A Three-Dimensional Numerical Modelling Study of the Sound Velocity Profiles in the Persian Gulf

Author(s):  
Masoud Sadrinasab ◽  
Karim Kenarkoohi

The Persian Gulf connects to the Indian Ocean via the Strait of Hormuz. In this study, a three-dimensional hydrodynamic model (COHERENS) is employed in a fully prognostic mode to derive sound velocity profiles in the Persian Gulf, an evaporation-driven inverse estuary that is governed by import of surface water from the adjacent ocean and export of saline bottom gulf water through the Strait of Hormuz. During spring and summer, a cyclonic overturning circulation establishes along the full length of the Gulf. During autumn and winter, this circulation breaks up into mesoscale eddies, laterally stirring most of the Gulf’s surface waters. Output of the model shows that sound velocity in the Persian Gulf depends mainly on the temperature in the surface layer whereas the bottom layer as well as the southern part of the Gulf depends on temperature and salinity. Maximum sound velocity occurs during summer in the Persian Gulf which decreases gradually moving from Strait of Hormuz to the north western part of the Gulf. A gradual decrease in sound velocity profiles with depth was commonly observed almost at all stations in the Gulf. However, an exception occurred in Strait of Hormuz during winter. The results of the model are very close to previous observations.

2005 ◽  
Vol 2 (3) ◽  
pp. 129-164 ◽  
Author(s):  
J. Kämpf ◽  
M. Sadrinasab

Abstract. We employ a three-dimensional hydrodynamic model (COHERENS) to study the circulation and water mass properties of the Persian Gulf, which is a large inverse estuary. Our findings suggest that the Persian Gulf experiences a distinct seasonal cycle in which a Gulf-wide cyclonic overturning circulation establishes in spring and summer, but this disintegrates into mesoscale eddies in autumn and winter. Establishment of the Gulf-wide circulation coincides with establishment of thermal stratification and strengthening of the baroclinic exchange circulation through the Strait of Hormuz. The latter is associated with winter cooling of extreme saline (>45 psu) water in shallow regions along the coast of United Arab Emirates. To validate the model results, we present a detailed comparison with observational evidence.


Ocean Science ◽  
2006 ◽  
Vol 2 (1) ◽  
pp. 27-41 ◽  
Author(s):  
J. Kämpf ◽  
M. Sadrinasab

Abstract. We employ a three-dimensional hydrodynamic model (COHERENS) in a fully prognostic mode to study the circulation and water mass properties of the Persian Gulf – a large inverse estuary. Our findings, which are in good agreement with observational evidence, suggest that the Persian Gulf experiences a distinct seasonal cycle in which a gulf-wide cyclonic overturning circulation establishes in spring and summer, but this disintegrates into mesoscale eddies in autumn and winter. Establishment of the gulf-wide circulation coincides with establishment of thermal stratification and strengthening of the baroclinic exchange circulation through the Strait of Hormuz. Winter cooling of extreme saline (>45) water in shallow regions along the coast of United Arab Emirates is a major driver of this baroclinic circulation.


Author(s):  
Smaeyl Hassanzadeh ◽  
Fahimeh Hosseinibalam ◽  
Ali Rezaei-Latifi

AbstractIn this study, the Navier-Stokes equations that embrace conservation equations of momentum, volume, heat and salt are solved by using a 3-D numerical model. Then, based on the values obtained, the structure and variability of the outflow/inflow between the Persian Gulf and the Gulf of Oman is investigated. The basic equations are cast in a bottom-following, sigma coordinate system which greatly simplifies the numerical solution. Conservative finite difference methods are used to discretise the mathematical model in space. The model results, which are in agreement with limited direct measurements in the Strait, show a volume transport of deep outflow and a near-surface outflow from the Persian Gulf to the Gulf of Oman through the southern part of the Strait. About 65% of total outflow occurs in the bottom layer (40 m to the bottom) and 35% in the upper layer (from the surface to 40 m deep) during the year. The annual mean of surface inflow from the Gulf of Oman to the Persian Gulf, which occurs within the northern part of the Strait is about 0.2 Sv. The net volume transport annual mean through the Strait into the Persian Gulf is about 0.03 Sv. Strong temperature and density contrasts between bottom and surface layer waters are established in spring and summer. These are more pronounced in the southern part of the Strait. In the northern part of the Strait, the salinity contrast is nearly constant, but in the southern half it varies significantly during the year.


