Abstract
An Archiving, Validation and Interpretation of Satellite Oceanographic data (AVISO) mesoscale eddy trajectory atlas product is used to analyze the path type and temporal variability of the eddies that entered the continental shelf area of the northern South China Sea (SCS) from 1993 to 2016. A total of 184 mesoscale eddies entered the continental shelf area of the northern SCS during a 24-year period. We classify the mesoscale eddies into four types according to the motion trajectories: along-the-isobath type, intrusion-of-continental-shelf type, local wandering type, and shelf-internal-generation type. The occurrence numbers of these four types were 87, 38, 23, and 36, respectively. The mean amplitude and radius of the along-the-isobath type are the largest, about 18 cm and 153 km, respectively; furthermore, their average lifetime is also the longest, about 93 days. The mean amplitude, radius, and lifetime are the smallest for the shelf-internal-generation type, about 16 cm, 146 km, and 74 days, respectively. The direction and velocity of the background flow field affects the intrusion path of the mesoscale eddies onto the continental shelf of the northern SCS. The seasonal distribution of the mesoscale eddies quantity is also related to the direction and velocity of the corresponding background flow field.
Highlights
Ocean mesoscale eddies are long-term close-circulation regions within the ocean [1,2,3]
The number of cyclones was 88, which accounted for 47.8%
One can see the following features: (1) The mean number of the mesoscale eddies is about eight, which means that one eddy would intrude into the study area every 1.5 months, (2) the spectra for temporal distribution of the number of eddies peaked at periods of 2–3 years, which shows a significant inter-annual variation, (3) the number of cyclonic eddies that invaded the study area in 1994, 1997, 2003, 2010, 2011, and 2015 is two, which is less than the average, (4) there is an excessive number of anticyclonic eddies in 1997, 2000, 2009, and 2011
Summary
Ocean mesoscale eddies ( called oceanic vortices) are long-term close-circulation regions within the ocean [1,2,3]. Mesoscale eddies exist widely throughout the global ocean [6,7], and their energy is higher than the background flow field for an order of magnitude [8]. Using temperature and salinity data, Wang et al [19] observed an anticyclonic warm eddy located in the southwestern part of Taiwan Island They considered that the eddy originated from the Kuroshio intrusion. Under the control of the monsoon and the general circulation, complex and variable ocean dynamic processes occur in the northern shelf area of the SCS; understanding these is essential to the study of the dynamic marine environment of the SCS. The temporal distribution of the mesoscale eddies is analyzed, as well as their paths
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
