Mount Ngauruhoe is an active stratovolcano in New Zealand, made from layers of lava and tephra. It is the youngest vent in the Tongariro volcanic complex on the Central Plateau of the North Island, and first erupted about 2,500 years ago. Although often regarded as a separate mountain, geologically it is a secondary cone of Mount Tongariro.
Ngauruhoe seen from Mount Tongariro
|Elevation||2,291 m (7,516 ft)|
|Location||North Island, New Zealand|
|Mountain type||Stratovolcano (active)|
|Volcanic arc/belt||Taupo Volcanic Zone|
|First ascent||March 1839 by John C. Bidwill, an English botanist. Two Māori guides came with him to within 1 kilometre of the peak.|
|Easiest route||Scramble (summer)|
The volcano lies between the active volcanoes of Mount Tongariro to the north and Mount Ruapehu to the south, to the west of the Rangipo Desert and 25 kilometres to the south of the southern shore of Lake Taupo.
The local Māori traditions state that the volcano was named by Ngātoro-i-rangi, an ancestor of the local Māori iwi, Ngāti Tūwharetoa. Ngātoro-i-rangi called volcanic fire from his homeland Hawaiki, which eventually emerged at Ngauruhoe. The name given by Ngātoro-i-rangi (Ngauruhoe) either commemorates his slave, who had died from the cold before the fire arrived, or refers to the insertions (ngā uru) of Ngātoro-i-rangi's hoe (paddle-like staff) into the ground during his summoning of the volcanic fire.
Ngauruhoe erupted 45 times in the 20th century, most recently in 1977. Fumaroles exist inside the inner crater and on the rim of the eastern, outer crater. Climbers who suffer from asthma may be affected by the strong sulphurous gases emitted from the crater.
A significant increase in earthquake activity in May 2006 prompted the alert level to be raised from zero (typical background activity, no signs of significant unrest) to one (signs of volcano unrest). Over the next two years GeoNet recorded an average of 5 to 30 earthquakes a day close to Ngauruhoe, though the maximum daily number was as high as 80.
After mid-2008, the number of volcanic earthquakes close to Ngauruhoe declined to the background level. Regular measurements of volcanic gas levels and the temperature of a summit gas vent failed to record any significant changes over the subsequent two and a half years. GNS Science accordingly reduced the alert level for Ngauruhoe to Level 0 on 2 December 2008. “The reduction in earthquake activity means that an eruption in the near future is unlikely without further earthquakes or other changes and the appropriate alert level is therefore zero”, said GNS Science Volcano Section Manager Gill Jolly.
An increase in seismic activity in March 2015 resulted in the alert level being raised to Level 1. The anomalous activity was deemed to have subsided after three weeks, and the alert level was lowered back to Level 0.
The mountain is usually climbed from the western side, from the Mangatepopo track. In summer the climb is difficult due to the loose tephra that gives way underfoot. In the summer of 2010 a climber was seriously injured by falling rock. In winter, snow consolidates the tephra. After rain, the snow may be covered by ice which is treacherous. Ice axes, crampons and ropes are recommended in midwinter. Between March and October the mountain is subject to sudden violent wind gusts and snow storms with the temperature plunging well below zero.
There is also a route from the northern side which cuts across the lava flows in the Mangatepopo valley from the Mangatepopo hut. This route is far longer with no flat areas. On reaching the summit, climbers can circumnavigate the crater and descend the normal eastern route.
During the closure of the central part of the Mt. Tongariro one day walk, due to volcanic activity, climbing Mt. Ngauruhoe became a popular alternative. At Easter 2013 four climbers were injured in separate incidents. Two of the accidents were due to congestion on the normal eastern route to the crater when a climber caused loose rock to hit another climber below. All the injured had to be rescued by helicopter.
In 1974, as part of a promotional campaign for his sponsor Moët & Chandon, champion skier Jean-Claude Killy was filmed skiing down the previously unskied eastern slope of the mountain. The average slope on this side of the volcano is 35 degrees, and Killy was caught on radar skiing more than 100 miles per hour. As he fell on the first run, he did the descent twice.
The mountain was first climbed by J. C. Bidwill in March 1839, the ascent being from the north-west. He reported that “The crater was the most terrific abyss I ever looked into or imagined … it was not possible to see above 10 yards into it from the quantity of steam which it was continually discharging”.
- "Tongariro". Global Volcanism Program. Smithsonian Institution. Retrieved 2018-04-06.
- "BIDWILL, John Carne". An Encyclopaedia of New Zealand. Ministry for Culture and Heritage / Te Manatū Taonga. 1966. Retrieved 2014-02-19.
- J. Mackintosh Bell (July 1912). "Some New Zealand Volcanoes". The Geographical Journal (Vol. 40, No. 1): 8–10. JSTOR 1778890.
- "GNS Alert Bulletin". GeoNet. Archived from the original on 2012-12-11. Retrieved 2013-12-24.
- "Volcanic Alert Bulletin NGA-2015/01 - Ngauruhoe Volcano". GeoNet.
- "Volcanic Alert Bulletin NGA-2015/03 - Ngauruhoe Volcano". GeoNet.
- Waikato Times.1 April 2013.
- Sibley, Brian. The Making of the Movie Trilogy The Lord of the Rings, Houghton Mifflin (2002).
- Ward, Alex (21 November 2012). "90 schoolchildren among tourists who flee for their lives as Lord of the Rings 'Mount Doom' volcano erupts". Daily Mail.
- GNS Science (25 March 2015). "Ngauruhoe".