Geografia del Regno Unito
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Il Regno Unito di Gran Bretagna e Irlanda del Nord è uno stato dell'Europa occidentale. Comprende l'isola della Gran Bretagna (Inghilterra, Scozia e Galles) e la sesta parte settentrionale dell'isola dell'Irlanda (l'Irlanda del Nord), insieme a molte altre isole minori. Il Paese sorge tra le latitudini 49°N e 59°N (le Isole Shetland arrivano anche a 61°N), e alle longiduini da 8°W a 2°E. L'Osservatorio Reale di Greenwich, presso Londra, è il punto di riferimento per il Meridiano di Greenwich. Il Regno Unito, nell'insieme, copre un'area di circa 245.000 km².
Il Regno Unito sorge tra l'Oceano Atlantico settentrionale e il Mare del Nord, e giunge fino a 35 km dalla costa nord-occidentale della Francia, dalla quale è separata dal Canale della Manica. L'Irlanda del Nord ha un confine di circa 360 km con la Repubblica d'Irlanda. Il Tunnel della Manica ("Chunnel"), scavato al di sotto del Canale della Manica, collega il Regno Unito con la Francia.
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[modifica] Geografia fisica
La geografia fisica del Regno Unito varia vistosamente. Comprende le scogliere di gesso del Kent e del Dorset, le colline e le pianure dell'Inghilterra sud-orientale, le scogliere di granito della Cornovaglia, le montagne del Galles, i rilievi del Peak District e le Pennine, i laghi e le montagne della Cumbria, le pianure e le isole della Scozia, i campi, i laghi e le montagne dell'Irlanda del Nord.
La geomorfologia del Regno Unito è stata formata dalle forze combinate della tettonica e dei cambiamenti climatici, in particolare delle glaciazioni.
Il centro esatto dell'isola della Gran Bretagna è molto discusso: a seconda di come è calcolato, può trovarsi o a Haltwhistle nel Northumberland, o presso Dunsop Bridge nel Lancashire.
[modifica] Geologia
La geologia del Regno Unito è varia e complessa, e pertanto fornisce una grande varietà di paesaggi che si possono trovare nel Paese. This variety, coupled with the early efforts of UK based scientists and geologists to understand it, has influenced the naming of many geological concepts, including many of the geological periods (for example, the Ordovician period is named after the Ordovices, a people of early Britain; the Devonian period is named after the county of Devon in south-west England).
The oldest rocks in the UK are gneisses which date from at least 2,700 Ma ("Ma" means "millions of years ago") in the Archaean Period, which are found in the far north west of Scotland and in the Hebrides, with a few small outcrops elsewhere. South of the gneisses are a complex mixture of rocks forming the North West Highlands and Grampian Highlands in Scotland, as well as the Connemara, Donegal and Mayo mountains of north Ireland. These are essentially the remains of folded sedimentary rock, deposited over the gneiss, from 1,000 Ma, with a notable 7 km thick layer of Torridon Sandstone being deposited about 800 Ma, as well as the debris deposited by an ice sheet 670 Ma.
The remains of ancient volcanic islands underlie much of central England with small outcrops visible in many places. Around 600 Ma, the Cadomian Orogeny (mountain building period) caused the English and Welsh landscape to be transformed into a mountainous region, along with much of north west Europe.
The Welsh Skiddaw slate deposits formed at around 500 Ma, during the Ordovician Period. At about this time, around 425 Ma, north Wales (and south Mayo in Ireland) experienced volcanic activity. The remains of these volcanoes are still visible, for example Rhobell Fwar, dating from 510 Ma. Large quantities of volcanic lava and ash known as the Borrowdale Volcanics covered both Wales and the Lake District, still seen in the form of mountains such as Helvellyn and Scafell Pike.
In the Silurian Period, between 425 and 400 Ma, the Caledonian fold mountains formed (the Caledonian Orogeny), covering much of what is now the UK to perhaps 8,000 feet (2,500 m) thick. Volcanic ashes and lavas deposited during this period are still found in the Mendip Hills and in Pembrokeshire.
Volcanic deposits formed Ben Nevis in the Devonian Period. Sea levels varied considerably, with the coastline advancing and retreating from north to south across England, and with the deposition of numerous sedimentary rock layers. The Old Red Sandstone of Devon gave the period its name, though deposits are found in many other places.
During the Carboniferous Period, around 360 Ma, the UK was lying at the equator, covered by the warm shallow waters of the Rheic Ocean, during which time the Carboniferous limestone was deposited, still found in areas such as the Mendip Hills and the Pennines. The coal measures were formed at this time, in river deltas, swamps and rain forests. Coal can be found in many areas of the UK, as far North as Sutherland and as far south as Kent, though it has largely been mined in the Midlands, northern England and Wales. Also formed were the Millstone Grits.
