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Position, Territory and Structure
The British Isles are situated on the continental shelf off the north-west coast of Europe and comprise a group of islands lying between latitudes 50o and 60°N and longitudes 1o45, and 8° 10' West, the prime meridian of 0 passing through the old observatory of Greenwich (London). The total area of the British Isles is 322,246 square km.
Britain, formally known as the United Kingdom of Great Britain and Northern Ireland, constitutes the greater part of the islands. It comprises the mainland of England, Wales and Scotland (Great Britain) and the northern part of Ireland (Northern Ireland). The southern part of Ireland, the second largest island of the group, is the Irish Republic or Eire. All in all there are over 5,000 islands in the system of the British Isles.
The United Kingdom's area is some 244,100 square km, of which about; 99 per cent is land and the remainder inland water. This is nearly the same size as the Federal Republic of Germany, New Zealand and half the size of France. From south to north it stretches for over 900 km, and is just under 500 km across in the widest part and 60 km in the narrowest. Due to the numerous bays and inlets no place in Britain is as much as 120 km from the sea coast line. The combined population of the British Isles - 59.5 million people (including that of the Republic of Ireland) makes the islands one of the most densely populated parts of the earth's surface and the United Kingdom, at least, one of the most densely populated countries.
With nearly 59 million people, Great Britain ranks about fourteenth in the world in terms of population. The high density of population (about 250 per square kilometre) sets a problem of land use and of livelihood. Within the British Isles it implies a pressure on land, a pressure reflected both in competition for space and in intensive agriculture. The problems of supporting such a large population on such a small land area are obvious. In fact, this became possible with the emergence of Britain as the world,s first industrial nation during the eighteenth and early nineteenth centuries. It was during this period that Britain acquaired vast overseas colonial territories, ruthlessly robbed and exploited them. This enabled her to become the wealthiest nation on earth.
Off the north-western coast of Great Britain there is a group of islands known as the Hebrides. They are divided into the Inner and Outer Hebrides, the groups of islands, separated from each other by the Sea of the Hebrides and the Little Minch. These groups of islands represent the higher unsubmerged portions of a dissected block broadly similar to the main highland mass.
Life in the Hebrides very much resembles that of the West coast of the mainland. Many of the people are crofters, and farming combined with fishing is the main occupation. The island of Lewis-Harris, the largest and most northerly of the Outer Hebrides, is particularly notable for the traditional domestic Industry of spinning wool from local sheep and the weaving it into tweeds. This Industry is largely concentrated in Storno-way, which is also a minor fishing port. Out of over the total of 500 islands of the Hebrides more than half are inhabitable. Only several families live on some of them.
Separated from the mainland by the stormy seven-mile wide Pentland Firth there are the Orkney Islands, comprising about a hundred islands, though only a third are Inhabited, by about 19,500 people. Most of the people are engaged in dairy- and poultry farming. Bacon, cheese and eggs are exported to Central Scotland.
Situated about 70 miles north of the Orkneys are the Shetland Islands, which provide thin, infertile soils suitable only for rough pasture. The total population is about 18,000. The Shetland farmers are essentially crofters, but during the summer months they are actively engaged in herring-fishing. Apart from fish, the only exports from the islands are Shetland ponies and lace knitted from the wool of local sheep. Lerwick, the chief settlement, contains about 5,000 people, but the Shetlands are far from prosperous, and the population is still steadily decreasing.
In the middle of the Irish Sea there is the Isle of Man (571 square km). The island is administered by its own Manx Parliament and has a population of about 50.000 chiefly engaged in farming, fishing and tourist trade. The only settlement of any size is the holiday resort of Douglas (23,000). Another important island in the Irish Sea is Anglesey, situated off the north coast of Wales. Anglesey contains only 52,000 people, and more of the working population are now engaged in industry than in fishing and agriculture. This is due partly to an increase in the tourist trade and partly to the introduction of several new industries, for example, the construction and eventual operation of the nuclear power station at Wylfa.
The Isle of Wight isin the English Channel. It is diamond-shaped, 40 km from west to east, and about half as much from north to south. The Isle of Wight lies across the southern end of Southampton Water, and is separated from the mainland by the Solent. With its sunny beaches and pleasant varied countryside, the island forms one of the South Coast's most important tourist resorts. It is linked to London by ferry and rail services. The decline of light and other industries has presented serious problems of employment for the island, and at present the population is being reduced by migration to the mainland, where the situation is far from being better.
Off the extreme south-western coast of Great Britain there is a tiny group of the Isles of Scilly.
The Channel Islands lie to the south-weston theFrench side of the English Channel. Theyare known to the French as the Isles Normandes, and their position canindeed be best seen from a map of north-west France than southern England.
The Channel Islands form an archipelago, detachedbyshallow waters from the Cotentin peninsula in Normandy. As part of the Duchy of Normandy, they have been attached to the English Crown since the Norman Conquest (1066).
