Imagine a large seaweed farm floating in the South Atlantic between Africa and South America.
It sucks a billion tonnes of carbon out of the atmosphere every year and then sinks it to the ocean floor so that it won't harm the ocean.
It's far-fetched. It might be possible. A British businessman has a plan to have this up and running by the year 2066.
Reducing the world's emissions won't be enough to limit global warming, according to scientists. Carbon capture schemes have been relatively low-scale.
They need to be attractive to investors if they are going to succeed.
John thinks he has a good idea. He wants to use the floating seaweed sargassum to make money. He's confident that his floating farm will be able to moderate the effects of climate change by drawing enough CO2 from the air.
New Zealand's largest city is at 21,200 sq miles. It needs to be a lot to make a difference in the amount of carbon dioxide pumped into the atmosphere. The amount of carbon the mega farm aims to capture annually is a billion tonnes.
The project is currently road-testing its technology in the Caribbean and Mexico and is inspired by the ideas of a marine Biologist. He has been fascinated by the potential to grow seaweed in huge rotating ocean currents.
He says that they collect all sorts of stuff. The plastic garbage is accumulating in the middle of the gyres.
Seafields plans to grow sargassum like islands of floating plastic.
The sargassum can't escape because the gyre stops them. It will only grow there if the right conditions are created. It will either die off or fail to grow if it escapes from our farm.
He needed to be correct. The Caribbean's tourism industry has been affected by sargassum for a long time. A foul stench is created when it washes up on the coast. It's not the best place to relax on the beach.
Seafields is certain that this won't happen with their seaweed. The team plans to feed their crop by syphoning water from the ocean depths.
The surface water trapped in gyres is very salty and low in vitamins and minerals. Prof Smetacek calls gyres the oceans' deserts.
The deserts glide over the ocean layer that the professor wants to draw to the surface to sustain the sargassum.
"If you connected the deep water with pipes, the water will flow up from the bottom and keep flowing forever," says Prof. Smetacek.
The team is working on technology. It's going to be a close one. The recreated salt fountain is nowhere near the scale of Seafields plans.
Prof. Smetacek predicts a bumper crop of sargassum if the salt fountain scales.
They have a high growth rate. He says that they double their energy use every ten days. A combine harvester is the best way to harvest seaweed.
Prof Smetacek thinks floating harvesters will bale the crop up and then send it down to the depths of the sea floor, where there isn't much oxygen. The seaweed has carbon in it. The team believes they can sequester captured carbon for a long time.
Seafields' financial backers are hoping that sargassum will bring in money as well. They want to sell credits for captured carbon. Businesses that can't easily cut their emissions can buy these credits to make up for it.
The rush to monetise CO2 capture has led to backers overselling technologies that eventually fall short of their stated aims, according to carbon market critics. Will Seafields' plan work in the lab and in the wild?
"I would want more data, more research, before I would say that you're going to get that kind of gigatonne-scale removal," says Dr.
The scheme itself could have a profound impact on biological systems. Can Seafields contain a lot of seaweed? Is the fountain strong enough to deal with all conditions?
If plastic tubes got set adrift by a big Atlantic storm, people would not be very happy.
She says there are simpler ways of nudging nature, such as growing more trees and protecting habitats that hold carbon. She says that we need to not keep it up there. Fossil fuels should be left in the ground. It's much easier to leave it in the ground than it is to try and capture it.
Some elements of the process are not yet proven, but John believes it is worth the risk.
He says that he sees riskier things on a daily basis.
The climate crisis can be solved by us. If everyone thought that way, no one would be able to come up with solutions of this scale.
All Rights Reserved © 2024
