The temperature of the troposphere is constantly being affected by variations in the rate of energy flow from the oceans driven by internal ocean variability, possibly caused by temperature fluctuations along the horizontal route of the thermohaline circulation and by variations in energy flow from the sun that affect the size (and thus density) of the atmosphere and the rate of energy loss to space. (newclimatemodel.com)
That of course has nothing to do with SST, the mysterious internal ocean oscillations, the sun or anything but CO2. (judithcurry.com)
The existence of that cooler layer is evidence that the rate of evaporation is the primary influence on variability in the rate of ocean energy loss (apart from internal ocean circulation variability which is not relevant here) and it follows that more evaporation for the same rate of conduction and radiation (from a stable temperature differential) will send that cooler layer deeper and / or intensify the temperature differential between it and the ocean bulk below. (newclimatemodel.com)