Chinese Journal of Oceanology and Limnology

, Volume 28, Issue 5, pp 1112–1118 | Cite as

Factors influencing the climatological mixed layer depth in the South China Sea: numerical simulations

  • Conghui Fan (范聪慧)
  • Juanjuan Wang (王娟娟)
  • Jinbao Song (宋金宝)
Article

Abstract

The mixed layer depth (MLD) in the upper ocean is an important physical parameter for describing the upper ocean mixed layer. We analyzed several major factors influencing the climatological mixed layer depth (CMLD), and established a numerical simulation in the South China Sea (SCS) using the Regional Ocean Model System (ROMS) with a high-resolution (1/12°×1/12°) grid nesting method and 50 vertical layers. Several ideal numerical experiments were tested by modifying the existing sea surface boundary conditions. Especially, we analyzed the sensitivity of the results simulated for the CMLD with factors of sea surface wind stress (SSWS), sea surface net heat flux (SSNHF), and the difference between evaporation and precipitation (DEP). The result shows that of the three factors that change the depth of the CMLD, SSWS is in the first place, when ignoring the impact of SSWS, CMLD will change by 26% on average, and its effect is always to deepen the CMLD; the next comes SSNHF (13%) for deepening the CMLD in October to January and shallowing the CMLD in February to September; and the DEP comes in the third (only 2%). Moreover, we analyzed the temporal and spatial characteristics of CMLD and compared the simulation result with the ARGO observational data. The results indicate that ROMS is applicable for studying CMLD in the SCS area.

Keyword

mixed layer depth (MLD) South China Sea (SCS) wind stress net heat flux evaporation precipitation regional ocean model system (ROMS) 

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Copyright information

© Chinese Society for Oceanology and Limnology, Science Press and Springer Berlin Heidelberg 2010

Authors and Affiliations

  • Conghui Fan (范聪慧)
    • 1
    • 2
  • Juanjuan Wang (王娟娟)
    • 1
    • 2
    • 3
  • Jinbao Song (宋金宝)
    • 1
    • 2
  1. 1.Institute of OceanologyChinese Academy of SciencesQingdaoChina
  2. 2.Key Laboratory of Ocean Circulation and Waves (KLOCAW)Chinese Academy of SciencesQingdaoChina
  3. 3.Graduate University of Chinese Academy of SciencesBeijingChina

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