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70-518: Ngongotahā Valley is a valley formed by the Ngongotahā Stream west of Rotorua , in New Zealand. Springs on the stream were landscaped in 1939 and promoted as Paradise Valley Springs, and the main road into the valley is Paradise Valley Road. Mount Ngongotahā has a peak at 757 metres. A gondola / luge ride operates on the side of the mountain. The springs are still operating, and now include

140-605: A Treaty of Waitangi claim with the Ngāti Whakaue people to honour their broken contract, by agreeing to return the gifted lands that were no longer required for their original use. The town was connected to Auckland with the opening of the Rotorua Branch railway and commencement of the Rotorua Express train in 1894, resulting in the rapid growth of the town and tourism from this time forward. Guidebooks about

210-607: A spa town led to a 99-year lease of land from Ngāti Whakaue to the Government. The city first became a major site of tourism due to the Rotorua's close proximity to the Pink and White Terraces , until they were destroyed by the volcanic eruption of Mount Tarawera in 1886. Rotorua was elevated to borough status in 1922 and to city status 40 years later. Rotorua is a major destination for both domestic and international tourists;

280-592: A Māori- and English-medium special character school from years 1–10. It currently has around 100 students. Students here need to attend a mainstream secondary school or Kura Kaupapa Māori for their senior secondary schooling. Rotorua has four Kura Kaupapa Māori : Rotorua has several media organisations, including the Rotorua Daily Post , More FM Rotorua and The Hits Rotorua . Rotorua's sister cities are: Geothermal gradient Strictly speaking, geo -thermal necessarily refers to Earth, but

350-711: A Ngāpuhi-led coalition invaded Rotorua. The force, which also included Ngāti Whātua and some Waikato Tainui , landed at Tauranga and headed up the Pongakawa valley to attack Mokoia Island Te Arawa fell back after the loss of 170 men and were defeated by Ngāpuhi, and utu was satisfied. The first European in the area was probably Phillip Tapsell who was trading from the Bay of Plenty coast at Maketu from 1828. He later married into Te Arawa and became highly regarded by them. Missionaries Henry Williams and Thomas Chapman visited in 1831 and Chapman and his wife established

420-475: A generator. The efficiency of converting the geothermal heat into electricity depends on the temperature difference between the heated fluid (water or steam) and the environmental temperature, so it is advantageous to use deep, high-temperature heat sources. On a worldwide scale, the heat stored in Earth's interior provides an energy that is still seen as an exotic source. About 10 GW of geothermal electric capacity

490-413: A higher temperature than rocks at a somewhat deeper level. Negative geothermal gradients are also found at large scales in subduction zones. A subduction zone is a tectonic plate boundary where oceanic crust sinks into the mantle due to the high density of the oceanic plate relative to the underlying mantle. Since the sinking plate enters the mantle at a rate of a few centimeters per year, heat conduction

560-516: A joint project by the Bay of Plenty Regional Council and Rotorua Lakes Council to reduce the risk of future floods is ongoing. Ngongotahā Valley statistical area, which also includes Mamaku , covers 177.50 km (68.53 sq mi) and had an estimated population of 1,720 as of June 2024, with a population density of 9.7 people per km. Ngongotahā Valley had a population of 1,590 at the 2018 New Zealand census , an increase of 180 people (12.8%) since

630-664: A mission at Te Koutu in 1835. This was abandoned within a year, but Chapman returned in 1838 and established a second mission at Mokoia Island. The lakeshore was a prominent site of skirmishes during the New Zealand Wars of the 1860s. William Fox advocated for turning the Rotorua region into a national park , inspired by the Yellowstone in the United States . Conversely, the Te Arawa community suggested

700-453: A route to Tauranga via Pyes Pa, while State Highway 5 turns westward, connecting to State Highway 1 at Tīrau and providing the main route into Rotorua from Hamilton and Auckland . To the south, State Highway 5 provides the main route from Taupō , Hawke's Bay , Manawatu , and Wellington . State Highway 30 runs southwest to northeast through the city. It enters the city in the southwest (running concurrently with SH 5), before crossing

