| 摘要: |
| 基于观测和再分析数据，利用时空滤波、动态合成等方法，研究了1993?2019年热带西北太平洋中尺度涡对海气界面热交换的调制作用。结果表明，反气旋涡(气旋涡)伴随的海表温度暖(冷)异常能导致海气温差加大(减小)，进而增强(减弱)蒸发，从而增加(减少)海洋向大气释放的热通量。同时，上述海气变量异常值由涡旋中心向外逐渐减小，变化规律类似指数型高斯函数分布。中尺度涡引起的海表温度异常是导致海气温差、蒸发率和热通量异常的关键因素：对于反气旋涡，海气温差异常、蒸发率异常、感热通量异常和潜热通量异常与海表温度异常的线性拟合系数分别为0.91、48.2 cm·yr?1·℃?1、11.6 W·m?2·℃?1、38.3 W·m?2·℃?1，而对于气旋涡，相应的线性拟合系数分别为0.77、37.5 cm·yr?1·℃?1、10.0 W·m?2·℃?1、36.8 W·m?2·℃?1。分析表明，反气旋涡对大气的影响更为显著。这一结果不同于黑潮延伸体及南海的研究结果：在黑潮延伸体，反气旋涡和气旋涡对大气的影响相当，而在南海，气旋涡对大气的强迫效应更为显著。本研究给出了热带西北太平洋中尺度涡对海气界面热通量的强迫特征，并明确了海气热通量的关键影响因素，强调了与其他海域的显著差异，为深入研究中尺度涡与海气耦合过程提供了重要依据。 |
| 关键词: 热带西北太平洋 中尺度涡 海气热交换 热通量 |
| DOI：10.11693/hyhz20240900200 |
| 分类号: |
| 基金项目:国家重点研发计划 |
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| Study on the impact of mesoscale eddies on air-sea heat exchange in the northwest tropical pacific from 1993 to 2019 |
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LiXuhui, ZhaiFangguo, LiuYikuan
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Ocean University of China
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| Abstract: |
| Based on observational and reanalysis data, this study employs spatiotemporal filtering and dynamical compositing methods to examine the modulation of air-sea heat exchange by mesoscale eddies in the tropical Northwest Pacific from 1993 to 2019. The findings indicate that anticyclonic (cyclonic) eddies are associated with warm (cold) sea surface temperature (SST) anomalies, which lead to an increase (decrease) in the air-sea temperature gradient, thereby enhancing (reducing) evaporation and subsequently increasing (decreasing) the heat flux from the ocean to the atmosphere. These anomalies in air-sea variables decrease gradually outward from the eddy center, following an exponential Gaussian-like distribution. SST anomalies induced by mesoscale eddies are identified as the primary driver of variations in the air-sea temperature gradient, evaporation rate, and heat flux. For anticyclonic eddies, the linear regression coefficients between SST anomalies and anomalies in the air-sea temperature gradient, evaporation rate, sensible heat flux, and latent heat flux are 0.91, 48.2 cm·yr?1·℃?1, 11.6 W·m?2·℃?1, 38.3 W·m?2·℃?1, respectively. For cyclonic eddies, the corresponding coefficients are 0.77, 37.5 cm·yr?1·℃?1, 10.0 W·m?2·℃?1, 36.8 W·m?2·℃?1. The analysis suggests that anticyclonic eddies exert a more pronounced influence on the atmosphere compared to cyclonic eddies, a finding that contrasts with studies in the Kuroshio Extension and the South China Sea, where cyclonic eddies have a more significant forcing effect. This research elucidates the forcing characteristics of mesoscale eddies on air-sea heat flux in the tropical Northwest Pacific, identifies the critical factors influencing air-sea heat flux, and underscores the regional differences in these processes, providing an important foundation for further investigation into mesoscale eddy-air-sea coupling mechanisms. |
| Key words: Northwest Tropical Pacific mesoscale eddies air-sea heat exchange heat flux |