Geography of Tonga

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Geography of Tonga
Tonga sm04.gif
Continent Pacific Ocean
Region Oceania
Coordinates 20°S175°W / 20°S 175°W / -20; -175
Area Ranked 174th
  Total747 km2 (288 sq mi)
Coastline419 km (260 mi)
Highest pointon Kao
1,033 metres (3,389 ft)
Lowest point Pacific Ocean
0 metres (0 ft)
Exclusive economic zone659,558 km2 (254,657 sq mi)
Tonga's position in the South Pacific. Tonga.jpg
Tonga's position in the South Pacific.

Located in Oceania, Tonga is a small archipelago in the South Pacific Ocean, center of south pacific and about two-thirds of the way from Hawaii to New Zealand. It has 169 islands, 36 of them inhabited, are divided into three main groups – Vava'u, Ha'apai, and Tongatapu – and cover an 800-kilometre (500-mile)-long north–south line. The total size is just 747 km2 (288 sq mi). Due to the spread out islands it has the 40th largest Exclusive Economic Zone of 659,558 km2 (254,657 sq mi).


The largest island, Tongatapu, on which the capital city of Nukuʻalofa is located, covers 257 square kilometres (99 sq mi). Geologically the Tongan islands are of two types: most have a limestone base formed from uplifted coral formations; others consist of limestone overlaying a volcanic base.


The climate is tropical with a distinct warm period (December–April), during which the temperatures rise above 32 °C (89.6 °F), and a cooler period (May–November), with temperatures rarely rising above 27 °C (80.6 °F). The temperature increases from 23 to 27 °C (73.4 to 80.6 °F), and the annual rainfall is from 1,700 to 2,970 millimetres (66.9 to 116.9 inches) as one moves from Tongatapu in the south to the more northerly islands closer to the Equator. The average wettest period is around March with on average 263 mm (10.4 in). [1] The average daily humidity is 80%. Cyclones can occur from October to April.


Though administratively divided into the three main island groups of Tongatapu, Ha'apai, and Vava'u (excluding the outlying islands), the Tonga archipelago is actually made of two geologically different parallel chains of islands.

The western islands, such as ʻAta (also known as Pylstaart island), Fonuafo'ou, Tofua, Kao, Lata'iki, Late, Fonualei, Toku, Niuatoputapu, and Tafahi, make up the Tongan Volcanic Arc and are all of volcanic origin. [2] They were created from the subduction of the western-moving Pacific plate under the Australia-India plate at the Tonga Trench. The Tongan Islands sit on the Australia-India plate just west of the Tonga Trench. These volcanoes are formed when materials in the descending Pacific plate heat and rise to the surface. There is only limited coral reef development on these islands, except for Niuatoputapu. [2]

The eastern islands are not volcanic and sit above the mostly submerged Tonga ridge that runs parallel to the Tongan Volcanic Arch and the Tongan Trench. Of these islands, only 'Eua has risen high enough to expose its underlying Eocene volcanic bedrock, the rest are either low coral limestone islands (Tongatapu, Vava'u, Lifuka) or sand cay islands ('Uoleva, 'Uiha). [2] These islands are surrounded by "a protective and resource-rich labyrinth of fringing, apron and off-shore barrier reefs" that have supported most of the human settlement in Tonga ever since the first Lapita People arrived circa 900 BCE. [2]

The Tongan Volcanic Arc has been important in supplying the islands on the Tonga ridge with an andesite tephra soil that has resulted in "an extremely rich soil capable of supporting a high-yield, short-fallow agricultural system." Also, the andesite/basalt from the volcanoes were initially used as "hammerstones, weaving weights, cooking stones, and decorative pebbles for grave decoration." [2] Tafahi island in the far north provided volcanic glass to initial human settlers. [2]

In December 2014 and January 2015, a volcanic island 1 km wide by 2 km long was created adjacent to the island of Hunga Ha'apai 65 kilometers northwest of Nuku'alofa. The volcanic eruption has built the new island to a height of 100 m composed of ash and large rock fragments. [3] In regards to volcanism, Tonga has moderate volcanic activity. Fonualei (elev. 180 m) has shown frequent activity in recent years, while Niuafo'ou (elev. 260 m), which last erupted in 1985, has forced evacuations; other historically active volcanoes include Late and Tofua. Natural hazards include earthquakes and volcanic activity at Fonuafo'ou (Falcon Shoal/Island) and Late'iki (Metis Shoal/Island).


