Journal articles: 'Fronts thermohalins'

1

Shakespeare, Callum J., and Leif N. Thomas. "A New Mechanism for Mode Water Formation Involving Cabbeling and Frontogenetic Strain at Thermohaline Fronts. Part II: Numerical Simulations." Journal of Physical Oceanography 47, no. 7 (July 2017): 1755–73. http://dx.doi.org/10.1175/jpo-d-17-0001.1.

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AbstractSubmesoscale-resolving numerical simulations are used to investigate a mechanism for sustained mode water formation via cabbeling at thermohaline fronts subject to a confluent strain flow. The simulations serve to further elucidate the mechanism and refine the predictions of the analytical model of Thomas and Shakespeare. Unlike other proposed mechanisms involving air–sea fluxes, the cabbeling mechanism, in addition to driving significant mode water formation, uniquely determines the thermohaline properties of the mode water given knowledge of the source water masses on either side of the front. The process of mode water formation in the simulations is as follows: Confluent flow associated with idealized mesoscale eddies forces water horizontally toward the front. The frontogenetic circulation draws this water near adiabatically from the full depth of the thermohaline front up to the surface 25 m, where resolved submesoscale instabilities drive intense mixing across the thermohaline front, creating the mode water. The mode water is denser than the surrounding stratified fluid and sinks to fill its neutral buoyancy layer at depth. This layer gradually expands up to the surface, and eddies composed entirely of this mode water detach from the front and accumulate in the diffluent regions of the domain. The process continues until the source water masses are exhausted. The temperature–salinity (T–S) relation of the resulting mode water is biased to the properties of the source water that has the larger isopycnal T–S anomaly. This mechanism has the potential to drive O(1) Sv (1 Sv ≡ 106 m3 s−1) mode water formation and may be important in determining the properties of mode water in the global oceans.

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Thomas, Leif N., and Callum J. Shakespeare. "A New Mechanism for Mode Water Formation involving Cabbeling and Frontogenetic Strain at Thermohaline Fronts." Journal of Physical Oceanography 45, no. 9 (September 2015): 2444–56. http://dx.doi.org/10.1175/jpo-d-15-0007.1.

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AbstractA simple analytical model is used to elucidate a potential mechanism for steady-state mode water formation at a thermohaline front that involves frontogenesis, submesoscale lateral mixing, and cabbeling. This mechanism is motivated in part by recent observations of an extremely sharp, density-compensated front at the North Wall of the Gulf Stream. Here, the intergyre, along-isopycnal, salinity–temperature difference is compressed into a span of a few kilometers, making the flow susceptible to cabbeling. The sharpness of the front is caused by frontogenetic strain, which is presumably balanced by submesoscale lateral mixing processes. The balance is studied with the simple model, and a scaling is derived for the amount of water mass transformation resulting from the ensuing cabbeling. The transformation scales with the strain rate, equilibrated width of the front, and the square of the isopycnal temperature contrast across the front. At the major ocean fronts where mode waters are found, this isopycnal temperature contrast decreases with increasing density near the isopycnal layers where mode waters reside. This implies that cabbeling should result in a convergent diapycnal mass flux into mode water density classes. The scaling for the transformation suggests that at these fronts the process could generate 0.01–1 Sverdrups (Sv; 1 Sv ≡ 106 m3 s−1) of mode water. These formation rates, while smaller than mode water formation by air–sea fluxes, should be independent of season and thus could fill select isopycnal layers continuously and play an important role in the dynamics of mode waters on interannual time scales.

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Walczowski, W. "Frontal structures in the West Spitsbergen Current margins." Ocean Science Discussions 10, no. 4 (July 2, 2013): 985–1030. http://dx.doi.org/10.5194/osd-10-985-2013.

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Abstract. The structures of the hydrographic fronts separating the Atlantic origin waters from ambient waters in the northern Nordic Seas are discussed. Flows of the western and eastern branches of the West Spitsbergen Current create the Atlantic domain borders and maintain these fronts. The work is based on previous research and on investigations in the project DAMOCLES (Developing Arctic Modeling and Observational Capabilities for Long-term Environmental Studies). Most of the observational data were collected during the R/V Oceania cruises. The main focus of the paper is put on the western border of the Atlantic domain – the Arctic Front, along- and transfrontal transports, the front instability and variability. The baroclinic instability and advection of baroclinic eddies which occurs due to this instability were found as the main transfrontal transport processes. Most of the Atlantic Water transported by the western branch recirculates west and southward. The eastern branch of the West Spitsbergen Current provides most of the Atlantic Water entering the Arctic Ocean. Both processes are very important for the Arctic and global Thermohaline Circulation.

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Klein, Patrice, Anne-Marie Treguier, and Bach Lien Hua. "Three-dimensional stirring of thermohaline fronts." Journal of Marine Research 56, no. 3 (May 1, 1998): 589–612. http://dx.doi.org/10.1357/002224098765213595.

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5

Walczowski, W. "Frontal structures in the West Spitsbergen Current margins." Ocean Science 9, no. 6 (November 14, 2013): 957–75. http://dx.doi.org/10.5194/os-9-957-2013.

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Abstract. The structures of the hydrographic fronts separating the Atlantic-origin waters from ambient waters in the northern Nordic Seas are discussed. Flows of the western and eastern branches of the West Spitsbergen Current create the Atlantic domain borders and maintain these fronts. This work is based on previous research and on investigations carried out in the project DAMOCLES (Developing Arctic Modelling and Observational Capabilities for Long-term Environmental Studies). Most of the observational data were collected during the R/V Oceania cruises. The main focus of the paper is the western border of the Atlantic domain – the Arctic Front, alongfrontal and transfrontal transports, and the front instability and variability. The alongfrontal baroclinic jet streams were described as a significant source of the Atlantic Water and heat in the Nordic Seas. The baroclinic instability and advection of baroclinic eddies which occurs due to this instability were found to be the main transfrontal transport processes. Most of the Atlantic Water transported by the western branch recirculates west and southward. The eastern branch of the West Spitsbergen Current provides most of the Atlantic Water entering the Arctic Ocean. Both processes are very important for the Arctic and global thermohaline circulation.

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Kuzmina, Natalia, Bert Rudels, Tapani Stipa, and Victor Zhurbas. "The Structure and Driving Mechanisms of the Baltic Intrusions." Journal of Physical Oceanography 35, no. 6 (June 1, 2005): 1120–37. http://dx.doi.org/10.1175/jpo2749.1.

