Raoul Island
Template:Short description Template:Use New Zealand English Template:Use dmy dates Template:Infobox mountain
Raoul Island (Sunday Island; Template:Langx<ref>Template:Cite web</ref>) is the largest and northernmost of the main Kermadec Islands, Template:Cvt south south-west of 'Ata Island of Tonga and Template:Cvt north north-east of New Zealand's North Island. It has been the source of vigorous volcanic activity during the past several thousand years that was dominated by dacitic explosive eruptions, with the largest being VEI-6.
The area of the anvil-shaped island, including fringing islets and rocks mainly in the northeast, but also a few smaller ones in the southeast, is Template:Convert. The highest elevation is Moumoukai Peak, at an elevation of Template:Convert.
Although Raoul is the only island in the Kermadec group large enough to support settlement, it lacks a safe harbour, and landings from small boats can be made only in calm weather. The island consists of two mountainous areas, one with summits of Template:Convert and Template:Convert, and the other with a summit of Template:Convert, the two separated by a depression which is the caldera of the Raoul volcano.
History
Evidence from archaeological sites on the northern coast of Raoul Island indicate that Polynesians settled there in the 14th century.<ref>Template:Cite book</ref> A 1980 publication also suggested a lower layer of deposits dated to the 10th century, but this was rejected by the paper's author in 1991 in favour of the later date. Finds at the sites included stone implements of the Polynesian type, obsidian flakes, shells and charcoal. Obsidian of the same type has been found at early Māori sites at Shag River / Waihemo and Tai Rua, Otago on the South Island of New Zealand. There are also similarities to the Raoul settlement at archaic sites at Houhora and Papatowai. Higham and Johnson (1997) concluded that Raoul was settled from New Zealand but that the Kermadecs were a stepping stone in an early and rapid Polynesian migration from Polynesia to New Zealand and back although the occupation of the islands was relatively brief.<ref>Higham, Thomas and Johnson, Leigh (Oct 1997) The Prehistoric Chronology of Raoul Island, the Kermadec Group. Archaeology in Oceania, 32 No. 3 pp. 207–213. Wiley/JSTOR.</ref>
The island was uninhabited when first sighted by Western sailors and was named after Joseph Raoul, quartermaster of the Recherche, when it was sighted on 16 March 1793. Captain William Raven of the whaleship Britannia sighted the island on 6 March 1796 and called it Sunday Island, a name which was subsequently in common usage. Captain Henry Mangles Denham of HMS Herald charted the island in 1854.<ref>Template:Cite book</ref><ref>Template:Cite web</ref>
The last regular occupants, Tom Bell and his wife Frederica, spent thirty-six years on the island before the New Zealand government evacuated them in 1914.<ref name=Guilliatt>Template:Cite book</ref> A landing party sent to investigate the island found out how hasty the evacuation of the Bells was – a 1914 calendar was still pinned to the kitchen wall and the family's furniture, cutlery, and child's toys had remained in place.<ref name="Guilliatt" /> The family arrived with six children and five more were born there.<ref>Template:Cite book</ref>
From 27 May to 16 June 1917, the German raider Wolf, under the command of Korvettenkapitän Karl August Nerger, anchored in the protected bay to undertake engine overhaul and maintenance.<ref name="Guilliatt" /> During this period Wolf captured the New Zealand steamship Wairuna (3,950 tons) and the American sailing bark Winslow (570 tons), commandeering all cargo and coal from both ships.<ref name="Guilliatt" />
Weather station
The New Zealand government has permanently staffed Raoul Island since 1937 until the evacuation of staff at the beginning of 2020 due to uncertainties around the COVID-19 pandemic. It included a government meteorological and radio station and hostel for Department of Conservation (DOC) officers and volunteers.<ref name="nzg">Template:Cite web</ref> The station stands on the northern terraces of the island, about Template:Convert in elevation above the cliffs of Fleetwood Bluff.
