Fjord

Fjord

A fjord or fiord (pronEng|fjɔːd|fiːɔːd or pronEng|fiːɔːd) is a long, narrow inlet with steep sides, created in a valley carved by glacial activity.

Formation

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 convert|1300|m|abbr=on|0 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.

Fjord features and variations

Coral reefs

As late as 2000, some of the world's largest coral reefs were discovered along the bottoms of the Norwegian fjords.Fact|date=September 2008 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 convert|60|m|abbr=on 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.

kerries

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 and mountainous while others are 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 perpendicular to 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 convert|1601|km|abbr=on|0 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 convert|800|km|abbr=on.

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 Bay 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 North Jutlandic Island (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 someWho|date=August 2007 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 described in the city's tourist literature as being fjords.

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. [Citation |last=Nasmith |first=Hugh |year =1962 |title =Late glacial history and surficial deposits of the Okanagan Valley, British Columbia |place=Victoria, BC, Canada |publisher=BC Ministry of Energy, Mines and Petroleum Resources ] The bedrock there has been eroded up to convert|650|m|abbr=on|0 "below" sea level, which is convert|2000|m|abbr=on|0 below the surrounding regional topography—deeper than the Grand Canyon. [cite journal |last=Eyles |first=Nicholas |coauthors=Mullins, Henry T.; and Hine, Albert C. |year=1990 |title=Thick and fast: Sedimentation in a Pleistocene fiord lake of British Columbia, Canada |journal=Geology |volume=18 |issue=11 |pages=1153–1157 |doi=10.1130/0091-7613(1990)018<1153:TAFSIA>2.3.CO;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 - Lake Como and its neighbours.

Etymology

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 mudflat, cf. Vilvoorde).

As a loanword from Norwegian, it is one of the few words in the English language to start with the digraph "fj".

candinavian 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 the 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.

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.

Principal glaciated regions

* West coast of Europe
**Faroe Islands
**West Fjords (Westfjords [Vestfirðir] ) of Iceland
** Lofoten, Svalbard and Spitsbergen in Norway
**Kola Bay in Russia
[
Eyjafjörður in north Iceland, Akureyri can be seen to the far right]
*West coast of New Zealand
**Fiordland, in the southwest of the South Island

*Northwest Coast of North America
**The coast of Alaska, 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, United States
*West coast of South America
**Zona Austral, Chile

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
** Galicia in Spain
** Ireland (Ireland's only fjord is in Killary Harbour near Leenaun, County Galway, on the west coast)
** Scotland (where called firths, the Scots language cognate of fjord; lochs or sea lochs)
** the Gullmaren on the west coast of Sweden

*North America
** Canada:
*** Newfoundland and 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:
****Ellesmere Island
****Baffin Island
** Greenland
** United States
***Somes Sound, Acadia National Park, Maine
***Hudson River
****most clearly seen at the New Jersey Palisades

*Arctic
**Arctic islands

*Antarctica
**Kerguelen Islands (France)
**particularly the Antarctic Peninsula

*Sub-antarctic islands

Extreme fjords

The longest fjords in the world are:
# Scoresby Sund in Greenland - convert|350|km|abbr=on|0
# Sognefjord in Norway - convert|203|km|abbr=on|0
# Hardangerfjord in Norway - convert|179|km|abbr=on|0

Deep fjords include:
# Skelton Inlet in Antarctica - convert|1933|m|abbr=on|0
# Sognefjord in Norway - convert|1308|m|abbr=on|0 (the mountains then rise to up to convert|1000|m|abbr=on|0)
# Messier Channel in Chile - convert|1288|m|abbr=on|0

Even deeper is the Vanderford Valley (convert|2287|m|abbr=on|0), carved by Antarctica's Vanderford Glacier. This undersea valley lies offshore, however, and so is not a fjord.

References

External links

* [http://news.bbc.co.uk/1/hi/sci/tech/2683797.stm Use of whales to probe Arctic fjord's secrets]
* [http://www.visitnorway.com/MWTemplates/QWFeature.aspx?id=175771 Fjord guide at visitnorway.com - Official Travel Guide to Norway]
* [http://www.fjords.com Pictures and info about Norwegian fjords]
* [http://www.doc.govt.nz/templates/podcover.aspx?id=33897 Fiordland's Marine Reserves]
* [http://www.milforddeep.co.nz/gallery.htm Gallery of corals and associated marine life at Milford Sound]
* [http://www.canadiangeographic.ca/atlas/themes.aspx?id=rivers&sub=rivers_east_saguenay Saguenay River - The Canadian Atlas Online]


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Look at other dictionaries:

  • fjord — fjord …   Dictionnaire des rimes

  • fjord — [ fjɔr(d) ] n. m. VAR. fiord • 1795; mot norv. ♦ Ancienne vallée glaciaire envahie par les eaux marines durant la déglaciation, caractéristique des côtes scandinaves et écossaises. Les fjords de Norvège. « comme une flamme liquide et bleue, le… …   Encyclopédie Universelle

  • Fjord — (fy[^o]rd), n. See {Fiord}. [1913 Webster] …   The Collaborative International Dictionary of English

  • Fjord — der; [e]s, e <aus gleichbed. schwed., norw. fjord> [an einer Steilküste] tief ins Landesinnere hineinreichender, lang gestreckter Meeresarm …   Das große Fremdwörterbuch

  • fjord — fjord; fjord·ed; …   English syllables

  • Fjord — Fjord: Die skand. Bezeichnung der schmalen, felsigen Meeresbucht (schwed., norw. fjord, aisl. fjo̧rđr), die ablautend mit ↑ Furt verwandt ist, wurde Ende des 19. Jh.s ins Dt. entlehnt. Auch gleichbed. engl. firth stammt aus dem Nord …   Das Herkunftswörterbuch

  • fjord — sb., en, e, ene, i sms. fjord , fx fjordfiskeri, fjordvand …   Dansk ordbog

  • Fjord — (dän.), so v.w. Meerbusen …   Pierer's Universal-Lexikon

  • Fjord — (dän.), schmaler, trogförmiger, tiefer, tief ins Land eingreifender, meist gewundener, nach oben sich verzweigender Meerbusen mit steilen Wänden. [Tafel: Kartographie II, 10.] …   Kleines Konversations-Lexikon

  • Fjord — Fjord, in den skandinav. Sprachen Meerbusen …   Herders Conversations-Lexikon

  • Fjord — Fjord,der:⇨1Bucht(1) FjordMeeresbucht,Meeresarm,Meeresbusen,Bai,Bucht,Golf,Förde …   Das Wörterbuch der Synonyme

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