scholarly journals A modeling study on tides in the Port of Vancouver

2019 ◽  
Vol 2 (1) ◽  
pp. 101-125 ◽  
Author(s):  
Yongsheng Wu ◽  
Charles Hannah ◽  
Mitchell O’Flaherty-Sproul ◽  
Phillip MacAulay ◽  
Shiliang Shan
Keyword(s):  
Three Dimensional ◽  
Ocean Model ◽  
Tidal Currents ◽  
Momentum Balance ◽  
Tidal Asymmetry ◽  
Residual Circulation ◽  
Dynamic Mechanisms ◽  
Tidal Flows ◽  
Residual Flows ◽  
Good Agreement

In the present paper, tides in the port of Vancouver Harbour have been investigated with a high-resolution three-dimensional hydrodynamic model based on FVCOM (Finite Volume Community Ocean Model). The model was evaluated against field observations including tidal elevations and tidal currents, and the evaluation showed that the model was in good agreement with the observational data. Using the model, we first investigated the horizontal distributions of tides, tidal currents, and tidally induced residual circulation, and then investigated the tidal asymmetry and dynamic mechanisms of tidal flows in the harbour. The tidal residual circulation shows a strong spatial pattern, which is associated with the local coastlines and variation of topography. The tidal asymmetry in the harbour is caused by different mechanisms, not only including the traditional factors, such as residual flows, the interaction between M2 and its overtide M4, but also the interaction of principal astronomical tides of O1, K1, and M2. The momentum balance is dominated by terms of the advection and the pressure gradient in First Narrows and Second Narrows, whereas terms of the local acceleration and the Coriolis are also important in the central harbour. The spatial variations of the momentum terms are strongly associated with the local changes in coastline and topography.

scholarly journals A Numerical Simulation of Extratropical Storm Surge and Hydrodynamic Response in the Bohai Sea

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Yumei Ding ◽  
Lei Ding
Keyword(s):  
Storm Surge ◽  
Bohai Sea ◽  
Model Simulation ◽  
Three Dimensional ◽  
Wrf Model ◽  
Ocean Model ◽  
Tidal Currents ◽  
The Bohai Sea ◽  
Hydrodynamic Response ◽  
Coastal Ocean Model

A hindcast of typical extratropical storm surge occurring in the Bohai Sea in October 2003 is performed using a three-dimensional (3D) Finite Volume Coastal Ocean Model (FVCOM). The storm surge model is forced by 10 m winds obtained from the Weather Research Forecasting (WRF) model simulation. It is shown that the simulated storm surge and tides agree well with the observations. The nonlinear interaction between the surge and astronomical tides, the spatial distribution of the maximum surge level, and the hydrodynamic response to the storm surge are studied. The storm surge is the interaction of the surge and the astronomical tides. The currents change rapidly during the storm surge and turn to be the unidirectional at some places where the tidal currents are usually rectilinear. The results show that the local surge current velocity in each depth, with a magnitude of the same order as the astronomic tidal currents, increases or decreases rapidly depending on the relationship between the winds and current directions. Furthermore, the current pattern gets more complicated under the influence of the direction of the winds, which might affect sand movement in the coastal water of the Bohai Sea.

scholarly journals Tidal influences on a future evolution of the Filchner–Ronne Ice Shelf cavity in the Weddell Sea, Antarctica

2018 ◽  
Vol 12 (2) ◽  
pp. 453-476 ◽  
Author(s):  
Rachael D. Mueller ◽  
Tore Hattermann ◽  
Susan L. Howard ◽  
Laurie Padman
Keyword(s):  
Ocean Circulation ◽  
Three Dimensional ◽  
Ocean Model ◽  
Tidal Currents ◽  
Weddell Sea ◽  
Ice Shelf ◽  
Ice Streams ◽  
Future Evolution ◽  
History Of ◽  
Basal Melting

