Air‐Sea Turbulent Heat Flux Affects Oceanic Lateral Eddy Heat Transport.

Sea surface temperature anomaly (SSTA) of ocean eddies induces an anomalous air‐sea turbulent heat flux that acts to dampen SSTA. A two‐dimensional SSTA model explores the effect of air‐sea turbulent heat flux, parameterized as SSTA damping, in shaping eddy SSTA patterns. Increased SSTA damping transitions the SSTA pattern from a monopole to dipole, indicating the balance between eddy stirring of the background SST gradient and SSTA damping. The SSTA dipole pattern increases the correlation of eddy velocity and SSTA, but SSTA damping weakens the SSTA, resulting in an optimal damping rate maximizing lateral eddy surface heat transport. Globally, the SSTA damping rate increases toward the equator. In mid‐latitude and high‐latitude regions (e.g., the Kuroshio, the Gulf Stream, and the Southern Ocean), eddy SSTAs are monopoles, while the tropics and subtropics exhibit dipole SSTA patterns due to higher damping rates, facilitating greater lateral eddy heat transport when the SSTA is large. Plain Language Summary: Mesoscale ocean eddies, ranging from tens to hundreds of kilometers, exhibit distinct sea surface temperature anomaly (SSTA) patterns. In regions like the Kuroshio, the Gulf Stream, and the Southern Ocean, eddy SSTA exhibits a monopole pattern, with a single warm or cold core within the eddy. At lower latitudes, a dipole‐like pattern emerges, characterized by a pair of opposite‐sign SSTA surrounding the eddy. Previous studies attribute these SSTA patterns to the lateral stirring of background SST gradients by eddies. We develop a simplified SSTA model to highlight the role of eddy‐induced air‐sea turbulent heat flux in shaping eddy SSTA patterns. Eddy stirring of the background SST gradient generates SSTA, which induces anomalous sensible and latent heat flux that dampens SSTA. In the tropics and subtropics, effective SSTA damping balances the positive and negative SSTA generated by eddy stirring, resulting in a dipole‐like pattern. Conversely, at high latitudes, where SSTA damping is weaker, SSTA maintains its signature, yielding a monopole pattern. The transition from a monopole to a dipole pattern is facilitated by air‐sea heat flux, enhancing the correlation of eddy SSTA and velocity, while reducing SSTA variance, leading to an optimal damping rate that maximizes eddy heat transport. Key Points: Ocean eddies generate a dipole sea surface temperature anomaly (SSTA) pattern when air‐sea turbulent heat flux dampens SSTA counteracting eddy stirring of the background SSTThe dipole pattern enhances lateral eddy heat transport due to increased correlation between the eddies' horizontal velocity and SSTAThe SSTA damping rate due to air‐sea heat flux decreases toward the poles, maximizing lateral eddy heat transport in the subtropics [ABSTRACT FROM AUTHOR]