During the Permian and Triassic Periods, much of the UK was beneath shallow seas, leading to the deposition of sedimentary rocks such as shale, limestone, gravel, and marl. The seas finally receded to leave a flat desert with salt pans.
At the beginning of the Jurassic Period, the UK was under-water again, leading to the deposition of sedimentary rocks which now underlie much of England from the Cleveland Hills of Yorkshire to the Jurassic Coast in Dorset, including clays, sandstones, and the oolitic limestone of the Cotswold Hills. The burial of algae and bacteria below the mud of the sea floor during this time resulted in the formation of North Sea oil and natural gas.
In the Cretaceous Period, much of the UK was again below the sea and chalk and flints were deposited over much of Great Britain. These are now notably exposed at the White Cliffs of Dover, and form Salisbury Plain, the Chiltern Hills, the South Downs and other similar features.
The last volcanic rocks in the UK were formed in the early Tertiary Period, between 63 and 52 Ma, with the major eruptions that formed the Antrim Plateau and the basaltic columns of the Giant's Causeway. Further sediments were deposited over southern England, including the London clay, while the English Channel consisted of mud flats and river deposited sands.
The major changes during the last few million years, during the Quaternary Period, have been brought about by several recent ice ages, leaving a legacy of U-shaped valleys in highland areas, and fertile (if often stoney) soil in southern England.
[modifica] Montagne e colline
Le dieci più alte montagne del Regno Unito si trovano in Scozia. Le più alte cime del Regno Unito sono:
- Scozia: Ben Nevis (Catena Nevis, 1.344 metri)
- Galles: Snowdon (Monti della Cambria, 1.085 metri)
- Inghilterra: Scafell Pike (Monti della Cumbria, 977 metri)
- Irlanda del Nord: Slieve Donard (Monti Mourne, 852 metri)
Le principali colline del regno unito sono: Scozia: Cairngorms, Cheviot Hills, Scottish Highlands, Southern Uplands, Grampian Mountains Galles: Brecon Beacons, Cambrian Mountains, Snowdonia, Black Mountains, Preseli Hills Inghilterra: Chilterns, Cotswolds, Dartmoor, Exmoor, Lake District, Malvern Hills, Mendip Hills, North Downs, Peak District, Pennines, Salisbury Plain, South Downs, Shropshire Hills: Irlanda del nord Mountains of Mourne, Antrim Plateau, Sperrin Mountains
[modifica] Fiumi e laghi
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Per approfondire, vedi la voce Distribuzione delle risorse idriche. |
- Main articles
- List of lakes in the United Kingdom;
- Rivers of the United Kingdom;
- Waterfalls of the United Kingdom.
c. The longest river in the UK is the River Severn (220 miles, 354 km) which flows through both Wales and England.
The longest rivers in the UK are:
- England: River Thames (215 miles, 346 km)
- Scotland: River Tay (117 miles, 188 km)
- N. Ireland: River Bann (76 miles, 122 km)
- Wales: River Tywi (64 miles, 103 km)
The largest lakes in the UK are:
- N. Ireland: Lough Neagh (147.39 sq mi, 381.74 km²)
- Scotland: Loch Lomond (27.46 sq mi, 71.12 km²)
- England: Windermere (5.69 sq mi, 14.74 km²)
- Wales: Lake Vyrnwy (3.18 sq mi, 8.24 km²)
The deepest lake in the UK is Loch Morar with a maximum depth of 309 metres (Loch Ness is second at 228 metres deep). The deepest lake in England is Wastwater which descends to 79 metres (258 feet).
[modifica] Vie d'acqua
Main articles: Waterways in the United Kingdom, Canals of the United Kingdom, Reservoirs and dams in the United Kingdom
As a result of its industrial history, the United Kingdom has an extensive system of canals, mostly built in the early years of the Industrial Revolution, before the rise of competition from the railways. The United Kingdom also has numerous dams and reservoirs to store water for drinking and industry. The generation of hydroelectric power is rather limited, supplying less than 2% of British electricity mainly from the Scottish Highlands.
[modifica] Costa
The UK has a coastline which measures approximately 12,429 km (although this is a somewhat arbitrary figure since, being a fractal, the length of the coastline will increase as the unit with which is it measured decreases). The heavy indentation of the coastline helps to ensure that no location is more than 125 km from tidal waters.
The UK claims jurisdiction over the continental shelf, as defined in continental shelf orders or in accordance with agreed upon boundaries, an exclusive fishing zone of 200 n. miles (370 km), and territorial sea of 12 n. miles (22 km).