Abstract. Recent modeling studies of ocean circulation in the southern Weddell Sea, Antarctica, project an increase over this century of ocean heat into the cavity beneath Filchner–Ronne Ice Shelf (FRIS). This increase in ocean heat would lead to more basal melting and a modification of the FRIS ice draft. The corresponding change in cavity shape will affect advective pathways and the spatial distribution of tidal currents, which play important roles in basal melting under FRIS. These feedbacks between heat flux, basal melting, and tides will affect the evolution of FRIS under the influence of a changing climate. We explore these feedbacks with a three-dimensional ocean model of the southern Weddell Sea that is forced by thermodynamic exchange beneath the ice shelf and tides along the open boundaries. Our results show regionally dependent feedbacks that, in some areas, substantially modify the melt rates near the grounding lines of buttressed ice streams that flow into FRIS. These feedbacks are introduced by variations in meltwater production as well as the circulation of this meltwater within the FRIS cavity; they are influenced locally by sensitivity of tidal currents to water column thickness (wct) and non-locally by changes in circulation pathways that transport an integrated history of mixing and meltwater entrainment along flow paths. Our results highlight the importance of including explicit tidal forcing in models of future mass loss from FRIS and from the adjacent grounded ice sheet as individual ice-stream grounding zones experience different responses to warming of the ocean inflow.

scholarly journals Lateral Circulation in a Partially Stratified Tidal Inlet

2018 ◽  
Author(s):  
Linlin Cui ◽  
Haosheng Huang ◽  
Chunyan Li ◽  
Dubravko Justic
Keyword(s):  
Pressure Gradient ◽  
Three Dimensional ◽  
Model Performance ◽  
Ocean Model ◽  
Tidal Inlet ◽  
Momentum Balance ◽  
Lateral Velocity ◽  
Short Period ◽  
Lateral Circulation ◽  
Differential Advection

Using a three-dimensional, hydrostatic, primitive-equation ocean model, this study investigates the dynamics of lateral circulation in a partially stratified tidal inlet, the Barataria Pass in the Gulf of Mexico, over a 25.6-hour diurnal tidal cycle. Model performance is assessed against observational data. During flood tide, the lateral circulation exhibits the characteristics similar to that induced by differential advection, i.e., lateral flow consists of two counter-rotating cells and is convergent at the surface. The analysis of momentum balance indicates that, in addition to the pressure gradient and vertical stress divergence, nonlinear advection and horizontal stress divergence are also important contributors. During ebb phase, the lateral circulation is mostly eastward for the whole water column and persisting for almost the whole period. The surface divergence suggested by the differential advection mechanism lasts for a very short period, if it ever exists. The main momentum balance across most of the transect during ebb is between the along-channel advection of cross-channel momentum and pressure gradient. The sectional averaged lateral velocity magnitude during ebb is comparable to that during flood, which is different from the idealized numerical experiment result.

Tidal currents and mixing in the Gulf of St. Lawrence: an application of the incremental approach to data assimilation

2001 ◽  
Vol 58 (4) ◽  
pp. 723-735 ◽  
Author(s):  
Youyu Lu ◽  
Keith R Thompson ◽  
Daniel G Wright
Keyword(s):  
Data Assimilation ◽  
Three Dimensional ◽  
Tidal Currents ◽  
Tide Gauges ◽  
Three Dimensional Model ◽  
Density Profiles ◽  
Water Column Stability ◽  
Incremental Approach ◽  
Tidal Frequency ◽  
Good Agreement

Tidal heights from 19 tide gauges around the Gulf of St. Lawrence are assimilated into a fully nonlinear, three-dimensional model using the incremental approach to data assimilation. The predicted sea level fields are realistic and agree with the assimilated tidal heights to within about 0.05 m at the M2 tidal frequency. The model also predicts tidal currents with useful skill. The prediction error at the M2 tidal frequency is typically less than 0.05 m·s–1. The maps of predicted tidal currents are used to identify regions of mixed and stratified water in the Gulf of St. Lawrence using a version of the Simpson–Hunter stability parameter, E. Overall, the map of E is in good agreement with a direct measure of water column stability based on observed density profiles.

scholarly journals Contributions to stratospheric ozone changes from ozone depleting substances and greenhouse gases

2010 ◽  
Vol 10 (4) ◽  
pp. 9647-9694 ◽  
Author(s):  
D. A. Plummer ◽  
J. F. Scinocca ◽  
T. G. Shepherd ◽  
M. C. Reader ◽  
A. I. Jonsson
Keyword(s):  
Greenhouse Gases ◽  
21St Century ◽  
Climate Model ◽  
Stratospheric Ozone ◽  
Three Dimensional ◽  
Ocean Model ◽  
Residual Circulation ◽  
Chemical Effects ◽  
Ozone Depleting Substances ◽  
Year 2000

