Verification and fitting for the results of mesoscale eddy detection based on the observed data
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摘要: 结合卫星高度计资料,本文在海洋中尺度涡旋综合识别法(综合法)的基础上,利用实测资料对识别的涡旋边界和中心点进行比对验证,得出以下结论:(1)通过诊断涡旋识别的边界切线与实测海流矢量的夹角,结果表明综合法识别的涡旋边界形态基本可以反映实测涡旋的水平形态;(2)利用实测海流和温度资料反演涡旋中心,通过与综合法识别的涡旋中心进行比对,结果显示涡旋识别的中心位置与反演的涡旋中心位置基本吻合。此外,通过比对圆与椭圆对识别涡旋的边界拟合效果,结果显示椭圆拟合准确率高于圆拟合准确率。Abstract: Based on the hybrid detection method for ocean mesoscale eddy, this paper uses the measured data to verify the detected boundary and center of eddy, and draws the following conclusions. (1) By diagnosing the angle between the detected boundary and the measured current vector, the results show that the detected boundary of eddy can basically reflect the current state of the actual eddy. (2) The center of detected eddy is compareed with the center that inversed by the measured current and temperature data. The results show that the detected center of eddy is basically consistent with the inversed center. Furthermore, by comparing the fitting effect of circle and ellipse to the detected boundary of eddy, the results show that the fitting accuracy of ellipse is higher than that of circle.
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Key words:
- mesoscale eddy /
- eddy detection /
- circle fitting /
- ellipse fitting
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图 5 基于实测数据的涡旋中心位置诊断过程
a. 实测流场确定涡旋中心线(蓝线);b. 200 m以浅平均温度确定涡旋中心区域(红圈);c. 观测站点200 m以浅温度剖面图;d. 涡旋中心线和中心区域确定涡旋中心位置范围(线段AB)
Fig. 5 Diagnosis processes of the eddy center based on observed data
a. The line (blue line) passing through the eddy center that diagnosed by observed current; b. the eddy core areas (red circle) determined by temperature that averaged shallower than 200 meters of each profile; c. temperature profiles that shallower than 200 meters of observed stations; d. region of the eddy center (line segment AB) determined by the line and the core areas
表 1 N01–N09号涡旋圆与椭圆拟合结果(OR、RR和α)
Tab. 1 The results (OR, RR and α) of circle and ellipse fitting for number N01 to N09 eddies
N01 N02 N03 N04 N05 N06 N07 N08 N09 平均 方差 OR(圆) 0.77 0.86 0.85 0.81 0.85 0.89 0.81 0.86 0.82 0.83 0.001 OR(椭圆) 0.95 0.90 0.88 0.87 0.87 0.92 0.83 0.81 0.88 0.88 0.001 RR(圆) 0.36 0.17 0.24 0.47 0.13 0.16 0.43 0.21 0.24 0.26 0.013 RR(椭圆) 0.09 0.17 0.20 0.29 0.11 0.13 0.11 0.30 0.18 0.17 0.005 α(圆)/(°) 32.8 17.3 27.1 36.0 17.6 14.9 27.4 25.5 31.1 25.5 49.0 α(椭圆)/(°) 10.3 15.4 21.6 23.1 14.1 8.0 15.9 21.2 25.3 17.2 31.0 -
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