what is this now, a quadruple negative?

It is untrue that they have no idea if the "solutions" we try won't lead to worse outcomes

It is true that they have some idea that the "solutions" we try won't lead to worse outcomes

It is true that they have some idea that the "solutions" we try will lead to better outcomes.

I think the nuance needed here is: what do we mean by "better outcomes?" It's reasonable to believe that it will help lower temperatures. But is that an "outcome" in and of itself?

If we consider the "outcome" to also include the second and third order effects, I'd like to understand how anyone could be certain that it will be better.

> In the early 1990s, anthropogenic sulfur dominated in the Northern Hemisphere, where only 16% of annual sulfur emissions were natural, yet amounted for less than half of the emissions in the Southern Hemisphere.

> Such an increase in sulfate aerosol emissions had a variety of effects. At the time, the most visible one was acid rain, caused by precipitation from clouds carrying high concentrations of sulfate aerosols in the troposphere. At its peak, acid rain has eliminated brook trout and some other fish species and insect life from lakes and streams in geographically sensitive areas, such as Adirondack Mountains in the United States. Acid rain worsens soil function as some of its microbiota is lost and heavy metals like aluminium are mobilized (spread more easily) while essential nutrients and minerals such as magnesium can leach away because of the same. Ultimately, plants unable to tolerate lowered pH are killed, with montane forests being some of the worst-affected ecosystems due to their regular exposure to sulfate-carrying fog at high altitudes.[1]

Sure, let's have ~2 years of that.

[1] https://en.m.wikipedia.org/wiki/Sulfur_dioxide

The way to do it is to release the SO2 directly into the stratosphere, where it stays for ~2 years, and does not affect rain, which happens far below.

One of the risks of a strategy like this is that we become reliant on it and use it as an excuse to solve the actual problem slower. Then if there's ever any disruption to SO2 production we get 20 years of warming all at once that we otherwise might have worked to avoid.

Betting on never having a disruption to that supply seems high risk to me.

Ending fossil fuel usage and removing the excess CO2 will take at least 50 years.