Fjord
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A fjord or fiord (pronounced /fjɔːd/ or pronounced /fiːɔːd/) is a long, narrow inlet with steep sides, created in a valley carved by glacial activity.
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[edit] Formation
- Further information: Ice sheet dynamics#erosion
The seeds of a fjord are laid when a glacier cuts a U-shaped valley through abrasion of the surrounding bedrock by the sediment it carries. Many such valleys were formed during the recent ice age. Glacial melting is also accompanied by a rebound in the earth's crust as the ice load is removed. In some cases this rebound may be faster than the sea level rise. Most fjords are, however, deeper than the adjacent sea; Sognefjord, Norway, reaches as much as 1,300 m (4,265 ft) below sea level. Fjords generally have a sill or rise at their mouth caused by the previous glacier's terminal moraine, in many cases causing extreme currents and large saltwater rapids (along the Pacific Northwest Coast of North America (see skookumchuck). Saltstraumen in Norway is often described as the worlds strongest tidal current. These characteristics distinguish fjords from rias (e.g. the Bay of Kotor), which are drowned valleys flooded by the rising sea.
[edit] Fjord features and variations
[edit] Coral reefs
As late as 2000, some of the world's largest coral reefs were discovered along the bottoms of the Norwegian fjords. These reefs were found in fjords all the way from the north of Norway to the south. The marine life on the reefs is believed to be one of the most important reasons why the Norwegian coastline is such a generous fishing ground. Since this discovery is fairly new, little research has yet been done. So far, only the deep sea diver who discovered the first reef at 60 meters has visited it, and even he has only been down three times. The reefs are host to thousands of lifeforms such as plankton, coral, anemones, fish, several species of sharks, and many more one would expect to find on a reef. However most are specially adapted to life under the greater pressure of the water column above it, and the total darkness of the deep sea.
New Zealand's fiords are also host to deep sea corals, but a surface layer of dark fresh water allows these corals to grow in much shallower water than usual. An underwater observatory in Milford Sound allows tourists to view them without diving.
[edit] Skerries
In some places near the seaward margins of areas with fjords, the ice-scoured channels are so numerous and varied in direction that the rocky coast is divided into thousands of island blocks, some large & mountainous while others a merely rocky points or rock reefs, menacing navigation. These are called skerries. The term skerry is derived from the old Norse sker, which means a rock in the sea.
Skerries are most commonly formed at the outlet of fjords where submerged glacially formed valleys at right angles with the coast join with other cross valleys in a complex array. The island fringe of Norway is such a group of skerries (called a skjærgård); many of the cross fjords are so arranged that they parallel the coast and provide a protected channel behind an almost unbroken succession of mountainous islands and skerries. By this channel one can travel through a protected passage almost the entire 1,601.03 km route from Stavanger to North Cape, Norway. The Blindleia is a skerry-protected waterway that starts near Kristiansand in southern Norway, and continues past Lillesand. The Swedish coast along Bohuslän is likewise skerry guarded. The Inside Passage provides a similar route from Seattle, Washington and Vancouver, British Columbia to Skagway, Alaska. Yet another such skerry protected passage extends from the Straits of Magellan north for 800 km.
[edit] False fjords
The differences in usage between the English and the Scandinavian languages have contributed to confusion in the use of the term fjord. Bodies of water which are clearly fjords in Scandinavian languages are not considered fjords in English; similarly bodies of water which would clearly not be fjords in the Scandinavian sense have been named or suggested to be fjords. Examples of this confused usage follow.
The Gulf of Kotor in Montenegro has been suggested by some to be a fjord, but is in fact a drowned river canyon or ria. Similarly the Lim bay in Istria, Croatia, is sometimes called "Lim fjord" although it is not actually a fjord carved by glacial erosion but instead a ria dug by the river Pazinčica. The Croats call it Limski kanal which does not transliterate precisely to the English equivalent either.
Limfjord in the north of Denmark is a fjord in the Scandinavian sense, but is not a fjord in the English sense. In English it would be called a channel, since it separates the island of Vendsyssel-Thy from the rest of Jutland.
While the long fjord-like bays of the New England coast are sometimes referred to as "fiards", the only glacially-formed fjord-like feature in New England is Somes Sound in Maine.
