https://news.slashdot.org/story/22/09/19/0158204/refreezing-earths-poles-feasible-and-cheap-new-study-finds
The interesting question is if some nation (or corporation for that matter - it's only about 15% of Google's annual profits) wants to do this and some other nation doesn't want them to do this, what happens?
Example, Bangladesh decides it is worth $11b to get that seawater back into ice caps to save their country and Russia decides they would prefer to have open shipping lanes through the Arctic.
>>"not a substitute for decarbonization"
That is the Achilles Heel of all the temperature engineering methods - they don't do anything for, for example, ocean acidification. This was actually the original problem that got scientists going on seriously measuring carbon. Oceans were acidifying faster than projected and so they set up a global network of sensors (on Exxon tankers among other places). Before they considered atmospheric CO2 a real problem, they were worried about oceanic CO2 absorption.
Adding aerosols to bring temperature down is like applying an ice pack to the forehead of a patient with a serious infection. It may help, may dramatically reduce the damage the illness does, but it's not a cure.
>some other nation
Already happened at least once.
Test Flight for Sunlight-Blocking Research Is Canceled - The New York Times
https://www.nytimes.com/2021/04/02/climate/solar-geoengineering-block-sunlight.html
Bill Gates has been pushing the aerial dusting for at least a decade.
> Bill Gates
Well, yes, but he had to fall back to implanting chips via vaccine when his plan to implant them under the guise of fighting global warming failed.
> Bill Gates
Plus he gave us Windows ME.
White House pushes ahead research to cool Earth by reflecting sunlight
https://www.cnbc.com/2022/10/13/what-is-solar-geoengineering-sunlight-reflection-risks-and-benefits.html
A startup says it's begun releasing particles in the atmosphere, in an effort to tweak the climate | MIT Technology Review
https://www.technologyreview.com/2022/12/24/1066041/a-startup-says-its-begun-releasing-particles-into-the-atmosphere-in-an-effort-to-tweak-the-climate/