770-675: A significant contribution to geothermal heat production. The continental crust is abundant in lower density minerals but also contains significant concentrations of heavier lithophilic elements such as uranium. Because of this, it holds the most concentrated global reservoir of radioactive elements found in Earth. Naturally occurring radioactive elements are enriched in the granite and basaltic rocks, especially in layers closer to Earth's surface. These high levels of radioactive elements are largely excluded from Earth's mantle due to their inability to substitute in mantle minerals and consequent enrichment in melts during mantle melting processes. The mantle

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840-634: A spa town and major tourist resort since the 1800s, many of Rotorua's buildings reflect this history. Government Gardens , close to the lake-shore at the eastern edge of the town, include the Rotorua Museum of Art and History housed in the large Tudor-style bath house building, and the Art Deco style Blue Baths , noted for its embrace of mixed sex bathing in the 1930s. As of October 2023 , both buildings are closed because of earthquake strength concerns. There are many geothermal attractions in

910-544: A wildlife park. Another visitor attraction on the slopes of Mount Ngongotahā is the Wingspan National Bird of Prey Centre . It is a captive breeding facility and visitor centre located in the Ngongotahā Valley. Wingspan undertakes conservation, education and research activities related to birds of prey found in New Zealand, and provides demonstrations of falconry . The stream is prone to flooding but

980-522: Is Te Rotorua-nui-a-Kahumatamomoe . Roto means 'lake' and rua means 'two' or in this case, 'second' – Rotorua thus meaning 'Second lake'. Kahumatamomoe was the uncle of the Māori chief Ihenga , the ancestral explorer of the Te Arawa . It was the second major lake the chief discovered, and he dedicated it to his uncle. It is the largest of a multitude of lakes found to the northeast, all connected with

1050-408: Is 0.087 watt/square metre on average (0.03 percent of solar power absorbed by Earth ), but is much more concentrated in areas where the lithosphere is thin, such as along mid-ocean ridges (where new oceanic lithosphere is created) and near mantle plumes . Earth's crust effectively acts as a thick insulating blanket which must be pierced by fluid conduits (of magma, water or other) in order to release

1120-443: Is determined by the mantle adiabat, rather than by the conductive heat transfer processes that predominate in the lithosphere, which acts as a thermal boundary layer of the convecting mantle. Heat flows constantly from its sources within Earth to the surface. Total heat loss from Earth is estimated at 44.2 TW ( 4.42 × 10 Watts ). Mean heat flow is 65 mW/m over continental crust and 101 mW/m over oceanic crust . This

1190-574: Is home to the central campus of Toi Ohomai Institute of Technology , which provides a range of certificates, diplomas and a limited number of degree-level programmes. The largest programmes on offer are Te Reo Māori (Māori language), nursing , forestry , business, computing , tourism and hospitality . As of June 2022 , Toi Ohomai Institute of Technology is a business division of Te Pūkenga – New Zealand Institute of Skills and Technology. Rotorua has five secondary schools: Students can also attend Te Rangihakahaka Centre for Science and Techbnology,

1260-584: Is installed around the world as of 2007, generating 0.3% of global electricity demand. An additional 28 GW of direct geothermal heating capacity is installed for district heating, space heating, spas, industrial processes, desalination and agricultural applications. The geothermal gradient varies with location and is typically measured by determining the bottom open-hole temperature after borehole drilling. Temperature logs obtained immediately after drilling are however affected due to drilling fluid circulation. To obtain accurate bottom hole temperature estimates, it

1330-537: Is known for its Māori cultural tourism. Rotorua is served by state highways 5 , 30 , and 30A , and the Thermal Explorer Highway touring route, with state highways 33 and 36 terminating on the outskirts of the city. State Highway 5, running concurrently with the Thermal Explorer Highway, is the main north–south route through Rotorua, bypassing the city centre to the west. North of the city at Ngongotahā, State Highway 36 splits off to provide

1400-536: Is located 9 km (6 mi) northeast of the city centre, off State Highway 30. Air New Zealand provides daily turbo-prop flights between Rotorua and Auckland , Wellington , and Christchurch airports. Previously Qantas also operated Boeing 737 aircraft from Christchurch, but upon their departure from domestic flights in New Zealand this was discontinued. Scenic and chartered flights in both helicopters and float planes are operated by Volcanic Air, who are based on Rotorua's lake front. From 2009 to 2015 there