The fjords in Finnmark (Norway), which are fjords in the Scandinavian sense of the term, are considered by some[who?] to be false fjords. Although glacially formed, most Finnmark fjords lack the classic hallmark steep-sided valleys of the more southerly Norwegian fjords since the glacial pack was deep enough to cover even the high grounds when they were formed.
In Mexico, the calanques - narrow, rocky inlets - on the western side of the city, where the famous cliff-divers perform daily, are dsecribed in the city's tourist literature as being fjords.
[edit] Freshwater fjords
Some Norwegian freshwater lakes which have formed in long glacially carved valleys with terminal moraines blocking the outlet follow the Norwegian naming convention; they are named fjords. Outside of Norway, the three western arms of New Zealand's Lake Te Anau are named North Fiord, Middle Fiord and South Fiord. Another freshwater "fjord" in a larger lake is Baie Fine, located on the northeastern coast of Georgian Bay of Lake Huron in Ontario. Western Brook Pond, in Newfoundland's Gros Morne National Park, is also often described as a fjord, but is actually a freshwater lake cut off from the sea, so is not a fjord in the English sense of the term. Such lakes are sometimes called "fjord lakes". Okanagan Lake was the first North American lake to be so described, in 1962.[1] The bedrock there has been eroded up to 650 m below sea level, which is 2000 m below the surrounding regional topography—deeper than the Grand Canyon.[2] Fjord lakes are common on the inland lea of the Coast Mountains and Cascade Range; notable ones include Lake Chelan, Seton Lake, Chilko Lake, and Atlin Lake. Kootenay Lake and others in the basin of the Columbia River are also fjord-like in nature, and created by glaciation in the same way. Along the British Columbia Coast, a notable fjord-lake is Owikeno Lake, which is a freshwater extension of Rivers Inlet. Another area notable for fjord lakes is northern Italy and southern Switzerland - Lago di Como and its neighbours.
[edit] Etymology
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With Indo European origin (*prtús from *por- or *per) in the verb fara (travelling/ferrying), the Norse noun substantive fjǫrðr means a "Lake-like" waterbody used for passage and ferrying.
The Scandinavian fjord, Proto-Scandinavian *ferþuz, is the origin for similar European words: Icelandic fjörður, Swedish fjärd (for Baltic waterbodies), Scottish firth. The Danish use fjord for any small bay or lagoon in their country. The Germans call the narrow long bays of Schleswig-Holstein Förde but the Norwegian bays Fjord. Perhaps the word is also related to English ford (which is in German Furt), Greek poros, Latin portus and the Dutch word voorde (for mud-flat, cf. Vilvoorde).
As a loanword from Norwegian, it is one of the few words in the English language to start with the digraph fj.
[edit] Scandinavian usage
Use of the word fjord (including the eastern Scandinavian form fjärd) is more general in the Scandinavian languages than in English. In Scandinavia, fjord is used for a narrow inlet of the sea in Norway, Denmark and western Sweden, but this is not its only application. In Norway, the usage is closest to the Old Norse, with fjord used for both a firth and for a long, narrow inlet. In eastern Norway, the term is also applied to long narrow freshwater lakes (for instance Mjøsa [commonly referred to as fjorden], Randsfjorden and Tyrifjorden) and sometimes even to rivers (in local usage, for instance in Flå in Hallingdal, the Hallingdal river is referred to as fjorden). In east Sweden, the name fjärd is used in a synonymous manner for bays, bights and narrow inlets on the Swedish Baltic Sea coast, and in most Swedish lakes. This latter term is also used for bodies of water off the coast of Finland where Finland Swedish is spoken. In Danish, the word may even apply to shallow lagoons. In modern Icelandic, fjörður is still used with the broader meaning of firth or inlet. In Finnish language, a word vuono is used although there is only one fjord in Finland.
The German use of the word Förde for long narrow bays on their Baltic Sea coastline, indicates a common Germanic origin of the word. The landscape consists mainly of moraine heaps. The "Förden" and some "fjords" on the east side of Denmark are also of glacial origin. But while the glaciers digging "real" fjords moved from the mountains to the sea, in Denmark and Germany they were tongues of a huge glacier covering the bassin of which is now the Baltic Sea. See Förden and East Jutland Fjorde.