Coastline in Tonga. Coastline in Tonga.jpg
Coastline in Tonga.

Geographic coordinates: 20°S175°W / 20°S 175°W / -20; -175

total:747 km2 (288 sq mi)
land:717 km2 (277 sq mi)
water:30 km2 (12 sq mi)

Coastline:419 km (260 mi)

Maritime claims:
continental shelf:200 m (656 ft) depth or to the depth of exploitation
exclusive economic zone:659,558 km2 (254,657 sq mi) and 200  nmi (370.4  km ; 230.2  mi )
territorial sea:12 nmi (22.2 km; 13.8 mi)

Elevation extremes:
lowest point: Pacific Ocean 0 m (0 ft)
highest point: unnamed location on Kao 1,033 m (3,389 ft)

Land use:
arable land: 21.33%
permanent crops: 14.67%
other: 64.00% (2011)

Environment - international agreements:
party to: Biodiversity, Climate Change, Climate Change Kyoto-Protocol, Desertification, Law of the Sea, Marine Dumping, Marine Life Conservation, Ozone Layer Protection, and Ship Pollution. [4]

Natural resources are fish and fertile soil. Current environmental issues are deforestation as more and more land is being cleared for agriculture and settlement; some damage to coral reefs from starfish and indiscriminate coral and shell collectors; and overhunting threatens native sea turtle populations.

Nuku Island Vava'u Nuku Island Vava'u.jpg
Nuku Island Vava'u

See also

Related Research Articles


Tongatapu is the main island of the Kingdom of Tonga and site of Tonga’s capital, Nukuʻalofa. It is located in Tonga's southern island group, to which it gives its name, and is the country's most populous island, with 74,611 residents (2016), 70.5% of the national population, on 260 square kilometres. Its maximum elevation is 28 metres above sea level. Tongatapu is Tonga's centre of government and the seat of its monarchy.


Niuafoʻou is the northernmost island in the kingdom of Tonga. It is a volcanic rim island with an area of 15 km2 (5.8 sq mi) and a population of 493. The Niuafoʻou language is spoken on the island.


Niuatoputapu is a high island in the island nation of Tonga, Pacific Ocean. Its highest point is 157 metres (515 ft), and its area is 16 square kilometres (6.2 sq mi). Its name means sacred island. Older European names for the island are Traitors island or Keppel island.


Vavaʻu is an island group, consisting of one large island and 40 smaller ones, in Tonga. It is part of Vavaʻu District, which includes several other individual islands. According to tradition, the Maui god created both Tongatapu and Vavaʻu, but put a little more effort into the former. Vavaʻu rises 204 metres (669 ft) above sea level at Mount Talau. The capital is Neiafu, situated at the Port of Refuge.


Haʻapai is a group of islands, islets, reefs, and shoals in the central part of the Kingdom of Tonga. It has a combined land area of 109.30 square kilometres (42.20 sq mi). The Tongatapu island group lies to its south, and the Vavaʻu group lies to its north. Seventeen of the Haʻapai islands are inhabited. Their combined population is 6,125. The Ha‘apai group’s highest point is Kao, which is almost 1,050 metres (3,440 ft) above sea level.

Radio Tonga is Tonga's main commercial radio station, founded in 1961 by Queen Salote Tupou III, and operating as a service of the Tonga Broadcasting Commission (TBC). Its slogan is "The Call of the Friendly Islands". Radio Tonga currently broadcasts services on three separate frequencies.


Tafahi is a small island in the north of the Tonga archipelago, in fact closer to Savaiʻi (Samoa) than to the main islands of Tonga. It is only 9 km (5.6 mi) north-northeast away from Niuatoputapu, and fishermen commute in small outboard motorboats almost daily between the two. The island has a population of no more than 40.

