Well, just how much has the Earf warmed, as of right now?
The UN Climate Panel says 1.5 degrees Celsius. It’s true. The data can be difficult to find, as the propagandists (News web sites) ALWAYS says what it will be next year, next ten years, by 2050, or 2100 or so.
I’d ask these people, how much cooling do you intend to cause? Give us the number in degrees. If you can’t say, then stop.
Ask them for their business case with data and project plan. Then watch the brains go poof.