1470-423: Is mostly made up of high density minerals with higher concentrations of elements that have relatively small atomic radii, such as magnesium (Mg), titanium (Ti), and calcium (Ca). [W/kg nuclide] [years] [kg nuclide/kg mantle] [W/kg mantle] The geothermal gradient is steeper in the lithosphere than in the mantle because the mantle transports heat primarily by convection, leading to a geothermal gradient that

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1540-564: Is necessary for the well to reach stable temperature. This is not always achievable for practical reasons. In stable tectonic areas in the tropics , a temperature-depth plot will converge to the annual average surface temperature. However, in areas where deep permafrost developed during the Pleistocene , a low temperature anomaly can be observed that persists down to several hundred metres. The Suwałki cold anomaly in Poland has led to

1610-490: Is sited on the southern shores of Lake Rotorua , from which it takes its name. It is the seat of the Rotorua Lakes District , a territorial authority encompassing Rotorua and several other nearby towns. It has an estimated resident population of 58,800, making it the country's 13th largest urban area , and the Bay of Plenty's second-largest urban area behind Tauranga . Māori first settled in Rotorua in

1680-471: Is thought to have temperatures in the range of 4000 to 7000 K, and the pressure at the centre of the planet is thought to be about 360  GPa (3.6 million atm). (The exact value depends on the density profile in Earth.) Because much of the heat is provided for by radioactive decay, scientists believe that early in Earth's history, before nuclides with short half-lives had been depleted, Earth's heat production would have been much higher. Heat production

1750-607: The 2013 census , and an increase of 126 people (8.6%) since the 2006 census . There were 540 households, comprising 795 males and 795 females, giving a sex ratio of 1.0 males per female. The median age was 39.6 years (compared with 37.4 years nationally), with 363 people (22.8%) aged under 15 years, 267 (16.8%) aged 15 to 29, 753 (47.4%) aged 30 to 64, and 207 (13.0%) aged 65 or older. Ethnicities were 81.1% European/ Pākehā , 31.1% Māori , 2.3% Pacific peoples , 2.6% Asian , and 1.9% other ethnicities. People may identify with more than one ethnicity. The percentage of people born overseas

1820-727: The Fish and Game New Zealand hatchery at Ngongotahā . The lakes are also used for event venues; Rotorua hosted the 2007 World Waterski Championships and Lake Rotorua was the venue for the World Blind Sailing Championships in March 2009. Lake Rotorua is also used as a departure and landing point for float planes. The Rotorua urban area, as defined by Statistics New Zealand, covers 46.06 km (17.78 sq mi) and incorporates 26 statistical areas. It has an estimated population of 58,800 as of June 2024. Before

1890-758: The Mayor of Rotorua . She is the first woman of Māori descent to hold the role. Rotorua is covered by the Rotorua electorate for the general roll and the Waiariki electorate for the Māori roll. In 2022, the gross domestic product (GDP) of the Rotorua District was $ 4.241 billion, representing 1.2% of New Zealand's total GDP. The sector with the largest contribution to the Rotorua District GDP

1960-498: The polar ice caps flowing along ocean bottoms tends to maintain a constant geothermal gradient throughout Earth's surface. If the rate of temperature increase with depth observed in shallow boreholes were to persist at greater depths, temperatures deep within Earth would soon reach the point where rocks would melt. We know, however, that Earth's mantle is solid because of the transmission of S-waves . The temperature gradient dramatically decreases with depth for two reasons. First,

2030-429: The 'Land of Boiling Water' also proliferated. During the 1880s, tourists, especially from Australia, started visiting Rotorua to witness its natural marvels like the Pink and White Terraces until these were destroyed in a volcanic eruption in 1886 . Rotorua was established as a borough in 1922, elected its first mayor in 1923, and declared a city in 1962 before becoming a district in 1979. The city of Rotorua and

2100-593: The 14th century, and a thriving pā was established at Ohinemutu by the people who would become Ngāti Whakaue . The city became closely associated with conflict during the Musket Wars of the 1820s. Ohinemutu was invaded by a Ngāpuhi -led coalition in 1823, commanded by Hongi Hika and Pōmare I . In the 19th century early European settlers had an interest in developing Rotorua, due to its unique geothermal activity in Rotorua and its surrounding area. Then, efforts by Māori and Europeans alike to establish Rotorua as