[modifica] Insenature
- Cardigan Bay
- Lyme Bay
- Bristol Channel
- Thames estuary
- Morecambe Bay
- Solway Firth
- The Wash
- Humber estuary
- Firth of Forth
- Firth of Tay
- Moray Firth
[modifica] Promontori
The geology of the UK is such that there are many headlands along its coast, here are some of the most notable ones:
- Cornwall
- Lands End
- The Lizard
- Cape Cornwall
- Cumbria
- Furness
- Devon
- Start Point
- Berry Head
- Hartland Point
- Dorset
- Old Harry Rocks
- St Alban's Head
- Portland Bill
- St Abb's Head
- West Sussex
- Selsey Bill
- East Sussex
- Beachy Head
- Kent
- North Foreland
- Sutherland
- Cape Wrath
- Swansea
- Gower Peninsula
- Wigtownshire
- Rhins of Galloway
- Yorkshire
- Filey Brig
- Flamborough Head
- Spurn Head
[modifica] Coastal change
[modifica] Isole
In total, it is estimated that the UK is made up of over 1000 small islands, some being natural and some being man-made crannogs, which were built in past times using stone and wood and which were enlarged by natural waste building up over time.
- Islands of England
- Lundy
- Isles of Scilly
- Isle of Wight
- Farne Islands
- Lindisfarne
- Isle of Portland
- Walney Island
- Islands of Scotland
- Orkney Islands
- Shetland Islands
- Inner Hebrides
- Outer Hebrides
- Rockall
- Bass Rock
- Fair Isle
- Islands of Wales
- Anglesey
- Skomer Island
- Skokholm Island
- Ramsey Island
- Bardsey Island
- Holy Island
- Islands of Northern Ireland
[modifica] Clima
The climate of the UK varies, but is generally temperate, though significantly warmer than some other locations at similar latitude, such as central Poland, due to the warming influence of the Gulf Stream. In general, the south is warmer and drier than the north.
The prevailing winds are southwesterly, from the North Atlantic Current. More than 50% of the days are overcast. There are few natural hazards, although there can be strong winds and floods, especially in winter.
Average annual rainfall varies from over 3,000 mm (120 inches) in the Scottish Highlands down to 553 mm (21.8 inches) in Cambridge. The county of Essex is one of the driest in the UK, with an average annual rainfall of around 600 mm (24 inches), although it typically rains on over 100 days per year. In some years rainfall in Essex can be below 450 mm (18 inches), less than the average annual rainfall in Jerusalem and Beirut.
The highest temperature recorded in the UK was 38.5 °C at Brogdale, near Faversham, in the county of Kent, on August 10, 2003. The lowest was -27.2 °C recorded at Braemar in the Grampian Mountains, Scotland, on February 11, 1895 and January 10, 1982 and Altnaharra, also in Scotland, on December 30, 1995.
[modifica] Geografia umana
[modifica] Demographics
Main article: Demographics of the United Kingdom
[modifica] Political geography
Main article: Politics of the United Kingdom
[modifica] National government
The UK is governed as a whole by the Parliament of the United Kingdom.
The UK is divided into four areas: England, Northern Ireland, Scotland and Wales. Each of these has its own brand of government:
- Northern Ireland - Northern Ireland Assembly (suspended but currently meeting as a "Virtual Assembly")
- Scotland - Scottish Parliament
- Wales - Welsh Assembly
- England - None overall - the current Labour government has stated that it believes England too large to host a single Assembly. Proposals for elected Regional Assemblies in England seem unlikely to progress in the short term following the rejection of an Assembly for the North East England in a referendum. See Government of England.
The UK (specifically, Northern Ireland) has an international land boundary with the Republic of Ireland of 360 km. There is also a boundary between the jurisdiction of France and of the UK on the Channel Tunnel.
[modifica] Local government
Main article: Local government of the United Kingdom
Each part of the UK is subdivided in further local governmental regions:
- England: Unitary Authorities, county councils, district councils, parish councils
- Wales: Principal areas, communities
- Scotland: Council areas, communities
- Northern Ireland: Districts
Historically the UK was divided into traditional counties or shires: administrative areas through which all civil responsibilities of the government were passed. There are eighty six traditional counties across the whole of the UK. Each county or shire had a county town as its administrative centre and was divided into individual parishes that were defined along ecclesiastic boundaries.
Between 1889 (1890 in Scotland) and 1974, the political boundaries were based on the traditional counties, but due to changes in population centres, the traditional counties became impractical as local government areas in certain highly urbanised areas. The Local Government Act 1972 created a new system of administrative counties, designed to take account of the widely differing populations across different parts of the country.
In the 1990s further population growth led to more political changes on a local level. Unitary authorities were formed across the entire of Scotland and Wales, and in larger cities in England. Many unpopular administrative counties were also abolished at this time, leading to a mixture of two-tier and single-purpose authorities. Further reorganisations are planned if and when regional assemblies in England are revisited in the future.