ʻEua Island in Tonga

ʻEua is an island in the kingdom of Tonga. It is close to Tongatapu, but forms a separate administrative division. It has an area of 87.44 km2 (33.76 sq mi), and a population in 2016 of 4,945 people.

Fonualei Island in Tonga

Fonualei is an uninhabited 5 km2 volcanic island close to Vavaʻu in the kingdom of Tonga. It was seen by Don Francisco Mourelle de la Rua on the La Princesa on 26 February 1781. He reported the island to be barren from eruptions, and called it for that reason Amargura.

Pumice raft

A pumice raft is a floating raft of pumice created by some eruptions of submarine volcanoes or coastal subaerial volcanoes.

Home Reef

Home Reef is an ephemeral island built by a submarine volcano whose top has repeatedly broken the surface and afterwards was eroded away by wave action. It is in the South Pacific, south of Late Island and southwest of Vava'u along the Tofua volcanic arc in Tonga.

Lifuka Island Airport

Lifuka Island Airport, also known as Salote Pilolevu Airport or Haʻapai Airport, is an airport on Lifuka in Tonga. The airport is located 5 km (3.1 mi) north of the capital Panga, and is only served domestically, roughly 40 minutes by flight to Tongatapu and 30 minutes to Vava'u. Taxis serve the airport, and services include a cafe inside the terminal.

Vavaʻu International Airport

Vavaʻu International Airport, also known as Lupepauʻu International Airport, is an airport in Vavaʻu, Tonga.

Hunga Tonga Volcano in Tonga

Hunga Tonga-Hunga Haʻapai is a volcanic island located about 30 kilometres south-southeast of Fonuafoʻou island in Tonga. The volcano is part of the highly active Tonga-Kermadec Islands volcanic arc, a subduction zone extending from New Zealand north-northeast to Fiji. It lies about 100 kilometres (62 mi) above a very active seismic zone. The island arc is formed at the convergent boundary where the Pacific Plate subducts under the Indo-Australian Plate.

2009 Tonga undersea volcanic eruption

The 2009 Tonga undersea volcanic eruption began on March 16, 2009, near the island of Hunga Tonga, approximately 11 kilometres (6.8 mi) from the Tongan capital of Tongatapu. The volcano is in a highly active volcanic region that represents a portion of the Pacific Ring of Fire. It is estimated that there are up to 36 undersea volcanoes clustered together in the area.

Though it is no longer practiced today, Tonga's ancient religion was practiced for over 2000 years. Missionaries arrived and persuaded King George Tupou I to convert to Christianity; he ordered and strictly enforced that all Tongans become Christian and no longer practice the ancient polytheistic religion with its supreme god Tangaloa.

The early history of Tonga covers the islands' settlement and the early Lapita culture through to the rise of the Tuʻi Tonga Empire.

Capricorn Seamount is a seamount in Tonga. It rises 4 kilometres (2.5 mi) to a depth of about 360 m (1,180 ft) and is capped off by a 15 km (9.3 mi) wide summit platform. It appears to be a submerged volcano of Miocene age that may be part of a volcanic chain with Niue. Capricorn Seamount is located on the eastern flank of the Tonga Trench and is in the process of breaking up; in turn the trench has been altered by the interaction with the downgoing seamount.

Tonga was the first South Pacific country to put a conservation programme in place with a series of national marine reserves. The country has four national parks which are administered by Forest Division, which falls under the Ministry of Environment and Climate Change.

Tongan tropical moist forests

The Tongan tropical moist forests is a tropical and subtropical moist broadleaf forests ecoregion that includes the Tonga archipelago and Niue.


  1. "Climate Guides - Plan Your Ideal Holiday Trip". Weather2Travel. Retrieved 2012-08-17.
  2. 1 2 3 4 5 6 David V. Burley, Tongan Archaeology and the Tongan Past, 2850-150 B.P, Journal of World Prehistory, Vol. 12, No. 3 (September 1998)
  3. "D news" . Retrieved January 21, 2015.
  4. "Archived copy" . Retrieved 2010-02-17.