Mesoscale processes make the largest contribution to ocean variability and are significant agents in ocean heat transport. In this investigation, we provide evidence based on satellite observations for an increasing trend in surface transient eddy heat flux (EHF) over the period 1993–2020. The enhanced EHF is particularly prominent in western boundary currents and their extensions at mid-latitudes, with increases of 20%–40% per decade. Additionally, we decompose the EHF trend into contributions from velocity variance, temperature variance and a coherence parameter using a Cauchy–Schwarz inequality. We find that each contributes to the spatial pattern of the trend in EHF, with the contribution from enhanced temperature variance dominating the global zonal mean EHF trend over the past few decades.

中文翻译：

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在过去三年中观察到的海洋表面极地涡流热通量的增加趋势

中尺度过程对海洋变率的贡献最大，是海洋热传输的重要因素。在本次调查中，我们根据卫星观测提供证据，证明 1993 年至 2020 年期间地表瞬态涡流热通量 (EHF) 的增加趋势。增强的 EHF 在西部边界流及其在中纬度的延伸中尤为突出，每十年增加 20%～40%。此外，我们使用 Cauchy-Schwarz 不等式将 EHF 趋势分解为速度方差、温度方差和相干参数的贡献。我们发现，每一个都有助于 EHF 趋势的空间模式，在过去几十年中，温度变化增强的贡献主导了全球纬向平均 EHF 趋势。