Water circulation in the Firth of Forth, Scotland

1987 ◽  
Vol 93 (3-4) ◽  
pp. 273-284 ◽  
Author(s):  
P. P. G. Dyke
Keyword(s):  
General Circulation ◽  
Bottom Topography ◽  
Circulation Pattern ◽  
Theoretical Models ◽  
The North ◽  
Open Sea ◽  
River Outflow ◽  
The North Sea ◽  
Firth Of Forth ◽  
Wind Driven Currents

SynopsisThe Firth of Forth, in terms of physical oceanography, is part of the North Sea. The general circulation pattern in the firth must be regarded as largely speculative. There have been insufficient measurements of insufficient quality, and what evidence exists leads to the view that what circulation there is, is sluggish and varies from season to season and from year to year.A description is given of the three principal mechanisms that contribute to circulation. Tides, due initially to astronomical forces, manifest themselves in the Firth of Forth through the rise and fall of the adjacent open sea. This rise and fall, periodic in mid ocean, is no longer strictly so in the firth and neither are the tidal currents. The wind-driven currents in the sea are influenced by the earth's rotation. In the Firth of Forth, some of this influence is retained. Naturally, wind-driven currents are larger near the surface. Finally, when water of different densities meets, overturning causes convection currents. All of these effects are present to some extent in the Firth of Forth. In addition, specific account has to be taken of complicated coastal and bottom topography and river outflow. Some attempt to bring together these effects and available measurements is made in this paper. Lastly, several theoretical models are proposed which account for the magnitudes and directions of the observed steady circulation. Mathematical details are given in appendices.

Pollution of the Outer Oslofjord

1991 ◽  
Vol 24 (10) ◽  
pp. 321-322
Author(s):  
Kjell Baalsrud
Keyword(s):  
North Sea ◽  
General Circulation ◽  
Sea Water ◽  
Sewage Treatment ◽  
Circulation Pattern ◽  
Polluted Water ◽  
The North ◽  
Recreation Area ◽  
The North Sea ◽  
Sill Depth

The Outer Oslofjord has recently been subject to concern. 1. The Inner Oslofjord. Covers an area of 193 km2, is 160 m deep and is separated from the Outer Oslofjord by the narrow Drøbak sound with a sill depth of less than 20 metres. This part of the Oslofjord constitutes an enclosed body of sea water, sensitive to pollution, receiving sewage from approximately 650,000 inhabitants. In spite of modern sewage treatment, the fjord still suffers torn eutrophication problems resulting in reduced oxygen in the deep water, and areas of anoxic bottom water. The fjord is an important recreation area. 2. The Outer Oslofjord. Recent findings indicate that eutrophication is slowly increasing. An increasing eutrophication of the Outer Oslofjord wil also increase the need (and cost) of better sewage treatment in the Inner Oslofjord. 3. The North Sea. The quality of the water in the Oslofjord area is also dependent on the water it receives from the Skagerrak. The Skagerrak water will periodically receive polluted water from the southern North Sea and Kattegat. When these episodes coincide with water renewals between the Oslofjord and the Skagerrak, the fjord will receive polluted water from other countries. The Oslofjord water will in turn discharge into the Skagerrak, but due to the general circulation pattern, this will mainly influence the Norwegian south-east coast.

scholarly journals Causes of the Observed Distribution of Fish in the North Sea

1896 ◽  
Vol 4 (2) ◽  
pp. 133-138
Author(s):  
J. T. Cunningham
Keyword(s):  
North Sea ◽  
German Bight ◽  
General Circulation ◽  
Satisfactory Explanation ◽  
The North ◽  
The North Sea ◽  
Firth Of Forth ◽  
Eggs And Larvae ◽  
Distribution Of Fish ◽  
A Current

