Dear Laurie,
Thanks for your excellent talk and responses to questions [1]. As you said, the geopolitical opposition to SAI has to be analysed.
A few politicians are in denial about climate change; one of them (Trump) has accepted the conspiracy theory about SRM and mad scientists. But most politicians will have been told that SAI is extremely risky or even off the table. (John Holdren, as a chief scientific adviser, had said it was "on the table" [2], but received such opprobrium that he had to retract the statement.) The question is how to bring politicians round to the reality that (i) SAI responsibly deployed could prove extremely benign, and (ii) only SAI has a chance to halt the Arctic meltdown, reverse climate change, slow sea level rise, and save corals, rainforests and other vital ecosystems. The risk/risk analysis is a no-brainer. Only a prompt deployment of SAI can prevent the world being committed to inexorable and irreversible climate change, sea level rise and biodiversity loss. That is what an engineering assessment tells you. And the window of opportunity is closing rapidly.
To get SAI accepted, we have to combat the web of lies and half-truths created by the acknowledged climate experts, whose reputations depend on SAI not being deployed for the foreseeable future. These experts, determined that emissions reduction should be seen as the solution to climate change, have been pumping up fear of SAI, which is easy to do since most people think of SO2 as a nasty pollutant.
We also need a consortium of the willing: countries willing to support SAI deployment including some countries who might actually carry out the initial deployment to lower the Arctic temperature. This consortium would take charge of modelling, monitoring and governance: ensuring responsible and optimised deployment. Under Trump and Putin, the USA and Russia cannot be trusted, especially since both countries are determined to exploit a melting Arctic.
Cheers, John
Systems engineer and research scientist
Chair of the Planetary Restoration Action Group (PRAG)
[2] John Holdren was President Barack Obama's longest-serving Science Advisor and Director of the Office of Science and Technology Policy (OSTP). During his tenure, he famously advocated that geoengineering "should not be off the table" in climate discussions, while noting it required extensive research to understand potential risks.