The meteorological station (WMO ID 93997) was initially operated by New Zealand Post Office staff operating the radio station, but shortly after the end of World War 2, the New Zealand Meteorological Service took over the running of the station, with nine full-time staff. Each team undertook 12-month expeditions to the island to provide three hourly weather reportsTemplate:Citation needed and once daily radiosonde flights using hydrogen filled balloons at 10:30Template:Nbspam.<ref>Template:Cite web</ref> Weather reports were radioed back to New Zealand using HF radio to ZLW Wellington Radio.
In addition to its primary purpose as a meteorological station, staff at the station also maintained a seismic monitoring station, made once a week measurements of sea temperature at Fishing Rock and the lake levels and temperatures of Blue and Green Lakes.
In 1990 the surface weather observation programme was automated and the Department of Conservation took over responsibility for operational activities on the island.
Raoul Island Station remains the northernmost outpost of New Zealand.
2006 eruption – Mark Kearney
On 17 March 2006 at 8:21Template:Nbspa.m. NZDT, a 40-second long volcanic eruption occurred at the Green Lake. At the time, Mark Kearney, a DOC worker, was at the crater taking water temperature measurements. A Template:Convert area around Green Lake was affected with ash, mud and boulders. Two DOC workers were forced to turn back after going to the crater to search for Kearney.
Following the eruption, DOC decided to evacuate the remaining five staff members. A Mil Mi-8 helicopter and Piper PA-31 Navajo aircraft took off from Taupō at 11Template:Nbspa.m. that morning.<ref>Template:Cite news</ref> They arrived at the island in the late afternoon and undertook a 45-minute search for Kearney, but no sign was seen. The evacuated staff members were brought back to Auckland that evening.
A Royal New Zealand Air Force P-3 Orion made an overflight on 21 March to provide further information on how safe it was to approach Green Lake. The volcanologists aboard decided the area was still unsafe, and that the crater lake had risen by about Template:Convert compared to measurements taken on 17 March. There was no cloud or ash plume.<ref>Template:Cite news</ref>
A group of police, the five evacuated workers, three other DOC staff and scientific staff left Tauranga on 18 March for the three-day boat trip to Raoul aboard the RV Braveheart to recover Kearney's body.<ref>Template:Cite news</ref> They were able to undertake a limited search, but decided that it was extremely unlikely that Kearney survived given the amount of devastation in the area around Green Lake. The Braveheart began the journey back to the mainland on 25 March, with three of the DOC workers staying on the island to continue research.<ref name="searchers2006">Template:Cite news</ref> The three were joined by the other four evacuated workers at the start of May 2006. Two of the three will return to the mainland after the handover.<ref>Template:Cite news</ref>
Five hours after the eruption, the Aura satellite passed over and found an estimated Template:Convert of sulfur dioxide had been released.<ref>Alert Bulletin, Raoul Island volcano Template:Webarchive, 24 March 2006</ref> This confirmed that there were magmatic gases in the eruption, and the presence of degassing magma within the volcano. By the end of April, the activity in the area had decreased significantly and the "Alert Level" was lowered to 1.<ref>Alert Bulletin, Raoul Island volcano Template:Webarchive, 26 April 2006</ref>
HMNZS Te Mana left for Raoul on 24 August 2006 on a resupply mission. Also on board were Kearney's sister, Merryn McDermott; three representatives of the Ngāti Kurī iwi; and Chris Carter, the Minister of Conservation. During a service held on 28 August, the Ngāti Kurī representatives performed a tapu lifting ceremony.<ref>Template:Cite news</ref> A plaque was erected to honour Kearney. Te Mana also allowed some volcanic monitoring to be undertaken using its SH-2G Super Seasprite helicopter. During a dawn flight, sample bottles were filled with crater lake water.<ref>Template:Cite news</ref>
A report by the New Zealand Department of Labour into the death was released on 14 October 2006. It cleared the Department of Conservation and the Institute of Geological and Nuclear Sciences Ltd of any negligence related to the death of Kearney. The report stated that the eruption was unpredictable and there was no indication of imminent seismic activity.<ref>Template:Cite news</ref>
Located on an active margin between two tectonic plates, the Kermadec Islands also experience frequent earthquakes, the most recently significant of which occurred at 19:28:31 UTC on 4 March 2021.<ref>Template:Cite web</ref> The epicentre occurred south of Raoul and measured 8.1 on the moment magnitude scale, and as such is classified as a 'major' earthquake by the United States Geological Survey. Also of note on 31 January 2007 at 4:15:55 NZST a Magnitude 6.5 (Strong) earthquake shook the island. The epicentre was approximately Template:Convert S of Raoul and Template:Convert below the seabed. On 9 December 2007 at 8:28Template:Nbsppm NZST a magnitude 7.6 earthquake shook the area, centred approximately Template:Convert north of Raoul Island at a depth of Template:Convert.<ref>Template:Cite web</ref> On 30 September 2008 at 3:19:31 NZST a magnitude 7.0 earthquake centred Template:Convert S of Raoul occurred, with an approximate depth of Template:Convert.<ref>Template:Cite web</ref> More recently on 22 October 2011 at 05:57:17 NZST a Magnitude 7.4 earthquake originating at 28.941S 176.045W at a depth of 39 km occurred according to the United States Geological Survey.
