People usually mentions sea rise as the worst outcome of global warming, but extreme weather may be more pervasive, and that may be experienced far earlier than the sea level rise.
In any case, this is at best a mitigation, not a solution. It sounds like a simple enough idea, and may not have as a disruptive impact as other geoengineering proposals that may end having unexpected consequences. Some of the proposed flooded areas could have unique ecosystems that may be negatively impacted, but anyway all ecosystems are being negatively impacted right now, so a delay in the very bad trends we might be in could be positive overall.
In any case, this is at best a mitigation, not a solution. It sounds like a simple enough idea, and may not have as a disruptive impact as other geoengineering proposals that may end having unexpected consequences. Some of the proposed flooded areas could have unique ecosystems that may be negatively impacted, but anyway all ecosystems are being negatively impacted right now, so a delay in the very bad trends we might be in could be positive overall.