1963 ◽  
Vol 53 (1-2) ◽  
pp. 43-54 ◽  
Author(s):  
I. A. Richmond

In the most southerly group of desert routes between Syria and Mesopotamia Palmyra lies at the cross-roads. The north-eastward route from Damascus to Circesium is crossed by the eastward route from Emesa, now Homs, to Babylonia. Palmyra owes this key-position first to its precious springs and secondly to the fact that here the natural traffic lines from west to east debouch from the Syrian mountains into the head of the eastwardlooking basin of the Wadi el Khorr, a winter tributary of the Euphrates. Nor were these obvious routes the sole possibility. At Circesium the Euphrates may be crossed: at its eastward turn the lower river and its valley-dwellers become dominant—here runs the modern frontier between Syria and Iraq. Avoiding this control, caravan routes, negotiable solely by those with intimate knowledge of the waste and its people, lead direct to the heart of Mesopotamia and onwards to the Persian Gulf. As between East and West, Palmyra, an island in the desert, offered both a mart for exchange and an essential staging-point for direct through traffic. Its possessors were by nature masters of the situation; and, while they might be subject to the cultural or political influences of either East or West, their geographical isolation secured for them an independence founded upon pre-eminent experience of desert ways, which constituted them the natural masters and middlemen of the caravan routes that met and branched or crossed in their oasis.


Ocean Science ◽  
2016 ◽  
Vol 12 (3) ◽  
pp. 687-701 ◽  
Author(s):  
Pierre L'Hégaret ◽  
Xavier Carton ◽  
Stephanie Louazel ◽  
Guillaume Boutin

Abstract. The Persian Gulf produces high-salinity water (Persian Gulf Water, PGW hereafter), which flows into the Sea of Oman via the Strait of Hormuz. Beyond the Strait of Hormuz, the PGW cascades down the continental slope and spreads in the Sea of Oman under the influence of the energetic mesoscale eddies. The PGW outflow has different thermohaline characteristics and pathways, depending on the season. In spring 2011, the Phys-Indien experiment was carried out in the Arabian Sea and in the Sea of Oman. The Phys-Indien 2011 measurements, as well as satellite observations, are used here to characterize the circulation induced by the eddy field and its impact on the PGW pathway and evolution. During the spring intermonsoon, an anticyclonic eddy is often observed at the mouth of the Sea of Oman. It creates a front between the eastern and western parts of the basin. This structure was observed in 2011 during the Phys-Indien experiment. Two energetic eddies were also present along the southern Omani coast in the Arabian Sea. At their peripheries, ribbons of freshwater and cold water were found due to the stirring created by the eddies. The PGW characteristics are strongly influenced by these eddies. In the western Sea of Oman, in 2011, the PGW was fragmented into filaments and submesoscale eddies. It also recirculated locally, thus creating salty layers with different densities. In the Arabian Sea, a highly saline submesoscale lens was recorded offshore. Its characteristics are analyzed here and possible origins are proposed. The recurrence of such lenses in the Arabian Sea is also briefly examined.


2021 ◽  
Vol 73 (1) ◽  
pp. 169-178
Author(s):  
M. Alipour Amroabadi ◽  
E. Rahimi ◽  
A. Shakerian ◽  
H. Momtaz