July 2011 earthquake
7 July 2011 – 7:03Template:Nbspam. A 7.6 Magnitude earthquake occurred at a depth of 24 km, 211 km east of Raoul Island. 7 July 2011 – 8:51Template:Nbspam Pacific Tsunami Warning Centre scientist Barry Hirshorn told Newstalk ZB the quake generated a 1.9 metre tsunami at Raoul Island.<ref>Template:Cite news</ref>
October 2011 earthquake
22 October 2011 – 5:57Template:Nbsppm. A 7.4 magnitude earthquake occurred at a depth of Template:Convert, Template:Convert east of Raoul Island.
The Ministry of Civil Defence had issued the advisory while it assessed the severity of the threat to New Zealand. The Ministry was warning people in coastal areas to stay off beaches and out of the water. People were advised to avoid sightseeing and remain on alert in case the earthquake had generated a tsunami, however by mid-morning warnings had lifted.<ref>Template:Cite web</ref>
2012 – Mihai Muncus-Nagy
Template:Anchor Department of Conservation volunteer Mihai Muncus-Nagy, a 33-year-old biologist from Romania, went missing on Raoul Island on 2 January 2012.<ref name="Muncus-Nagy'">Template:Cite news</ref> He had gone to Raoul at the end of October 2011.<ref name="search off"/> His vehicle and gear were found close to where he had been carrying out water temperature readings on the morning of 2 January 2012.
The remaining staff and volunteers searched the shore, but found no further sign of him. A helicopter was sent to Raoul by the Rescue Coordination Centre New Zealand (RCCNZ) from Taupō to carry out an aerial search. A DOC boat was also used in the search.<ref name="search off"/>
Muncus-Nagy was presumed drowned.<ref name="search off">Template:Cite news</ref> Auckland District Court later found the Department of Conservation culpable in his death for failing to ensure his safety.<ref>Template:Cite news</ref>
March 2021 earthquake
4 March 2021 – 08:28 local time. An 8.1 magnitude earthquake occurred at a depth of Template:Convert, Template:Convert east of Raoul Island.<ref>Template:Cite web</ref> Owing to the COVID-19 pandemic, the island was uninhabited at the time.<ref>Template:Cite web</ref> The earthquake led to a tsunami warning for much of New Zealand, and evacuation of some coastal regions of the North Island.<ref>Template:Cite news</ref>
Geography
Template:Wikinews The island is about Template:Cvt northeast of Auckland and its location means it is a convenient earthquake and tsunami monitoring station for several Pacific nations.<ref name=GeonetRI>Template:Cite web</ref> Two Holocene calderas are found at Raoul. The older caldera, which cuts the centre of Raoul Island, is about Template:Cvt long and wide respectively. Denham caldera, formed during a major dacitic explosive eruption about 2200 years ago, truncated the western side of the island and is Template:Cvt long and wide respectively.
The Denham caldera was named for the nearby Denham Bay, itself named by Royal Navy Captain Henry Mangles Denham in HMS Herald, who came to complete a (chart) survey of the island on 2 July 1854. His son Fleetwood James Denham (16yrs) died from a tropical fever, and was buried near the beach at the head of Denham Bay, where a number of the grass-grown graves of former settlers were. The brass plaque heading this grave has been preserved.