As my paper in the previous number indicates, my interest in these investigations was chiefly excited by the fact that no satisfactory explanation appeared to have been discovered for the remarkable abundance of small plaice in the German Bight of the North Sea. The explanation suggested, and held by many to be sufficient, was that there was a current from west to east which carried floating or buoyant objects towards the German shores, and that, therefore, the buoyant eggs and larvæ of the plaice were carried thither in great numbers. Dr. Fulton has recently made direct experiments on the course of the drift, by putting floating bottles into the sea in the neighbourhood of the Firth of Forth. In certain cases, out of groups of bottles put overboard at the same spot, some were afterwards found on the English Coast to the south, and others on the coast of Schleswig and the Island of Heligoland. The course thus determined for the general circulation would probably cause more of the plaice spawn, shed in the North Sea, to be conveyed to the German and Danish Coasts than to English. But the difficulty that perplexed me was that the peculiarity of the German grounds seemed to consist not in the greater numbers of plaice generally, but in the exclusive occurrence of small plaice at distances from land at which, on the opposite English Coast, large mature plaice seemed also to occur with the small.

scholarly journals Quality of outdoor and indoor environment during the cruise of the tall ship STS Fryderyk Chopin

2018 ◽  
Vol 49 ◽  
pp. 00024
Author(s):  
Szymon Firląg
Keyword(s):  
Relative Humidity ◽  
Ventilation System ◽  
Pm 2.5 ◽  
The North ◽  
University Of Technology ◽  
Open Sea ◽  
The North Sea ◽  
Pm 10 ◽  
The Impact

The aim of this paper is to present the results of measurements, on the quality of internal and external environment, carried out during the cruise of the tall ship STS Fryderyk Chopin. The cruise took place between 16th and 30th September 2017 as part of the scientific seminar of the Warsaw University of Technology (WUT) on the Wave, addressed to students of the WTU. After leaving the port of Edinburgh, crossing the North Sea, the Danish straits, stops in Copenhagen and Kołobrzeg, the tall ship reached Szczecin after two weeks. The measurements carried out on the deck included the temperature and relative humidity of the indoor air in three cabins and the men’s bathroom. In two cabins, the CO2 concentration was measured additionally. The outdoor temperature, relative humidity and concentration of PM 1.0, PM 2.5 and PM 10 were also measured. The obtained results allowed to assess the quality of the internal environment in accordance with the standards and to analyze the effectiveness of the mechanical ventilation system. Measurements of particulate matter have shown significant differences between outdoor air quality in the open sea and in ports or near major shipping routes. It turned out that the impact of emissions from passing ships using diesel engines is clearly visible.

The source-sink flow in a rotating system and its oceanic analogy

1971 ◽  
Vol 45 (3) ◽  
pp. 441-464 ◽  
Author(s):  
Han-Hsiung Kuo ◽  
George Veronis
Keyword(s):  
Ocean Circulation ◽  
Bottom Topography ◽  
Circulation Model ◽  
Circulation Pattern ◽  
Theoretical Models ◽  
Outer Wall ◽  
Western Boundary ◽  
Shaped Container ◽  
Laboratory Analogue ◽  
Source Sink

Laboratory analogues of theoretical models of wind-driven ocean circulation are based on ideas presented by Stommel (1957). A particularly simple demonstration of the applicability of these ideas is contained in a paper by Stommel, Arons & Faller (1958). The present work develops the source-sink laboratory analogue of ocean circulation models to a point where chosen parametric values allow one to simulate the theoretical models of Stommel (1948) and Munk (1950) exactly. The investigation of the flow in a rotating cylinder generated by a source of fluid near the outer wall leads to a detailed description of the roles of the various boundary layers which occur. This knowledge is used to analyse the more complex source-sink flow in a pie-shaped basin. The laboratory analogue to the Stommel circulation model is analyzed in detail. It is shown that the change in the flow pattern brought about by a radial variation of the position of the eastern boundary in the pie-shaped basin is confined to the interior flow and the boundary layer is largely unaffected. When the bottom of the pie-shaped container slopes, the circulation pattern is changed significantly. For the particular case treated, the depth of the basin along the western boundary is unchanged and the maximum depth occurs at the southeast corner. The circulation generated by a source introduced at the apex of the pie has a gyre whose centre is shifted more toward the southwest corner than the corresponding centre of the gyre for a flat-bottomed basin. Two experiments are reported showing that the western boundary may separate because of the effect of bottom topography or because of the pressure of a cyclonic and an anti-cyclonic gyre generated by suitably placed sources and sinks.