2170-792: The 2023 census, the urban area had a larger boundary, covering 48.04 km (18.55 sq mi). Using that boundary, The Rotorua urban area had a usual resident population of 54,204 at the 2018 New Zealand census , an increase of 5,289 people (10.8%) since the 2013 census . There were 26,211 males and 27,993 females, giving a sex ratio of 0.936 males per female. Of the total population, 12,366 people (22.8%) were aged up to 15 years, 11,052 (20.4%) were 15 to 29, 22,980 (42.4%) were 30 to 64, and 7,809 (14.4%) were 65 or older. In terms of ethnicity, 59.2% were European/Pākehā, 42.3% were Māori, 6.2% were Pacific peoples, 11.5% were Asian, and 1.5% were other ethnicities (totals add to more than 100% since people could identify with multiple ethnicities). Rotorua has

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2240-561: The CBD, provides class 5 whitewater kayaking and rafting through a spectacular tree lined gorge. Another visitor attraction in the Ngongotahā area is the Wingspan National Bird of Prey Centre . It is a captive breeding facility and visitor centre located in the Ngongotahā Valley. Wingspan undertakes conservation, education and research activities related to birds of prey found in New Zealand, and provides demonstrations of falconry . Rotorua

2310-564: The Rotorua Caldera and nearby Mount Tarawera . The name can also mean the equally appropriate 'Crater lake'. A common nickname for Rotorua is "Sulphur City" due to the hydrogen sulphide emissions, which gives the city a smell similar to "rotten eggs", as well as "Rotten-rua" combining its legitimate name and the rotten smell prevalent. Another common nickname is "Roto-Vegas", likening the city's own strip of road flanked by businesses and restaurants to that of Las Vegas . The area

2380-672: The Rotorua area, including: The especially pungent smell in the central-east 'Te Ngae' area is due to the dense sulphur deposits located next to the southern boundary of the Government Gardens, in the area known as 'Sulphur Point'. Another of Rotorua's attractions is mountain biking . Rotorua was listed as one of the Top 6 mountain biking destinations globally by the International Mountain Biking Association in 2015, when they awarded Rotorua

2450-419: The adjacent Lake Rotorua are located within the Rotorua Caldera that was formed in a major volcanic eruption approximately 240,000 years ago. The caldera is the source of the geothermal activity that is a key feature of the city and surrounding region. The Rotorua region enjoys a mild temperate climate ( Cfb ). Rotorua is situated inland from the coast and is sheltered by high country to the south and east of

2520-424: The city, resulting in less wind than many other places in New Zealand. During the winter months, June – August, temperatures can drop below 0 °C. Frost is common in Rotorua during its winter months, with an average of 57 ground frosts annually, and 20 nights per year below 0 °C. Snowfall in Rotorua is rare, and since the 1970s has only been recorded twice. On 15 August 2011 and 13 July 2017, snowflakes fell in

2590-497: The concept may be applied to other planets. In SI units , the geothermal gradient is expressed as °C/km, K/km, or mK/m. These are all equivalent. Earth's internal heat comes from a combination of residual heat from planetary accretion , heat produced through radioactive decay , latent heat from core crystallization, and possibly heat from other sources. The major heat-producing nuclides in Earth are potassium-40 , uranium-238 , uranium-235 , and thorium-232 . The inner core

2660-423: The corresponding high temperatures. Generating electrical power from geothermal resources requires no fuel while providing true baseload energy at a reliability rate that constantly exceeds 90%. In order to extract geothermal energy, it is necessary to efficiently transfer heat from a geothermal reservoir to a power plant, where electrical energy is converted from heat by passing steam through a turbine connected to

2730-495: The depths of dozens to hundreds of meters contain information about the climate of the last hundreds to thousands of years. Depending on the location, these may be colder than current temperatures due to the colder weather close to the last ice age , or due to more recent climate change. Negative geothermal gradients may also occur due to deep aquifers , where heat transfer from deep water by convection and advection results in water at shallower levels heating adjacent rocks to

