Pentland Firth
Pentland Firth | |
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Location in Scotland | |
Location | Scotland, UK |
Coordinates | 58°42′N 3°12′W / 58.7°N 3.2°W |
The Pentland Firth (
.Etymology
The name is presumed to be a corruption of the Old Norse "Petlandsfjörð",[1] meaning "the fjord of Pictland", and is completely unrelated to the Pentland Hills near Edinburgh.
Prior to the Norse occupation of Orkney the strait was known as the "Sea of Orcs" – a reference to the Pictish tribe who inhabited Orkney. Such was their marine prowess that there are also instances of this name referring to the sea lanes of the entire west coast of Scotland down to Kintyre. One version of the 9th-century Historia Brittonum states that "the Britons originally filled the whole island with their peoples from the English Channel to the Sea of Orcs".[2][3]
Geography
On the Caithness (southern) side the Firth extends from
In the middle of the Firth are two significant islands,
The most northerly point of the headland of Dunnet Head, Easter Head, is also that of mainland
Crossing the Firth
In the West the ferry from Scrabster to Stromness operated by NorthLink is the oldest continuous ferry service across the firth by the ferry MV Hamnavoe, started in 1856 as a continuation of the railhead at Thurso. The Far North Line opened 28 July 1874
Historically the Gills Bay area has been the main setting off point from the mainland to the islands of
At the eastern end John o' Groats Ferries sail to Burwick, also on South Ronaldsay. This is a small passenger ferry and is run in the summer months only.
Consideration was also given to construction of a tunnel linking the islands to the mainland. The 10-mile (16 km) tunnel was initially projected to have cost £100 million based on preliminary studies carried out in 2005 but as of 2012 no further progress has been made.
The first recorded swim across the Pentland Firth was by Coleen Blair in 2011. It has since been swum by others including Andrea Gellan (2011; fastest swim) Mark Cameron (2018) and Alison Lievesley (2020)
Tidal races
The Firth is well known for the strength of its tidal currents, which are among the fastest in the world, a speed of 30 kilometres per hour (16 kn) being reported close west of Pentland Skerries. The force of the tides gives rise to overfalls and tidal races which can occur at different stages of the tide. Combined with gale-force winds, they often give rise to extremely violent sea conditions, which have caused accidents such as the 2015 sinking of the cargo ship MV Cemfjord that resulted in the death of eight crew members.[8]
Some of the principal tidal races are:[9]
![](http://upload.wikimedia.org/wikipedia/commons/thumb/8/89/PentlandFirthMap.png/300px-PentlandFirthMap.png)
- ‘The Merry Men of Mey’. Forms off St John's point in the west-going stream and extends as the tide increases NNW across the firth to Tor Ness. The worst part is over a sand wave field about 5.5 kilometres (3.4 mi) west of Stroma. The waves formed by this race form a natural breakwater with relatively calm water to the east of it, particularly noticeable when a westerly swell is running. Tides in this area can exceed 19 km/h (10 kn).
- ‘The Swelkie’. The race at the north end of Stroma, off Swelkie Point is known as "The Swelkie". It extends from the point in an easterly or westerly direction depending on the tide and can be particularly violent. The Old Norse: Svalga, meaning "the Swallower".
- The ‘Duncansby Race’ forms off Ness of Duncansby at the start of the SE-going tidal stream (flood). Initially extending ENE but wheeling gradually anti-clockwise until it extends about 1.5 kilometres (0.93 mi) NW some 2+1⁄2 h later at which point it is known as ‘The Boars of Duncansby’. During the time of the SE stream there is additional turbulence off Duncansby Head, particularly to the East. The race temporarily ceases at the turn of the tide before forming in an ENE direction in the NW-going tidal stream (ebb) before ceasing again at the next turn of the tide. The race is particularly violent and dangerous when the tidal stream is opposed by gales in the opposite direction. During the east-going stream a race forms off Ness of Huna. This race can be particularly violent in an easterly or southeasterly gale.
- The ‘Liddel Eddy’ forms between South Ronaldsay and Muckle Skerry in the East-going stream (flood). A race also forms for part of the time off Old Head at the SE part of South Ronaldsay.
In addition to ‘The Swelkie’, races form at both the north and south ends of Stroma and Swona. Between the races there is a calm eddy which extends down tide as the tide strengthens. The races are highly visible with overfalls and whirlpools. Large swell waves can also be present, especially in bad weather conditions. When entering or leaving the eddies, crossing the races, even large powerful vessels can be pushed off course, such is the demarcation between the relatively calm eddy and the fast-moving tide in the races. There are other races in the firth particularly off Brough Head.
