Assessment of three eddy detection methods based on high-resolution reanalysis of ocean current data in the South China Sea
Based on 11-years of daily high-resolution reanalysis of current data,three eddy detection methods,i.e.,the Winding Angle(WA)method,the Vector Geometry(VG)method,and the Okubo Weiss(OW)parameter method,are used to detect and track mesoscale eddies in the South China Sea.The detection capabilities of the three methods for mesoscale eddies are compared,and their applicability in high-resolution reanalysis products is analyzed.It has shown that the improved spatial resolution of the product can amplify the W-parameter noise of the OW method,which makes the method characterized by eddy over-detection and eddy splitting phenomena,leading to a higher eddy number,a smaller eddy radius,and the lowest average successful detection rate of eddies(76.2%).Compared with the OW method,the WA method reduces the eddy's excessive detection rate and the missing detection rate to a certain degree,and the average successful detection rate of eddies improves to 85.1%,but the eddy identification takes longer.The VG method has an average eddy successful detection rate of up to 93.2%compared to the previous two methods,combined evaluation parameter(excessive detection rate×missing detection rate÷successful detection rate)has a significant advantage(4.5%),and the computation is efficient.Therefore,the VG method has more reasonable eddy detection results and better applicability when using it for mesoscale eddy identification based on high-resolution reanalysis products.
mesoscale eddy detectionalgorithm assessmenthigh-resolution reanalysis dataSouth China Sea
NETL
NSTL
万方数据