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Abstract Data from closely spaced CTD profiling performed in the eastern Gotland Basin after the 1993 inflow event are used to study thermohaline intrusions in the Baltic Sea. Two CTD cross sections display abundant intrusive layers in the permanent halocline. Despite the overwhelming dominance of the salinity stratification, diffusive convection is shown to work in the Baltic halocline enhancing diapycnical mixing. To understand the driving mechanisms of observed intrusions, these are divided into different types depending on their structural features. Only two types of observed intrusions are suggested to be strongly influenced by diffusive convection: 1) relatively thin (3–5 m) and long (up to 8 km) intrusions inherent to high-baroclinicity regions and 2) relatively thick (∼10 m) and short (2–5 km) intrusions inherent to low-baroclinicity regions. To verify this hypothesis the linear stability models of 3D and 2D double-diffusive interleaving in approximation of a finite-width front were used. It is shown that the horizontal and vertical scales of thick and short intrusions correspond well to the 3D rotational mode for a pure thermohaline front. Since mesoscale thermohaline fronts in the Baltic halocline are shown to be essentially baroclinic, the influence of baroclinicity on the rotational mode was studied, which resulted in more adequate estimates of the growth rate of the unstable modes. The thin and long intrusions are shown to be likely driven by 2D baroclinic instability triggered by diffusive convection. The model results demonstrated that diffusion convection can be considered as a possible driver for some intrusions observed in the Baltic halocline, while most of the intrusions have a non-double-diffusive origin. Nevertheless, diffusive convection can affect all types of observed intrusions, for example, by tilting them relative to isopycnals and thereby promoting diapycnal mixing and ventilation in the Baltic halocline.

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KOKKINI, Z., R. GERIN, P. M. POULAIN, E. MAURI, Z. PASARIĆ, I. JANEKOVIĆ, M. PASARIĆ, H. MIHANOVIĆ, and I. VILIBIĆ. "A multiplatform investigation of Istrian Front dynamics (north Adriatic Sea) in winter 2015." Mediterranean Marine Science 18, no. 2 (July 31, 2017): 344. http://dx.doi.org/10.12681/mms.1895.

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In the northeastern Adriatic Sea, southwest of the Istrian Peninsula, a persistent thermohaline front is formed, called here the Istrian Front (IF). A Slocum glider was operated across the IF near the entrance to the Kvarner Bay between 24 and 27 February 2015. Three Acoustic Doppler Current Profilers (ADCPs) were also deployed at the entrance of the Kvarner Bay during the same period. The glider crossed twice the IF, which was characterized by a fast response to the local wind condition, detecting strong salinity, temperature and density gradients. During the first crossing a strong northeasterly Bora wind was blowing. This resulted in a very sharp and strong thermohaline front, extended vertically in the entire water column, between saltier and warmer water to the south, and the fresher and colder water to the north. Across the front the SST changed ~ 1.2 °C within a distance of 2.4 km. On the contrary, during the second crossing, about 2 days later, under weaker wind conditions, the IF appeared to be much smoother, inclined and wider while the SST changed ~ 1.2 °C within a distance of 8 km. A strong density gradient was also reported, coincident with the thermohaline IF. From previous observations, mainly experiments in 2003, the IF was known only as a thermohaline front compensated in density. In winter 2015, the density front was strong and well defined, demonstrating a density difference of about 0.36 kg/m3 within a distance of 2.4 km. The ADCP measurements and the numerical model simulations demonstrated a circulation of cold waters exiting from the Kvarner Bay in the southern part of the entrance, while during a Bora event this outflow was taking place in the northern part.

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Sheehan, Peter M. F., Barbara Berx, Alejandro Gallego, Rob A. Hall, Karen J. Heywood, Sarah L. Hughes, and Bastien Y. Queste. "Shelf sea tidal currents and mixing fronts determined from ocean glider observations." Ocean Science 14, no. 2 (March 15, 2018): 225–36. http://dx.doi.org/10.5194/os-14-225-2018.

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Abstract. Tides and tidal mixing fronts are of fundamental importance to understanding shelf sea dynamics and ecosystems. Ocean gliders enable the observation of fronts and tide-dominated flows at high resolution. We use dive-average currents from a 2-month (12 October–2 December 2013) glider deployment along a zonal hydrographic section in the north-western North Sea to accurately determine M2 and S2 tidal velocities. The results of the glider-based method agree well with tidal velocities measured by current meters and with velocities extracted from the TPXO tide model. The method enhances the utility of gliders as an ocean-observing platform, particularly in regions where tide models are known to be limited. We then use the glider-derived tidal velocities to investigate tidal controls on the location of a front repeatedly observed by the glider. The front moves offshore at a rate of 0.51 km day−1. During the first part of the deployment (from mid-October until mid-November), results of a one-dimensional model suggest that the balance between surface heat fluxes and tidal stirring is the primary control on frontal location: as heat is lost to the atmosphere, full-depth mixing is able to occur in progressively deeper water. In the latter half of the deployment (mid-November to early December), a front controlled solely by heat fluxes and tidal stirring is not predicted to exist, yet a front persists in the observations. We analyse hydrographic observations collected by the glider to attribute the persistence of the front to the boundary between different water masses, in particular to the presence of cold, saline, Atlantic-origin water in the deeper portion of the section. We combine these results to propose that the front is a hybrid front: one controlled in summer by the local balance between heat fluxes and mixing and which in winter exists as the boundary between water masses advected to the north-western North Sea from diverse source regions. The glider observations capture the period when the front makes the transition from its summertime to wintertime state. Fronts in other shelf sea regions with oceanic influence may exhibit similar behaviour, with controlling processes and locations changing over an annual cycle. These results have implications for the thermohaline circulation of shelf seas.

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9

Morin, P., P. Le Corre, and J. Le Févre. "Assimilation Aand Regeneration of Nutrients off the West Coast of Brittany." Journal of the Marine Biological Association of the United Kingdom 65, no. 3 (August 1985): 677–95. http://dx.doi.org/10.1017/s0025315400052528.

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A high degree of variation in hydrographic conditions is found in the so-called Iroise Sea, within less than 100 km of the west coast of Brittany. Tidal current maximal velocity, especially, ranges there from about 0·5 knot to more than 8 knots (locally, near the island of Ushant), i.e. practically as wide a range as found over the whole of north-west European shelf seas. Pelagic ecosystems accordingly exhibit a high degree of variety, related not only to classical inshore-offshore gradients, but also to the extent of vertical mixing or stratification. Areas where different physical and biological conditions prevail are generally separated by rather clearcut boundaries. The better-known of these is the Ushant thermal front, which runs in summer across the whole entrance to the English Channel, but also extends into the Iroise. In addition, freshwater runoff results in thermohaline stratification, or at least in the existence of thermohaline vertical gradients, in the two major bays of the west coast of Brittany. The relevant area is limited seawards by a thermohaline front, the Iroise inner front (Grail & Le Fèvre, 1967; Le Fèvre & Grall, 1970), beyond which are found the well-mixed waters inshore of the Ushant front. Fig. 1 sums up these hydrographic patterns in the area taken here into consideration.

