The summer-fall anticyclonic eddy west of Luzon: Structure and evolution in 2012 and interannual variability
Autor: | Shuqun Cai, Xia Wang, Rongyu Chen, Wendong Fang |
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Rok vydání: | 2017 |
Předmět: |
geography
South china geography.geographical_feature_category 010504 meteorology & atmospheric sciences 010505 oceanography Continental shelf Empirical orthogonal functions Aquatic Science Sea level anomaly Geostrophic velocity Oceanography 01 natural sciences Acoustic Doppler current profiler Anticyclone Climatology Trough (meteorology) Ecology Evolution Behavior and Systematics Geology 0105 earth and related environmental sciences |
Zdroj: | Journal of Marine Systems. 172:84-92 |
ISSN: | 0924-7963 |
Popis: | The Conductivity–Temperature–Depth (CTD) and acoustic Doppler current profiler (ADCP) measurements along 18°N off the western Luzon in the South China Sea (SCS), collected during a cruise from August 12–14, 2012, were used to explore the vertical structure of an anticyclonic eddy (AE) during the observational period. Further, the French Archiving, Validation and Interpretation of Satellite Oceanographic data (AVISO) sea level anomaly (SLA) and corresponding anomalous surface geostrophic velocity were used to study the temporal evolution of the AE. The vertical structure of the AE along 18°N in August 2012 showed a trough located near 117.5°E. The AE extended vertically downward and its distinct feature was identifiable to 200 m depth. Seasonal variations of SLA indicate that the AE lasted for 5 months (June to early November), going through the growth and nearly stationary period from mid-June to late August and then propagating westward along 18°N with varying phase speeds and shapes to the continental slope off the southeastern Hainan Island during late September to November. Furthermore, T–S characteristics suggest that the AE was generated off the western Luzon. Interannual variations of the summer (July–September) SLA presented by Empirical Orthogonal Function analysis, indicates that the local circulation was enhanced by the anomalous anticyclonic eddy along 18°N in the years of 2008, 2010, 2012 and 2013 during the period from1993 to 2014. |
Databáze: | OpenAIRE |
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