The population of the Channel Islands (over 133,000) isdistributedover a total area of only 194 sq.km. This results in a high density of population - 686 per sq km - throughout the islands, greatly increased in summer by holiday-makers. Here there is a strict legislation over immigration and the purchase of property.
In the rural areas many of the people speak a French-Norman dialect, but the official languages are English and French, the former gradually becoming, the more important.
The chief industry on the islands Is tourism. Each one has its own coastal attractions, but their main asset, as far as holiday visitors are concerned, la their climate. They enjoy very mild winters compared with the rest of the British Isles. Moreover, the duration of sunshine is high-over five hours per day throughout the year, while rainfall is about the same as that of the Hampshire Basin (southern England) - 700-1000 mm annually. These factors, coupled with a long growing season, give favourable conditions for agriculture as well as holiday-making.
The chief Islands of the group are Jersey and Guernsey. Jersey (76,000) is the largest and most populous island, it occupies 60 per cent of the total area and has almost 60 per cent of the population. Its northern coast is lined with granite cliffs, and the land slopes down to low sandy bays on the north coast. This southerly aspect helps the cultivation of early potatoes and tomatoes in the open air. Jersey alsoraises and exports the dairy cattle named after it. The chief town of the island, St.Helier, is on the south coast.
Guernsey (53,000) slopes gradually downwards in the opposite direction, the plateau descending from the cliff-lined south coast to the north. Market gardening is largely carried out under glass. Tomatoes and flowers are leading crops. Guernsey is famous for its nativebreed of cattle. The chief town is St. Peter Porton the east coast.
Smaller islands include Alderney (2,000) and Sark (600)-the islands without motor-cars.
The British Isles are of the continental origin. Situated off the north-west coast of Europe, they once formed part of that continent. The only became islands when they were separated from it. The separation took place thousands of years ago, after the last Ice Age. When the ice melted, the level of the oceans rose and drowned the low-lying coastlands round the continents. This was when the English Channel, which was formerly a westward extension of the North European Plain, became a shallow stretch of sea. It was a change which greatly affected the history as well as the geography of these islands.
It seems probable that the last glacial advance was at its maximum about 20,000 years ago. Since then a general warmingofthe climate has caused the glaciers to shrink, until today they have disappeared entirely from the British Isles. The withdrawal of the ice had an influence on the development of coastal features,for with the melting of theice much water "locked up" inthe glaciers was returned to the sea. As a result, sea-level during the post-glacial period rose by over 60 m. It was during this rise in sea-level that Britain was separated from the continent of Europe by the formation of the Strait of Dover. Other coastal areas suffered "drowning" with various results. In western Scotland glaciated valleys were flooded to form sea-lochs, the smaller islands were separated from Great Britain and Ireland, and in England the lower parts of manyrivervalleys were submerged to form deeply penetrating inlets.
Around the coasts of north-west Europe the land slopes gently down into the sea. At a certain depth of sea the slope becomes steeper, and the sea bed descends to much deeper levels. This change of slope takes place at a sea depth of about 200 m.
The zone of shallow water whichat present surrounds the continent thus resembles a shelf above the really deep wateroftheoceans: it is called the continental shelf. A line joining points at a depth of 200 m shows the approximate boundaryofthe continental shelf. The BritishIsles lie entirely on the shelf.
The fact that the British Isles were once part of the European mainland means that their rocks often resemble those of the closest parts of the continent. The ancient hard rocks of the Scottish Highlands, for example, such as granite, are similar to those of Scandinavia. Then there is the chalk of south-east England, seen in the white cliffs of Dover and across the Strait of Dover in northern France. The limestone ridge, or escarpment that crosses England from north-east to south-west also has its counterpart in northern France. And one more important example is the way in which the European Power Belt is continued into Britain.
From the Europeancontinent the British Isles are separated by the EnglishChannel and the North Sea. The English Channel, in its widest part in thewest is 220 km wide, andin the narrowest, what is called the Strait of Dover, only 32 km. The average depth of the Channel is 60 m, and thatof the Strait of Dover - 30 m. Herethe two opposite coasts of' England and France come so near, that on a clear day the cliffs of each side can be quite well seen from the opposite shore.
There were a number of schemes in the past how to connect the two coasts. Were Napoleaonalive today, he would be gratified that an idea he contemplated almost two centuries ago is to be translated into reality.
Despite the fact that the people in Kent, the south of England, were not enthusiastic about the venture as they feared damage to the environment, the old idea prevailed and major industrial and financial corporations swung into action. The final decision was made. Meeting at Lille, France, on January 20, 1986, the President of France and the Prime Minister of Great Britain chose one of the four projects which had been submitted.
This scheme, put forward by the Anglo—French Channel Tunnel - France Manche consortium, envisaged the construction of two rail tunnels 40 metres under the Channel bed. The tunnels are 7,3 metres in diameter and about 50 km long, of which 37 km are under the Channel. Cars, trucks and coachesdrive into specially built flat-cars and high-speed trains (160 km ph) leave every few minutes, reaching the terminal on the opposite side in 30 minutes.
