Can Asteroids, Geoengineering Save Earth? #AfricaClimateCrisis

University of Cape Town (UCT) Vice-Chancellor Professor Mamokgethi Phakeng has unpacked eco-regeneration and geoengineering with experts as possible solutions to save our planet from global warming and ecosystem disruption.

The director of the Climate Risk Lab at UCT's African Climate and Development Initiative, Dr Christopher Trisos, explained that eco-regeneration is about restoring damaged and degraded ecosystems while geoengineering suggests that we could offset global warming with technologies that deal with the symptoms.

"An example is stratospheric aerosol injection, whereby we would spray tiny particles into the stratosphere to form a thin veil to reflect some sunlight back to space, thus [offsetting] some global warming," said Trisos.

Eco-regeneration often utilises tree-planting to offset carbon emissions. However, Trisos pointed out, in the wrong place, tree-planting can have negative effects on people and ecosystems. "In the context of climate change, a lot of people talk about planting trees. In an African context, this is something we have to be careful about. Tree-planting is not a silver bullet solution," said Trisos.

Dr Adriana Marais, a theoretical physicist with a PhD in quantum biology and the director of the Foundation for Space Development Africa, feels that some of our solutions lie somewhere between Mars and Jupiter, on the moon and in the earth's orbit.

"The asteroid belt is between Mars and Jupiter - this is an interesting resource of metals, minerals and water ... The motivation to look to the asteroid belt as a source of metals and minerals is because we cannot continue to harvest resources on Earth the way we do. Mining is one of the ways we contribute to the disruption of ecosystems," said Dr Marais.

She pointed out that space resources are responsible for giving us power and water. "Much of the water on our planet was delivered from space via asteroids and comets. Power and water are fundamentally space resources," Marais added.

This contrasts the opinion of Professor Bruce Hewitson, South Africa national research chair on climate change and director of the Climate System Analysis Group, who in August 2021 said: "I'm deeply sceptical of geoengineering, not because it's not feasible, but because it has very dangerous potential consequences. I think it is very valid to do research on it so we understand geoengineering options better. So doing research to look at its limits and viabilities is very valid, but I am deeply sceptical that it will ever be a viable option."