scholarly journals Contribution of atmospheric circulation to recent off-shore sea-level variations in the Baltic Sea and the North Sea

2018 ◽  
Vol 9 (1) ◽  
pp. 69-90 ◽  
Author(s):  
Sitar Karabil ◽  
Eduardo Zorita ◽  
Birgit Hünicke
Keyword(s):  
Baltic Sea ◽  
Sea Level ◽  
North Sea ◽  
Circulation Pattern ◽  
Net Energy ◽  
The Baltic Sea ◽  
Sea Level Variability ◽  
The North ◽  
The North Sea ◽  
The Baltic

Abstract. The main purpose of this study is to quantify the contribution of atmospheric factors to recent off-shore sea-level variability in the Baltic Sea and the North Sea on interannual timescales. For this purpose, we statistically analysed sea-level records from tide gauges and satellite altimetry and several climatic data sets covering the last century. Previous studies had concluded that the North Atlantic Oscillation (NAO) is the main pattern of atmospheric variability affecting sea level in the Baltic Sea and the North Sea in wintertime. However, we identify a different atmospheric circulation pattern that is more closely connected to sea-level variability than the NAO. This circulation pattern displays a link to sea level that remains stable through the 20th century, in contrast to the much more variable link between sea level and the NAO. We denote this atmospheric variability mode as the Baltic Sea and North Sea Oscillation (BANOS) index. The sea-level pressure (SLP) BANOS pattern displays an SLP dipole with centres of action located over (5° W, 45° N) and (20° E, 70° N) and this is distinct from the standard NAO SLP pattern in wintertime. In summertime, the discrepancy between the SLP BANOS and NAO patterns becomes clearer, with centres of action of the former located over (30° E, 45° N) and (20° E, 60° N). This index has a stronger connection to off-shore sea-level variability in the study area than the NAO in wintertime for the period 1993–2013, explaining locally up to 90 % of the interannual sea-level variance in winter and up to 79 % in summer. The eastern part of the Gulf of Finland is the area where the BANOS index is most sensitive to sea level in wintertime, whereas the Gulf of Riga is the most sensitive region in summertime. In the North Sea region, the maximum sea-level sensitivity to the BANOS pattern is located in the German Bight for both winter and summer seasons. We investigated, and when possible quantified, the contribution of several physical mechanisms which may explain the link between the sea-level variability and the atmospheric pattern described by the BANOS index. These mechanisms include the inverse barometer effect (IBE), freshwater balance, net energy surface flux and wind-induced water transport. We found that the most important mechanism is the IBE in both wintertime and summertime. Assuming a complete equilibration of seasonal sea level to the SLP gradients over this region, the IBE can explain up to 88 % of the sea-level variability attributed to the BANOS index in wintertime and 34 % in summertime. The net energy flux at the surface is found to be an important factor for the variation of sea level, explaining 35 % of sea-level variance in wintertime and a very small amount in summer. The freshwater flux could only explain 27 % of the variability in summertime and a negligible part in winter. In contrast to the NAO, the direct wind forcing associated with the SLP BANOS pattern does not lead to transport of water from the North Sea into the Baltic Sea in wintertime.