ABSTRACT Foodborne viruses including hepatitis A virus (HAV), norovirus (NoV), rotavirus (RoV) and hepatitis E virus (HEV) are easily transmitted through contaminated seafoods. The current research was done to assess the incidence of RoV, NoV GI and GII,hAV and hEV in fish and shrimp samples caught from the Persian Gulf, Iran. Three-hundred and twenty fish and shrimp samples were collected. The presence of foodborne viruses were assessed by the real-time PCR. Forty-nine out of 320 (15.31%) fish and shrimp samples were positive for foodborne viruses. Distribution of hAV, NoV GI and NoV GII amongst all studied samples were 0.93%, 5.93% and 8.43%, respectively. hEV and RoV viruses were not found in studied samples. Parastromateus niger and Scomberomorus commerson fish and Penaeus monodon shrimp were the most frequently contaminated samples. Simultaneous incidence of hAV and NoV GI and hAV and NoV GII were 0.31% and 0.93%, respectively. Distribution of foodborne viruses in samples collected through spring, summer, autumn and winter seasons were 14.28%, 9.33%, 11.76% and 24.44%, respectively. Findings revealed that the incidence of foodborne viruses was significantly associated with seafood species and also season of sampling.


2013 ◽  
Vol 20 (2) ◽  
pp. 231-238 ◽  
Author(s):  
M. R. Saadatinejad ◽  
H. Hassani

Abstract. The Persian Gulf and its surrounding area are some of the biggest basins and have a very important role in producing huge amounts of hydrocarbon, and this potential was evaluated in order to explore the target for geoscientists and petroleum engineers. Wavelet transform is a useful and applicable technique to reveal frequency contents of various signals in different branches of science and especially in petroleum studies. We applied two major capacities of continuous mode of wavelet transform in seismic investigations. These investigations were operated to detect reservoir geological structures and some anomalies related to hydrocarbon to develop and explore new petroleum reservoirs in at least 4 oilfields in the southwest of Iran. It had been observed that continuous wavelet transform results show some discontinuities in the location of faults and are able to display them more clearly than other seismic methods. Moreover, continuous wavelet transform, utilizing Morlet wavelet, displays low-frequency shadows on 4 different iso-frequency vertical sections to identify reservoirs containing gas. By comparing these different figures, the presence of low-frequency shadows under the reservoir could be seen and we can relate these variations from anomalies at different frequencies as an indicator of the presence of hydrocarbons in the target reservoir.


Antiquity ◽  
2016 ◽  
Vol 90 (353) ◽  
Author(s):  
Abbas Moghaddam

The Zohreh Prehistoric Project (ZPP), a long-term archaeological research programme focused on the river valley south of the modern city of Behbahan in Khuzestan Province, was launched in April 2015 (Figure 1). The valley, which lies in close proximity to the northern coast of the Persian Gulf, was surveyed extensively during the early 1970s by Hans Nissen from the Oriental Institute of the University of Chicago (Nissen & Redman 1971; Dittmann 1984, 1986). The ZPP aims to develop full-coverage archaeological survey of the valley, focusing on the human landscape over time, mostly in relation to settlement hierarchy and dynamics, modes of production and the emergence of regional centres at the end of the fifth and beginning of the fourth millennia BC. The focal point for the project is the principal site of the Zohreh Valley, known as Tol-e Chega Sofla (39RN1Q22108; the site was previously registered as Chogha Sofla, BZ.71 (Dittmann 1984: 110). We have changed this to reflect its local name. The digital reference is the unique Iranian archaeology map registration number.


The Holocene ◽  
2016 ◽  
Vol 27 (4) ◽  
pp. 613-620 ◽  
Author(s):  
Frieda Bogemans ◽  
Mathieu Boudin ◽  
Rindert Janssens ◽  
Cecile Baeteman

The early- and mid-Holocene deposits of the Lower Khuzestan plain at the north-eastern margin of the Persian Gulf have been investigated by means of facies analysis of sediment successions of undisturbed cores. Organic material and molluscs have been selected for dating by radiocarbon whereby possible contamination by hard-water effect is discussed. The results suggest that the Holocene transgression in Mesopotamia may have taken place later than generally accepted. Before ca. 7700–7900 yr cal. BP, the plain was characterized by mud-dominated fluvial systems. During the mid-Holocene, tides invaded the existing valleys, and the sedimentary environment shifted from fluvial to estuarine but not as extensively as has previously been suggested. The estuarine environments lasted for about 2000–2500 years until ca. 4850–5000 yr cal. BP when the seaward part of the plain was again characterized by widespread fluvial sedimentation.


Sign in / Sign up

Export Citation Format

Share Document