Overview New Zealand is located in the
South Pacific Ocean at , near the centre of the
water hemisphere. It is a long and narrow country, extending along its north-north-east axis with a maximum width of . The land size of makes it the sixth-largest island country. New Zealand consists of a
large number of islands, estimated around 600. The islands give it of
coastline and extensive marine resources. New Zealand claims the ninth largest
exclusive economic zone in the world, covering , more than 15 times its land area. The
South Island is the largest land mass of New Zealand, and is the
12th-largest island in the world. The island is divided along its length by the
Southern Alps. The east side of the island has the
Canterbury Plains while the
West Coast is famous for its rough coastlines, high rainfall, very high proportion of native
bush (forest), and
glaciers. The
North Island is the second-largest island, and the 14th-largest in the world. It is separated from the South Island by the
Cook Strait, with the shortest distance being . The North Island is less mountainous than the South Island, The North Island has many isolated volcanic peaks. Besides the North and South Islands, the five largest inhabited islands are
Stewart Island ( due south of the South Island),
Chatham Island (
Wharekauri in
Māori or
Rēkohu in
Moriori) (some east of the South Island),
Great Barrier Island (in the
Hauraki Gulf),
Rangitoto ki te Tonga / D'Urville Island (in the
Marlborough Sounds) and
Waiheke Island (about from central
Auckland).
Extreme points The phrase "From Cape Reinga to The Bluff" is frequently used within New Zealand to refer to the extent of the whole country.
Cape Reinga / Te Rerenga Wairua is the northwesternmost tip of the
Aupōuri Peninsula, at the northern end of the North Island.
Bluff is
Invercargill's port, located near the southern tip of the South Island, below the
46th parallel south. However, the extreme points of New Zealand are in fact located in several
outlying islands. The points that are farther north, south, east or west than any other location in New Zealand are as follows: The northern half of the South Island corresponds to
Galicia and northern Portugal. In Europe the term "Antipodes" is often used to refer to New Zealand and Australia (and sometimes other South Pacific areas), and "
Antipodeans" to their inhabitants.
Geology , the submerged continent, and the two tectonic plates New Zealand is part of
Zealandia, a
microcontinent nearly half the size of
Australia that gradually submerged after breaking away from the
Gondwana supercontinent. Zealandia extends a significant distance east into the Pacific Ocean and south towards Antarctica. It also extends towards Australia in the north-west. This submerged continent is dotted with topographic highs that sometimes form islands. Some of these, such as the main islands (North and South), Stewart Island, New Caledonia, and the Chatham Islands, are settled. Other smaller islands are eco-sanctuaries with carefully controlled access. margins. The caldera they surround was formed during the huge
Oruanui eruption. The New Zealand land mass has been
uplifted due to
transpressional
tectonics between the
Indo-Australian plate and
Pacific plates (these two plates are grinding together with one riding up and over the other). This is the cause of New Zealand's numerous earthquakes. To the east of the North Island the Pacific plate is forced under the Indo-Australian plate. The North Island of New Zealand has widespread back-arc volcanism as a result of this
subduction. There are many large volcanoes with relatively frequent eruptions. There are also several very large
calderas, with the most obvious forming
Lake Taupō. Taupō has a history of incredibly powerful eruptions, with the
Oruanui eruption 26,500 years ago ejecting of material and causing the downward collapse of several hundred square kilometres to form the lake. The
most recent eruption occurred and ejected at least of material, and has been correlated with red skies seen at the time in
Rome and
China. The associated geothermal energy from this volcanic area is used in numerous
hydrothermal power plants. Some volcanic places are also famous tourist destinations, such as the
Rotorua geysers. The subduction direction is reversed through the South Island, with the Indo-Australian plate forced under the Pacific plate. The transition between these two different styles of continental collision occurs through the top of the South Island. This area has significant uplift and many
active faults; large earthquakes are frequent occurrences here. The most powerful in recent history, the M8.3
Wairarapa earthquake, occurred in 1855. This earthquake generated more than of vertical uplift in places, and caused a localised tsunami. Fortunately casualties were low due to the sparse settlement of the region. In 2013, the area was rattled by the M6.5
Seddon earthquake, but this caused little damage and no injuries. New Zealand's
capital city,
Wellington is situated in the centre of this region. The subduction of the Indo-Australian plate drives rapid uplift in the centre of the South Island (approx. per year). This uplift forms the Southern Alps. These roughly divide the island, with a narrow wet strip to the west and wide and dry plains to the east. The resulting
orographic rainfall enables the
hydroelectric generation of most of the electricity in New Zealand. The rapid uplift and high
erosion rates within the Southern Alps combine to expose high grade
greenschist to
amphibolite facies rocks, including the gemstone
pounamu. Geologists visiting the West Coast can easily access high-grade
metamorphic rocks and
mylonites associated with the Alpine Fault, and in certain places can stand astride the fault trace of an active plate boundary. The South Island also has two major
goldfields in
Otago and the
West Coast. is dominated by steep, glacier-carved valleys. To the south of New Zealand the Indo-Australian plate is subducting under the Pacific plate, and this is beginning to result in
back-arc volcanism. The youngest (geologically speaking) volcanism in the South Island occurred in this region, forming the
Solander Islands (<2 million years old). This region is dominated by the rugged and relatively untouched
Fiordland, an area of flooded glacially carved valleys with little human settlement.