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10

Wang, Jiahao, Kefeng Mao, Xi Chen, and Kelan Zhu. "Evolution and Structure of the Kuroshio Extension Front in Spring 2019." Journal of Marine Science and Engineering 8, no. 7 (July 8, 2020): 502. http://dx.doi.org/10.3390/jmse8070502.

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Satellite data products and high-resolution in situ observations were combined to investigate the evolution and structure of the Kuroshio Extension Front in Spring 2019. The former reveals the variation of the front is influenced by the northward movement of the Kuroshio Extension through transporting warm and saline water to a cold and brackish water region. The latter indicates steep upward slopes of the isopycnals, tilting northward in the frontal zone, as well as several ~300 m thick blobs of North Pacific Intermediate Water between 26.25 and 26.75 kg/m3, where conspicuous thermohaline intrusions occur. Further analysis indicates these thermohaline intrusions prefer to alternate salt fingering and diffusive convection interfaces, and are affected by strong shears.

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Jullion, Loic, Karen J. Heywood, Alberto C. Naveira Garabato, and David P. Stevens. "Circulation and Water Mass Modification in the Brazil–Malvinas Confluence." Journal of Physical Oceanography 40, no. 5 (May 1, 2010): 845–64. http://dx.doi.org/10.1175/2009jpo4174.1.

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Abstract The confluence between the Brazil Current and the Malvinas Current [the Brazil–Malvinas Confluence (BMC)] in the Argentine Basin is characterized by a complicated thermohaline structure favoring the exchanges of mass, heat, and salt between the subtropical gyre and the Antarctic Circumpolar Current (ACC). Analysis of thermohaline properties of hydrographic sections in the BMC reveals strong interactions between the ACC and subtropical fronts. In the Subantarctic Front, Subantarctic Mode Water (SAMW), Antarctic Intermediate Water (AAIW), and Circumpolar Deep Water (CDW) warm (become saltier) by 0.4° (0.08), 0.3° (0.02), and 0.6°C (0.1), respectively. In the subtropical gyre, AAIW and North Atlantic Deep Water have cooled (freshened) by 0.4° (0.07) and 0.7°C (0.11), respectively. To quantify those ACC–subtropical gyre interactions, a box inverse model surrounding the confluence is built. The model diagnoses a subduction of 16 ± 4 Sv (1 Sv ≡ 106 m3 s−1) of newly formed SAMW and AAIW under the subtropical gyre corresponding to about half of the total subduction rate of the South Atlantic found in previous studies. Cross-frontal heat (0.06 PW) and salt (2.4 × 1012 kg s−1) gains by the ACC in the BMC contribute to the meridional poleward heat and salt fluxes across the ACC. These estimates correspond to perhaps half of the total cross-ACC poleward heat flux. The authors’ results highlight the BMC as a key region in the subtropical–ACC exchanges.

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Oka, Eitarou, and Toshio Suga. "Differential Formation and Circulation of North Pacific Central Mode Water." Journal of Physical Oceanography 35, no. 11 (November 1, 2005): 1997–2011. http://dx.doi.org/10.1175/jpo2811.1.

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Abstract A repeat hydrographic section along 165°E was analyzed to verify a westward extension of the formation region of the North Pacific Ocean Central Mode Water (CMW) suggested by previous synoptic observations, and to investigate the relation between the formation region and thermohaline fronts. The CMW formation region extends at least as far west as 155°E, much farther than recognized in a previous study based on climatology. It is located in two interfrontal regions between the Kuroshio Extension front and the Kuroshio Bifurcation front (KBF), and between the KBF and the subarctic front, where two types of CMW—namely, the lighter variety with potential density of 25.8–26.2 kg m−3 and the denser one of 26.3–26.4 kg m−3—are formed. How this differential formation of CMW is reflected in its gyrewide distribution was examined using one-time sections of the World Ocean Circulation Experiment (WOCE) Hydrographic Program in the North Pacific. The main circulation paths of the two types of CMW diverge east of the date line; the lighter variety is located in the inner part of the eastern subtropical gyre, and the denser variety is located in the outer part. These results demonstrate that the frontal structure around the northern boundary of the subtropical gyre, particularly the existence of KBF, is essential in determining the properties and the gyrewide distribution of CMW.

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Pauthenet, Etienne, Fabien Roquet, Gurvan Madec, and David Nerini. "A Linear Decomposition of the Southern Ocean Thermohaline Structure." Journal of Physical Oceanography 47, no. 1 (January 2017): 29–47. http://dx.doi.org/10.1175/jpo-d-16-0083.1.

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AbstractThe thermohaline structure of the Southern Ocean is deeply influenced by the presence of the Antarctic Circumpolar Current (ACC), where water masses of the World Ocean are advected, transformed, and redistributed to the other basins. It remains a challenge to describe and visualize the complex 3D pattern of this circulation and its associated tracer distribution. Here, a simple framework is presented to analyze the Southern Ocean thermohaline structure. A functional principal component analysis (PCA) is applied to temperature θ and salinity S profiles to determine the main spatial patterns of their variations. Using the Southern Ocean State Estimate (SOSE), this study determines the vertical modes describing the Southern Ocean thermohaline structure between 5 and 2000 m. The first two modes explain 92% of the combined θ–S variance, thus providing a surprisingly good approximation of the thermohaline properties in the Southern Ocean. The first mode (72% of total variance) accurately describes the north–south property gradients. The second mode (20%) mostly describes salinity at 500 m in the region of Antarctic Intermediate Water formation. These two modes present circumpolar patterns that can be closely related with standard frontal definitions. By projecting any given hydrographic profile onto the SOSE-based modes, it is possible to determine its position relative to the fronts. The projection is successfully applied on the hydrographic profiles of the WOCE SR3 section. The Southern Ocean thermohaline decomposition provides an objective way to define water mass boundaries and their spatial variability and has useful application for comparing model output with observations.

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Severov, Dmitri Nikolaevich, Valentina Pshennikov, and Alexsandr Vasilievich Remeslo. "Fronts and thermohaline structure of the Brazil–Malvinas Confluence System." Advances in Space Research 49, no. 9 (May 2012): 1373–87. http://dx.doi.org/10.1016/j.asr.2012.01.024.

