EGU2020-1751
https://doi.org/10.5194/egusphere-egu2020-1751
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Impact of the Equatorial Wind Stress on the Indian Ocean Shallow Meridional Overturning Circulation During the IOD Mature Phase

Linfang Zhang1, Yaokun Li2, and Jianping Li3
Linfang Zhang et al.
  • 1College of Global Change and Earth System Sciences (GCESS), Beijing Normal University, Beijing 100875, China (1147984953@qq.com)
  • 2College of Global Change and Earth System Sciences (GCESS), Beijing Normal University, Beijing 100875, China (liyaokun@bnu.edu.cn)
  • 3Key Laboratory of Physical Oceanography-Institute for Advanced Ocean Studies, Ocean University of China and Qingdao National Laboratory for Marine Science and Technology, Qingdao 266100, China(ljp@bnu.edu.cn)

            This paper investigates the impact of the equatorial wind stress on the Indian Ocean Shallow Meridional Overturning Circulation (SMOC) during the India Ocean Dipole (IOD) mature phase. The results show that the equatorial zonal wind stress directly drives the meridional motion of seawater at the upper level. In normal years, the wind stress in the Indian Ocean is easterly between 30°S-0°and the westerly wind is between 0°and 30°N, which contributes to a southward Ekman transport at the upper level to form the climatological SMOC. During the years of positive IOD events, abnormal easterly wind near the equator, accompanying with the cold sea surface temperature anomaly (SSTA) along the coast of Sumatra and Java and the warm SSTA along the coast of East Africa, brings southward Ekman transport south of the equator while northward Ekman transport north of the equator. This leads the seawaters moving away from the equator and hence upwelling near the equator as a consequence, to form a pair of small circulation cell symmetric about the equator.

How to cite: Zhang, L., Li, Y., and Li, J.: Impact of the Equatorial Wind Stress on the Indian Ocean Shallow Meridional Overturning Circulation During the IOD Mature Phase, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1751, https://doi.org/10.5194/egusphere-egu2020-1751, 2019