So , no comment on the observation comparing the 2 warming step changes then.No explanation?
No explanation on how CO2 would warm sea water?
How can it ,when I.R. from CO2 can only penetrate sea water by a few microns.No one argues that.
Solar radiation penetration is measured in meters, and is what warms the water.
Anybody who ever had a swimming pool knows you need sunny days to warm it up, after the sky clouds over  ,in a day or so ,it cools off again ,not to forget the heat loss at night.
here is a lecture from Columbia U.
"Solar Radiation: Much of the direct and diffuse solar short wave (less than 2 micros, mostly in the visible range) electromagnetic radiation that reaches the sea surface penetrates the ocean (the ocean has a low albedo, except when the sun is close to the horizon), heating the sea water down to about 100 to 200 meters, depending on the water clarity."
see:http://eesc.columbia.edu/courses/ees/climate/lectures/o_atm.html Ocean-Atmosphere Coupling