Three small lakes, Blue Lake (Template:Convert,Template:Citation needed about 40% overgrown), Green Lake (Template:Convert) and Tui Lake (Template:Convert, drinking water quality) are located in the northern caldera of Raoul Island. The floor of the caldera surrounding the lakes is called Pumice Flats.
Climate
Raoul Island has a humid subtropical climate (Cfa) close to the border of tropical climate (Af). On 12 February 2022, the minimum temperature in the Raoul Island was 25.6 °C, this is the highest minimum temperature ever recorded in New Zealand.<ref>Template:Cite web</ref>
Geology
Raoul Island is a stratovolcano on the Tonga–Kermadec Ridge which is a back-arc volcanic chain associated with the 4 to 5 million year old Kermadec–Tonga subduction zone.<ref name="gvp">Template:Cite gvp</ref> Its formative lavas have erupted over at least the last 1.5 million years and range from basaltic to rhyolitic in composition.<ref name="Haase2014">Template:Cite journal</ref>Template:Rp There was a change from predominantly basaltic and andesitic volcanism to the more silicic dacite and rhyolitic volcanism about 3700 years ago.<ref name="Herbert2013">Template:Cite thesis</ref>Template:Rp
The Raoul volcano massif is over twice the area of the island extending off the seafloor Template:Cvt and has a total volume of Template:Cvt.<ref>Template:Cite journalTemplate:Rp</ref> Denham caldera's long axis is parallel to the tectonic fabric of the Havre Trough that lies west of the volcanic arc. There is a large undersea caldera about Template:Cvt to the northeast of the island in the volcanic edifice.<ref name="Herbert2013"/>Template:Rp<ref name="Rotella2015">Template:Cite journalTemplate:Rp</ref>
About Template:Cvt south of Raoul Island is a separate submarine volcanic edifice referred to as Raoul SW, and further on the volcanic Macauley Island.<ref name="Herbert2013"/>Template:Rp<ref name="Rotella2015"/>
Historical eruptions at Raoul during the 19th and 20th centuries have sometimes occurred simultaneously from both of the island's calderas, and have consisted of small-to-moderate phreatic eruptions, some of which formed ephemeral islands in Denham caldera. A Template:Convert high unnamed submarine cone, one of several located along a fissure on the lower NNE flank of Raoul volcano, has also erupted during historical time, and satellite vents at Raoul are concentrated along two parallel NNE-trending lineaments.
| Start Date<ref name="gvp"/> | End Date<ref name="gvp"/> | VEI<ref name="gvp"/> | Scale | Type<ref name="Herbert2013"/>Template:Rp | Comment<ref name="gvp"/> |
|---|---|---|---|---|---|
| Template:Dts | Template:Dts | 1 | Minor | - | One death.<ref name="searchers2006"/> The eruption lasted 30 minutes and Template:Cvt of sulfur dioxide gas emitted.<ref name=GeonetRI/> |
| Template:Dts | Template:Dts | 2 | Minor | Phreatic | From west side Green Lake and Denham caldera |
| Template:Dts | Template:Unknown | 0 | Minor | - | In sea about Template:Cvt NEE from Raoul Island, floating pumice observed.<ref name=GeonetRI/> |
| Template:Dts ± 4 days | Template:Dts | 3 | Minor | Phreatomagmatic | from Denham caldera and Green Lake. Two islands formed in Denham Bay which by 1877 were eroded to sealevel.<ref name=GeonetRI/> |
| Template:Dts | Template:Unknown | 3 | Minor | Phreatomagmatic | From Denham caldera and Smith Crater. A Template:Cvt circumference island, formed in Denham Bay, which had disappeared by 1854.<ref name=GeonetRI/> |