Whereas fjordnames mostly describe bays (though not always geological fjords), straits in the same regions typically are named Sund, in Scandinavian languages as well as in German. The word is related to "to sunder" in the meaning of "to separate". So the use of Sound to name fjords in North America and New Zealand differs from the European meaning of that word.
The name of Wexford in Ireland is originally derived from Veisafjǫrðr ("inlet of the mud flats") in Old Norse, as used by the viking settlers — though the place does not have a fjord in the more narrow modern meaning.
[edit] Locations
The principal mountainous regions where fjords have formed are in the higher middle latitudes where, during the glacial period, many valley glaciers descended to the then-lower sea level. The fjords develop best in mountain ranges against which the prevailing westerly marine winds are orographically lifted over the mountainous regions, resulting in abundant snowfall to feed the glaciers. Hence coasts having the most pronounced fjords include the west coast of Europe, the west coast of North America from Puget Sound to Alaska, the west coast of New Zealand, and the west coast of South America. Other areas which have lower altitudes and less pronounced glaciers also have fjords or fjord-like features.
[edit] West coast of Europe
- Faroe Islands
- Norway
- Sweden, a small part of the west coast
- Iceland
- West Fjords (Vestfirðir)
[edit] West coast of New Zealand
- Fiordland, in the southwest of the South Island
[edit] Northwest Coast of North America
- The coast of Alaska in the United States:Lynn Canal, etc.
- British Columbia Coast, Canada: from the Alaskan Border along the Portland Canal to Indian Arm; Kingcome Inlet is a typical West Coast fjord.
- Hood Canal in Washington
[edit] West coast of South America
[edit] Other glaciated regions
Other regions have fjords, but many of these are less pronounced due to more limited exposure to westerly winds and less pronounced relief. Areas include:
- Europe
- Ireland (Ireland's only fjord is in Killary Harbour near Leenane, County Galway, on the west coast)
- Scotland (where called firths, the Scots language cognate of fjord; lochs or sea lochs)
- Sweden
- Galicia in Spain
- North America
- Canada:
- Newfoundland & Labrador: Saglek Fjord, Nachvak Fjord, Hebron Fjord, and Bonne Bay in Gros Morne National Park
- Quebec's Saguenay River valley
- the Canadian Arctic Archipelago, particularly:
- Greenland
- United States
- Somes Sound, Acadia National Park, Maine
- Hudson River
- most clearly seen at the New Jersey Palisades
- Canada:
- Antarctica
- Kerguelen Islands (France)
- particularly the Antarctic Peninsula
[edit] Extreme fjords
The longest fjords in the world are:
- Scoresby Sund in Greenland - 350 km (220 mi)
- Sognefjord in Norway - 203 km (126 mi)
- Hardangerfjord in Norway - 179 km (111 mi)
Deep fjords include:
- Skelton Inlet in Antarctica - 1,933 m (6,342 ft)
- Sognefjord in Norway - ~1,308 m (4,291 ft) (the mountains then rise to up to 1,000 m)
- Messier Channel in Chile, South America - 1,288 m (4,226 ft)
Even deeper is the Vanderford Valley (2,287 m or 7,503 ft), carved by the Antarctica's Vanderford Glacier. This undersea valley lies offshore, however, and so is not a fjord.
[edit] References
- ^ Nasmith, Hugh (1962), Late glacial history and surficial deposits of the Okanagan Valley, British Columbia, Victoria, BC, Canada: BC Ministry of Energy, Mines and Petroleum Resources
- ^ Eyles, Nicholas; Mullins, Henry T.; and Hine, Albert C. (1990). "Thick and fast: Sedimentation in a Pleistocene fiord lake of British Columbia, Canada". Geology 18 (11): 1153–1157. doi:.
[edit] See also
[edit] External links
- Use of whales to probe Arctic fjord's secrets
- Fjord guide at visitnorway.com - Official Travel Guide to Norway
- Pictures and info about Norwegian fjords
- More information about Norwegian fjords
- Fiordland's Marine Environment (and corals)
- Gallery of corals and associated marine life
- Saguenay River - The Canadian Atlas Online
