Surface flux changes explain why oceanic air warms more than water

Climate models consistently simulate that near-surface air warms more than near-surface water over the global ocean. This represents a change in near-surface temperature gradient and may be thermodynamically important. Long-term observational global temperature records are built from measurements of air temperature over land and water temperature over oceans, so different air-water warming can also affect model-observation comparisons. Here I show that ocean heat uptake does not explain why the air warms more, rather it can be explained as a combination of CO2-forced atmospheric adjustments followed by feedback-driven evaporation increases. Through this understanding, the surface-temperature discontinuity is ultimately linked to hydrological sensitivity and therefore the global atmospheric energy budget.