Interannual variability of summertime cross-isobath exchanges in the northern South China Sea: ENSO and riverine influences

Song, Yunping; Lin, Yuxin; Zhan, Peng; Liu, Zhiqiang; Cai, Zhongya

doi:10.5194/os-21-3361-2025

Articles | Volume 21, issue 6

https://doi.org/10.5194/os-21-3361-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/os-21-3361-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 21, issue 6

Research article

|

10 Dec 2025

Research article |

| 10 Dec 2025

Interannual variability of summertime cross-isobath exchanges in the northern South China Sea: ENSO and riverine influences

Yunping Song, Yuxin Lin, Peng Zhan, Zhiqiang Liu, and Zhongya Cai

Supplement

https://doi.org/10.5194/os-21-3361-2025-supplement

Data sets

ERA5 monthly averaged data on single levels from 1940 to present H. Hersbach et al. https://doi.org/10.24381/cds.f17050d7

Global Ocean Gridded L4 Sea Surface Heights And Derived Variables Reprocessed 1993 Ongoing EU Copernicus Marine Service Information https://doi.org/10.48670/moi-00148

NOAA coral reef watch version 3.1 Daily 5 km satellite sea surface temperature, updated daily NOAA Coral Reef Watch https://coralreefwatch.noaa.gov/product/5km/index_5km_sst.php

Short summary

To study summer coastal current changes in the Northern South China Sea (NSCS), we analyzed 2000–2022 observations and simulations, focusing on El Niño–Southern Oscillation (ENSO) and Pearl River freshwater impacts. During El Niño, uneven sea levels between the central and southern South China Sea strengthened northward currents. The Pearl River’s freshwater plume extended farther east, reducing nearshore salinity. Our findings highlight how local and remote factors interact to shape NSCS circulation dynamics.