فهرست مطالب vahid chegini

In this research, physical parameters (temperature, salinity and density) of Chabahar bay seawater were obtained from a project as "Study of Seasonal Variations of Physical Parameters Trend of the Chabahar Bay (Phase IV: 2011 & 2012)" was investigated. The parameters were measured in 9 stages from October 2011 till Aug 2012 in a network consisting of 24 stations (11 inside and 7 outside stations). The parameters were measured by CTD device from surface to seabed of all stations. According to the results of this research, seawater temperature in the hot season is higher than cold season from bottom to surface in all stations. A thermocline layer forms in deep southern areas during summer and vanishes in winter. The entering flow of Oman Sea water into the Persian Gulf, which is less salty than that of the Persian Gulf, is maximized during the hot season and minimized in the cold season. This less salty flow affects the salinity of Chabahar bay water such that its rate is more during the cold than the hot season. The summer monsoon (Stormy weather and rough sea) significantly affects the physical parameters of Chabahar bay's water. During this time, the surface layer extends deeper and the thermocline close to the bed of the bay.

Arvandroud is the most important and only navigable river in Iran. It is where the river flows into the sea and the flow velocity is drastically reduced, causing the deposition of suspended sediments and reducing the depth of the confluence of the river and the sea. This decrease in depth at the entrance of the Arvandroud is such that it has restricted the entry of high-capacity vessels, and its dredging seems necessary to supply water to vessels on this international waterway. In the present study, the effect of dredging the Arvand estuary and also constructing an earthen pier in the Arvandkenar position on the physical parameters of flow velocity and water level fluctuation has been simulated.

For simulation, Mike 21.3's three-dimensional hydrodynamic model was used in two dimensions. This model performs based on the irregular triangular meshing approach and the main computing platform of the model is the HD module, which is based on the numerical solution of 2 and 3-dimensional Navier-Stokes average equations for the non-compressible state, taking into account Bozinsky and hydrostatic pressure. Equations of continuity, momentum, temperature, salinity and density are also considered. In the initial settings, the initial conditions of the model, consisting of temperature and salinity, are uniform for the whole field at 25 °C and 32 psu, respectively. Initially, the water level and flow velocity in the whole basin were considered zero. Due to the small width of the river, the wind effect has been ignored. The model has a sea boundary downstream and a river boundary upstream. Temperature and salinity at the sea border were applied by nesting method from the mother model of the Persian Gulf to the daughter model. The time series of water level fluctuation at the sea border was constructed from the four main components of the tide (M2, S2, O1, K1) related to the SHATT AL ARAB OUTER BAR and applied to the model. At the upper boundary of the river, the temperature and salinity were constant, and 26 ˚C and 2.39 psu were adjusted, respectively. At this limit, the water level fluctuation was adjusted so that the net discharge of the river was 600 m3/s.

In the validation stage, it was found that the result of the root mean square error test for water level fluctuation in Faw was 0.16 m, indicating good accuracy of the model results compared to field measurements. The results showed that if the Arvand mouth is dredged to reach a depth of 8 m and a width of approximately 300 m, the water level after dropping will drop to a maximum of 10 cm near the mouth, and the flow velocity in the dredged area will decrease. In addition, if 33% of the river section in Arvandkenar region is blocked, the difference in water level on both sides of the gorge will be up to 13 cm, and the maximum tidal velocity in the middle of the gorge will reach 0.57 m/s from 0.87 m/s in normal condition.

Dredging of the Arvandroud estuary reduces the flow rate in the dredging canal and this in turn increases sedimentation in the dredging canal. However, reducing the width of the river can compensate for this slowdown and prevent sedimentation. These two methods should be used in combination to reduce the maintenance costs of the channel.