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15

Flexas, Mar M., Martina I. Troesch, Steve Chien, Andrew F. Thompson, Selina Chu, Andrew Branch, John D. Farrara, and Yi Chao. "Autonomous Sampling of Ocean Submesoscale Fronts with Ocean Gliders and Numerical Model Forecasting." Journal of Atmospheric and Oceanic Technology 35, no. 3 (March 2018): 503–21. http://dx.doi.org/10.1175/jtech-d-17-0037.1.

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ABSTRACTSubmesoscale fronts arising from mesoscale stirring are ubiquitous in the ocean and have a strong impact on upper-ocean dynamics. This work presents a method for optimizing the sampling of ocean fronts with autonomous vehicles at meso- and submesoscales, based on a combination of numerical forecast and autonomous planning. This method uses a 48-h forecast from a real-time high-resolution data-assimilative primitive equation ocean model, feature detection techniques, and a planner that controls the observing platform. The method is tested in Monterey Bay, off the coast of California, during a 9-day experiment focused on sampling subsurface thermohaline-compensated structures using a Seaglider as the ocean observing platform. Based on model estimations, the sampling “gain,” defined as the magnitude of isopycnal tracer variability sampled, is 50% larger in the feature-chasing case with respect to a non-feature-tracking scenario. The ability of the model to reproduce, in space and time, thermohaline submesoscale features is evaluated by quantitatively comparing the model and glider results. The model reproduces the vertical (~50–200 m thick) and lateral (~5–20 km) scales of subsurface subducting fronts and near-bottom features observed in the glider data. The differences between model and glider data are, in part, attributed to the selected glider optimal interpolation parameters and to uncertainties in the forecasting of the location of the structures. This method can be exported to any place in the ocean where high-resolution data-assimilative model output is available, and it allows for the incorporation of multiple observing platforms.

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Shcherbina, Andrey Y., Michael C. Gregg, Matthew H. Alford, and Ramsey R. Harcourt. "Characterizing Thermohaline Intrusions in the North Pacific Subtropical Frontal Zone." Journal of Physical Oceanography 39, no. 11 (November 1, 2009): 2735–56. http://dx.doi.org/10.1175/2009jpo4190.1.

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Abstract A monthlong field survey in July 2007, focused on the North Pacific subtropical frontal zone (STFZ) near 30°N, 158°W, combined towed depth-cycling conductivity–temperature–depth (CTD) profiling with shipboard current observations. Measurements were used to investigate the distribution and structure of thermohaline intrusions. The study revealed that local extrema of vertical salinity profiles, often used as intrusion indicators, were only a subset of a wider class of distortions in thermohaline fields due to interleaving processes. A new method to investigate interleaving based on diapycnal spiciness curvature was used to describe an expanded class of laterally coherent intrusions. STFZ intrusions were characterized by their overall statistics and by a number of case studies. Thermohaline interleaving was particularly intense within 5 km of two partially compensated fronts, where intrusions with both positive and negative salinity anomalies were widespread. The vertical and cross-frontal scales of the intrusions were on the order of 10 m and 5 km, respectively. Though highly variable, the slopes of these features were typically intermediate between those of isopycnals and isohalines. Although the influence of double-diffusive processes sometime during the evolution of intrusions could not be excluded, the broad spectrum of the observed features suggests that any role of double diffusion was secondary.

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Smyth, William D., and Barry Ruddick. "Effects of Ambient Turbulence on Interleaving at a Baroclinic Front." Journal of Physical Oceanography 40, no. 4 (April 1, 2010): 685–712. http://dx.doi.org/10.1175/2009jpo4297.1.

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Abstract In this paper the authors investigate the action of ambient turbulence on thermohaline interleaving using both theory and numerical calculations in combination with observations from Meddy Sharon and the Faroe Front. The highly simplified models of ambient turbulence used previously are improved upon by allowing turbulent diffusivities of momentum, heat, and salt to depend on background gradients and to evolve as the instability grows. Previous studies have shown that ambient turbulence, at typical ocean levels, can quench the thermohaline interleaving instability on baroclinic fronts. These findings conflict with the observation that interleaving is common in baroclinic frontal zones despite ambient turbulence. Another challenge to the existing theory comes from numerical experiments showing that the Schmidt number for sheared salt fingers is much smaller than previously assumed. Use of the revised value in an interleaving calculation results in interleaving layers that are both weaker and thinner than those observed. This study aims to resolve those paradoxes. The authors show that, when turbulence has a Prandtl number greater than unity, turbulent momentum fluxes can compensate for the reduced Schmidt number of salt fingering. Thus, ambient turbulence determines the vertical scale of interleaving. In typical oceanic interleaving structures, the observed property gradients are insufficient to predict interleaving growth at an observable level, even when improved turbulence models are used. The deficiency is small, though: gradients sharper by a few tens of percent are sufficient to support instability. The authors suggest that this is due to the efficiency of interleaving in erasing those property gradients. A new class of mechanisms for interleaving, driven by flow-dependent fluctuations in turbulent diffusivities, is identified. The underlying mechanism is similar to the well-known Phillips layering instability; however, because of Coriolis effects, it has a well-defined vertical scale and also a tilt angle opposite to that of finger-driven interleaving.

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Bonatti, José Paulo, and Vadlamudi Brahmananda Rao. "Meso-scale perturbations and thermohaline fronts in the south atlantic ocean." Dynamics of Atmospheres and Oceans 30, no. 1 (August 1999): 1–24. http://dx.doi.org/10.1016/s0377-0265(99)00016-0.

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Woods, J. D., R. Onken, and J. Fischer. "Thermohaline intrusions created isopycnically at oceanic fronts are inclined to isopycnals." Nature 322, no. 6078 (July 1986): 446–49. http://dx.doi.org/10.1038/322446a0.

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20

Yanagi, Tetsuo, and Takashi Koike. "Seasonal variation in thermohaline and tidal fronts, Seto Inland Sea, Japan." Continental Shelf Research 7, no. 2 (February 1987): 149–60. http://dx.doi.org/10.1016/0278-4343(87)90076-8.

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21

Flament, Pierre, and Laurence Armi. "The Shear, Convergence, and Thermohaline Structure of a Front*." Journal of Physical Oceanography 30, no. 1 (January 2000): 51–66. http://dx.doi.org/10.1175/1520-0485(2000)030<0051:tscats>2.0.co;2.

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Simeonov, Julian, and Melvin Stern. "Double-Diffusive Intrusions on a Finite-Width Thermohaline Front." Journal of Physical Oceanography 34, no. 7 (July 2004): 1723–40. http://dx.doi.org/10.1175/1520-0485(2004)034<1723:dioaft>2.0.co;2.

