broad, easy road to hell.

There are four research teams in China working on these proposals right now.  You can imagine the temptations facing China looking down the barrel at very severe climate destabilisation, but the consequences would be catastrophic – not least geopolitical destabilisation. There is no treaty regulating geoengineering so it would be unilateral action with very severe consequences for China’s neighbours, let alone the rest of the world. All climate models suggest that if you put sulphur in the air this will affect the South Asian monsoon [among other consequences].

Third-way technologies, on the other hand, are approaches, methods or technologies that simulate the earth’s own system of carbon drawdown or regulation – to simulate or enhance it. A good example is the weathering of silicate rocks – a really important part of the earth’s mechanism to reduce CO2. So if we speed up the weathering of these rocks then we are stimulating the earth’s capacity to absorb CO2. In comparison with geoengineering, these technologies are not immediate in their effect and require decades of investment to start showing results but they deal with the problem at its source. This is like the narrow difficult road to heaven.

CD: The US and many other countries are also investing in a range of geoengineering projects from cloud seeding to advanced sulphur. What stage are these research projects at?

TF: For advanced sulphur there was a research programme in the UK called SPICE Project, which aimed to demonstrate the mechanism to deliver sulphur into the stratosphere. There is still investment going into this and every year these technologies become cheaper and more feasible. It’s certainly within the range of a wealthy individual today to alter the climate using these technologies and there is no regulatory regime in place to stop them from doing that. So I think [geoengineering is] becoming more real and scary by the day.

CD: Which of these technologies would put your money on?

TF: Can I answer this by taking a step back. We are in an extremely privileged position in that we know the problem the world will be trying to solve by 2050. The existing gas in the air, let alone new emissions, will be driving ever more adverse changes to the climate system. We know the scale of the problem – we have to draw 18 gigatonnes [of carbon dioxide equivalent out of the air] to reduce concentrations to one part per part million [from the 400ppm reached in 2015].

There are a series of options out there that we can look at. They range from desktop studies of sequestration of CO2 in the Antarctic ice cap through to well-known approaches such as reforestation. None of them have the scale to be a silver bullet – one exception might be seaweed farming, but that’s a desktop project at the moment.

I don’t know which of these technologies is going to work out – it will probably be a broad array of them. Funding and R&D mechanisms vary greatly. The race is on and it will make the clean tech revolution look small in comparison in terms of investment.

For people who think its looks like science fiction, I say that our imagination is the limiting factor here. 2050 will be very different from 2015.

CD: You say these technologies use natural processes, but natural processes can be very destructive – there have been mass extinctions in the past because of natural changes to the carbon cycle, for example. What are the big concerns around mass storage of carbon in natural systems?

TF: There are huge unknowns and this is why we have to start investing heavily in R&D now. Let’s take a couple of examples. Two of the most promising approaches at scale are really a new take on carbon capture and storage. One involves precipitating carbon dioxide snow in the Antarctic and storing in the icepack. It’s pretty simple, but there are caveats: what happens to earth’s system if you create concentrated CO2 depressions in the Antarctic? How stable is storage mechanism at scale?

Oceanic storage of CO2 is another example. We know CO2 will remain stable under a column of water 3 kilometres deep and we know that seaweed farming has helped. We’ve got 500 square kilometres of seaweed farm off the Chinese coast but there are still so many unknowns. Will the CO2 stored be stable? What are the economics of using bio digesters in seaweed farms and pumping this stuff down?  

CD: What’s China’s role in terms of innovation and funding?

TF: China is run by engineers and they are very good at picking technologies. China’s investment in cloning gives you a sense of how important a role they play. My hope is that China will ask its academies of science and engineering and others where their national interest lies in this enormous field of third way tech development. I can outline areas where China has a particular advantage. They are the largest seaweed farmer in the world – they understand seaweed farmers better than anyone else.  Then there the manufacturing carbon fibre from atmospheric CO2 – the George Washington University has just put forward. China could become the world’s leading manufacturer of carbon fibre, which will have a huge impact on emissions as it becomes cheaper and competes with steel and aluminium. Producing plastics from CO2 is another area. I know China is not at the technological forefront of these developments yet, but their experience with solar Photovoltaic shows you how they can buy into technological advances and build a manufacturing base.

Tim Flannery is the author, most recently, of the forthcoming book “Atmosphere of Hope: Searching for Solutions to the Climate Crisis.”