The Khuran Channel, Southern Iran (26°45’N), is a topographically complex channel which is open at both ends. Owning to its particular geometry, this narrow channel is subjected to strong tidal currents.Across-channel distribution of the mean and tidal flows were obtained over a semidiurnal tidal cycle in the Khuran Channel where the highest tidal velocity in the third day of the secondary spring tide exceeded 140 cm/s. Velocity profiles were obtained using a 614.4 kHz Teledyne RDI Workhorse Broadband ADCP over 13 repetitions of a cross-channel transect. The 3.1 km long transect ran north/south across the channel.The M2frequencywas separated from the observed current using sinusoidal form functions and the least square regression analysis. Contrary to the previous study in this channel, the mean inflow observed in the deep parts of the channel and mean outflow occurs over the shallow slopes, with the maximum magnitudes (15-20cm/s) near the surface in the north side. The maximum lateral shear and convergence were found over slopes located between the middle and the north side of the channel.

The present research assessed spectral density function of Caspian Sea waves in Amirabad port by using the data derived from Iranian wave scan buoy. This buoy is set at the depth of 25 meter and registers seasurface oscillations at 4 Hz. At first Wave spectrum were extracted using Fast Fourier Transformation and the accuracy of Jonswapmodel on estimation of wave spectrum was determined and the results indicated that the model with default coefficients is inefficient in these port. As a result, optimum coefficients were extracted using the least squares method in curve fitting. Afterwards, the effect of bandwidth parameter n on model estimation accuracy was assessed and it was observed thatin narrow spectra (v<0/4), Krylov model was best efficient but in wide spectra (v>0/45), Neuman model yielded the best results for these spectra.The results obtained for the spectra between these two ends revealed that Jonswap model yielded the best results at these spectra. Generally it can be concluded that wave spectrum in south Caspian Sea have a good fitting with common models with considering of spectrum widths.

Tide is one of the most regular changes of seas and ocean levels which are offering particular importance due to the influence on the flow pattern. According to engineering and environmental needs in industrial economic zone of Persian Gulf, Strait of Hormuz and Gulf of Oman, knowing the tidal characteristics of these areas is important. Therefore FVCOM (ocean model) was used to stimulate the tidal amplitude in an area comprising Persian Gulf, Strait of Hormuz, Gulf of Oman and Arabian Sea. Finite volume method is used in this model to discretize the hydrodynamic equations on triangular mesh. Uniform mesh is used with a resolution of 5 km in the model.The constant values of eight diurnal and semidiurnal tidal components are prescribed along the open boundary. In order to validate the model results, after applying harmonic analysis on the model outputs in desired stations, the achieved amplitude of this analysis compared with results which are obtained from the analysis on the available measurement data in these stations. According to the measurement and model results in these stations, meanwhile identifying the four main tidal components, the amplitude pattern of these components was determined in the whole domain. Also, by using amplitude of main components and estimating of F factor, the type of tide was predicted in the study area. Moreover, studying the maximum amounts of tidal velocity in the study area shows that the amount of this velocity in the Gulf of Oman and Arabian Sea is less than 0.1 m/s.

Coastal classification is an effective method for investigating the reaction of coasts against such hydrodynamical factors as waves and tides. This method is also employed in integrated coastal zone management, especially shoreline management. Coastal classification models are of two kinds, equilibrium models, predicting the effects of constant incident waves on nearshore features such as bars and troughs, and morphologic state models, predicting the sequence of bar-trough shapes and scales under the varying influences varying waves. Wright and Short (1984) presented the most widely accepted beach classification scheme where three main beach states are identified, namely dissipative, intermediate, and reflective. Intermediate beaches are divided into four states, low tide terrace, transverse bar rip, rhythmic bar beach, and longshore bar trough.
In this paper, the beach states of the southern coasts (Hormozgan Province) of Iran were classified using Masselink and Short (1993) and Masselink and Hegge (1995) methods. Owing to its location, and abundant oil and gas resources, Persian Gulf is one important military, economic and political interest, hence the necessity of its investigation. We primarily studied different kinds of hydrodynamic forces dominating the beaches of the province. Six stations were chosen throughout the shoreline between 54˚39' 18" latitude and 26˚30' 29" longitude up to 53˚ 9' 39" longitude and 27˚4' 34" latitude. Next, the waves, tides, and sediments were evaluated in different depths in these stations via laboratory actions. We employed the wave data of 2002 from the modeling project (ISWM) which was done in the National Institute of Oceanography, and the sediment data of Hormozgan Province coast were gleaned from the Marine Geological Organization. In order to determine the general slope of the beach by Arc GIS software, hydrographic maps were used with approximately 1/100000, and the slope of each station was calculated. After that, through breaker height (Hb), the tide range (TR), wave period (T) and sediment fall velocity (Ws), two dimensionlessparameters, namely the relative tide range (RTR = TR/ Hb) and the dimensionless fall velocity (Ω = Hb/WsT,) were calculated in each station.
The results indicated that in the southern regions of Iran (Hormozgan Province), due to the tidal effects in and based on (3