[modifica] Economic geography
Main article: Economic geography of the United Kingdom
The economic geography of the UK reflects not only its current position in the global economy, but its long history both as a trading nation and an imperial power.
The UK led the industrial revolution and its highly urban character is a legacy of this, with all its major cities being current or former centres of all forms of manufacturing. However, this in turn was built on its exploitation of natural resources, especially coal and iron ore.
[modifica] Primary industry
The UK's primary industry was once dominated by the coal industry, heavily concentrated in the north, the Midlands and south Wales. This is all but gone and the major primary industry is North Sea oil. Its activity is concentrated on the UK Continental Shelf to the north-east of Scotland.
[modifica] Manufacturing
At one time or another virtually every product that can be imagined has been made in the UK. In particular its heavy manufacturing drove the industrial revolution. A map of the major UK cities gives a good picture of where this activity occurred, in particular Belfast, Birmingham, Glasgow, London, Manchester, Newcastle, Nottingham.
Today there is no heavy manufacturing industry in which UK-based firms can be considered world leaders. However, the Midlands in particular remains a strong manufacturing centre.
More recently, high technology firms have concentrated largely along the M4 motorway, partly because of access to Heathrow Airport, but also because of agglomeration economies.
[modifica] Finance and services
Once, every great city had a stock exchange. Now, the UK financial industry is concentrated overwhelmingly in the City of London and Canary Wharf, with back office and administrative operations often dispersed around the south of England. London is one of the world's great financial centres and is usually referred to as a world city.
[modifica] Regional disparity
The combined effect of changing economic fortune has created the so-called North-South divide, in which decaying industrial areas of the north of England contrast with the wealthy, finance and technology led southern economy.
This has led successive governments to develop regional policy to try and rectify the imbalance.
This is not to say that the south is uniformly wealthy: some of the worst pockets of deprivation can be found in London, especially east London.
[modifica] Natural resources
Main article: Economy of the United Kingdom
Historically, much of the United Kingdom was forested. Since prehistoric times, man has deforested much of the United Kingdom.
Agriculture is intensive, highly mechanised, and efficient by European standards, producing about 60% of food needs with only 1% of the labour force. It contributes around 2% of GDP. Around two thirds of production is devoted to livestock, one third to arable crops.
In 1993, it was estimated that land use was:
- Arable land: 25 %
- Permanent crops: 0 %
- Permanent pastures: 46 %
- Forests and Woodland: 12 %
- Other: 17 %
- Irrigated: 1,080 km²
The UK has a variety of natural resources including:
- Geological: coal, petroleum, natural gas, limestone, chalk, gypsum,silica, rock salt, china clay, iron ore, tin, silver, gold, lead.
- Agricultural: arable land, wheat, barley, hill farms, sheep
The UK has large coal, natural gas, and oil reserves; primary energy production accounts for 10% of GDP, one of the highest shares of any industrial nation. Due to the island location of the UK, the country has great potential for generating electricity from wave power and tidal power, although these have not yet been exploited on a commercial basis.
[modifica] Environment
[modifica] Current issues
The United Kingdom is reducing greenhouse gas emissions. It has met Kyoto Protocol target of a 12.5 % reduction from 1990 levels and intends to meet the legally binding target of a 20 % cut in emissions by 2010. By 2005, the government aims to reduce the amount of industrial and commercial waste disposed of in landfill sites to 85 % of 1998 levels and to recycle or compost at least 25 % of household waste, increasing to 33 % by 2015. Between 1998-99 and 1999-2000, household recycling increased from 8.8 % to 10.3 %.
[modifica] International agreements
The United Kingdom is a party to many international agreements, including: Air Pollution, Air Pollution-Nitrogen Oxides, Air Pollution-Sulphur 94, Air Pollution-Volatile Organic Compounds, Antarctic-Environmental Protocol, Antarctic-Marine Living Resources, Antarctic Seals, Antarctic Treaty, Biodiversity, Climate Change, Climate Change-Kyoto Protocol, Desertification, Endangered Species, Environmental Modification, Hazardous Wastes, Law of the Sea, Marine Dumping, Marine Life Conservation, Nuclear Test Ban, Ozone Layer Protection, Ship Pollution, Tropical Timber 83, Tropical Timber 94, Wetlands and Whaling.
The UK has signed, but not ratified, the international agreement on Air Pollution-Persistent Organic Pollutants.
[modifica] See also
- British overseas territories
- Conservation in the United Kingdom
- Demographics of the United Kingdom
- Extreme points of the United Kingdom
- Geography of Scotland
- Geography of Ireland
- Geography of Europe
- List of caves in the United Kingdom
- List of places in the United Kingdom
- List of United Kingdom-related topics
- List of conurbations in the United Kingdom
- City status in the United Kingdom
- Towns of the United Kingdom
- Transport in the United Kingdom
- Category:Geography of the United Kingdom