2800-514: The end of 2021. The city is also served by InterCity and services to local tourist sites. Edwin Robertson, who died aged 74 in 1931, started with pack horses in 1869 and ran coaches from 1873. In 1902, the Tauranga route was sold and became Robertson & Co, then, about 1903, Rotorua Motor Coaching Co. Ltd. In 1904, Hot Lakes Transport, which ran trips to Taupō, Waiotapu and all

2870-660: The establishment of a township centred around Rotorua's thermal springs, with the intent of developing a Polynesian Spa and health resort where tourists could indulge in hot pools. In 1880, instead of selling the land, the Ngāti Whakaue people leased 50 acres to the Crown under the Fenton Agreement, granting the government the authority to offer 99-year leases on their behalf. Revenues from leases helped fund Rotorua Boys' High School , and increased significantly upon

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2940-497: The expiry of the 99-year leases. The eponymous Fenton Street in the modern city’s CBD bears the judge’s name. Nevertheless, the enactment of the Thermal Springs District Act in 1881 gave the government exclusive rights to both purchase and lease lands containing hot springs, lakes, or river, and as a result, by the turn of the century, nearly half of the Rotorua blocks were sold. In 1993, the Crown settled

3010-742: The gold level ride centre status. The Whakarewarewa forest includes over 150 km of mountain bike trails and in August 2006 was a host of the UCI Mountain Bike and Trials World Championships . Each year, from 2015–present, Rotorua has hosted a round of the Crankworx World Tour . The Rotorua Pistol club is among the largest in the Southern Hemisphere and hosted the 2013 Australasian IPSC Handgun Championship. The Kaituna River , 15 minutes drive northeast of

3080-410: The gradient of the stabilized regime is projected above this point to its intersection with present-day annual average temperature, the height of this intersection above present-day surface level gives a measure of the extent of Holocene uplift and erosion. In areas of Holocene subsidence and deposition (Fig. 2) the initial gradient will be lower than the average until it reaches a point where it joins

3150-467: The heat underneath. More of the heat in Earth is lost through plate tectonics, by mantle upwelling associated with mid-ocean ridges. Another major mode of heat loss is by conduction through the lithosphere , the majority of which occurs in the oceans due to the crust there being much thinner and younger than under the continents. The heat of Earth is replenished by radioactive decay at a rate of 30 TW. The global geothermal flow rates are more than twice

3220-533: The highest proportion of Māori of any city in New Zealand. In October 2013, Steve Chadwick was elected Mayor of Rotorua and was re-elected in the 2016 mayoral election and the 2019 mayoral election . She previously served as the Member of Parliament for Rotorua between 1999 and 2008, and served as a Cabinet Minister in the Fifth Labour Government . In 2022, Tania Tapsell was elected as

3290-407: The human population continues to grow, so does energy use and the correlating environmental impacts that are consistent with global primary sources of energy. This has caused a growing interest in finding sources of energy that are renewable and have reduced greenhouse gas emissions. In areas of high geothermal energy density, current technology allows for the generation of electrical power because of

3360-548: The lakes, and Rotorua Motor Coaching added motor cars to their fleets of coaches. In 1905 E. Robertson & Co moved from Ohinemutu to the new town, close to the new railway station, which remained the main stop until InterCity moved to their stop from Hinemoa / Fenton Street to the Tourism Office in 1995. The last coach ran in 1919. When Hot Lakes Transport's assets were sold in 1920, they had 10 coaches and 3 motor cars. In September 1920, Rotorua Motor Transport Co.