Thirteen repetitions of a cross-channel transect in the Khuran Channel within the Strait of Hormuz allowed the description of the mean flow and semidiurnal tidal properties of a northsouth transect. Water velocity profiles were obtained with a 614.4 kHz TRDI Work Horse Broadband ADCP along this 3.3 km long transect on 10 October 2014, the third day of secondary spring tide. The M2, M4 and M6 frequencies were separated from the observed current using sinusoidal least squares regression analysis. The semidiurnal tidal currents along this transect exhibited typical amplitudes of 160-170cm/s, decreasing toward coastal waters. The mean flow which confirmed the occurrence of asymmetry between ebb and flood phase of tidal current in Khuran Channel were ebb dominant in the deeper part of the channel and southern slopes and flood dominant over the shallower areas, with greatest magnitudes (10 cm/s) near the surface mainly in the deeper parts of the northern side of the channel. The tidal current amplitudes decreased and for the most with depth and followed the bathymetry particularly in the middle of channel, which reveals the dominants of frictional forces. The large overtide amplitude is as a result of nonlinearities that were produced by increased frictional effects that lead to the asymmetry between ebb and flood phase of tidal current in this channel.

In this paper, we investigated the capabilities of SST data assimilation methods into FVCOM model using nudging scheme. In Data assimilation, observational data was combined with the numerical model in order to get the optimum model. This process was achieved by correcting the model errors for two first to optimize the desired variable and second to present the optimized initial condition for model. The studying domain was the Persian Gulf during 1998-2003. The model was run in two stages with the same setup: without and with assimilation method. To assess the impact of data assimilation, the model results in both runs were compared with valued OISST data in spatial distribution and temporal evaluation. The statistical parameter values were improved by using data assimilation. The surface temperatures of shallow parts were optimized specially near the Strait of Hormuz.

Thirteen repetitions of a cross-channel transect in the Khuran Channel within the Strait of Hormuz allowed the description of the mean flow and semidiurnal tidal properties of a north-south transect. Water velocity profiles were obtained with a 614.4 kHz TRDI Work Horse Broadband ADCP along this 3.3 km long transect on 10 October 2014, the third day of secondary spring tide. The M2, M4 and M6 frequencies were separated from the observed current using sinusoidal least squares regression analysis. The semidiurnal tidal currents along this transect exhibited typical amplitudes of 160-170cm/s, decreasing toward coastal waters. The mean flow which confirmed the occurrence of asymmetry between ebb and flood phase of tidal current in Khuran Channel were ebb dominant in the deeper part of the channel and southern slopes and flood dominant over the shallower areas, with greatest magnitudes (10 cm/s) near the surface mainly in the deeper parts of the northern side of the channel. The tidal current amplitudes decreased and for the most with depth and followed the bathymetry particularly in the middle of channel, which reveals the dominants of frictional forces. The large overtide amplitude is as a result of nonlinearities that were produced by increased frictional effects that lead to the asymmetry between ebb and flood phase of tidal current in this channel.

