Editing Southern Alps

{{short description|Mountain range on the South Island in New Zealand}}
{{other uses|Southern Alps (disambiguation)}}
{{Use New Zealand English|date=April 2024}}

{{Use dmy dates|date=October 2019}}
{{Infobox mountain
|name=Southern Alps / Kā Tiritiri o te Moana
|photo=South Island.jpg
|photo_caption=Snow highlights the mountain range in this satellite image
|location=[[South Island, New Zealand]]
|length_km=500
|highest=[[Aoraki / Mount Cook]]
|elevation_m=3724
|coordinates = {{coord|43|35|44.69|S|170|8|27.75|E|type:mountain_region:NZ|format=dms|display=inline}}
|range_coordinates = {{coord|43|30|S|170|30|E|type:mountain_region:NZ|format=dms|display=inline,title}}
}}
[[File:Southern Alps in Winter.jpg|thumb|Southern Alps in winter]]
The '''Southern Alps''' ({{Langx|mi|Kā Tiritiri o te Moana}}; officially '''Southern Alps / Kā Tiritiri o te Moana''')<ref name="Linz">{{LINZ|7442||21 December 2020}}</ref> are a [[mountain range]] extending along much of the length of [[New Zealand|New Zealand's]] [[South Island]], reaching its greatest elevations near the range's western side. The name "Southern Alps" generally refers to the entire range, although separate names are given to many of the smaller ranges that form part of it.

The range includes the South Island's '''Main Divide''', which separates the [[drainage basin|water catchments]] of the more heavily populated eastern side of the island from those on the west coast.<ref>{{cite book|last=Beck|first=Alan Copland|chapter-url=http://www.TeAra.govt.nz/en/1966/southern-alps/2|chapter=Topography|editor-first=A.H.|editor-last=McLintock|orig-year=1966|title=Te Ara – the Encyclopedia of New Zealand|year=2009|url-status=live|archive-url=https://web.archive.org/web/20121022051637/http://www.teara.govt.nz/en/1966/southern-alps/2|archive-date=22 October 2012}}</ref> Politically, the Main Divide forms the boundary between the [[Marlborough Region|Marlborough]], [[Canterbury Region|Canterbury]] and [[Otago]] [[regions of New Zealand|regions]] to the southeast and the [[Tasman Region|Tasman]] and [[West Coast, New Zealand|West Coast]] regions to the northwest.

==Names==
The [[Māori language|Māori]] name of the range is {{lang|mi|Kā Tiritiri o te Moana}}, meaning "the [[Fata Morgana (mirage)|Mirage]] of the Ocean".<ref>{{Cite journal|title=Māui at Mahitahi|last=Wallace|first=Susan|journal=School Journal|pages=32–3|publisher=[[Ministry of Education (New Zealand)|Ministry of Education New Zealand]]|date=Jun 2022}}</ref><ref name="Linz"/>

The [[English people|English]] explorer [[James Cook]] bestowed the name ''Southern Alps'' on 23 March 1770, admiring their "prodigious height".<ref name="Naming">{{ReedPlacenames1975}} p. 384.</ref> They had previously been noted by [[Abel Tasman]] in 1642, whose description of the South Island's west coast is often translated as "a land uplifted high".<ref name="Tasman">Orsman, H. and Moore, J. (eds) (1988) ''Heinemann Dictionary of New Zealand Quotations'', [[Heinemann (book publisher)|Heinemann]], Page 629.</ref>

Following the passage of the [[Ngāi Tahu Claims Settlement Act 1998]], the official name of the range was updated to ''Southern Alps / Kā Tiritiri o te Moana''.<ref>
{{cite web | url=http://www.legislation.govt.nz/act/public/1998/0097/10.0/DLM431335.html 
| title=Ngāi Tahu Claims Settlement Act 1998 
| access-date=30 October 2018}}
</ref>