Abstract. A state-of-the-art chemistry climate model coupled to a three-dimensional ocean model is used to produce three experiments, all seamlessly covering the period 1950–2100, forced by different combinations of long-lived Greenhouse Gases (GHGs) and Ozone Depleting Substances (ODSs). The experiments are designed to investigate the mechanisms by which GHGs and ODSs affect the evolution of ozone, including changes in the Brewer-Dobson circulation of the stratosphere and cooling of the upper stratosphere by CO2. Separating the effects of GHGs and ODSs on ozone, we find the decrease in upper stratospheric ozone from ODSs up to the year 2000 is approximately 30% larger than the actual decrease in ozone due to the offsetting effects of cooling by increased CO2. Over the 21st century, as ODSs decrease, continued cooling from CO2 is projected to account for more than 50% of the projected increase in upper stratospheric ozone. Changes below 20 hPa show a redistribution of ozone from tropical to extra-tropical latitudes with an increase in the Brewer-Dobson circulation, while globally averaged the amount of ozone below 20 hPa decreases over the 21st century. Further analysis by linear regression shows that changes associated with GHGs do not appreciably alter the recovery of stratospheric ozone from the effects of ODSs; over much of the stratosphere ozone recovery follows the decline of halogen concentrations within statistical uncertainty, though the lower polar stratosphere of the Southern Hemisphere is an exception with ozone concentrations recovering more slowly than indicated by the halogen concentrations. These results also reveal the degree to which climate change, and stratospheric CO2 cooling in particular, mutes the chemical effects of N2O on ozone in the standard future scenario used for the WMO Ozone Assessment. Increases in the residual circulation of the atmosphere and chemical effects from CO2 cooling more than halve the increase in reactive nitrogen in the mid to upper stratosphere that results from the specified increase in N2O between 1950 and 2100.

scholarly journals Lateral Circulation in a Partially Stratified Tidal Inlet

2018 ◽  
Vol 6 (4) ◽  
pp. 159 ◽  
Author(s):  
Linlin Cui ◽  
Haosheng Huang ◽  
Chunyan Li ◽  
Dubravko Justic
Keyword(s):  
Pressure Gradient ◽  
Three Dimensional ◽  
Model Performance ◽  
Ocean Model ◽  
Tidal Inlet ◽  
Momentum Balance ◽  
Lateral Velocity ◽  
Short Period ◽  
Lateral Circulation ◽  
Differential Advection

Using a three-dimensional, hydrostatic, primitive-equation ocean model, this study investigates the dynamics of lateral circulation in a partially stratified tidal inlet, the Barataria Pass in the Gulf of Mexico, over a 25.6 h diurnal tidal cycle. Model performance is assessed against observational data. During flood tide, the lateral circulation exhibits the characteristics similar to those induced by differential advection, i.e., lateral flow consists of two counter-rotating cells and is convergent at the surface. The analysis of momentum balance indicates that, in addition to the pressure gradient and vertical stress divergence, nonlinear advection and horizontal stress divergence are also important contributors. During ebb phase, the lateral circulation is mostly toward the right shoal (when looking into the estuary) for the whole water column and persisting for almost the whole period. The surface divergence suggested by the differential advection mechanism lasts for a very short period, if it ever exists. The main momentum balance across most of the transect during ebb is between the along-channel advection of cross-channel momentum and pressure gradient. The sectional averaged lateral velocity magnitude during ebb is comparable to that during flood, which is different from the idealized numerical experiment result.

scholarly journals Skill tests of three-dimensional tidal currents in a global ocean model: A look at the North Atlantic

2012 ◽  
Vol 117 (C8) ◽  
pp. n/a-n/a ◽  
Author(s):  
Patrick G. Timko ◽  
Brian K. Arbic ◽  
James G. Richman ◽  
Robert B. Scott ◽  
E. Joseph Metzger ◽  
...  
Keyword(s):  
North Atlantic ◽  
Three Dimensional ◽  
Ocean Model ◽  
Tidal Currents ◽  
Global Ocean ◽  
The North ◽  
The North Atlantic

scholarly journals Tidal influences on a future evolution of the Filchner-Ronne Ice Shelf cavity in the Weddell Sea, Antarctica

2017 ◽  
Author(s):  
Rachael D. Mueller ◽  
Tore Hattermann ◽  
Susan L. Howard ◽  
Laurence Padman
Keyword(s):  
Ocean Circulation ◽  
Three Dimensional ◽  
Ocean Model ◽  
Tidal Currents ◽  
Weddell Sea ◽  
Ice Shelf ◽  
Ice Streams ◽  
Future Evolution ◽  
History Of ◽  
Basal Melting