3430-433: The margins of tectonic plates, increasing the geothermal gradient in the vicinity, but only the outer core is postulated to exist in a molten or fluid state, and the temperature at Earth's inner core/outer core boundary, around 3,500 kilometres (2,200 mi) deep, is estimated to be 5650 ± 600 Kelvin . The heat content of Earth is 10 joules . In Earth's continental crust, the decay of natural radioactive nuclides makes

3500-422: The mechanism of thermal transport changes from conduction , as within the rigid tectonic plates, to convection , in the portion of Earth's mantle that convects. Despite its solidity , most of Earth's mantle behaves over long time-scales as a fluid , and heat is transported by advection , or material transport. Second, radioactive heat production is concentrated within the crust of Earth, and particularly within

3570-430: The national economy. As a major visitor destination, Rotorua District has a much higher proportion of people in employed in accommodation (3.3%) than the national average (1.1%). Tourism contributed $ 231 million (5.5%) to the district GDP, compared with 2.8% nationally. The four largest industries in the district, based on employment, were hospitals, accommodation, cafes and restaurants, and primary education. Known as

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3640-575: The rate of human energy consumption from all primary sources. Global data on heat-flow density are collected and compiled by the International Heat Flow Commission (IHFC) of the IASPEI / IUGG . Heat from Earth's interior can be used as an energy source, known as geothermal energy . The geothermal gradient has been used for space heating and bathing since ancient Roman times, and more recently for generating electricity. As

3710-467: The recognition that similar thermal disturbances related to Pleistocene- Holocene climatic changes are recorded in boreholes throughout Poland, as well as in Alaska , northern Canada , and Siberia . In areas of Holocene uplift and erosion (Fig. 1) the shallow gradient will be high until it reaches a point (labeled "Inflection point" in the figure) where it reaches the stabilized heat-flow regime. If

3780-479: The service and the location of the station being a 15-minute walk from the town centre in an industrial area, passenger services stopped in October 2001. Freight services on the line declined over the decades until the nightly freight service stopped in 2000, largely due to a continual move of freight and passengers onto road transport using ever-improving highways in the region. The line is currently disused. Rotorua

3850-675: The southern suburbs to the shore of Lake Rotorua east of the city centre. It then runs through the suburb of Te Ngae, before splitting off SH 33 to continue eastwards. State Highway 30A runs northwest to southeast, connecting State Highways 5 and 30 with each other via the city centre. Rotorua has a local bus service, with 11 routes under the Baybus brand, serving the urban area, mostly at half-hourly intervals, operated by Reesby Buses . Bike racks were introduced in 2017 and Bee Cards for fares on 27 July 2020. Trial commuter services between Rotorua and Tauranga are running in each direction until

3920-500: The stabilized heat-flow regime. Variations in surface temperature, whether daily, seasonal, or induced by climate changes and the Milankovitch cycle , penetrate below Earth's surface and produce an oscillation in the geothermal gradient with periods varying from a day to tens of thousands of years, and an amplitude which decreases with depth. The longest-period variations have a scale depth of several kilometers. Melt water from

3990-631: The stage for further raids in the modern Rotorua area. Ngāpuhi and its allies launched an ambitious invasion of the Waikato in 1822, with a battalion led by junior chief Te Pae-o-te-Rangi were ambushed and slaughtered by Ngāti Whakaue for trespassing into Rotorua. This was apparently at the insistence of Te Rauparaha ; under Māori customary law the attack demanded utu . Ngāpuhi commander Hongi Hika convened with his fellow chiefs Pōmare I and Te Wera Hauraki to propose war, and thus in February 1823

4060-602: The temperature produced by the local weather, decaying to approximately the annual mean-average ground temperature (MAGT) at a shallow depth of about 10-20 metres depending on the type of ground, rock etc.; it is this depth which is used for many ground-source heat pumps . The top hundreds of meters reflect past climate change; descending further, warmth increases steadily as interior heat sources begin to dominate. Temperature within Earth increases with depth. Highly viscous or partially molten rock at temperatures between 650 and 1,200 °C (1,200 and 2,200 °F) are found at

4130-525: The tourism industry is by far the largest industry in the district. It is known for its geothermal activity and Māori cultural tourism, and features geysers – notably the Pōhutu Geyser at Whakarewarewa – and hot mud pools. This thermal activity is sourced to the Rotorua Caldera , in which the town lies. The name Rotorua comes from the Māori language , where the full name for the city and lake

4200-526: The town centre, and during the July 2017 snowfall, snow accumulated in the nearby Mamaku ranges and in the outer reaches of the district, where snowfall occurs on average once every three years. The Rotorua region has 17 lakes, known collectively as the Lakes of Rotorua. Fishing, waterskiing, swimming and other water activities are popular in summer. Several of the lakes are stocked for sports fishing with trout from