For calculating the acoustic pressure due to sound propagation at sea using usual methods (pressure variations signals), knowing the density distribution and consequently, changes the speed of sound in the environment is very important. Many environmental factors affect the distribution of the density at sea, depending on environmental conditions and geographical location and the weaknesses of each of them are different. One of them is internal waves which usually cause temporal and spatial changes and consequently affect the acoustic wave propagation in the ocean. Internal waves can be generated by tidal currents over sea floor sloping that is very common in the stratified oceans. Results of study in the some researches showed that internal waves can effected on sound waves in two ways: 1-Internal waves can be decrease sound level up to 25 dB due to sound mode coupling in an exact frequency. 2- Internal waves can fuscous and defocus sound waves because of sound speed fluctuation.
The purpose of this study is a laboratory investigation of internal waves caused by fluctuation of a cylinder in a stratified glass channel with 3 meters long, 0.5 meter width and 1 meter height, on the sound waves propagation. In this study, using the double bucket and filling box method for generating stratification that stratification can be measured by one pair of salinity and temperature meters fixed on a rail moved up and down. Using the usual methods of setting up internal waves and using acoustical transducers in 53 KHz frequency, internal wave's effects on the propagation of sound waves, were investigated. In this study with usual optical method (Synthetic Schlieren) internal waves generated in the tank can be detected. In this method Internal wave generated in the glass tank change optical index of water layers and cased deviation of Straight lines designed on the back of tank. Laboratory results showed that sound waves can be focused and defocused due to the normal modes of internal waves. Some 9 experiments were done mainly in cases withvertical linear density stratified fluid. As the modal structure of internal waves in the water tank change due to the waves, constant density surfaces change slopes, hence changing the sound ray's paths and the amount of signals reaching the receivers. Similar results of numerical simulation also show similar behavior in the strength of the acoustic signal. Numerical simulation modeled by AcTUP v2.2L software that use KERAKENC method based on normal mode method. The acoustic signal can be weakened up to 54 per cent depending on the degree of sound ray divergence. We can conclusion that in the laboratory tank in this study internal waves effects on sound waves by focusing and defocusing and not by mode coupling.
Similar behaviors can be expected in the open ocean as the existence of internal waves is ubiquitous. For this goal dimensionless numbers should be use. Bowen (1993) showed that for simulating a sound waves interaction with a phenomenon in laboratory scale we can use ka = ka'. With this formula we can compare laboratory results with real results on oceans.

Spatial measurements of conductivity, temperature and depth were used to study salinity variations along the principal channels of the tidal hypersaline creek network in the vicinity of Bushehr Port, Persian Gulf during three 25- tidal cycles in both warm and cold months.
Salinity variations and tidal fluctuations were out of phase throughout the short inverse estuary. The salinity values inside the creek were higher during the warm month (August 2014) than the corresponding values during the cold month (December 2014) due to the change in evaporation rates. The salinity values, also, were linearly increased longitudinally from the inlet to the head especially during warm season.
Observed evaporation rates in August and December periods and the corresponding salinity differences between hypersaline water of the creek and the incoming seawater were used to determine the Residence Time (RT).
The longitudinal variation of RT showed almost linear increase from the inlet to the head. The maximum temporal distribution of RT represented an increase from ~10 days in winter to ~30 days in summer due to the change in the longitudinal salinity gradient.

Predicting the quality of water and air is a particular challenge for forecasting systems that support them. In order to represent the small-scale phenomena, a high-resolution model needs accurate capture of air and sea circulations, significant for forecasting environmental pollution. Data assimilation is one of the state of the art methods to be used for this purpose. Due to the importance of thermal structure in monitoring the variations of environmental phenomena, the present study has used Sea Surface Temperature (SST) in data assimilation method to optimize this parameter. SST is one of the most important factors to conduct researches on the ocean, the atmosphere, and their interaction, not to mention monitoring and forecasting air and ocean phenomena as well as commercial and fishing communities and weather forecasts. This study has aimed to present a satellite-derived SST based on pathfinder advanced very high resolution radiometer (AVHRR) data assimilating in FVCOM (finite volume community ocean model) on the Persian Gulf to examine the effect of data assimilation by using the Cressman scheme. The performance of this method has been compared to the optimal interpolation SST (OISST) data, via both visual comparisons and statistical parameters. Applying assimilation method improves correlation coefficient of the model from 0.92 to 0.99. Results demonstrate that the modeled SST has been completely reconstructed by the data assimilated experiment via the Cressman scheme for this region. The spatial and temporal pattern of SST reveals a significant improvement in the entire domain during the investigated period in the gulf.

