Houston we have problem

[a completely inoffensive name]

I'm interested in hearing about the ups and downs of geo-engineering again.

I have actually read of a few theoretical geo-engineering ideas that don't sound *that* far-fetched.One of them were a fleet of cheap long vertical tubes that pumped cold water from below up to the surface to cool surface temperatures down. They were powered by extracting energy from the waves if I remember correctly. Not exactly practical but not a giant space mirror to reduce the sunlight hitting the earth.Also, idk if this counts as geo-engineering but there were trials (I think) with artifical cloud seeding to promote water droplet formation and rain in dry areas.