In the west the British Islesare washed by theAtlantic Ocean, in the east - by the North Sea, the average depth of which is 95 m. The two largest islands of the British Archipelago, Great Britain and Ireland, are separated from each other by the Irish Sea and the two straits, the North Channel - 20 km wide, and St.George's Channel - over 100 km wide. The distance between the ports of Liverpool and Dublin is 230 km.
Apart from Britain the territories of six European countries look into the coasts of the North Sea - France, Belgium, the Netherlands, the Federative Republic of Germany, Denmark and Norway and for some of them this sea is theonly exit to the World Ocean. The most importantsea routes pass through the English Channel and the North Sea linking Europe with the Americas and other continents. The advantageous geographical position of Great Britain created favourable conditions for the development of her shipping, trade and the economy as a whole.
A place on the continental shelf has been of great advantage to the British fishing industry. Edible fish feed largely on plankton, the minute organism which abound in the shallow waters above the continental shelf, so that stretches ofwater such as the North Sea have long been rich fishing-grounds. Catches have been reduced by over-fishing, but other valuable resources have been discovered and exploited beneath the continental shelf - oil and natural gas.
The North Atlantic Current, the drift of warm water which reaches the islands from across the Atlantic, spreads out over the shelf magnifying its amiIiorating effect on the British Isles. This rather shallow skin of surface water, light because it is warm, is driven north-eastward across the ocean by the westerly winds. It forms part of the Gulf Stream system, which begins where Florida Current pours vast quantities of remarkably warm water into the circulation of the North Atlantic. In its journey across that ocean the water loses part of its heat, but retains enough to keep the ocean surface west of the British Isles warm in winter. During the winter months water which has been heated in far lower latitudes is arriving in the North Atlantic. Furthermore, the ocean surface becomes warmer or cooler, according to season, far more slowly than does a land surface in similar latitudes. The maximum surface temperature off the British coasts is reached in August; or even as late as September. Thus, when winter comes, there is much heat available to warm the air of the westerlies, and the seasonal fall of air temperature over Britain is sIow and slight.
The British Isles are known for their greatly indented coastline. Therefore there are many bays and harbours, peninsulas and capes on the coast, which were formed as a result of the raising and submerging of the land surface in the process of the geological development of the islands. The indentity pattern of the island of Great Britain greatly resembles that of the Norwegian coast abounding in numerous deep and winding, like rivers, fiords. Due to its extreme indentity the coastline of Great Britain despite its relatively modest size, is 8,000 km long.
Very much indented is the western coast, especially the coasts of Scotland and Wales. The highlands here rise quite abruptly from sea level, so that westward - flowing rivers are short end swift. Many long narrow lochs, or lakes, especially in the North-West Highlands, are finger lakes. Along the west coast are many inlets that are called lochs, such as Loch Fyne. These are sea lochs, or fiords: the ends of glaciated valleys which have been submerged by the sea.
The east coast is less lofty and more regular than the west coast, land sloping gradually down to the low sea shore and the coastal lowlands being flooded frequently.
Steep is the English coast of the Strait of Dover, where the chalk ridge comes right up to the sea repeating the chalk breakof the French coast on the other side of the English Channel.
The Irish coasts are more like those of England. The west coast is more indented with long rias and peninsulas, while the south coast conforms more with the general run of the relief. The east is relatively smooth with a few major estuaries in the north but it is only in the southeast; that lowland coasts with spite and bars blocking the estuaries are found. Cliffed coasts predominate here, and some are very beautiful.
The majority of the British ports have grown up at the mouths, wide estuaries of rivers which give sheltered water, deep enough to take the comparatively large ships. These sites are usually tidal and, from the eighteenth century onwards it became usual to construct dock basins which could be isolated from the sea or river by closing their gates. This meant that, as the tide ebbed and the water level in the estuary began to fall, the gates could by closed and the water level in the dock could be maintained at a high level, so that loading or unloading could continue regardless of the state of the tide. Many of the dock systems built during the nineteenth and early twentieth centuries became too small to handle the larger vessels afloat today and this resulted in the abandonment of old port areas and the building of new docks nearer the open sea, or even the constructions of entirely new ports, called outports. Apart from site, the most important factor in the growth of a port is its accessibility to a large and prosperous area of the country. Such an area, the area served by a port, is called the hinterland and it can vary in size from a few hundred square kilometres in the case of a small local port to virtually the whole of Britain in the case of London.
Of great importance for the portactivity are tides when the rising water reaches its maximum mark (high tide) of 6 m in the lower Thames (London), 8,5 a in the Mersey estuary (Liverpool), 10 m in the Bristol Channel (Cardiff) and 12 m at Bristol. Thanks to the high tides many of the towns which are situated dozens of kilometres from the coast (London-64, Glasgow - 55, Hull -32, and many others) have become sea ports.
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