As the world grapples with different strategies to mitigate the warming climate, few have sparked such controversy in recent times as solar geoengineering.
The proposed plan would use aerosols, fired into the stratosphere with high-flying aircraft, to cool the planet by blocking radiation from the sun.
It would essentially mimic the effects seen after volcanic eruptions – but, an analysis published at the beginning of this year warned that the approach could have grave consequences.
If the plan to artificially cool Earth were abruptly stopped, the experts warned it could trigger extreme warming at rates far more dramatic than the current climate is changing, in a phenomenon known as the ‘termination shock.’
But now, some scientists have hit back, arguing that the risk might not be as it seems.
Solar geoengineering would use aerosols, fired into the stratosphere with high-flying aircraft, to cool the planet by blocking radiation from the sun. It would essentially mimic the effects seen after volcanic eruptions – but, it has remained a controversial topic
In a new paper published to the journal Earth’s Future, a pair of researchers from the Institute for Advanced Sustainability Studies in Potsdam, Germany and the John A Paulson School of Engineering and Applied Sciences at Harvard University explain that the current analyses focus on the worst-case scenario.
And, while termination shock would be catastrophic, it could mostly be avoided by taking a few simple precautions.
‘Most studies so far have focused on the extremes, like in a large-scale deployment that’s ended instantly and permanently,’ explains co-author Peter Irvine, of Harvard’s engineering school, in a video about the work.
‘If solar geoengineering were deployed at small scales, say cooling only a few tenths of a degree Celsius, then if it were ended there wouldn’t be substantial warming.
‘If it were phased out over the course of decades, there would not be a rapid warming, so that would also not constitute a termination shock.
‘And if it were turned off for some reason and then turned back on again, the termination shock could be avoided.’
Aerosols will remain in the stratosphere for months after their deployment has ended, giving a large window of time to restart the process before the shock takes hold, the researcher notes.
As the world grapples with different strategies to mitigate the warming climate, few have sparked such controversy in recent times as solar geoengineering. File photo
Given the magnitude of the plan, many countries and a lot of money would be involved.
And, this means strong incentives for a backup plan, according to the researcher.
Termination shock would have dramatic effects on society and species around the world, triggering rapid climate changes that could drive everything from terrorism and economic collapse to natural disasters.