Cliff jumping

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]

Man jumping off cliff in Arizona.

Cliff jumping has inherent dangers due to the high velocity that can be attained during a long fall. Multiple cliff-jumping fatalities are reported every year.

In 2015 a world record for cliff jumping was set by Laso Schaller, with a jump of 58.8 m (193 ft).[4]

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.[5]

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.

Dangers
Cliff jumping as part of a coasteering adventure near Porthclais

In the UK between 2004 and 2008, tombstoning lead to 139 incidents in which a rescue or emergency response was required. Spinal injuries occurred with 20% of these, and 12 people died.[6]

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.[7][8]

Impact with water

Water resistance increase with the speed of entry, so a high-velocity dive induces rapid and potentially dangerous decelleration.[9] Jumping from a height of 20 feet (6.1 m) results in a person hitting the water at 25 mph (40 km/h), an impact strong enough to potentially result in temporary paralysis of the diagraphm,[9] a compressed spine, broken bones, or concussion.[10] Horizontal velocity attained from a running jump may also add to the impact speed.[11]

Fall height Velocity reached at water surface
5 feet (1.5 m) 12 mph (19 km/h)[9]
10 feet (3.0 m) 17 mph (27 km/h)[11]
20 feet (6.1 m) 25 mph (40 km/h)[10]
50 feet (15 m) 38 mph (61 km/h)[11]
85 feet (26 m) 53–62 mph (85–100 km/h)[11]

Cold water shock

A phenomenon known as cold water shock and can disrrupt the abilities of divers who enter very cold water[12]

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.[12] A too-shallow lakebed or seabed can also cause impact injury. In ocean conditions, tides can greatly affect water depth.[12]

Currents

As with any other water-based activity, strong currents can make timely exit from the water impossible.[6][13]

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[14]

See also

References
  1. LaViolette 2012, p. 79.
  2. "BBC News - Warning as Devil's Bridge 'tombstoning' continues despite death". Bbc.co.uk. 2013-07-10. Retrieved 2014-08-25.
  3. Williams & Micallef 2009, p. 222.
  4. Sampiero, Josh (18 August 2015). "This crazy guy set a new cliff-jump world record". Red Bull GmbH. Retrieved 7 September 2015.
  5. "Tombstoning - Torbay Council". Torbay.gov.uk. Archived from the original on 2011-06-04. Retrieved 2014-08-25.
  6. "Tombstoning – 'Don't jump into the unknown'". RoSPA. Archived from the original on 7 January 2022. Retrieved 15 March 2022.
  7. "Devon deaths warning over Plymouth Hoe tombstoning". BBC News. 18 June 2010.
  8. "'Unsafe' diving platform removed". BBC News. 17 February 2010.
  9. "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.
  10. Kolich, Heather (5 October 2009). "How Cliff Diving Works". how stuff works. p. 4. Archived from the original on 6 March 2022. Retrieved 15 March 2022.
  11. Kolich, Heather (5 October 2009). "How Cliff Diving Works". how stuff works. p. 2. Archived from the original on 6 March 2021. Retrieved 15 March 2022.
  12. 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.
  13. "Coasteering and Tombstoning". NWSF. Archived from the original on 10 May 2021. Retrieved 15 March 2022.
  14. "The Best Places In the World for Cliff Jumping". Shape. Retrieved 2020-12-11.
Sources

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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