Abstract. Recent modeling studies of ocean circulation in the southern Weddell Sea, Antarctica, project an increase over this century of ocean heat into the cavity beneath Filchner-Ronne Ice Shelf (FRIS). This increase in ocean heat would lead to more basal melting and a modification of the FRIS ice draft. The corresponding change in cavity shape will affect advective pathways and the spatial distribution of tidal currents, which play important roles in basal melting under FRIS. These feedbacks between heat flux, basal melting, and tides will affect the evolution of FRIS under the influence of a changing climate. We explore these feedbacks with a three-dimensional ocean model of the southern Weddell Sea that is forced by thermodynamic exchange beneath the ice shelf and tides along the open boundaries. Our results show regionally-dependent feedbacks that, in some areas, substantially modify the melt rates near the grounding lines of buttressed ice streams that flow into FRIS. These feedbacks are introduced by variations in meltwater production as well as the circulation of this meltwater within the FRIS cavity; they are influenced locally by sensitivity of tidal currents to water column thickness and non-locally by changes in circulation pathways that transport an integrated history of mixing and meltwater entrainment along flow paths. Our results highlight the importance of including explicit tidal forcing in models of future mass loss from FRIS and from the adjacent grounded ice sheet as individual ice stream grounding zones experience different responses to warming of the ocean inflow.

scholarly journals Super Residual Circulation: a new perspective on ocean vertical heat transport

2021 ◽  
Author(s):  
Abhishek Savita ◽  
Jan D. Zika ◽  
Catia M. Domingues ◽  
Simon J. Marsland ◽  
Gwyn Dafydd Evans ◽  
...  
Keyword(s):  
Heat Transport ◽  
Ocean Circulation ◽  
Three Dimensional ◽  
Horizontal Resolution ◽  
Ocean Model ◽  
Small Scale ◽  
Residual Circulation ◽  
Overturning Circulation ◽  
Vertical Heat ◽  
Diabatic Processes

AbstractOcean circulation and mixing regulate Earth’s climate by moving heat vertically within the ocean. We present a new formalism to diagnose the role of ocean circulation and diabatic processes in setting vertical heat transport in ocean models. In this formalism we use temperature tendencies, rather than explicit vertical velocities to diagnose circulation. Using quasi-steady state simulations from the Australian Community Climate and Earth-System Simulator Ocean Model (ACCESS-OM2), we diagnose a diathermal overturning circulation in temperature-depth space. Furthermore, projection of tendencies due to diabatic processes onto this coordinate permits us to represent these as apparent overturning circulations. Our framework permits us to extend the concept of Super-Residual Transport (SRT), which combines mean and eddy advection terms with subgridscale isopycnal mixing due to mesoscale eddies, but excludes small-scale three dimensional turbulent mixing effect, to construct a new overturning circulation – the ‘Super Residual Circulation’ (SRC).We find that in the coarse resolution version of ACCESS-OM2 (nominally 1° horizontal resolution) the SRC is dominated by an ~11 Sv circulation which transports heat upward. The SRC’s upward heat transport is ~2 times larger in a finer horizontal resolution (0.1°) version of ACCESS, suggesting a differing balance of super-residual and parameterized small-scale processes may emerge as eddies are resolved. Our analysis adds new insight into super-residual processes, as the SRC elucidates the pathways in temperature and depth space along which watermass transformation occurs.

A Three-Dimensional Numerical Simulation of Heat Transport in the Coastal Areas of the Houshi Power Plant

2011 ◽  
Vol 356-360 ◽  
pp. 2718-2724
Author(s):  
Mu Lan Zhu ◽  
Long Yan Cai ◽  
Wen Zhi Cao ◽  
Quan Lin Zhou
Keyword(s):  
Power Plant ◽  
Heat Transport ◽  
Waste Heat ◽  
Three Dimensional ◽  
Ocean Model ◽  
Coastal Areas ◽  
Observation Data ◽  
Thermal Discharge ◽  
Proposed Model ◽  
Good Agreement

The thermal discharge from the Houshi power plant has been increased continuously with the increase in power supply. In order to understand the waste heat pollution conditions in the coastal areas of the Houshi power plant, we proposed a modified Princeton Ocean Model (POM) model to conduct three-dimensional numerical simulations for heat transport in the coastal areas of the plant. The proposed model was verified using observation data in 2002 under previous operational condition of the power plant with a thermal discharge of . The verification results indicate that the simulation results of heat transport have a good agreement with observation ones.

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