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Wang, Dong-Ping, and Antoni Jordi. "Surface frontogenesis and thermohaline intrusion in a shelfbreak front." Ocean Modelling 38, no. 1-2 (January 2011): 161–70. http://dx.doi.org/10.1016/j.ocemod.2011.02.012.

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Fer, Ilker, Keith Makinson, and Keith W. Nicholls. "Observations of Thermohaline Convection adjacent to Brunt Ice Shelf." Journal of Physical Oceanography 42, no. 3 (March 1, 2012): 502–8. http://dx.doi.org/10.1175/jpo-d-11-0211.1.

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Abstract Observations were made of ocean microstructure and horizontal currents adjacent to Brunt Ice Shelf in the southeastern Weddell Sea. Periods of in situ supercooled water extending as deep as 65 m were associated with ice nucleation and frazil formation at depth. Ascending ice crystals due to convection lead to increased dissipation rates. The main outflow of potentially supercooled water from deep beneath ice shelf is suggested to be in the deep channel northeast of the measurement site. Because this water is advected southward along the front, it becomes in situ supercooled, leading to suspended ice formation, thermohaline convection, and enhanced dissipation.

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FLEURY, LAURENCE, and OLIVIER THUAL. "Stationary fronts of the thermohaline circulation in the low-aspect-ratio limit." Journal of Fluid Mechanics 349 (October 25, 1997): 117–47. http://dx.doi.org/10.1017/s0022112097006678.

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A two-dimensional Boussinesq model of the thermohaline convection in a rectangular domain is forced at the top by a prescribed temperature and a prescribed salinity flux. The two forcings have opposite effects on the density field, which leads to the formation of fronts and multiple equilibria. Numerical results are interpreted through a comparison with the solutions of an asymptotic equation, derived in the limit of a shallow basin by Cessi & Young (1992). In order to explain the discrepancies between the numerical and the asymptotic solutions, we extend this asymptotic approach through a geometrical representation and a topological classification of the surface forcings. By comparing three forcings, we propose a global picture which gives clues to interpret the numerical solutions.

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Yanagi, T., A. Isobe, T. Saino, and T. Ishimaru. "Thermohaline front at the mouth of Tokyo Bay in winter." Continental Shelf Research 9, no. 1 (January 1989): 77–91. http://dx.doi.org/10.1016/0278-4343(89)90084-8.

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Shcherbina, A. Y., M. C. Gregg, M. H. Alford, and R. R. Harcourt. "Three-Dimensional Structure and Temporal Evolution of Submesoscale Thermohaline Intrusions in the North Pacific Subtropical Frontal Zone." Journal of Physical Oceanography 40, no. 8 (August 1, 2010): 1669–89. http://dx.doi.org/10.1175/2010jpo4373.1.

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Abstract Four instances of persistent intrusive deformation of the North Pacific Subtropical Front were tagged individually by a Lagrangian float and tracked for several days. Each feature was mapped in three dimensions using repeat towed observations referenced to the float. Isohaline surface deformations in the frontal zone included sheetlike folds elongated in the alongfront direction and narrow tongues extending across the front. All deformations appeared as protrusions of relatively cold, and fresh, water across the front. No corresponding features of the opposite sign or isolated lenslike structures were observed. The sheets were O(10 m) thick, protruded about 10 km into the warm saline side of the front, and were coherent for 10–30 km along the front. Having about the same thickness and cross-frontal extent as the sheets, tongues extended less than 5 km along the front. All of the intrusions persisted as long as they were followed, several days to one week. Their structures evolved on both inertial (23 h) and subinertial (∼10 days) time scales in response to differential lateral advection. The water mass surrounding the intrusions participated in gradual anticyclonic rotation as a part of a mesoscale meander of the subtropical front. The intrusions may be interpreted as a manifestation of three-dimensional submesoscale turbulence of the frontal zone, driven by the mesoscale. Absence of large features of the opposite sign may be indicative of the asymmetry of the underlying dynamics.

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Yanagi, Tetsuo, and Masamitu Shinohara. "Variation in the Thermohaline Front at the Mouth of Ise Bay." Oceanography in Japan 6, no. 5 (1997): 293–97. http://dx.doi.org/10.5928/kaiyou.6.293.

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29

Holbrook, W. S. "Thermohaline Fine Structure in an Oceanographic Front from Seismic Reflection Profiling." Science 301, no. 5634 (August 8, 2003): 821–24. http://dx.doi.org/10.1126/science.1085116.

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30

Yanagi, Tetsuo, and Tetsuro Sanuki. "Variation in the thermohaline front at the mouth of Tokyo Bay." Journal of the Oceanographical Society of Japan 47, no. 4 (August 1991): 105–10. http://dx.doi.org/10.1007/bf02301060.

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31

Kuzmina, Natalia. "Generation of large-scale intrusions at baroclinic fronts: an analytical consideration with a reference to the Arctic Ocean." Ocean Science 12, no. 6 (December 2, 2016): 1269–77. http://dx.doi.org/10.5194/os-12-1269-2016.

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Abstract. Analytical solutions are found for the problem of instability of a weak geostrophic flow with linear velocity shear accounting for vertical diffusion of buoyancy. The analysis is based on the potential-vorticity equation in a long-wave approximation when the horizontal scale of disturbances is considered much larger than the local baroclinic Rossby radius. It is hypothesized that the solutions found can be applied to describe stable and unstable disturbances of the planetary scale with respect, in particular, to the Arctic Ocean, where weak baroclinic fronts with typical temporal variability periods on the order of several years or more have been observed and the β effect is negligible. Stable (decaying with time) solutions describe disturbances that, in contrast to the Rossby waves, can propagate to both the west and east, depending on the sign of the linear shear of geostrophic velocity. The unstable (growing with time) solutions are applied to explain the formation of large-scale intrusions at baroclinic fronts under the stable–stable thermohaline stratification observed in the upper layer of the Polar Deep Water in the Eurasian Basin. The suggested mechanism of formation of intrusions can be considered a possible alternative to the mechanism of interleaving at the baroclinic fronts due to the differential mixing.

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32

Denis, M., M. Thyssen, V. Martin, B. Manca, and F. Vidussi. "Ultraphytoplankton basin-scale distribution in the eastern Mediterranean Sea in winter: link to hydrodynamism and nutrients." Biogeosciences 7, no. 7 (July 20, 2010): 2227–44. http://dx.doi.org/10.5194/bg-7-2227-2010.