4270-441: The upper few hundreds of meters near the surface. Because of the low thermal diffusivity of rocks, deep underground temperatures are hardly affected by diurnal or even annual surface temperature variations. At depths of a few meters, underground temperatures are therefore similar to the annual average surface temperature. At greater depths, underground temperatures reflect a long-term average over past climate, so that temperatures at

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4340-501: The upper part of the crust, as concentrations of uranium , thorium , and potassium are highest there: these three elements are the main producers of radioactive heat within Earth. Thus, the geothermal gradient within the bulk of Earth's mantle is of the order of 0.5 kelvin per kilometer, and is determined by the adiabatic gradient associated with mantle material ( peridotite in the upper mantle). Negative geothermal gradients occur where temperature decreases with depth. This occurs in

4410-461: Was $ 28,100, compared with $ 31,800 nationally. 150 people (12.2%) earned over $ 70,000 compared to 17.2% nationally. The employment status of those at least 15 was that 618 (50.4%) people were employed full-time, 198 (16.1%) were part-time, and 57 (4.6%) were unemployed. Rotorua Rotorua ( Māori:  [ ˌ ɾ ɔ t ɔ ˈ ɾ ʉ a ] ) is a city in the Bay of Plenty Region of New Zealand 's North Island . It

4480-428: Was 10.9, compared with 27.1% nationally. Although some people chose not to answer the census's question about religious affiliation, 58.7% had no religion, 28.5% were Christian , 1.3% had Māori religious beliefs , 0.2% were Buddhist and 2.1% had other religions. Of those at least 15 years old, 138 (11.2%) people had a bachelor's or higher degree, and 291 (23.7%) people had no formal qualifications. The median income

4550-412: Was a site of heavy conflict during the Musket Wars . During the early 1820s, the large Northern iwi Ngāpuhi had begun expanding outwards further south, driving Ngāti Pāoa and their chief Te Hīnaki from modern-day South Auckland , and launched periodic raids into the Bay of Plenty . A military expedition into the Bay of Plenty by a combined Ngāpuhi and Ngāti Maru nō Hauraki force in 1818 had set

4620-432: Was also an international link, with direct Sydney to Rotorua flights. Rotorua is connected to the rail network by the Rotorua Branch line from Putāruru . Until 2001, passenger trains ran from Auckland to Rotorua via Hamilton daily using Silver Fern railcars, terminating north of the town centre at Koutu (the original station on Amohau Street was closed and relocated to Koutu in 1989). However, owing to poor advertising of

4690-435: Was formed and took over Hot Lakes Transport Co. and Rotorua Motor Coaching Co, continuing with similar services. In 1926, a consortium of local operators formed Rotorua Bus Co. During 1922, Kusab's transport company became K Motors, which was taken over by the railways in 1938. Rotorua Motor Transport and Rotorua Bus Co followed in 1940 and all became part of New Zealand Railways Road Services . Rotorua Regional Airport

4760-455: Was high value services (professional, managerial, as well as scientific and technical occupations), at 20%. This is less than the 26.7% contribution that high value services make to the national economy. The next highest contribution to the district GDP was from goods-producing industries representing 17.8% in the district GDP, versus 18.5% in the national economy. Primary industries, agriculture and forestry, contributed 10.2%, compared with 5.8% in

4830-542: Was initially settled by Māori of the Te Arawa iwi in the 14th century, and a thriving pā was built at Ohinemutu by the shores of Lake Rotorua . According to Te Arawa folklore, the city's bountiful geothermal springs had resulted from a plea by Ngātoro-i-rangi , an ancestral tohunga , for the gods to send fire-bearing spirits from Hawaiki , the semi-mythological Māori homeland. The Te Arawa Māori who lived at Ohinemutu eventually began to call themselves Ngāti Whakaue , after their ancestor Whakaue Kaipapa . Rotorua

4900-412: Was twice that of present-day at approximately 3 billion years ago, resulting in larger temperature gradients within Earth, larger rates of mantle convection and plate tectonics , allowing the production of igneous rocks such as komatiites that are no longer formed. The top of the geothermal gradient is influenced by atmospheric temperature . The uppermost layers of the solid planet are at

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