That falls under a number of strategies for Solar Radiation Management [https://en.wikipedia.org/wiki/Solar_radiation_management], which, as you say, doesn't address the core CO2 concentration problem, but it might buy us time.
Personally, I like the idea of Marine Cloud Brightening. Getting 1 or 2 thousand ships spraying seawater into the air seems tractable, if not trivial.
Personally, I like the idea of Marine Cloud Brightening. Getting 1 or 2 thousand ships spraying seawater into the air seems tractable, if not trivial.