Solar geoengineering

[Robert Chris]

Dear Editor

The opposition to solar geoengineering covered in today’s Editorial is an excellent example of a little knowledge being a dangerous thing.  The risks of a global climate meltdown eloquently and authoritatively explained at last week’s National Emergency Briefing to UK politicians and others, cannot be averted by decarbonisation alone.  This is not a failure of political will or egregious profiteering by the supposedly nasty fossil fuel lobby.  It’s driven by the inescapable laws of physics.

Carbon dioxide happens to be an extraordinarily inefficient agent of temperature change.  For example, if we removed 10 gigatonnes of atmospheric CO₂ (10GtCO₂) in one go in 2027, global surface temperature would be a mere 0.1^oC lower by 2050 than it would otherwise have been.  10Gt is the weight of water it would take to fill 10,000 Wembley Stadiums.  This is an utterly infeasible amount of carbon removal for an insignificant short-term benefit.

You might not like the idea of solar geoengineering; I don’t like it, indeed, I’ve long maintained that it’s a crazy idea.  But in the world we’ve now created, if you had any grasp of the numbers you’d like no solar geoengineering an awful lot less.  Solar geoengineering is now essential for a secure climate future.  That’s the physics talking.

That is not to say it’s risk-free.  But our past inaction, now means there are no risk-free options.  We have limited time to do the research to ensure the next generation of decision makers can deploy it at scale in the safest, most equitable way.  And to be clear, this is alongside aggressive decarbonisation, not instead of.

But if you cleave to a solution to climate change in which there are no losers, you’ll make humanity as a whole an even bigger loser even sooner.

Regards
Dr Robert Chris 
Associate of Centre for Climate Repair at Cambridge and Visiting Fellow at The Open University (the views expressed above are personal.  I do speak on behalf of either of these academic institutions.)
20 Grove Hill House
Tunbridge Wells
TN1 1SA

07976 262808

[Robert Chris]

Apologies - typo - missing 'not' in signature block which should read 'I do not speak on behalf of either of these academic institutions.'

Regards

Robert