Tidal power
Currents of up to 5 metres per second (11 mph) make the Pentland Firth potentially one of the best sites in the world for
In October 2008 tidal power developer Atlantis Resources Corporation (ARC) announced it was considering a site near the
MeyGen completed the longest-ever run of continuous tidal electricity generation in 2019 with 25 GWh produced, enough to power nearly 4,000 homes.[21]
Marine wildlife
![Stroma Lighthouse, tower on the left, support buildings to the right, viewed from a distance across grassland, up muddy tracks](http://upload.wikimedia.org/wikipedia/commons/thumb/7/78/Stromalighthouse.jpg/220px-Stromalighthouse.jpg)
Porpoises can be seen all year round in all parts of the firth although they tend to favour shallower water. They grow to about 1.5 m and are black with a broad based triangular fin which can be seen as they surface. They have a small, rotund body with a short, blunt head, no beak, and a small, triangular dorsal fin. They are usually seen singly or in small numbers although in the autumn many groups may be seen in Gills Bay. When in groups, they tend to swim in a more random fashion than dolphins who swim together.
Dolphins are not very common but seen from time to time. Many different types visit the firth and may be seen anywhere at any time. Larger than porpoises, 2–3 m depending on the type, black, with the rear edge of the fin curved back at the top unlike the straight edge of the porpoise. Head has a distinct beak. Often swim alongside the bow of vessels and frolic in the bow waves. Probably more than one usually swimming together in a more synchronised manner, sometimes leaping out of the water.
See also
Notes
- ISBN 0-901824-25-9
- ^ Watson (1994) pp. 62–63
- Brythonic-speaking peoples.
- grid references for Dunnet Head: 58°40′21″N 03°22′31″W / 58.67250°N 3.37528°W, ND202767
- Stroma Lighthouse: 58°41′48″N 03°07′00″W / 58.69667°N 3.11667°W
- grid references for John o'Groats: ND379735
- ^ "Poor decision making led to the Cemfjord's capsizing". The International Institute of Marine Surveying (IIMS). 21 April 2016. Retrieved 27 May 2019.
- ISBN 978-90-79755-02-8
- ISBN 9780859915137.
- ISBN 0713429992.
- ^ a b Connor, Steve (10 July 2013). "Wave goodbye to hope of tidal energy exports, Scots politicians told". The Independent. Archived from the original on 25 May 2022.
- ^ Salter, Stephen; MacGregor, Kerr; Jones, Clifford (July 2006). "Scottish Energy Review: Scotland's opportunity – Scotland's challenge". Scottish National Party. Archived from the original (pdf) on 3 December 2006. Alt URL Archived 14 October 2013 at the Wayback Machine
- ^ a b Salmond, Alex (November 2006). "Small Country Thinks Big" (PDF). Scottish Renewables Review (32). Scottish Renewables. Archived from the original (PDF) on 26 March 2009.
- ^ "Salmond hails Pentland Firth Europe's powerhouse". The Scotsman. 29 September 2008.
- ^ Carrington, Damian (10 July 2013) "Tidal power from Pentland firth 'could provide half of Scotland's electricity' ". London: The Guardian.
- ^ "Major tidal power plan revealed" BBC News. Retrieved 26 October 2008.
- ^ Major Scottish tidal project unveiled New Civil Engineer, 28 October 2010. Retrieved: 4 November 2010.
- ^ "MeyGen secures consent for 86MW tidal energy project". MeyGen Ltd. 16 September 2013. Archived from the original on 14 October 2013. Retrieved 12 October 2013.
- ^ "Pentland Firth tidal turbine project given consent". BBC News. 16 September 2013.
- ^ Lewis, Michelle (4 February 2020). "EGEB: Tidal energy hit a major milestone in Scotland in 2019". Electrek. Retrieved 4 February 2020.
References
- Watson, W. J. (1994) The Celtic Place-Names of Scotland. Edinburgh; Birlinn. ISBN 1-84158-323-5. First published in Edinburgh; The Royal Celtic Society, 1926.
Further reading
- The available power from tidal stream turbines in the Pentland Firth 2013 Paper in Proc. R. Soc. Aby Adcock et al
External links
Media related to Pentland Firth at Wikimedia Commons
- Pentland Firth - Tides Archived 28 August 2006 at the Wayback Machine
- Tidal Diagrams