==Geography==
[[File:Mountains in New Zealand.jpg|thumb|left|upright|View of the western Southern Alps from [[State Highway 6 (New Zealand)|State Highway 6]] near [[Hari Hari]], [[Westland District|Westland]]]]
The Southern Alps run approximately 500&nbsp;km<ref>{{cite web|url=http://www.teara.govt.nz/en/mountains/page-1|title=1. – Mountains – Te Ara: The Encyclopedia of New Zealand|first=New Zealand Ministry for Culture and Heritage Te Manatu|last=Taonga|website=www.teara.govt.nz|url-status=live|archive-url=https://web.archive.org/web/20150506065311/http://www.teara.govt.nz/en/mountains/page-1|archive-date=6 May 2015}}</ref> northeast to southwest. Its tallest peak is [[Aoraki / Mount Cook]], the highest point in New Zealand at {{convert|3724|m|ft}}. The Southern Alps include sixteen other points that exceed {{convert|3000|m|ft|}} in height (see [[List of mountains of New Zealand by height|NZ mountains by height]]). The mountain ranges are bisected by glacial valleys, many of which are infilled with glacial lakes on the eastern side including [[Lake Coleridge]] in the north and [[Lake Wakatipu]] in [[Otago]] in the south. According to an inventory conducted in the late 1970s, the Southern Alps contained over 3,000 [[glacier]]s larger than one hectare,<ref name="Chinn">{{cite journal |author=Chinn TJ |year=2001 |url=http://www.hydrologynz.org.nz/downloads/20071015-094857-JoHNZ_2001_v40_2_Chinn.pdf |title=Distribution of the glacial water resources of New Zealand |journal=Journal of Hydrology |location=New Zealand |volume=40 |issue=2 |pages=139–187 |url-status=dead |archive-url=https://web.archive.org/web/20081016102753/http://www.hydrologynz.org.nz/downloads/20071015-094857-JoHNZ_2001_v40_2_Chinn.pdf |archive-date=16 October 2008  }}</ref> the longest of which – the [[Tasman Glacier]] – is {{convert|23.5|km|mi}} in length which has retreated from a recent maximum of {{convert|29|km|mi}} in the 1960s.<ref name="glaciers">{{cite book |editor=Lambert M |year=1989 |title=Air New Zealand Almanack |location=Wellington |publisher=New Zealand Press Association |page=165}}</ref><ref name="Glacier2017">{{cite news|url=http://www.stuff.co.nz/environment/89403443/when-the-worlds-glaciers-shrunk-new-zealands-grew-bigger|title=When the world's glaciers shrunk, New Zealand's grew bigger|work=[[Stuff (website)|Stuff]]|author=Charlie Mitchell|date=15 February 2017|access-date=15 February 2017}}</ref>

Settlements include Maruia Springs, a spa near [[Lewis Pass]], the town of [[Arthur's Pass]], and [[Mount Cook Village]].

Major crossings of the Southern Alps in the New Zealand road network include [[Lewis Pass]] ({{NZSH|7}}), [[Arthur's Pass (mountain pass)|Arthur's Pass]] ({{NZSH|73}}), [[Haast Pass]] ({{NZSH|6}}), and the road to [[Milford Sound (village)|Milford Sound]] ({{NZSH|94}}).

===Climate===
New Zealand has a humid maritime, temperate climate with the Southern Alps lying perpendicular to the prevailing westerly flow of air. Annual precipitation varies greatly across the range, from {{convert|3000|mm}} at the [[West Coast, New Zealand|West Coast]], {{convert|15000|mm}} close to the Main Divide, to {{convert|1000|mm}} {{convert|30|km}} east of the Main Divide.<ref>{{cite report |publisher=NIWA |author1=Willsman AP |author2=Chinn TJ |author3=Hendrikx J |author4=Lorrey A |year=2010 |url=https://www.niwa.co.nz/sites/niwa.co.nz/files/import/attachments/NIWA-New-Zealand-Glacier-Monitoring-End-of-Summer-Snowline-Survey-2010.pdf |title=New Zealand Glacier Monitoring: End of Summer Snowline Survey 2010 |location=New Zealand |url-status=live |archive-url=https://web.archive.org/web/20171029065258/https://www.niwa.co.nz/sites/niwa.co.nz/files/import/attachments/NIWA-New-Zealand-Glacier-Monitoring-End-of-Summer-Snowline-Survey-2010.pdf |archive-date=29 October 2017  }}</ref> This high precipitation aids the growth of [[glacier]]s above the [[snow line]]. Large glaciers and snowfields can be found west of or on the Main Divide, with smaller glaciers farther east (See [[Glaciers of New Zealand]]).

