摘要:采用高分辨率卫星和再分析资料，利用涡旋探测技术、滤波和合成分析等方法，对夏季北太平洋副热带地区中尺度海洋涡旋与大气的耦合关系进行了分析。结果表明：在日时间尺度上，海洋涡旋的海表温度（Sea SurfaceTemperature，简称SST）与海表风速之间不仅存在同位相的正相关关系，还存在反位相的负相关关系，即在涡旋这种中尺度上既存在海洋对大气的强迫，也存在大气对海洋的强迫。海表风速与SST同位相时，对暖（冷）涡来说，向上（下）的净热通量增强，云和降水增多（减少）；其海水温度异常和海流旋度较强，暖（冷）涡较为深厚，一定程度上表明了海洋对大气的强迫。海表风速与SST反位相时，对暖（冷）涡而言，当其处在正（负）位势高度异常、中低层相对湿度较小（大）、气温较高（低）的大气配置下，海表风速较小（大）；同时向下（上）净热通量增强，云和降水减少（增多）；涡旋海水温度异常和海流旋度较弱，这种暖（冷）涡较为浅薄；表明晴空（阴雨）条件下有利于暖（冷）涡的维持，一定程度上反映了大气对海洋的强迫作用。
关键词:北太平洋副热带/
中尺度海洋涡旋/
海气关系
Abstract:A suite of high-resolution satellite and reanalysis data are used to investigate the coupling relationships between oceanic eddies and atmosphere over the subtropical North Pacific in the summer by means of eddy detection scheme and filtering and composite analysis. Results show that there are both positive and negative correlations between sea surface temperature (SST) and wind speed at 10 m over eddies on a daily time scale, which indicates that not only oceanic but also atmospheric forcing exists in mesoscale oceanic eddies. When SST is in phase with sea surface wind speed for warm (cold) eddies, upward (downward) net heat flux enhances, total cloud cover and precipitation increase (decrease); the sea water temperature anomalies and current curls enhance, and thus warm (cold) eddies are relatively stronger. All of these changes indicate the ocean-to-atmosphere forcing to a certain extent. In addition, when SST is in opposite phase with sea surface wind speed for warm (cold) eddies, downward (upward) net heat flux enhances, total cloud cover and precipitation decreases (increases) with positive (negative) anomalies of geopotential height and air temperature at the low-middle levels, and negative (positive) anomalies of relative humidity. Moreover, the sea water temperature anomalies and current curl are weakened, and warm (cold) eddies are relatively weaker. All of these are conducive to the maintenance of warm (cold) eddies under clear (rainy) sky, indicating the atmosphere-to-ocean forcing to a certain extent.
Key words:Subtropical North Pacific/
Mesoscale oceanic eddies/
Air-sea relationship
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