The Trewartha climate classification ( TCC ), or the Köppen–Trewartha climate classification ( KTC ), is a climate classification system first published by American geographer Glenn Thomas Trewartha in 1966. It is a modified version of the Köppen–Geiger system , created to answer some of its deficiencies. The Trewartha system attempts to redefine the middle latitudes to be closer to vegetation zoning and genetic climate systems.
18-663: Petre Bay is a large bay which comprises about half of the west coast of Chatham Island , the largest island in New Zealand 's Chatham Islands archipelago . It is some 20 kilometres (12 mi) in extent, and contains the far smaller Waitangi Bay, where the island group's largest settlement, Waitangi is located. The bay is named after Lord Petre , a director of the New Zealand Company . 43°52′S 176°33′W / 43.867°S 176.550°W / -43.867; -176.550 This article about
36-483: A mean temperature of 10 °C (50 °F) or higher: The tropical climates and polar climates remained the same as in the original Köppen climate classification. The "highland" climate is ambiguously defined. Newer users of KTC generally omit this option. This is the tropical climate realm, defined the same as in Köppen's scheme (i.e., all 12 months average 18 °C (64.4 °F) or above). The A climates are
54-463: A monthly mean air temperature below 10 °C (50 °F). Polar climates have two subtypes, Ft ( tundra ) and Fi ( ice cap ): Highland climates are those in which altitude plays a role in determining climate classification. Specifically, this would apply if correcting the average temperature of each month to a sea-level value—using the formula of adding 5.6 °C (10.1 °F) for each 1,000 meters (3,281 ft) of elevation—would cause
72-417: A population of under 200 in 2017. Chatham Island (or "Isle") is featured in the first and in the final chapter of Cloud Atlas , the 2004 novel by David Mitchell . The novel was adapted for screen in 2012. Trewartha climate classification Trewartha's modifications to the 1884 Köppen climate system sought to reclass the middle latitudes into three groups, according to how many months have
90-419: Is over 150 m above sea level. The south coast of the island is mostly cliffs 100 m high or more. The highest point of the island (299 m) lies close to its southernmost point. Chatham Island has an oceanic climate ( Koppen : Cfb ) characterised by a narrow temperature range and relatively frequent rainfall. Their isolated position far from any sizeable landmass renders the record high temperature for
108-708: Is said to be "halfway between the equator and the pole, and right on the International Date Line ", although that point is 173 miles WSW of the island's westernmost point. The island is called Rekohu ("misty skies") in Moriori , and Wharekauri in Māori . The island was named after the survey ship HMS Chatham which was the first European ship to locate the island in 1791. It covers an area of 920 km (355 sq mi). Chatham Island lies 650 km (404 mi) south-east of Cape Turnagain ,
126-504: The C climate group encompasses subtropical climates, which have 8 or more months with a mean temperature of 10 °C (50 °F) or higher. There are only two types within the C or subtropical climate group: In the Trewartha scheme the D climate group encompasses temperate climates that have 4 to 7 months with a mean temperature of 10 °C (50 °F) or higher. D climate groups have two types: Most of Europe north of
144-491: The Trewartha climate classification , Chatham Island has a humid subtropical climate (Cf) for the lack of cold weather during the winter and a daily mean temperature above 10 °C (50 °F) for eight months or more. Chatham Island hosts the only known breeding population of the endemic and critically endangered magenta petrel or tāiko ( Pterodroma magentae ). The seabird was thought to be extinct until 1978, and had
162-413: The 44th parallel exhibits a Do or Dc climate type. This represents subarctic and subpolar oceanic climate realms, defined the same as in Köppen's scheme, where 1 to 3 months have an average temperature of 10 °C (50 °F) or above. In this climate zone there is only a short period (normally 50 to 90 days) that is frost free. In the original scheme, this group was not further divided; later,
180-420: The climate to fit into a different thermal group from that into which the actual monthly temperatures place it. Sometimes G is used instead of H if the above is true and the altitude is between 500 and 2,500 meters (1,640 and 8,202 ft), but the G or H is placed in front of the applicable thermal letter rather than replacing it. The second letter used reflects the corrected monthly temperatures, not
198-539: The designations Eo and Ec were created: As in Group D , a third letter can be added to indicate seasonality of precipitation. There are no separate counterparts to the Köppen Dfd , Dwd , and Dsd climate types in Trewartha's scheme, but a letter can optionally be added to the end of the symbol to indicate the temperature of the coldest month ( see below ). This is the polar climate group, where all months have
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#1732802409350216-476: The geography of New Zealand 's outlying islands is a stub . You can help Misplaced Pages by expanding it . Chatham Island Chatham Island ( / ˈ tʃ æ t ə m / CHAT -əm ) ( Moriori : Rēkohu , lit. 'Misty Sun'; Māori : Wharekauri ) is the largest island of the Chatham Islands group, in the south Pacific Ocean off the eastern coast of New Zealand 's South Island . It
234-428: The hills at the south end of the island. The next largest lakes are Rangitahi and Huro , respectively northeast and southwest of Te Whanga. The central and north part of Chatham Island are mostly flat, with altitudes ranging from a few metres on the northeast and centre to 50 m on the northwest, but with a few scattered hillocks. The south part is higher, generally sloping down towards north and west; about half of it
252-538: The main settlement (Waitangi) just 23.8 °C (74.8 °F). The climate is cool, wet and windy, with average high temperatures between 15 and 20 °C (59 and 68 °F) in summer, and between 5 and 10 °C (41 and 50 °F) in July (in the Southern Hemisphere winter). Snowfall is extremely rare, the fall recorded near sea level in July 2015 marking the first such reading for several decades. Under
270-609: The mean annual temperature in degrees Celsius, and P denoting the percentage of total precipitation received in the six high-sun months (April through September in the Northern Hemisphere , October through March in the Southern ). Unlike in Köppen's scheme, no thermal subsets exist within this group in Trewartha's, unless the Universal Thermal Scale (see below) is used. In the Trewartha scheme
288-468: The nearest point of mainland New Zealand to the island. The geography of the roughly T-shaped island is dominated by three features: two bays and a lagoon. More than half of the west coast of Chatham is taken up by the deep indentation of Petre Bay. The island's main settlement of Waitangi is located in a small indentation in Petre Bay 's southern coast. Other significant settlements are Kaingaroa on
306-478: The northeast promontory, and Owenga on the south side of Hanson Bay. On the east coast is the even larger Hanson Bay , which stretches for the entire length of the island (35 kilometres (22 mi)). Much of the area between the bays is taken up by the large Te Whanga Lagoon , which drains to the sea to the east, into the southern half of Hanson Bay. This lagoon covers about 160 square kilometres (62 sq mi), and drains several small rivers that rise in
324-459: The realm of the winterless frost-free zone. There was no specific monsoon climate identifier in the original scheme, but Am was added later, with the same parameters as Köppen's (except that at least three months, rather than one, must have less than 60 mm average precipitation). BW and BS mean the same as in the Köppen scheme. However, a different formula is used to quantify the aridity threshold: 10( T − 10) + 3 P , with T equaling
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