| approx. Template:Dts | Template:Unknown | - | - | Phreatic | Smith Breccia |
| Template:Dts ± 50 CE | Template:Unknown | 4 | Major | Phreatic | From Tui Lake |
| Template:Dts | Template:Unknown | - | - | Dacite | Sentinel tephra from possibly Denham caldera may be same eruptive sequence to Tui<ref name="Herbert2013"/>Template:Rp |
| Template:Dts ± 50 CE | Template:Unknown | 4 | Major | Dacite | Rangitahua Crater |
| Template:Dts CE | Template:Unknown | - | - | Basaltic andesite | Meyer Islands identified by tephrochronology |
| Template:Dts CE | Template:Unknown | 4 | Major | Phreatic | Expedition breccia<ref name="Herbert2013"/>Template:Rp |
| Template:Dts CE | Template:Unknown | 3 | Minor | Phreatic | Pukekohu Crater |
| Template:Dts CE | Template:Unknown | 4 | Major | Dacite | Green Lake |
| about 500 CE | Template:Unknown | - | - | Dacite | Pumice layer floated from crater lake dome<ref name="Herbert2013"/>Template:Rp |
| Template:Dts CE | Template:Unknown | 4 | Major | Dacite | Raynor tephra from south Raoul caldera |
| Template:Dts CE | Template:Unknown | 4 | Major | Basaltic andesite | Judith tephra from north flank of Moumoukai |
| Template:Dts BCE | Template:Unknown | 3 | Minor | Dacite | Bell tephra |
| Template:Dts ± 75 BCE | Template:Unknown | 6 | Major | Dacite | Fleetwood tephra from Denham caldera. At one studied spot on the island Template:Cvt of pumice is overlain by Template:Cvt of ignimbrite pyroclastic flow.<ref name="Worthington1999"/>Template:Rp |
| Template:Dts ± 150 BCE | Template:Unknown | 4 | Major | Dacite | Oneraki tephra,from southwest part of Raoul caldera |
| Template:Dts ± 100 BCE | Template:Unknown | 4 | Major | Dacite | Matatirohia tephra, from south east part of Raoul caldera |
| Template:Dts BCE | Template:Dts BCE | - | - | Basaltic andesite | Moumoukai formation assigned to Raoul<ref name="Herbert2013"/>Template:Rp |
| Template:Dts BCE | Template:Dts BCE | - | - | Basaltic andesite | Hutchison formation assigned to Denham caldera location<ref name="Herbert2013"/>Template:Rp |
| Template:Dts BCE | Template:Dts BCE | - | - | Basalt and basaltic andesite | D'Arcy formation assigned to Denham caldera location<ref name="Herbert2013"/>Template:Rp |
| Template:Dts BCE | Template:Dts BCE | - | - | Basalt and basaltic andesite | Boat Cove formation<ref name="Herbert2013"/>Template:Rp |
Volcanic risk
Immediate volcanic risk at Raoul is confined to any who are on the island at the time, or shipping in the vicinity.<ref>Template:Cite bookTemplate:Rp</ref> However larger eruptions could pose a serious danger to aircraft on commercial routes and generate tsunami. The eruption of about 250 BCE was about the same size as the 1883 eruption of Krakatoa.<ref name="Worthington1999">Template:Cite journal</ref>Template:Rp
Flora and fauna
Template:See also The scientific categorisation of the flora and fauna of the island began in 1854 when Template:HMS, captained by Henry Mangles Denham, arrived to complete the charting of the island. He arrived on the 2nd and was occupied till 24 July, during which time he frequently had to move the ship on account of the rough weather experienced. William Grant Milne and John MacGillivray, naturalists on board the Herald, made a small collection of plants on Raoul. This was forwarded by Captain Denham to Sir W. Hooker, and was described by Sir Joseph Hooker in the Journal of the Linnean Society for 1857.