In this study, patterns of water current, sea surface temperature and salinity distributions over the South Caspian Sea (SCS) have been investigated using ROMS model. Appling the most accurate bathymetry data and forces with temporal resolution of 3-6 hours, and spatial resolution of 0.125 deg is a characteristic of the simulations used in this study. Results show that there is a barotropic anticyclonic eddy over the deep water of SCS, which extended from surface to subsurface. A dipole anticyclonic/cyclonic feature is another structure of SCS that located in northwest (in Apsheron sill)/ southwest respectively,a nd persist throughout the year. Based on results, net buoyancy flux of SCS is more affected by thermal buoyancy rather than haline buoyancy. In addition, there is a saline front in the east coast of SCS that is separated from other regions by combining with warm (cold) water during (warm) seasons.

This paper investigates the spatial and temporal changes of water physical parameters in the Strait of Hormuz. Temperature, salinity, and density measured and investigated for winter 2012, spring and summer 2013 by using CTD probe. Moreover, different water masses and layers were studied. The whole water column thermally, at most stations were completely mixed in the winter. Surface layer, namely mixed layer, is completely homogeneous in summer. Spring time is a transition state of water properties between winter and summer. Maximum changes of water column density were 2.0, 4.25, and 5.0 for winter, spring and summer, respectively. Water volume of Persian Gulf outflow change seasonally and sometimes Persian Gulf outflow was traceable near Iranian coast in spring. Based on this research, it seems that Persian Gulf outflow water volume was maxima in the spring time. Study of water masses in different parts of the Strait of Hormuz shows two different water masses in the eastern part of the strait. In summer, only two separate water masses were traceable in the central and western part of the Strait. It was also evident that, there were three-layers in the water column in summer. At the interface of water masses, fronts of different strengths depending on temperature and salinity gradients were formed. Salinity and sigma-t of Persian Gulf outflow in summer were more than those of winter

In this study, wave was simulated in the southern part of Caspian Sea using nested grids of SWAN model and utilizing ECMWF-ERAI wind data. Wave model was verified with the correlation of %94 comparing the modeled and measured data at Neka, Nushahr and Anzali stations. The simulations were repeated utilizing wind data used in ISWM II. Although, wind data used in ISWM II have been verified in the Caspian Sea, the higher spatial resolution of ECMWF-ERAI wind data resulted in a better prediction of the wave periods up to 1s and wave heights up to 0.5-1.5 m in the east and central parts of the southern Caspian Sea. However, the results of SWAN using ECMWF-Reanalysis INIO wind data were in a better agreement with the trend of measurements in west part of the Caspian Sea. Also, wind data used in ISWM II resulted in higher accuracy prediction of wave characteristic for measured wave heights less than 1.5 m.

In this study, the roles of different driving forces of circulation (or flow) pattern of the Caspian Sea surface have been evaluated using COHERENS (a three-dimensional hydrodynamic model) for the year 2004. The model is based on the hydrostatic version of the Navier-Stokes equations. The hydrodynamic part of the model uses the equations of temperature and salinity, and the momentum equations use the Boussinesq approximation, an assumption of vertical hydrostatic equilibrium, and the continuity equation. The equations of the model are discretised on an Arakawa C-grid. The equations of momentum and continuity that are solved numerically use the mode-splitting technique. In order to simulate the circulation of the Caspian Sea, the gridded fields were chosen as 0.046 × 0.046 degrees along the horizontal directions, which gave a grid size of about 5 km, and 30 sigma layers along the vertical axis. The model was set up for three different forcing configurations. First, the effects of only wind forcing were evaluated using some field observations of wind-driven currents. In the second cofiguration, only the river driving-force was evaluated by the model and the flow fields were obtained. Finally, in the last configuration, all driving-forces such as wind forcing, air pressure, air temperature, precipitation rate, cloud cover and humidity along the initial conditions including temperature and salinity of the basin were examined in order to calculate the overall circulation of the Caspian Sea. The outputs and results showed that the approximate mean current created only by rivers was 1/10 of the circulation velocity created by the wind driving force and this was about 1/3 in May and June due to an increase in the discharge of the Volga River. However, the peak velocity of the wind-driven current was much less than that of the currents caused by the river Volga near its entrance. Because the wind forcing also plays an effective role in evaporation over the water surface, and changes the density of water masses, it could be considered a factor that indirectly contributed to the formation of currents as a result of the density gradient. Also the rivers, due to their low salinity and a different temperature, can change the water density creating currents resulted from the density gradient.Our results showed that the mean surface current speed for most of the year, regardless of the wind effect on the formation of currents, caused by density gradients, is caused mainly by the wind stress. Therefore, it could be concluded that the wind-driven forcing near the surface was the main cause of surface current formations of the Caspian Sea. Our results also showed that with all forcing thermohaline circulation in the northern part of the Caspian Sea in cold seasons and deep basin water, circulations during the year were the main components of abyssal flows in the Caspian Sea. The interesting feature of the deep flow was the abyssal flow over the Abshooran sill (between the middle and southern basins of the Caspian Sea) that as it entered the southern basin it generated an isobathic flow in the deeper part of this basin.

