Also this link explains the warmer deep water:

https://en.m.wikipedia.org/wiki/Circumpolar_deep_water

There are ways to capture CO2 from the air but going through CaO is not practical as it is produced from CaCO3.

IFAIK here CaO is used as a Co2 carrier, not a one time use material.

You accumulate CO2 via CaO and then release it via heat provided from the thermal system to go back to CaO. The CO2 is then turned into hydrocarbons. Closed loop. The infrastructure is already in place for hydrocarbons at least until we get to a hydrogen infrastructure. Then you can carbon capture till your heart's content.