Because of its orientation perpendicular to the prevailing westerly winds, the range creates excellent wave soaring conditions for [[Glider aircraft|glider]] pilots. The town of [[Omarama]], in the lee of the mountains, has gained an international reputation for its gliding conditions. The prevailing westerlies also create a weather pattern known as the ''[[Nor'west arch]]'', in which moist air is pushed up over the mountains, forming an arch of cloud in an otherwise blue sky. This weather pattern is frequently visible in summer across [[Canterbury Region|Canterbury]] and [[North Otago]]. The 'Nor'wester' is a [[foehn wind]] similar to the [[Chinook wind|Chinook]] of Canada, where mountain ranges in the path of prevailing moisture laden winds force air upwards, thus cooling the air and condensing the moisture to rain, producing hot dry winds in the descending air lee of the mountains.

==Geology==
[[File:Mount Cook 2.jpg|thumb|right| View of [[Aoraki / Mount Cook]], the highest peak, from the [[Hooker Valley Track]]]]
[[Image:Alpine Fault SRTM (vertical).jpg|<!--135px-->135px|right|thumb|Shaded and colored image from the [[Shuttle Radar Topography Mission]]—shows an [[topology|elevation model]] of New Zealand's [[Alpine Fault]] running about 500&nbsp;km (300&nbsp;mi) long. The escarpment is flanked by a chain of hills squeezed between the [[Fault (geology)|fault]] and the mountains of the Southern Alps. Northeast is towards the top.]]

The Southern Alps lie along a geological [[plate boundary]], part of the [[Pacific Ring of Fire]], with the [[Pacific Plate]] to the southeast pushing westward and colliding with the northward-moving [[Indo-Australian Plate]] to the northwest.<ref>{{cite book |last1=Campbell |first1=Hamish |last2=Hutching |first2=Gerard |title=In search of ancient New Zealand |date=2007 |publisher=[[Penguin Books|Penguin]]; [[GNS Science]] |location=[[North Shore, N.Z.]] |isbn=978-0-143-02088-2 |page=35}}</ref>  Over the last 45 million years, the collision has pushed up a 20&nbsp;km thickness of rocks on the Pacific Plate to form the Alps, although much of this has been eroded away. Uplift has been most rapid during the last 5&nbsp;million years, and the mountains continue to be raised today by [[tectonics|tectonic]] pressure, causing earthquakes on the [[Alpine Fault]] and other nearby faults. Despite the substantial uplift, most of the relative motion along the Alpine Fault is [[Fault (geology)#Strike-slip faults|transverse]], not [[Fault (geology)#Dip-slip faults|vertical]].{{sfn |Campbell|Hutching|2007|pp=204–205}} However, significant dip-slip occurs on the plate boundary to the north and east of the North Island, in the [[Hikurangi Trough]] and [[Kermadec Trench]]. The transfer of motion from strike-slip on the Alpine Fault to dip-slip motion at these subduction zones to the north creates the [[Marlborough Fault System]], which has resulted in significant uplift in the region.

