The eddy northwest of Luzon Island in South China Sea

The Kuroshio intrusion into the SCS through the Luzon Strait is an important process. Because of the intrusion, an eddy is located northwest of Luzon Island. Many papers reported the eddy. However, the eddy was claimed to be either cyclonic or anticyclonic. Based on the P-Vector inverse method, the circulation field is calculated from the GDEM data, and the eddy is identified as cyclonic in the upper layer and as anticyclonic in the lower layer. The results suggest that the anticyclonic eddy originates from Kuroshio intrusion, and the cyclonic eddy is due to the South China Sea Warm Current.