Hydrophysics

Hydrophysics

Modeling Thermohaline Front of the Persian Gulf Outflow in the Oman Sea

Document Type : Original Article

Authors
Eram ghazi 1
Mojtaba Ezam 2
Abbasali Aliakbari Bidokhti 3
Massoud Torabi Azad 4
Esmaeal Hasanzade 5
1 Department of Marine Science, Science and Research Branch, Islamic Azad University, Tehran, Iran
2 Department of Marine Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran
3 Institute of geophysics, University of Tehran
4 Department Physical Oceanography, Islamic Azad University, North Tehran Branch, Tehran, Iran
5 Isfahan University
Abstract
A three dimensional numerical model namely ROMS (Regional Ocean Modeling System) and observational data are used to study the thermohaline front of Persian Gulf Outflow in the Oman Sea. The simulation results show the formation of a thermohaline front at 80m depth in the direction of the north-east-southwest at the mouth of the Oman Sea. The seasonal thermohaline front variability was also identified, during winter a heat and salty tongue stretches from the Strait of Hormuz to the continental shelf along the south Oman coast. During summer, it shows a current departing from the coast moving forward to the middle of the Oman Sea. Thermohaline front is observed throughout the year, in summer as unified and patchy in winter. Intrusion of warm and salty water of Persian Gulf into the Gulf of Oman displays a local increase in salinity in the middle layers in 150-450m and 100-400m depths in winter and summer respectively which expresses two boundaries in the upper and lower layers. Diffusive convection and salt fingering can be seen in both the upper and lower boundaries respectively. The complex ocean flow patterns are result of monsoons in the Oman sea area. During the winter monsoon, a single cyclonic gyre is often observed near 58◦E and during the Southwest monsoon in summer, a dipolar eddy near Ras al Hamra and an anticyclone’s gyre in 25°N are detected.
Keywords
Numerical modeling
Thermohaline Front
Double diffusion
Persian Gulf Outflow

Subjects

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  • Receive Date 03 September 2018
  • Revise Date 08 October 2018
  • Accept Date 21 October 2018