The occurrence of nonlinear internal waves in the Gulf of Oman had been proved from recording Synthetic Aperture Radar (SAR) images and processing of their signatures. Most of these internal wave packets were observed in the Gulf of Oman shelf region at the east of Musandam Peninsula. In this study, the formation of nonlinear internal waves from the internal tide has been simulated using three dimensional, non-hydrostatic and fully nonlinear MITgcm model. The model results showed the formation of non-linear internal solitary wave packets at the Gulf of Oman shelf region. The numerical results of this study have been compared with SAR observations and published literatures which showed that the present work at some parameters (e. g. internal wave packet separation and the number of internal solitary waves in the packets) is closer to the radar observations rather than previous published literatures.

Heat budget is one of the most important issues in sea and ocean researches. Heat budget in the sea involves four components: solar radiation, long wave radiation, direct heat transfer between air and water and heat transfer through evaporation. Meteorological parameters and sea surface temperature are the most effective factors on the Heat budget in sea. In this study, meteorological and sea surface temperature data were used for investigating the heat budget of Chabahar and Pozm bays that have economical impotence in southeast of Iran. Results of this study showed that the annual average of isolation, flux of net long wave radiation, latent heat flux and sensible heat flux in Pozm bay were 231.02, -62.48,- 77.74, -6.62 W.m-2, respectively and in Chabahar bay were 234, -56.16, -62.43 and -4.98 W.m-2, respectively. In both bays, isolation and sensible heat flux have the highest and the lowest portion in the heat budget, respectively. Annual Average of net heat flux in Pozm and Chabahar bays were calculated +84.17 and +111.07 W.m-2, respectively. So, in this period, (84.17 and 111.07 W.m-2) energy flux flow out by exchanging water of Pozm and Chabahar bays with Gulf of Oman.

Outflow intrusions are often observed in vertical profiles of temperature and salinity in the ocean (for instance the Red Sea and the Persian Gulf outflow into the open sea). They are made visible by large fluctuations, or inversions, in the profiles and as zig-zag patterns in temperature–salinity plots. These features typically have vertical scales of 10–100 m and horizontal scales of 1–100 km. In this research, first by using the collected data of the salinity and temperature in the region of the Oman sea in spring (1996) season, the sound speed was calculated by Wilson formula, then by plotting the profile of the sound speed, it was seen that the vertical structure at depth 200 to 400 m of the profile have anomaly. Using acoustic sources in presence and absence of outflow intrusion at different depths, the sound propagation was studied by method ray. The simulation have shown that the of outflow intrusion leads to the creation sound channel and absence of the outflow intrusion leads to the vanish sound channel.