Ever-Present Dangers

2000 ◽  
Author(s):  
John H. Lienhard
Keyword(s):  
Full Range ◽  
Is Success ◽  
The North ◽  
Queen Victoria ◽  
Cost Cutting ◽  
The World ◽  
The North Sea ◽  
Firth Of Forth ◽  
The One ◽  
Recurrent Theme

A murderously recurrent theme surfaces as we read the record of technology. It can be decocted into the tidy epigram: “The fastest route to success is through failure. The greatest enemy of success is success.” When my civil engineering colleague Jack Matson recognized the validity of that idea, he began vigorously to promote the concept of intelligent fast failure. He said that we can speed our own creativity if we begin by running through as many wrong or foolish ways of accomplishing our end as we can think of. That process both emboldens us and instructs us in the full range of possibility. Conversely, success that fails to keep the boundaries of error within sight eventually takes itself for granted and leaves us open to failure on a grand scale. We skirted this issue toward the end of Chapter 9; now let us look at it more closely. A story of three bridges helps to expose the complex way in which success and failure work together. Henry Petroski takes us back to the forty-six-mile rail trip from Edinburgh to Dundee, which took half a day in 1870. Passengers had to ride the ferry over two wide fjords, arms of the North Sea slicing into Scotland. They are the Firth of Tay and the Firth of Forth. Then an English engineer, Thomas Bouch, sold backers on the idea of building bridges over those inlets. The first was an immense two-mile bridge over the Firth of Tay. When its eighty-five spans were finished in 1877, they made up the longest bridge in the world, and Queen Victoria knighted Bouch. Disaster followed almost immediately. The Tay Bridge collapsed in 1879, killing seventy-five people. Cost-cutting had yielded a bridge that couldn’t stand up to the wind forces. Bouch died in humiliation four months later. By 1881 the Tay Bridge had been rebuilt with heavy, unbeautiful trusses, and attention turned to the second bridge, the one over the Firth of Forth. The Firth of Forth bridge was to cross where the center of the firth was a mile wide, with only one shallow spot for a central pier.

Distribution of the Cirratulid Polychaetes Dodecaceria Fimbriata, D. Concharum and D. Diceria in European Waters Between Latitudes 48°N and 70°N

1996 ◽  
Vol 76 (3) ◽  
pp. 625-635 ◽  
Author(s):  
Peter H. Gibson
Keyword(s):  
North Sea ◽  
Coastal Waters ◽  
Northern Europe ◽  
English Channel ◽  
The North ◽  
The North Sea ◽  
Firth Of Forth ◽  
First Time

The distribution of Dodecaceria in northern Europe was found for samples borrowed from museums and other collections. Dodecaceria fimbriata was present in the coastal waters of mainland Britain and the Continent from the English Channel northwards. Dodecaceria concharum was only found in British mainland coastal waters and on the French coast at the western end of the English Channel. It was absent where salinities were below ~34%0. The two species were sampled along the Lothian and Borders coasts and the numbers of D. concharum fell with decreasing salinity as the Firth of Forth was approached. Dodecaceria diceria was found for the first time in the North Sea at depths of 100–200 m. The benthic salinity here is ~35%0.

scholarly journals XII.—On the Carboniferous Volcanic Rocks of the Basin of the Firth of Forth—their Structure in the Field and under the Microscope

1880 ◽  
Vol 29 (1) ◽  
pp. 437-518 ◽  
Author(s):  
Geikie
Keyword(s):  
North Sea ◽  
Geographical Area ◽  
Volcanic Rocks ◽  
The South ◽  
The West ◽  
Red Sandstone ◽  
Lower Silurian ◽  
The North ◽  
The North Sea ◽  
Firth Of Forth

The geographical area embraced in the present memoir forms a well-marked basin traversed along its centre by the estuary of the Forth. It is bounded on the north by the chain of the Ochil Hills, on the south by the range of the Pentland and Lammermuir uplands. Towards the west it joins along a low watershed the basin of the Clyde, while eastwards it dips under the waters of the North Sea. Within this defined space the Carboniferous rocks occupy what may be described as one great synclinal trough, varied by innumerable smaller synclines and anticlines. Save where cut out by powerful dislocations, their lower members rise up along the margins of the basin, while their highest portions cover a smaller area in the centre. The older formations forming the northern and southern boundaries of the area belong chiefly to the Lower Old Red Sandstone, in the Lammermuir district to the Lower Silurian. The Carboniferous rocks everywhere rest upon them unconformably.

