Cliff jumping

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A person jumping off a cliff in Arizona.

Cliff jumping is the leaping off a cliff edge, usually into a body of water, as a form of sport. It may be done as part of the sport of coastal exploration[1] or as a standalone activity. Particular variations on cliff jumping may specify the angle of entry into the water or the inclusion or exclusion of human-made platforms or other equipment. Cliff diving and its close relative tombstoning are specific to water landing (with diving usually implying a head-first entry and tombstoning implying a feet-first entry).[2] Cliff jumping with the use of a parachute would typically be classified as a form of BASE jumping.[3]

Cliff jumping has inherent dangers due to the high velocity that can be attained during a long fall[4] and multiple cliff jumping deaths are reported every year.[4][5]

In 2015 a world record for cliff jumping was set by Laso Schaller, with a jump of 58.8 m (193 ft).[6]

In the Tomb of Hunting and Fishing there is a wall painting from around 530 - 500 BCE[7][8] [9][10] that shows a person climbing rocks towards a cliff face and a second person diving down the cliff face towards water.[11]

The Tomb of the Diver in Paestum, contains a fresco dating to around 470 BCE[11] that also shows a scene of a person diving into a pool or stream of water[12] from a structure.

Fresco. Tomb of Hunting and Fishing. Monterozzi necropolis, Tarquinia, Italy. Around 530 - 500 BCE
Fresco. Tomb of the Diver. Paestum, Italy. 470 BCE

Major variants

Tombstoning

Tombstoning is a form of cliff jumping popular in the United Kingdom characterized by upright vertical position of the body as it enters the water,[2] and the activity's name derives from a similarity between this posture and the form of a tombstone.[13]

Platform jumping

At alternative to a cliff as a launch point is a human-made platform. Jumping platforms may purpose built or improvised, but they may also be repurposed existing infrastructure such as a railway bridges.

Injuries and deaths

Cliff jumping as part of a coasteering adventure near Porthclais

In the UK between 2004 and 2008, cliff jumping lead to 139 incidents in which a rescue or emergency response was required. Spinal injuries occurred with 20% of these, and 12 people died.[4]In the UK between 2005 and 2015 there were 83 people injured and 20 people who died whilst cliff jumping.[14][5]

In recent years, injuries and deaths related to cliff jumping has increased calls for responses from local authorities and emergency services. A reaction to serious injuries and deaths at one popular tombstoning site, Plymouth Hoe, has led to the dismantling of seafront diving boards and closure of parts of the waterfront to discourage the activity.[15][16]

Dangers

Impact with water

Water resistance increases with the speed of entry, so entering the water at high-velocity induces rapid and potentially dangerous decelleration.[17][18] Jumping from a height of 20 feet (6.1 m) results in a person impacting with the water surface at 25 mph (40 km/h).[17] Impacting with the water surface at this velocity is capable of giving a person temporary paralysis of the diaphragm,[18] a compressed spine, broken bones, or concussion.[17]

Fall height Velocity reached at water surface
5 feet (1.5 m) 12 mph (19 km/h)[18]
10 feet (3.0 m) 17 mph (27 km/h)[17]
20 feet (6.1 m) 25 mph (40 km/h)[17]
50 feet (15 m) 38 mph (61 km/h)[17]
85 feet (26 m) 53–62 mph (85–100 km/h)[17]

Cold water shock

Cold water shock response occurs through the "rapid cooling of the skin and includes a gasp response followed by uncontrollable hyperventilation—obvious precursors to drowning." [19]

A person can die when they inspire into their lungs 22 ml of sea water per litre of body mass.[19] For a person weighing 70kg, death can occur when they inspire one and a half litres of sea water,[19] described as being "...one large inspiration."[19]

For fresh water the amount a person can die from when they inspire it is 44 ml per kg.[19] For a person weighing 70kg death can cocur from inspiring three litres of fresh water.[19]

It was also commented that "Cold water shock causes the blood vessels in the skin to close, which increases the resistance of blood flow. Heart rate is also increased. As a result the heart has to work harder and your blood pressure goes up."[20] Further that this "...rise in cardiac output and blood pressure can precipitate cardiovascular difficulties... [and] ...In such cases, survival time can be measured in seconds rather than hours."[19]

It has further been commented that "Cold water shock can therefore cause heart attacks, even in the relatively young and healthy."[20]

In relation to cold water shock and sea tempretures it has been commented that "Anything below 15°C is defined as cold water and can seriously affect your breathing and movement... Average UK and Ireland sea temperatures are just 12°C."[20][21]

In relation to the cold water chock response and the diffrences that occur across responses from people it has been commented that "In the 1950s, scientists examined why English Channel swimmers could spend 12–20 h swimming in 12–15°C water, while estimated survival time in these temperatures was in the region of 6 h." and that "...this unusual capability of outdoor swimmers to endure cold water has been attributed to large deposits of subcutaneous fat and a high level of physical fitness; however, these swimmers can also habituate themselves by repeated immersions in cold water." and that the "...cold shock response can be reduced by 50% in as few as six 2-min cold immersions..."[19] whilst the "Habituation of the shivering response needs longer immersions (>30 min)."[19]