The present study covers the results from the CTD observations of the PG-GOOS cruises. CTD profiles were collected in eight cruises at 169 stations, from fall 2012 to the late summer 2013. Spatial and temporal distributions of the temperature, salinity and density were investigated. In summer, water column at deep stations was strongly stratified and at shallow stations water column was moderately well-mixed. The coincidence of surface heating resulted in the strength of summer stratification. Increasing in temperature and particularly salinity near the bottom in southern stations of the Strait of Hormuz indicated trace of the Persian Gulf Water outflow. Strong and weak thermocline layers are formed in summer (Δ􀜶 􀵎 12􀔨) and winter in deep stations (Δ􀜶 􀵎 6􀔨), respectively. T-S diagrams at deep part of the Strait of Hormuz showed two water masses i.e. the Indian Ocean Surface Water (IOSW) inflow to the Persian Gulf and Persian Gulf outflow dense water. The movement of scatter plots along temperature and salinity axes indicated the influence of the seasonal variations of the Indian Ocean Surface Water (IOSW). The results of this project are the most historically magnificent oceanographic survey of the Persian Gulf and Gulf of Oman with wide range of applications.

In this study، SWAN numerical model used to modeling waves and obtain the significant wave height in range of Amirabad seaport of Caspian Sea. To do this، first، a general model to modeling the wave height in the entire Caspian Sea was built. Then the boundary conditions obtained from the general model، by using the NEST operation of SWAN model، modeling the local with higher magnification in the area Amirabad Seaport was used. The local models built in the Amirabad، was calibration and verification with waves profile data recorded by buoys deployed in that area. Comparison the results with data measured by the Amirabad buoy shows that modeling done in this area had a good accuracy. Then running the SWAN model for three years and Obtained significant wave height in the desired location. Finally the wave energy obtained from significant wave height.

In this study, the physicochemical parameters of seawater (inc. depth, temperature, conductivity, salinity, dissolved oxygen, pH, chlorophyll a, turbidity, density and sound velocity) of the coastal waters around the Bushehr Peninsula (28° 42′N to 29° 00′N and 50° 39′E to 50° 57′E) were investigated monthly, during July 2011 to July 2012. A CTD (OCEAN SEVEN 316; IDRONAUT, Italy) measured the mentioned parameters of 12 stations in vertical profiles with time step of one second. Then, the quality control procedures were performed on the measured parameters according to IOC methods. Results showed that the sea temperature experienced an 18°C decline from summer to winter. Most of physicochemical parameters were directly affected by these considerable fluctuations. Water column of the study area was divided to 10 layers from surface to bottom. A weak seasonal thermocline (where temperature decreases to 4°C) was observed between layers 3 to 8 in the stations with a depth of more than 20m in the warmest months of the year. This seasonal thermocline generated a weak picnocline whose gradient was ascendant, just opposite the thermocline trend. During the cold months, water column become well-mixed due to the insignificant differences of surface and bottom temperature (<1°C). Surface salinity of the study area increased from about 37 psu in summer to 41 psu in winter whereas Khark synoptic station showed the highest evaporation in summer. pH and dissolved oxygen (DO) values in the study area were inversely correlated to the water temperature so that with going from warm seasons to cold ones, pH and DO increased with respect to water temperature decrease. The values of pH were increased from 7.7 to 8.2 and for DO were from 2 ppm to 10 ppm.

Designing marine structures including shore or offshore requires information about wave regime. For this purpose، different methods were used including empirical methods and numerical models to simulate the wave characteristics. SWAN (Simulating Waves Nearshore) which has been developed for shallow waters had been used for modeling the waves in Anzali port. Wind data obtained from Europe central middle weather forecasting (ECMWF) on 2003 were used as model input and Bathymetry was obtained from NOAA site. To achieve more accurate results، the model was firstly ran in the whole Caspian Sea and then، in Anzali port. Boundary condition of local model was extracted from Caspian Sea model. Calibration of the model was carried out using measured wave data. For verifying، the results were compared to those obtained from the project ISWM. The results indicate acceptable accuracy compared to buoy measurements. However، the modeled peak period is underestimated. Therefore، a correction factor should be considered for peak period.

