# Can we really prevent all warming for less than 10B$ with the mostly side-effect free geoengineering technique of Marine Cloud Brightening?

If we're to believe the [Philosophical Transactions of the Royal Society](https://royalsocietypublishing.org/doi/full/10.1098/rsta.2012.0086), or the [Copenhagen Consensus Center](https://www.copenhagenconsensus.com/copenhagen-consensus-climate/results), or apparently any of the individual geoengineering researchers who've modelled it, it's possible to halt all warming by building a fleet of autonomous wind-powered platforms that do nothing more sinister than spraying seawater into the air, in a place no more ecologically sensitive than the open ocean, and for no greater cost than 10 billion USD

(edit: I'm not sure where the estimate of 10B came from. I saw the estimate of 9B in a lot of news reports relating to CCC, and I rounded up to be conservative, but I couldn't easily find CCC materials confirming this number)

If this works, no significant warming will be allowed to occur after the political static friction that opposes the use of geoengineering is broken.

Isn't any amount of mean warming bad? So shouldn't we deploy something like this as soon as possible? Shouldn't we have started deploying it years ago?

Side effects seem minimal. Relative to seeding clouds with sulpherous chemicals (which will also be considered, once the heat becomes unbearable), it leaves no ozone-eliminating residue, it produces no acid rain. It may disturb rainfall in some regions, but it seems that it may be viable to just avoid seeding too close those regions.

I want to make it clear how little support this needs in order to get done: 10 billion USD is less than a quarter of the tax income generated by the nation of just New Zealand one year. A single tiny oecd government could, in theory, do it alone. It wont need the support of a majority of the US. It probably wont require any support from the US at all.

What should we do with this information?

I do buy the claim that public support for any sort of emission control will evaporate the moment geoengineering is realised as a tolerable alternative. Once the public believe, there will never be a quorum of voters willing to sacrifice anything of their own to reduce emissions. I think we may need to start talking about it anyway, at this point. Major emitters have already signalled a clear lack of any real will to change. The humans will not repent. Move on. Stop waiting for humanity to be punished for its sin, act, do something that has some chance of solving the problem.

Could the taboos against discussing geoengineering delay the discovery of better, less risky techniques?

Could failing to invest in geoengineering research ultimately lead to the deployment of relatively crude approaches with costly side effects? (Even if cloud brightening is the ultimate solution to warming, we still need to address ocean acidification and carbon sequestration, and I'm not aware of any ideal solution to those problems yet, but two weeks ago I wasn't aware of cloud brightening, so for all I know the problem isn't a lack of investment, might just be a lack of policy discussion.)

Public funding for geoengineering research is currently non-existent in the US (All research in the US is either privately funded or funded by universities), and [weak in China](https://www.technologyreview.com/s/608401/china-builds-one-of-the-worlds-largest-geoengineering-research-programs/) (3M USD. 14 members, no tech development, no outdoor experiments.)