A scientific expedition was undertaken by a group of naturalists to the Kermadec Islands in 1908.<ref name="Otago Witness 1908">Template:Cite news</ref> The expedition established its base at Denham Bay. During that expedition one of the naturalists, W. L. Wallace, discovered numerous new insect species including the beetle Saprosites raoulensis.<ref name="Broun 1910">Template:Cite journal</ref>
Raoul is part of the Kermadec Islands subtropical moist forests ecoregion and is largely covered with closed-canopy forest, predominantly of the evergreen Kermadec pōhutukawa (Metrosideros kermadecensis) and the Kermadec nikau palm (Rhopalostylis baueri, formerly described as Rhopalostylis cheesemanii). It is just far enough south that the occasional fertile coconut from Polynesia that washes up on shore and takes root will not survive in the longterm due to a lack of warmth.<ref>International Palm Society</ref> The island has no native land mammals and was formerly home to vast colonies of seabirds who nested in the forests. The islands may once have had a species of megapode (based on early settler records) and a subspecies of kererū.<ref>Tennyson, A. & Martinson, P. (2006) Extinct Birds of New Zealand Te Papa Press, Wellington Template:ISBN</ref> Currently, landbirds on the island include the Kermadec red-crowned parakeet (Cyanoramphus novaezelandiae cyanurus), the Australasian harrier, pūkeko, tūī and several introduced species.<ref>C. R. Veitch, C. M. Miskelly, G. A. Harper, G. A. Taylor, and A. J. D. Tennyson (2004) "Birds of the Kermadec Islands, South-west Pacific" Notornis 51(2): 61–90</ref> The island forms part of the Kermadec Islands Important Bird Area, identified as such by BirdLife International because it is an important site for nesting seabirds.<ref>BirdLife International. (2012). Important Bird Areas factsheet: Kermadec Islands. Downloaded from Template:Cite web on 3 February 2012.</ref>
Polynesian visitors introduced the Polynesian rat in the 14th century and Norway rats, cats and goats were introduced by European and American visitors in the 19th and 20th centuries. The rats and cats greatly reduced the seabird colonies, which mostly withdrew to offshore islets, and exterminated the red-crowned parakeet, the last confirmed record of resident parakeets for over a century being made in 1836. Although the goats did not eliminate the tree canopy as they did on other islands, they greatly reduced the understorey vegetation and were removed in 1986. The Department of Conservation eradicated rats and cats between 2002 and 2006, following which red-crowned parakeets soon returned naturally, presumably from the Herald Islets, Template:Convert away. The parakeets had been absent from the island for 150 years and their natural return was a notable event in parrot conservation.<ref>Template:Cite journal</ref><ref>Template:Cite news Template:Dead link</ref>
There are numerous invasive plant species on the island and a large scale weeding programme involving teams of DOC workers and volunteers has been under way for a number of years in an attempt to eradicate them. Myrtle Rust has been found on the island in 2017.<ref>Template:Cite web</ref>
The island is part of the Kermadec Islands Marine Reserve, New Zealand's largest marine reserve, which was created in 1990.
Satellite islands and rocks
The two largest satellite islands are North Island and South Island of Meyer Islands.
- Islands and rocks in the northeast of Raoul Island
- Fishing Rock
- Egeria Rock
- Meyer Islands
- North Island
- South Island
- Napier
- Nugent Island (northernmost island of New Zealand)
- Herald Islets
- Dayrell Island
- Chanter Islands
- Chanter (North) Island
- South Island
- West Island
- Islands and rocks in the southwest of Raoul Island
- Milne Islands
- Dougall Rocks
See also
- List of earthquakes in New Zealand
- List of extinct bird species since 1500
- List of islands of New Zealand
- List of volcanoes in New Zealand
- Lists of islands
- New Zealand outlying islands
- Uninhabited island
Notes
References
Further reading
- Oliver, R., 'The Vegetation of the Kermadec Islands'. Transactions and Proceedings of the Royal Society of New Zealand, Volume 42, 1909, p. 121. URL: RSNZ, accessed 3 January 2007.
- Polynesian stone implements
- Template:Cite gvp
External links
- Pages with broken file links
- Raoul Island
- Stratovolcanoes of New Zealand
- Active volcanoes
- Islands of the Kermadec Islands
- VEI-6 volcanoes
- Calderas of New Zealand
- Submarine calderas
- Island restoration
- Uninhabited islands of New Zealand
- Important Bird Areas of the Kermadec Islands
- Volcanic islands of New Zealand
- Volcanoes of the New Zealand outlying islands
- Holocene calderas