علوم غیرزیستی دریا
Masoud Sadrinasab; Abbas Einali; Mohammad Akbarinasab; Mohammad Ali Najarpour
Abstract
Arvandrud River Plume which is the main source of fresh water in the Persian Gulf and in addition its catchment area is settlement for about 54 million people is one of the most important phenomena in costal zones. . The river is the boundary line between Iran and Iraq and its plume extended in Iran, ...
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Arvandrud River Plume which is the main source of fresh water in the Persian Gulf and in addition its catchment area is settlement for about 54 million people is one of the most important phenomena in costal zones. . The river is the boundary line between Iran and Iraq and its plume extended in Iran, Iraq and Kuwait territory in Persian Gulf. Oceanographic studies are infeasible in the river and in its mouth due to geographic, politics, and security problems in the region. Despite the lack of in-situ data, this study is a serious step to the investigation to river plume. In this study salinity, temperature and water circulation of Persian Gulf were simulated by using oceanographic hydrodynamic model, FVCOM. Then, effects of wind and river discharge on structure of Plumes were investigated. For this purpose, 14 wind and 8 river discharge conditions have been used. The results show the river has a surface-advected plume that is highly affected by wind. The river plume area decreased with increasing wind speed. Three types of plumes were formed by different wind conditions, at the mouth of the river. Plume type 1 diverted toward the northwest coast of Persian Gulf and plume type 3 diverted toward the Kuwait coast. Plume type 2 was almost straight and was not diverted to the sides. The T-S diagram of surface water mass was very similar to all three modes, as a result, the plume shape and displacement is affected by wind.
علوم غیرزیستی دریا
hakime moosazad; mohammad akbari nasab; Hossin Mashayekh Poul
Abstract
Three forcing processes can provide residual current: Tidal forces, wind forces, and density differences. Tidal residual current are created by tidal wave interaction with the structure of topography. In this study, two-dimensional model VOM-SW2d is applied In the barotropic and fully nonlinear to Pozm ...
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Three forcing processes can provide residual current: Tidal forces, wind forces, and density differences. Tidal residual current are created by tidal wave interaction with the structure of topography. In this study, two-dimensional model VOM-SW2d is applied In the barotropic and fully nonlinear to Pozm Bay in the northern coast of Oman to simulate the tidal residual currents. In this study aimed to investigate the effects of substrate unevenness, removed topography slope using high-pass filter. Regular computational grid has been used with a resolution of 150 m, in direction x and y. The results obtain the maximum current velocity of 0.05 m/s near the mouth of the Gulf of Pozm. Tidal residual current was observed of topographic features near the headland of Pozm Bay, headland at Pozm Bay and also in coastal areas due to the slope of the coast. Also the model results shows several eddies in different sizes and some Circulation in various scales. Tidal residual currents in the Pozm Bay, as depicted by Lagrangian trajectories reveal a stationary flow whit several eddies. Each eddy can be identified with a topographic obstacle. This confirms that the tidal residual flow field is strongly influenced by the nonlinear interaction of the tidal wave with the bottom relief which, in turn, is deformed by figure hills and valleys beneath the seabed
علوم غیرزیستی دریا
Iman Khademi; Mohammad Akbarinasab; Abbas Ali Bidokhti; Mohammad reza Khalilabadi
Abstract
Turbulence is a form of movement characterized by an irregular or agitated motion. Turbulent motions are very common in nature. Most flows in the lower atmosphere and in the upper ocean are turbulent. The Turbulence has long had a special attraction for physicists and mathematicians; it has been called ...
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Turbulence is a form of movement characterized by an irregular or agitated motion. Turbulent motions are very common in nature. Most flows in the lower atmosphere and in the upper ocean are turbulent. The Turbulence has long had a special attraction for physicists and mathematicians; it has been called “the last great unsolved problem of classical physics”.In this study, hydrphysical measured data in the southern part of the Strait of Hormuz and with time step of half an hour during the period December 1996 to March 1998, by the University of Miami, and the meteorological station in island of Gheshm are used , then turbulence was simulated by General Ocean Turbulence Model (GOTM( . The results showed that, turbulent kinetic energy (TKE) in different seasons, with different penetration depths were appeared at during the year. In the cold season, the kinetic energy of the turbulent expands from surface to bottom and in the warm seasons because of existing the seasonal thermocline, depth penetration of TKE are limited, and only expands from surface to top of thermocline layer. In this study, investigation of the turbulent Prandtl number (Pr) shows that, effect turbulent viscosity Preference to the production buoyancy in the middle depth.