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Abstract. The basin-scale distribution of ultraphytoplankton (<10 μm) was determined in the upper 200 m of the eastern Mediterranean Sea during the winter season. Four clusters were resolved by flow cytometry on the basis of their optical properties and identified as Synechococcus, Prochlorococcus, pico- (<3 μm) and nanoeukaryotes (3–10 μm). Synechococcus was the most abundant population (maximum abundance of about 37 000 cells cm−3) and contributed up to 67.7% to the overall ultraphytoplanktonic carbon biomass, whereas the contribution of Prochlorococcus never exceeded 6.5%. The maximum integrated carbon biomass was 1763, 453, 58 and 571 mg C m−2 for nanoeukaryotes, picoeukaryotes, Prochlorococcus and Synechococcus respectively. Water mass properties were analyzed on the basis of temperature and salinity distributions in order to account for the general circulation and locate the main hydrodynamic structures (fronts, gyres, transition between western and eastern basins). The effect of the main hydrodynamic structures and nutrients on the ultraphytoplankton distribution was investigated. No positive correlation between nutrients and phytoplankton could be established when considering large scales. However, below 50 m depth, nutrient ratios between particular stations were correlated to corresponding density ratios. In contrast, significant relationships were found between Synechococcus abundance and density, resulting from the impact of a gyre in southern Adriatic basin and a thermohaline front in the Ionian basin. A significant relationship was also found between picoeukaryotes and salinity in the comparison of western and eastern Mediterranean Sea.

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Hosegood, P. J., M. C. Gregg, and M. H. Alford. "Restratification of the Surface Mixed Layer with Submesoscale Lateral Density Gradients: Diagnosing the Importance of the Horizontal Dimension." Journal of Physical Oceanography 38, no. 11 (November 1, 2008): 2438–60. http://dx.doi.org/10.1175/2008jpo3843.1.

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Abstract A depth-cycling towed conductivity–temperature–depth (CTD) and vessel-mounted acoustic Doppler current profiler (ADCP) were used to obtain four-dimensional measurements of the restratification of the surface mixed layer (SML) at a submesoscale lateral density gradient near the subtropical front. With the objective of studying the role of horizontal processes in restratification, the thermohaline and velocity fields were monitored for 33 h by 16 small-scale (≤15 km2) surveys centered on a drogued float. Daytime warming by insolation caused a unidirectional displacement of the initially vertical isopycnals toward increasing density. Across the entire SML (50-m vertical scale), solar insolation accounted for 60% of observed restratification, but over 10-m scales, the percentage decreased with depth from 80% at 25–35 m to ≤25% at 55–65 m. Below 35 m, stratification was enhanced by the vertically sheared horizontal advection of the lateral density gradient due to a near-inertial wave of ∼100-m vertical wavelength that rotated anticyclonically at the inertial frequency. The phase and similar period (25.4 h) of the local inertial period to the diurnal cycle ensured constructive interference with isopycnal displacements due to insolation. Restratification by sheared advection matched that predicted due to vertically sheared inertial oscillations generated during the geostrophic adjustment of a density front, but direct wind forcing may also have generated the wave that was subsequently modified by interaction with mesoscale vorticity associated with a nearby large-scale front. By further including the effects of lateral uncompensated thermohaline inhomogeneity, the authors can account for 100% ± 20% of the observed N 2 during daytime restratification. No detectable restratification due to the slumping of horizontal density gradients under gravity alone was found.

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Mueller, Rachael D., William D. Smyth, and Barry Ruddick. "Shear and Convective Turbulence in a Model of Thermohaline Intrusions." Journal of Physical Oceanography 37, no. 10 (October 1, 2007): 2534–49. http://dx.doi.org/10.1175/jpo3137.1.

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Abstract Thermohaline interleaving is an important mechanism for laterally fluxing salt, heat, and nutrients between water masses. Interleaving is driven by a release of potential energy resulting from the differing diffusivities of heat and salt in seawater. The flows are composed of stacked intrusions that flux more and less buoyant water in opposite directions. In this paper, the role of shear instability caused by this juxtaposed motion is investigated. The model described in Walsh and Ruddick is modified to include both the effects of shear-induced turbulence and an improved convective mixing parameterization. Shear and convective mixing play a similar and significant role in interleaving dynamics. In the absence of either instability, cross-front fluxes are increased by approximately 30%. While in situ observations of horizontal diffusivity resulting from interleaving are not yet precise enough to calibrate the parameterizations independently, parameter values based on independent laboratory and numerical studies lead to diffusivity predictions that are within the error of the observations.

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35

NITTIS, K., and L. PERIVOLIOTIS. "Circulation and hydrological characteristics of the North Aegean Sea: a contribution from real-time buoy measurements." Mediterranean Marine Science 3, no. 1 (June 1, 2002): 21. http://dx.doi.org/10.12681/mms.255.

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In the framework of the POSEIDON Project, a network of open sea oceanographic buoys equipped with meteorological and oceanographic sensors has been operational in the Aegean Sea since 1998. The analysis of upper-ocean physical data (currents at 3m, temperature and salinity at 3-40m depths) collected during the last 2 years from the stations of the North Aegean basin indicates a strong temporal variability of flow field and hydrological characteristics in both synoptic and seasonal time scales. The northern part of the basin is mainly influenced by the Black Sea Water outflow and the mesoscale variability of the corresponding thermohaline fronts, while the southern stations are influenced by the general circulation of the Aegean Sea with strong modulations caused by the seasonally varying atmospheric forcing.

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36

Fenty, Ian, and Patrick Heimbach. "Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea." Journal of Physical Oceanography 43, no. 5 (May 1, 2013): 863–83. http://dx.doi.org/10.1175/jpo-d-12-064.1.

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Abstract This study investigates the hydrographic processes involved in setting the maximum wintertime sea ice (SI) extent in the Labrador Sea and Baffin Bay. The analysis is based on an ocean and sea ice state estimate covering the summer-to-summer 1996/97 annual cycle. The estimate is a synthesis of in situ and satellite hydrographic and ice data with a regional coupled ⅓° ocean–sea ice model. SI advective processes are first demonstrated to be required to reproduce the observed ice extent. With advection, the marginal ice zone (MIZ) location stabilizes where ice melt balances ice mass convergence, a quasi-equilibrium condition achieved via the convergence of warm subtropical-origin subsurface waters into the mixed layer seaward of the MIZ. An analysis of ocean surface buoyancy fluxes reveals a critical role of low-salinity upper ocean (100 m) anomalies for the advancement of SI seaward of the Arctic Water–Irminger Water Thermohaline Front. Anomalous low-salinity waters slow the rate of buoyancy loss–driven mixed layer deepening, shielding an advancing SI pack from the warm subsurface waters, and are conducive to a positive surface meltwater stabilization enhancement (MESEM) feedback driven by SI meltwater release. The low-salinity upper-ocean hydrographic conditions in which the MESEM efficiently operates are termed sea ice–preconditioned waters (SIPW). The SI extent seaward of the Thermohaline Front is shown to closely correspond to the distribution of SIPW. The analysis of two additional state estimates (1992/93, 2003/04) suggests that interannual hydrographic variability provides a first-order explanation for SI maximum extent anomalies in the region.