A mathematical model of a river—shallow sea system used to investigate tide, surge and their interaction in the Thames—southern North Sea region

1974 ◽  
Vol 275 (1255) ◽  
pp. 567-609 ◽  
Keyword(s):  
Mathematical Model ◽  
Sea Level ◽  
North Sea ◽  
Southern Bight ◽  
The North ◽  
Open Sea ◽  
The North Sea ◽  
Good Potential ◽  
Tidal Oscillation ◽  
The One

A mathematical model is used to reproduce tidal and surge motion in the Thames Estuary and the Southern Bight of the North Sea. The model is based on a numerical finite-difference solution of the nonlinear hydrodynamical equations representing motion in the area. The equations are nonlinear in so far as they include quadratic bottom friction and allow for time variations in the total depth of water; the inclusion of advective terms is limited to the river. Solution of the one-dimensional equations for the river and the two-dimensional equations for the sea takes place within a single computational array. The scheme for calculating motion in the sea is similar to that developed by Heaps (1969), and the scheme for the river was developed by Rossiter & Lennon (1965). Tidal and surge motion within the model are reproduced by specifying the initial tidal contours of the sea, the external influences of surge and tidal oscillation along the open sea boundaries, and wind stresses over the sea surface. Computations have been concerned with generating lunar tidal oscillations for the construction of an M2 co-tidal chart, and investigating the interaction between tides and surges, in this region of shallow waters. The investigation of interaction involved calculating the sea’s response to the separate and combined effects of tidal and meteorological forces, whence the effects of a tide on a surge were deduced, possibly for the first time at offshore locations. Computed interaction phenomena for the period of a severe storm surge, 15 to 17 February 1962, were found to accord with the results of Proudman (19550, b, J957) and Rossiter (1961). Agreement between computed sea-level disturbances and actually recorded disturbances for this surge period revealed that the model has good potential for simulating sea level disturbances which occur in nature.

Partial validation of a numerical model for tidal motion in the Tay Estuary

1987 ◽  
Vol 92 (3-4) ◽  
pp. 275-283
Author(s):  
D. J. Gunn ◽  
J. McManus ◽  
O. Yenigun
Keyword(s):  
Mathematical Model ◽  
Numerical Model ◽  
Boundary Conditions ◽  
North Sea ◽  
Integral Method ◽  
The Road ◽  
Tidal Motion ◽  
The North ◽  
Open Sea ◽  
The North Sea

SynopsisIn a mathematical model of the Tay (Gunn & Yenigun 1987) based upon the Local Integral Method (Gunn & Yenigun 1985), tidal levels at the seaward boundaries and velocities at landward boundaries are used in setting boundary conditions, so that validation studies are mainly based upon changes in internal tidal levels, and comparison between computed and measured velocities within the modelled region. The comparisons of tidal levels within this estuary over a 5.0 m tide showed agreement with overall values from Buddon Ness to the rail bridge, but within the overall agreement there were significant differences in the immediate vicinity of the road bridge. Velocities predicted within the estuary have been compared with measurements provided by a number of surveys in the period from 1972-78. The agreement between experiment and prediction was good in the central and western regions of the model, but the comparison between measurement and prediction was less good near the eastern boundaries. The principal reason for poorer agreement in the east was the difficulty in setting boundary conditions at the open sea extremes of the model. The most satisfactory way of improving the model near the open sea boundaries would be to link the model for the Tay with a model for velocity and level in the North Sea.

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