Rethinking climate change mitigation

From extreme temperatures to rising sea levels, the effects of climate change are becoming ever more obvious – and the need to act ever more urgent.

“I'm going to start with a very bold statement. What we do, as humanity over the next five to 10 years, will determine the future of humanity for the next 2000. Our civilisation is now very much at risk,” Sir David King, the founder and chair of the Centre for Climate Repair at Cambridge University and chair of the Climate Crisis Advisory Group, proclaims in a recent Found In Conversation podcast.

“It's a massive … challenge. And there's not one bit of the planet that's not affected.”

The warming of the Arctic Ocean has already led to significant shifts in the world’s wind systems, in turn causing extreme weather events. At the same time, melting ice caps are pushing up sea levels, threatening wildlife and human habitats. The permafrost also contains methane, which is released into the atmosphere as the ice melts.

Although at the current pace it will take many decades for all of the Earth’s ice to melt, the impact will start to be felt much sooner, he explains. 

“Should we worry now? Let me take you to one of the low-lying countries of the world, Vietnam. If this continues, which it looks likely to, [Vietnam] is going to be under sea water at least once a year, for 90 per cent of the landmass,” King says.

And the impact will be felt far beyond Vietnam’s own borders: “This is the third biggest rice producer in the world. And once the land has been salinated, rice production will be extraordinarily difficult.”

“We're talking about a massive challenge not only to living space for human beings but it's also food production for the whole world at risk.”

Reduce, remove, refreeze

To address the problem, Cambridge University’s Centre for Climate Repair proposes a blueprint focusing on the 'three R’s' – reduce, remove and refreeze.

“Deep and rapid emissions reduction, no argument, we must achieve that as quickly as possible. But the second thing is we need to remove excess greenhouse gases that are up … in the atmosphere that are causing these drastic actions occurring in the Arctic Circle region,” King says.

“And the third thing is – and this I know will bring a smile to your faces as something impossible – we have to learn how to refreeze the Arctic to buy time, while we reduce emissions and remove excess greenhouse gasses.”

Phytoplankton to the rescue

When it comes to removing existing emissions, the challenge is to do it at low cost and at scale. Here, King and his colleagues are investigating one novel solution that would also have other benefits for planetary health.

“What we're working on is 72 per cent of the world's surface …  which is the oceans.”

Ocean ecosystems depend on phytoplankton – microscopic marine algae which provide food for fish and absorb carbon dioxide. The problem is that phytoplankton grows on floating beds of whale excrement, and that material is in short supply due to shrinking whale populations.

“A simple idea we had was, why don't we just make artificial whale poo and spread it on the surface of the ocean?,” King says.

The artificial excrement could be be made of nitrates, phosphates, silicates, and iron. This will then be floated on a raft created from rice husks – a throwaway product in rice production, providing a platform on which phytoplankton can grow.

“I think this has the possibility of removing something like more than two to 3 billion tonnes [of carbon] a year, and perhaps 10 billion tonnes of greenhouse gases a year. If we were able to cover 2-3 per cent of the world's ocean surface every year in the way I've described,” King says. 

“I believe that if we do this, the baleen whale population will regrow. And then we can sit back and let them do it as long as we ban whaling.”

Cool clouds

That will then leave the third “R” – refreezing the Arctic. Here, too, scientists are investing a potential solution.

“White clouds reflect sunlight away from the surface of the earth. If you are underneath the white cloud, it's going to be cooler than if the cloud isn't shading you . And it's a very big difference,” King says. “So what we want to do is cover the Arctic Circle region with white clouds for the three polar summer months.”

Taking inspiration from natural formation of clouds, the plan is to create droplets of ocean water and spray them above the ocean where, with the help of wind, they will turn into clouds.

So possible solutions are on the horizon, but that doesn’t lessen the urgency of action, argues King.

“Each one of us is a part of the problem ...  because we have all been very short-term in our thinking,” he concludes. “We're talking about the mid-term future. It's not 100 years away. It's right there for our children and my grandchildren.”

If you would like to hear more, listen to Climate Crisis - Climate Solutions Found in Conversation podcast episode where we welcomed Sir David King, Sian Sutherland, the co-founder of A Plastic Planet, a global campaign aimed at reducing plastic pollution; and Ari Helgason, a climate technology investor who is passionate about finding and funding innovative solutions to the climate crisis.

Insights for investors

In order to achieve net zero emissions by 2050, governments, businesses and individuals around the world will need to spend an extra USD105 trillion, estimates McKinsey. That's equivalent to USD3.5 trillion per year over the next 30 years.

Each USD1 invested in the green economy transition, on average, yields USD4 in benefits, World Bank analysis shows.

Sustainable bond issuance could reach USD4.5 trillion per year, globally, according to research from the IIF.