When we’re out in the sun it’s nice to be able to sit in the shade to cool off. And now scientists have figured out a way to create a giant sunshade in the sky to cool off our planet. If it works it could be a solution to global warming.
It sounds like a futurist novel plot, but the future is here now. The new technique being explored by scientists all over the world — from Harvard to Bangladesh — is called solar geoengineering.
In layman’s terms, solar geoengineering involves using balloons or jets, to create a man made atmospheric sunshade that would protect the most vulnerable countries against the negative impacts of global warming.
For a long time scientists have known that the earth could be cooled when temporary or man made shade is created by pollution in the atmosphere, smoke from forest fires and smoke from volcanic eruptions.
To create SCoPEx, the scientists would use a balloon to release aerosols at a height of 12 miles, at the upper end of the Earth’s atmosphere. Their theory than these aerosols will change the reflective properties of cloud cover and thus reflect the heat of the sun is controversial, to say the least.
The cooling effect of “ship tracks” – narrow artificial clouds of pollution, created by emissions from ships — has been known to scientists for many years. Ship tracks have more small water drops in them than clouds normally have. This makes the pollution-created clouds brighter and more reflective of sunlight, which cools the earth.
“Solar geoengineering – injecting aerosol particles into the stratosphere to reflect away a little inbound sunlight – is being discussed as a way to cool the planet, fast,” the Harvard scientists wrote.
“Solar geoengineering is outlandish and unsettling. It invokes technologies that are redolent of science fiction – jets lacing the stratosphere with sunlight-blocking particles, and fleets of ships spraying seawater into low-lying clouds to make them whiter and brighter to reflect sunlight. Yet, if such approaches could be realized technically and politically, they could slow, stop or even reverse the rise in global temperatures within one or two years.”
“The technique is controversial, and rightly so,” they add. “It is too early to know what its effects would be: it could be very helpful or very harmful. Developing countries have most to gain or lose. In our view, they must maintain their climate leadership and play a central part in research and discussions around solar geoengineering.”
Dr Atiq Rahman, director of the Bangladesh Centre for Advanced Studies said that countries like his were especially at risk.
“Clearly [solar radiation management geoengineering] could be dangerous, but we need to know whether, for countries like Bangladesh, it would be more or less risky than passing the levels of excessive global warming. This matters greatly to people from developing countries and our voices need to be heard. The overall idea of solar geoengineering is pretty crazy, but it is gradually taking root in the world of research,” said Rahman.
Global warming and the resulting climate change has caused droughts, floods and monsoons that have harmed developing countries. If something can be done by scientists to save these countries, then it needs to be tried. And if it works it will benefit all of mankind.