From the acoustical oceanography point of view the ocean is a sophisticated environment. Existence of outflow intrusion (for instance, outflow of the Persian Gulf), internal waves, and small-scale turbulence perturb the horizontally stratified character of the sound velocity and cause spatial and temporal fluctuations of the sound propagation. In this experimental study, we have investigated signals fluctuations over time (was powered by a 20 MHz/Arbitrary Waveform Generator Model DG 1022 set to generate a 10 cycle sinusoid burst at frequency of 120 kHz with amplitude of 20 volts peak-to-peak) in a pre-stratification environment outside of the intrusion of turbulent plume. All experiments were carried out in a glass tank 2.19 m long, 1.27 m wide and 0.8 m deep. Before the experiments, four transducers (of which three of them are transmitters and the rest of them as receiver) are mounted opposite to each other with a separation of 1.65 m on two iron bars inside the tank. The distance between each transducer is 0.14 m. These holders are facing each other at a distance 0.3m from the tank wall. Prior to the beginning of the experiments with stratification, the acoustic measurements were executed in fresh water. All received signals were sampled at 5 MHz in all experiments. A fourth-order Butterworth band-pass filter was applied to the received voltage time series, with cutoff frequencies at 110 and 130 kHz for the 120-kHz data. In case where a “filling box" stratification (Baines and Turner, 1969) is used, the tank was initially filled with fresh water to a depth of 0.48 m. The water was then stratified using a plume of dense salt solution falling from the end of small tube (a nozzle of 3 mm diameter) placed at 0.47 m from the base with a buoyancy flux of F=g'×Vo=. After the set-up of the “filling box" stratification in the tank (Fig 1), acoustic signals and hydrophysical data were measured simultaneously. Then to produce the outflow intrusions, a source of dyed salt solution with a density less than the previous case (“filling box") with volume flux of was entered into stratified environment. At the start of the experiment with plume intrusion the speed of the nose of the outflow increased with time. The intrusion is also thickened, and eventually split to generate a new tongue of dyed plume water growing beneath the first layer. The dye tracer in the outflow water was slowly adverted upward to replace water entrained into the plume at shallower depths, and eventually reached to the source level. The outflow intrusion is produced at the start of the experiment at the location of the transmitter in the middle of the tank (at the depth of 0.22 m). The dyed outflow water is wedged-shaped with a sloping interface beneath. In different time intervals the acoustic and hydrophysics data are measured simultaneously, and then these signals in different times, based on the place of the plume outflow, are processed. After investigating the output signals, these results are found: when the transmitter and receiver is positioned into the outflow intrusion (dyed outflow) location, the signal amplitude is decreased at different moments of plume intrusion, but if the transmitter is positioned in the upper and lower part of the outflow intrusion, it causes the signal amplitude to increase (Snell’s law). By applying trace envelope techniques on the received signals, shape of signal change was found with time. Thereby, results indicate that outflow intrusion could be important on acoustical signal fluctuations. Results indicate that outflow intrusion could be important in shapes of the received signals. Also we have observed the occurrence of major signal fluctuations over time is accordance with the sound speed vertical structure changes. It is noticed that this phenomenon is also taken place at the outflow of the Persian of Gulf to the Oman sea. The result of such simulation could be used with attention to the acoustic scale rule, (k is the wave number.) where a lab by thickness of this current at outflow of the Persian Gulf which is about <10 km.

Wave spectrum provides a frequency domain description of the sea surface elevation and the stochastic process. Depending on the nature of the sea state they will be described by different shapes of spectra. Information about the spectral characteristics of waves such as significant wave height, peak wave period and wave spectral energy density are the basic needs of many scientific and engineering activities. In this study the raw wave's data measured by the ADCP in the Asalouye from April 2006 to April 2007 are analyzed. Due to the need to convert the analyzed data into the frequency spectrum through the Fast Fourier Transform, certain considerations are made in analyses. Time series data obtained are classified, and after quality control, these data are used to obtain spectral energy density. The smoothed measured spectrum is compared with some various wave spectra estimated based on theoretical formulations such as Jonswap-Bretschneider-Ochi-Wallop spectra. Results of this study shows that the JONSWAP spectrum is in a good agreement with the measured spectrum. Root mean square values between maximum spectral energy obtained from measured and estimated by JONSWAP is less than other spectral models. It is also found that the spectrum of the region of study is predominant single peak. Furthermore directional wave spectrum is determined by using frequency spectrum based on Longuet – Higgins theory.