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Nagai, Takeyoshi, Amit Tandon, Hidekatsu Yamazaki, Mark J. Doubell, and Scott Gallager. "Direct observations of microscale turbulence and thermohaline structure in the Kuroshio Front." Journal of Geophysical Research: Oceans 117, no. C8 (August 2012): n/a. http://dx.doi.org/10.1029/2011jc007228.

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38

Hareesh Kumar, Panangattu Viswanathan, Basil Mathew, Madathiparambil Ranganatha Ramesh Kumar, Akula Raghunadha Rao, Puvvala Surya Venkata Jagadeesh, Kalarickal Gopalan Radhakrishnan, and Thiyyadi Nandakumar Shyni. "‘Thermohaline front’ off the east coast of India and its generating mechanism." Ocean Dynamics 63, no. 11-12 (September 27, 2013): 1175–80. http://dx.doi.org/10.1007/s10236-013-0652-y.

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39

Capet, Xavier, Philippe Estrade, Eric Machu, Siny Ndoye, Jacques Grelet, Alban Lazar, Louis Marié, Denis Dausse, and Patrice Brehmer. "On the Dynamics of the Southern Senegal Upwelling Center: Observed Variability from Synoptic to Superinertial Scales." Journal of Physical Oceanography 47, no. 1 (January 2017): 155–80. http://dx.doi.org/10.1175/jpo-d-15-0247.1.

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AbstractUpwelling off southern Senegal and Gambia takes place over a wide shelf with a large area where depths are shallower than 20 m. This results in typical upwelling patterns that are distinct (e.g., more persistent in time and aligned alongshore) from those of other better known systems, including Oregon and Peru where inner shelves are comparatively narrow. Synoptic to superinertial variability of this upwelling center is captured through a 4-week intensive field campaign, representing the most comprehensive measurements of this region to date. The influence of mesoscale activity extends across the shelf break and far over the shelf where it impacts the midshelf upwelling (e.g., strength of the upwelling front and circulation), possibly in concert with wind fluctuations. Internal tides and solitary waves of large amplitude are ubiquitous over the shelf. The observations suggest that these and possibly other sources of mixing play a major role in the overall system dynamics through their impact upon the general shelf thermohaline structure, in particular in the vicinity of the upwelling zone. Systematic alongshore variability in thermohaline properties highlights important limitations of the 2D idealization framework that is frequently used in coastal upwelling studies.

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40

Ainley, David G., Stanley S. Jacobs, Christine A. Ribic, and Ian Gaffney. "Seabird distribution and oceanic features of the Amundsen and southern Bellingshausen seas." Antarctic Science 10, no. 2 (June 1998): 111–23. http://dx.doi.org/10.1017/s0954102098000169.

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We describe the distribution and estimate the abundance of seabirds in the Amundsen and southern Bellingshausen seas, and attempt to identify the mesoscale and larger ocean and ice features that explain the birds' discontinuous occurrence patterns. Our general objective was to assess if ocean fronts, especially near the continental shelf break, enhance feeding opportunities for top trophic-level predators. A variety of subsurface thermohaline fronts occurred on both sides of the shelf break, at shallower depths from west to east, and with warmer and saltier water on their northern sides. Pack ice overlaid some of these fronts, especially in the Amundsen Sea. Seabirds comprised either an ice group in pack ice or in polynyas, or an open-water group in waters north of the pack. In the Amundsen Sea, bird densities were near 0 birds km−2 in waters overlying the continental shelf, an unexplained pattern found previously in the Ross Sea but not repeated in the Bellingshausen Sea (5 birds km−2 over the shelf). Both groups were more abundant (densities 3–9 birds km−2) near the frontal zones, the ice edge and the shelf break. In the Amundsen Sea, the distribution of ice-group species was related statistically to proximity of fronts and the pack-ice edge, thermocline slope, and depth of the chlorophyll maximum; water-group distribution was related to distance to the fronts and sea-surface temperature. In the Bellingshausen Sea, distribution of both groups was related to distance to the fronts. Many thousands of petrels, found roosting during daylight on icebergs situated near the shelf break, escaped standard census techniques and, thus, are likely to have diluted positive correlations of avian occurrence patterns with physical features of the environment. While the emperor penguin was seen in high numbers and can dive deep enough to forage within the subsurface fronts, those ocean and food-web processes that apparently affect increased food availability for surface and shallow-diving foragers in the frontal regions remain unclear.

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41

Denis, M., M. Thyssen, V. Martin, B. Manca, and F. Vidussi. "Ultraphytoplankton distribution and upper ocean dynamics in the eastern Mediterranean during winter." Biogeosciences Discussions 6, no. 4 (July 13, 2009): 6839–87. http://dx.doi.org/10.5194/bgd-6-6839-2009.

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Abstract. The vertical distribution of ultraphytoplankton (<10 μm) was determined in the upper 200 m of the eastern Mediterranean during the winter season. Four clusters were resolved by flow cytometry on the basis of their optical properties and identified as Synechococcus, Prochlorococcus, pico- (<3 μm) and nanoeukaryotes (3–10 μm). Synechococcus was the most abundant population (maximum abundance of about 37 000 cells cm−3) and contributed up to 67.7% to the overall ultraphytoplanktonic carbon biomass, whereas the contribution of Prochlorococcus never exceeded 6.5%. The maximum integrated carbon biomass was 1763, 453, 58 and 571 mg C m−2 for nanoeukaryotes, picoeukaryotes, Prochlorococcus and Synechococcus, respectively. Water mass properties were analyzed on the basis of temperature and salinity distributions in order to account for the general circulation and locate the main hydrodynamic structures (fronts, gyres, transition between western and eastern basins). Relationships were established between the ultraphytoplankton distribution and the hydrological characteristics of the main hydrodynamic structures. Significant relationships were found between Synechococcus abundance and density, resulting from the impact of a gyre in southern Adriatic and a thermohaline front in the Ionian Sea. A significant relationship was also found between picoeukaryotes and salinity in the comparison of western and eastern Mediterranean. Relationships were only significant for the most abundant clusters. As the first investigation of ultraphytoplankton winter distribution in the eastern Mediterranean, the present study will significantly contribute to a better knowledge of the ultraphytoplankton structure over seasons and of its dependence on hydrological features.

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42

Roden, Gunnar I. "Thermohaline fronts and baroclinic flow in the Argentine basin during the austral spring of 1984." Journal of Geophysical Research 91, no. C4 (1986): 5075. http://dx.doi.org/10.1029/jc091ic04p05075.

