Celtic Sea

The Celtic SeaTemplate:Efn is the area of the Atlantic Ocean off the southern coast of Ireland bounded to the north by Saint George's Channel;<ref>C. Michael Hogan. 2011. Celtic Sea. eds. P. Saundry & C. Cleveland. Encyclopedia of Earth. National Council for Science and the /environment. Washington DC.</ref> other limits include the Bristol Channel, the English Channel, and the Bay of Biscay, as well as adjacent portions of Wales, Cornwall, parts of Devon and Brittany. The continental shelf, which drops away sharply, delimits the southern and western boundaries. The Iroise Sea off Brittany is entirely included within it. The Isles of Scilly are an archipelago of small islands in the sea.

History

The Celtic Sea receives its name from the Celtic heritage of the bounding lands to the north and east.<ref name="Haslam"> Template:Cite news</ref> E. W. L. Holt proposed the name at a 1921 meeting of fisheries experts from Great Britain, France, and the Republic of Ireland in Dublin.<ref name="Haslam" /> This sea's northern portion was considered part of Saint George's Channel, and the southern portion was an undifferentiated part of the "Southwest Approaches" to Great Britain. The desire for a common name came to be felt because of the area's common marine biology, geology and hydrology.<ref name="Haslam"/>

It was adopted in France before being common in English-speaking countries.<ref name="Haslam" /> In 1957, Édouard Le Danois wrote, "the name Celtic Sea is hardly known even to oceanographers."<ref name="Danois1957">Template:Cite book</ref> Marine biologists and oceanographers adopted it, and later, by petroleum exploration firms.<ref> Template:Cite news</ref> It is named in a 1963 British atlas,<ref>Template:Cite book; cited in
Template:Cite news</ref> but a 1972 article states, "what British maps call the Western Approaches, and what the oil industry calls the Celtic Sea [...] certainly the residents on the western coast [of Great Britain] don't refer to it as such."<ref> Template:Cite news </ref>

Seabed

The seabed under the Celtic Sea is referred to as the Celtic Shelf, part of the continental shelf of Europe. The northeast portion has a depth of between Template:Cvt, increasing towards Saint George's Channel. In the opposite direction, sand ridges pointing southwest have a similar height, separated by troughs approximately Template:Cvt deeper. These ridges were formed by tidal effects when the sea level was lower. South of 50°N, the topography is more irregular.<ref> Template:Cite book </ref>

Oil and gas exploration in the Celtic Sea has had limited commercial success. The Kinsale Head gas field supplied much of Ireland's demand for gas in the 1980s and 1990s. The water is too deep for fixed wind turbines. The area has potential for 50 GW of floating wind farms, and TotalEnergies plans a project with almost 100 MW.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Ecology

The Celtic Sea has a rich fishery with total annual catches of 1.8 million tonnes as of 2007.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Four cetacean species occur frequently: minke whale, bottlenose dolphin, short-beaked common dolphin and harbor porpoise.<ref>Template:Cite journal</ref> Formerly, it held an abundance of marine mammals.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref>

Limits

File:UK shipping forecast zones.png

Map of Sea Areas referred to in the Shipping Forecast; Lundy is in the Celtic Sea.

There are no land features to divide the Celtic Sea from the open Atlantic Ocean to the south and west. For these limits, Holt suggested the Template:Cvt marine contour and the island of Ushant off the tip of Brittany.

The definition approved in 1974 by the UK Hydrographer of the Navy for use in British Admiralty Charts was "bounded roughly by lines joining Ushant, Land's End, Hartland Point, Lundy Island, St. Govan's Head and Rosslare, thence following the Irish coast south to Mizen Head and then along the 200-metre isobath to approximately the latitude of Ushant."<ref> Template:Cite hansard </ref>

The International Hydrographic Organization defines the limits of the Celtic Sea as follows:<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

On the North. The Southern limit of the Irish Sea [a line joining St David's Head to Carnsore Point], the South coast of Ireland, thence from Mizen Head a line drawn to a position Template:Coord.

On the West and South. A line from the position Template:Coord South to 49°N, thence to latitude 46°30'N on the Western limit of the Bay of Biscay [a line joining Cape Ortegal to Penmarch Point], thence along that line to Penmarch Point.

On the East. The Western limit of the English Channel [a line joining Île Vierge to Land's End] and the Western limit of the Bristol Channel [a line joining Hartland Point to St. Govan's Head].

See also

• Irish Conservation Box

External links

• Coccoliths in the Celtic Sea  : a bloom of phytoplankton in the Celtic Sea, visible from outer space in an MISR image, 4 June 2001