In 2017 a large international team of scientists reported they had discovered beneath [[Whataroa]], a small township on the Alpine Fault, "extreme" hydrothermal activity which "could be commercially very significant".<ref name="Sutherland">{{cite journal |last1=Sutherland |first1=Rupert |last2=Townend |first2=John |last3=Toy |first3=Virginia |last4=Upton |first4=Phaedra |last5=Coussens |first5=Jamie |last6=Allen |first6=Michael |author7=60 others |name-list-style=and |title=Extreme hydrothermal conditions at an active plate-bounding fault |journal=Nature |date=June 2017 |volume=546 |issue=7656 |pages=137–140 |doi=10.1038/nature22355 |pmid=28514440 |bibcode=2017Natur.546..137S |hdl=1874/351355 |s2cid=205256017 |url=https://www.researchgate.net/publication/317005994 |access-date=6 February 2021}}</ref><ref>{{cite news |last1=Elder |first1=Vaughan |title=Geothermal discovery on West Coast |url=https://www.odt.co.nz/regions/west-coast/geothermal-discovery-west-coast |access-date=6 February 2021 |work=[[Otago Daily Times]] |date=18 May 2017 |archive-url=https://web.archive.org/web/20180314174145/https://www.odt.co.nz/regions/west-coast/geothermal-discovery-west-coast |archive-date=14 March 2018 |page=|url-status=live |language=en |quote=''&thinsp;'Nobody on our team, or any of the scientists who reviewed our plans, predicted that it would be so hot down there.  This geothermal activity may sound alarming but it is a wonderful scientific finding that could be commercially very significant for New Zealand.'&thinsp;''}}</ref>

==Flora==
{{main|Southland montane grasslands}}
The mountains are rich in flora with about 25% of the country's plant species being found above the treeline in [[alpine plant]] habitats and grassland with [[mountain beech]] forest at lower elevations (of the eastern side but not in [[Westland District|Westland]]). The cold windswept slopes above the treeline are covered with areas of [[fellfield]]. To the east, the Alps descend to the [[Canterbury-Otago tussock grasslands]]. Plants adapted to the alpine conditions include woody shrubs like ''[[Hebe (plant)|Hebe]]'', ''[[Dracophyllum]]'', and ''[[Coprosma]]'', the conifer [[Podocarpus nivalis|snow totara]] ''(Podocarpus nivalis)'' and ''[[Carex]]'' sedge grasses.<ref>{{WWF ecoregion|id=aa1003|name=South Island montane grasslands}}</ref>

==Fauna==
Wildlife of the mountains includes the endemic [[New Zealand rockwren|rock wren]] ''(Xenicus gilviventris)''. There are also a number of endemic insects adapted to these high altitudes, like flies, moths, beetles, bees, and the [[mountain stone wētā]], which can freeze solid over winter to survive the [[Alpine climate|alpine]] conditions. The beech forests of the lower elevations are important habitat for several birds, such as the [[great spotted kiwi]] ''(Apteryx haastii)'', the South Island [[New Zealand kaka|kākā]] ''(Nestor meridionalis meridionalis)'', and the [[orange-fronted kākāriki]] ''(Cyanoramphus malherbi)''. The [[kea]] can be found in the forested foothills as well as higher, colder elevations. It is the world's only alpine [[parrot]], and was once hunted as a pest.

==Threats and preservation==
The mountains are inaccessible and retain their natural vegetation. A large proportion of the range is well protected by national parks—notably the [[Westland Tai Poutini National Park]], [[Mount Aspiring National Park]], and [[Aoraki / Mount Cook National Park]]—or by [[Protected areas of New Zealand|protected areas]] such as [[Lake Sumner Forest Park]]. Indigenous plant life is affected by introduced animals such as [[red deer]] (''Cervus elaphus''), [[chamois]] (''Rupicapra rupicapra''), and [[Himalayan tahr]] (''Hemitragus jemlahicus''), all of which have at times been targeted for culling. Likewise, native birds and reptiles are vulnerable to introduced predators.

==Panoramic view==
{{Wide image|Southern Alps from Hamilton Peak.jpg|2000px|Panoramic winter view from the summit of Hamilton Peak in the [[Craigieburn Range]].}}

==References==
{{Reflist}}

== External links ==
{{commons and category|Southern Alps}}
* {{cite web|url= http://nzetc.victoria.ac.nz//tm/scholarly/tei-McCExpl-t1-body-d16.html |title= The Exploration of the Southern Alps (from 1940 book) |publisher=NZETC }}

{{Westland landforms}}

[[Category:Southern Alps| ]]
[[Category:Mountain ranges of Fiordland]]
[[Category:Mountain ranges of the Canterbury Region]]
[[Category:Mountain ranges of the West Coast Region]]
[[Category:Montane grasslands and shrublands]]