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43

Jiménez, M. P., R. F. Sánchez-Leal, C. González, E. García-Isarch, and A. García. "Oceanographic scenario and fish larval distribution off Guinea-Bissau (north-west Africa)." Journal of the Marine Biological Association of the United Kingdom 95, no. 3 (December 17, 2014): 435–52. http://dx.doi.org/10.1017/s0025315414001647.

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This paper describes the hydrography and the larval fish assemblage of Guinea Bissau waters, and analyses the spatial distribution of the main families in relation to the oceanographic features of the area. Data were obtained during an oceanographic survey, undertaken between October and November 2008. In addition to 98 demersal fishing hauls, a total of 33 stations, located between 20 and 1000 m depth, were sampled for hydrography and ichthyoplankton. Data showed that Guinea-Bissauan surface waters are characterized by a strong thermohaline front that flows parallel to the bathymetry of the area. Warm surface waters (SST > 29°C) occupy the inner shelf, and colder (SST < 26°C), chlorophyll-a-rich waters take over the shelf break. Continental runoff seems responsible for the low salinity of the inner-shelf waters whereas the colder types bear thermohaline features typical of tropical Atlantic waters. These features define a scenario which favours the development of fish early life stages, reflected in the high abundance and diversity of fish larvae recorded. A total of 84 taxa of fish larvae were identified. Only the family Clupeidae accounted for 54.8% of the sampled larvae. Other important families were Carangidae (8.8%), Sparidae (8.4%) and Myctophidae (5.9%).

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Ruddick, Barry R., Neil S. Oakey, and Dave Hebert. "Measuring lateral heat flux across a thermohaline front: A model and observational test." Journal of Marine Research 68, no. 3 (May 1, 2010): 523–39. http://dx.doi.org/10.1357/002224010794657146.

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45

Yuasa, Ichiro, Eisuke Hashimoto, and Hideki Ueshima. "Nitrogen and phosphorus distributions across the thermohaline front in Kii Channel in winter." Journal of Oceanography 49, no. 4 (August 1993): 407–24. http://dx.doi.org/10.1007/bf02234957.

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46

Barbot, Simon, Anne Petrenko, and Christophe Maes. "Intermediate water flows in the western South Pacific: as revealed by individual Argo floats trajectories and a model re-analysis." Biogeosciences 15, no. 13 (July 5, 2018): 4103–24. http://dx.doi.org/10.5194/bg-15-4103-2018.

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Abstract. Thanks to the autonomous Argo floats of the OUTPACE cruise (Oligotrophy to UlTra-oligotrophy PACific Experiment) and of the THOT (TaHitian Ocean Time series) project, some features of intermediate-flow dynamics, at around 1000 m depth, within the central and western South Pacific Ocean (around 19∘ S, 156∘ E–150∘ W) are described. In the Coral Sea, we highlight minima in dissolved oxygen of 140 µmol kg−1 that are associated with the signature of a southward transport of waters between two zonal jets: from the North Vanuatu Jet to the North Caledonia Jet. This transport takes place in the core of a cyclonic eddy or via the path between a cyclonic eddy and an anticyclonic one, highlighting the importance of mesoscale dynamics in upper thermocline and surface layers. Further east, we observe a strong meridional velocity shear with long-term float trajectories going either eastward or westward in the lower thermocline. More interestingly, these trajectories also exhibit some oscillatory features. Those trajectories can be explained by a single Rossby wave of 160-day duration and 855 km wavelength. Considering the thermohaline context, we confirm the meridional shear of zonal velocity and highlight a permanent density front that corresponds to the interface between Antarctic intermediate waters and North Pacific deep waters. Hence both circulation and thermohaline contexts are highly prone to instabilities and wave propagation.

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47

Hellmer, H. H., and D. J. Olbers. "On the thermohaline circulation beneath the Filchner-Ronne Ice Shelves." Antarctic Science 3, no. 4 (December 1991): 433–42. http://dx.doi.org/10.1017/s0954102091000524.

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In the Weddell Sea oceanographic data and numerical models demonstrate that Ice Shelf Water, one ingredient in the production of Weddell Sea Bottom Water, is formed by thermohaline interaction of High Salinity Shelf Water with the base of the Filchner-Ronne ice shelves. South of Berkner Island a passage with a water column thickness of about 300 m linking the Filchner and the Ronne regimes is important for the ventilation of the sub-ice shelf cavities. To simulate the flow we tested a two-dimensional thermohaline circulation model on several sections which approximate different geometries of a sub-ice shelf channel bounded by the ocean bottom and the ice shelf base. Temperature and salinity profiles measured in front of the Filchner-Ronne ice shelves are used to force the model. The results indicate that the circulation is sensitive to both salinity (density) forcing and depth of the shelf bottom prescribed at the open boundary representing the Ronne Ice Shelf edge. Where the shelf is shallow, 400 m deep, a closed circulation cell within the Ronne cavity acts like an ice pump with accumulation rates of marine ice at the ice shelf base up to 1.5 m y−1. The total outflow at the Ronne Ice Shelf edge is supported by an inflow from the Filchner regime. Where the shelf is deeper, a flow from the Ronne into the Filchner cavity develops if the bottom salinity at the Ronne Ice Shelf edge exceeds a critical value of 34.67. Seasonal variability imposed at both edges modifies the circulation pattern at the Filchner Ice Shelf edge such that the depth and magnitude of Ice Shelf Water outflow correspond with observations in the Filchner Depression.

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Tintoré, Joaquín, Dong-Ping Wang, and Paul E. La Violette. "Eddies and thermohaline intrusions of the shelf/slope front off the northeast Spanish coast." Journal of Geophysical Research 95, no. C2 (1990): 1627. http://dx.doi.org/10.1029/jc095ic02p01627.

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49

Yanagi, Tetsuo, Toshiro Saino, Takashi Ishimaru, Hideaki Nakata, and Yukio Iwatsuki. "Interdisciplinary study on the thermohaline front at the mouth of Tokyo Bay in winter." Journal of Marine Systems 1, no. 4 (May 1991): 373–81. http://dx.doi.org/10.1016/0924-7963(91)90005-f.

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Zhu, Kelan, Kefeng Mao, Xi Chen, Jiahao Wang, and Hailang Wu. "A Case Study of the Thermohaline Fine-scale Structure of the Sub-Arctic Front." Atmosphere-Ocean 59, no. 3 (May 27, 2021): 178–89. http://dx.doi.org/10.1080/07055900.2021.1955328.

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Journal articles on the topic 'Fronts thermohalins'

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