Impact with submerged objects or terrain

Submerged objects also pose a direct risk to jumpers, who may sustain severe physical trauma upon colliding with them, or risk becoming entangled and unable to surface.[21] A too-shallow lakebed or seabed can also cause impact injury. In ocean conditions, tides can greatly affect water depth.[21]

Currents

As with any other water-based activity, strong currents can make timely exit from the water impossible.[4][22]

Popular cliff jumping locations

A jump off the cliffs of Guffey Gorge
  • Ponte Brolla, Switzerland
  • Playa Forti, Curaçao
  • Diving Board Island, Bermuda
  • South Point, Hawaii, United States
  • Negril, Jamaica
  • Possum Kingdom Lake, Texas, United States
  • Clarence Cove, Bermuda
  • Nusa Lembongan, Bali
  • Laie Point, Hawaii, United States
  • Amoudi Bay, Greece[23]

See also

References

  1. ^ LaViolette 2012, p. 79.
  2. ^ a b "BBC News - Warning as Devil's Bridge 'tombstoning' continues despite death". BBC. 2013-07-10. Archived from the original on 28 May 2017. Retrieved 24 May 2024.
  3. ^ Williams & Micallef 2009, p. 222.
  4. ^ a b c d "Tombstoning – 'Don't jump into the unknown'". RoSPA. Archived from the original on 7 January 2022. Retrieved 15 March 2022.
  5. ^ a b Thompson, George (26 July 2019). "The Port of Milford Haven warns against tombstoning". Western Telegraph. Archived from the original on 26 July 2019. Retrieved 15 March 2022.
  6. ^ Sampiero, Josh (18 August 2015). "This crazy guy set a new cliff-jump world record". Red Bull GmbH. Retrieved 7 September 2015.
  7. ^ Holloway, R. Ross (1965). "Conventions of Etruscan Painting in the Tomb of Hunting and Fishing at Tarquinii". American Journal of Archaeology. 69 (4): 341–347. JSTOR 502183.
  8. ^ Janson, Horst Woldemar; Janson, Anthony F. (2004). History of Art: The Western Tradition. Upper Saddle River, New Jersey: Prentice Hall. pp. 169–170. ISBN 978-0-13-182895-7.
  9. ^ S. Kleiner, Fred (2011). Gardner's Art Through the Ages: A Global History. Vol. 1. Boston, Massachusetts: Cengage Learning. p. 230. ISBN 978-1-4390-8578-3.
  10. ^ Steingräber, Stephan (2006). Abundance of Life: Etruscan Wall Painting. Los Angeles, California: Getty Publications. pp. 95–96. ISBN 978-0-89236-865-5.
  11. ^ a b Nathaniel S. Jones (2017). "Competitive Diving Principles and Injuries". Current Sports Medicine Reports. American College of Sports Medicine. Retrieved 30 May 2024.
  12. ^ Holloway, R. Ross (2006). "The Tomb of the Diver". American Journal of Archaeology. 110 (3): 371. doi:10.3764/aja.110.3.365. JSTOR 40024548.
  13. ^ "Tombstoning - Torbay Council". Torbay.gov.uk. Archived from the original on 2011-06-04. Retrieved 2014-08-25.
  14. ^ "Man dies after 'tombstoning' off Plymouth Hoe cliff". BBC. 14 October 2016. Archived from the original on 14 October 2016. Retrieved 15 March 2022.
  15. ^ "Devon deaths warning over Plymouth Hoe tombstoning". BBC News. 18 June 2010.
  16. ^ "'Unsafe' diving platform removed". BBC News. 17 February 2010.
  17. ^ a b c d e f g Kolich, Heather (5 October 2009). "How Cliff Diving Works". mapquest. Archived from the original on 24 May 2024. Retrieved 15 March 2022.
  18. ^ a b c "CLIFFS PLUS DIVING = DANGER: WATER, GRAVITY CAN TURN THRILLER INTO A KILLER". Deseret News. 8 June 1989. Archived from the original on 15 March 2022. Retrieved 15 March 2022.
  19. ^ a b c d e f g h i Tipton, Mike (December 2003). "Cold water immersion: sudden death and prolonged survival". The Lancet. Elsevier. Retrieved 29 May 2024.
  20. ^ a b c "Cold water shock". RNLI. Archived from the original on 24 May 2024. Retrieved 24 May 2024.
  21. ^ a b c Beresford, Alan (2 July 2020). "Tombstoning warning after Findochty Harbour incident". Grampian online. Archived from the original on 15 March 2022. Retrieved 15 March 2022.
  22. ^ "Coasteering and Tombstoning". NWSF. Archived from the original on 10 May 2021. Retrieved 15 March 2022.
  23. ^ "The Best Places In the World for Cliff Jumping". Shape. Retrieved 2020-12-11.
Sources

External links

Sources

  • LaViolette, Patrick (2012), "Risk, Rescue and Recreation", Extreme Landscapes of Leisure: Not a Hap-Hazardous Sport, Ashgate, ISBN 9781409488897
  • Williams, A. T.; Micallef, Anton (2009), Beach Management: Principles and Practice, Earthscan, ISBN 9781849770033
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