Mountains, volcanoes and glaciers , as seen from
Hooker Valley The South Island is much more mountainous than the North, but shows fewer manifestations of recent volcanic activity. There are 18 peaks of more than in the Southern Alps, which stretch for down the South Island. The closest mountains surpassing it in elevation are found not in Australia, but in
New Guinea and Antarctica. As well as the towering peaks, the Southern Alps include huge glaciers such as
Franz Josef and
Fox. The country's highest mountain is
Aoraki / Mount Cook; its height since 2014 is listed as (down from before December 1991, due to a rockslide and subsequent erosion). The second highest peak is
Mount Tasman, with a height of . The
North Island Volcanic Plateau covers much of central North Island with volcanoes,
lava plateaus, and
crater lakes. The three highest volcanoes are
Mount Ruapehu (),
Mount Taranaki () and
Mount Ngauruhoe (). Ruapehu's major eruptions have historically been about 50 years apart, in 1895, 1945 and 1995–1996. The
1886 eruption of Mount Tarawera, located near
Rotorua, was New Zealand's largest and deadliest eruption in the last 200 years, killing over 100 people. Another long chain of mountains runs through the North Island, from Wellington to East Cape. The ranges include
Tararua and
Kaimanawa. The lower mountain slopes are covered in native forest. Above this are shrubs, and then
tussock grasses.
Alpine tundra consists of cushion plants and
herbfields; many of these plants have white and yellow flowers.
Caves New Zealand's cave systems have three main origins, the chemical weathering of limestone by water (
karst),
lava caves and erosion by waves (
sea caves). Therefore, the distribution of limestone, marble (
metamorphosed limestone) and volcanoes defines the location of caves in inland New Zealand. The main regions of karst topography are the
Waitomo District and
Takaka Hill in the
Tasman District. Other notable locations are on the
West Coast (
Punakaiki),
Hawke's Bay and
Fiordland. Lava caves (
lava tubes) usually form in
pāhoehoe lava flows, which are less viscous and typical formed from
basalt. When an eruption occurs the outer layer of the lava flow hardens, while the interior remains liquid. The liquid lava flows out as it is insulated by the hardened crust above. These caves are found where there are relatively recent basaltic volcanoes in New Zealand, such as the
Auckland volcanic field particularly on
Rangitoto,
Mount Eden and
Matukutūruru. The distribution of sea caves is more sporadic, with their location and orientation being controlled by weakness in the underlying rock. As cave systems take many thousands of years to develop they can not be isolated from the water that formed them, whether through change in sea level or groundwater flow. If as a cave grows it breaks through to the surface somewhere else it becomes a
natural arch, like the
Ōpārara Basin Arches near
Karamea.
Rivers and lakes The proportion of New Zealand's area (excluding
estuaries) covered by rivers, lakes and ponds, based on figures from the New Zealand Land Cover Database, is (357526 + 81936) / (26821559 – 92499–26033 – 19216) = 1.6%. If estuarine open water, mangroves, and
herbaceous saline vegetation are included, the figure is 2.2%. New Zealand's rivers feature
hundreds of waterfalls; the most visited set of waterfalls are the
Huka Falls that drain Lake Taupō. Lake Taupō, located near the centre of the North Island, is the largest lake by surface area in the country. It lies in a
caldera created by the
Oruanui eruption, the largest eruption in the world in the past 70,000 years. There are 3,820 lakes with a surface area larger than one
hectare. Many lakes have been used as reservoirs for
hydroelectric projects.
Coastal wetlands Wetlands support the greatest concentration of wildlife out of any other habitat. New Zealand has six sites covering almost that are included in the
List of Wetlands of International Importance (
Ramsar sites), including the
Whangamarino Wetland. A 2016 global remote sensing analysis suggested that there were of
tidal flats in New Zealand, making it the 29th ranked country in terms of tidal flat area.
Climate The main geographic factors that influence New Zealand's climate are the temperate
latitude, with
prevailing westerly winds; the
oceanic environment; and the mountains, especially the Southern Alps. The climate is mostly temperate with mean temperatures ranging from in the South Island to in the North Island. January and February are the warmest months, July the coldest. New Zealand does not have a large temperature range, apart from central Otago, but the weather can change rapidly and unexpectedly. Near
subtropical conditions are experienced in
Northland. Most settled, lowland areas of the country have between of
rainfall, with the most rain along the west coast of the South Island and the least on the east coast of the South Island and interior basins, predominantly on the
Canterbury Plains and the Central Otago Basin (about ).
Christchurch is the driest city, receiving about of rain PA, while
Hamilton is the wettest, receiving more than twice that amount at PA, followed closely by Auckland. The wettest area by far is the rugged Fiordland region, in the south-west of the South Island, which has between of rain PA, with up to 15,000 mm in isolated valleys, amongst the highest recorded rainfalls in the world. , Wellington, in summer The
UV index can be very high and extreme in the hottest times of the year in the north of the North Island. This is partly due to the country's relatively little
air pollution compared to many other countries and the high
sunshine hours. New Zealand has very high sunshine hours with most areas receiving over 2000 hours per year. The sunniest areas are Nelson/Marlborough and the Bay of Plenty with 2,400 hours per year. The table below lists climate normals for the warmest and coldest months in New Zealand's six largest cities. North Island cities are generally warmest in February. South Island cities are warmest in January. The combined
effects of
climate change in New Zealand will result in a multitude of irreversible impacts; by the end of this century New Zealand will experience higher rainfalls, more frequent extreme weather events and higher temperatures. In 2021, the
Ministry for the Environment estimated that New Zealand's gross emissions were 0.17% of the world's total gross
greenhouse gas emissions. However, on a per capita basis, New Zealand is a significant emitter, the sixth highest within the
Annex I countries, whereas on absolute gross emissions New Zealand is ranked as the 24th highest emitter. ==Human geography==