Mount Waialeale
Encyclopedia
Mount Waialeale at an elevation of 5148 feet (1,569.1 m), is a shield volcano
and the second highest point on the island of Kauai
in the Hawaiian Islands
. Averaging more than 452 inches (11,480.8 mm) of rain a year since 1912, with a record 683 inches (17,348.2 mm) in 1982, its summit is one of the rainiest spots on earth.
(Koppen
Af), with substantial rainfall throughout the course of the year. quotes 11684 millimetres (460 in) per year figure as being the 1912-45 average, an average that quite possibly will have changed since then, while The National Climatic Data Center
quotes this figure as a 30 year average. The Weather Network and The Guinness Book of Weather Records quotes 11455 millimetres (451 in) rain per year, while quotes 11,680 millimetres (460 in, 12 m) as the average annual rainfall at Mount Waialeale and claims 13000 millimetres (511.8 in) falls here. Similarly, The Weather Network
and the Guinness Book of Weather Records quote 335 days with rain here while suggests that rain falls on an incredible 360 days per year here.
The local tourist industry of Waialeale has promoted it as the wettest spot, although the 38-year average at Mawsynram
, Meghalaya
, India
is higher at 467.4 inches (11,872 mm). Both Mawsynram
and Cherrapunji
in Meghalaya are recognized by the Guinness Book of World Records as having higher average rainfall. Mawsynram's rainfall is concentrated in the monsoon
season, while the rain at Waiʻaleʻale is more evenly distributed through the year.
A number of rare local plant species are named for this mountain, including Astelia waialealae
, Melicope waialealae
, and the endemic Dubautia waialealae
.
Shield volcano
A shield volcano is a type of volcano usually built almost entirely of fluid lava flows. They are named for their large size and low profile, resembling a warrior's shield. This is caused by the highly fluid lava they erupt, which travels farther than lava erupted from more explosive volcanoes...
and the second highest point on the island of Kauai
Kauai
Kauai or Kauai, known as Tauai in the ancient Kaua'i dialect, is geologically the oldest of the main Hawaiian Islands. With an area of , it is the fourth largest of the main islands in the Hawaiian archipelago, and the 21st largest island in the United States. Known also as the "Garden Isle",...
in the Hawaiian Islands
Hawaiian Islands
The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll...
. Averaging more than 452 inches (11,480.8 mm) of rain a year since 1912, with a record 683 inches (17,348.2 mm) in 1982, its summit is one of the rainiest spots on earth.
Climate and Rainfall Statistics
The summit of Waialeale features a tropical rainforest climateTropical rainforest climate
A tropical rainforest climate, also known as an equatorial climate, is a tropical climate usually found along the equator...
(Koppen
Köppen climate classification
The Köppen climate classification is one of the most widely used climate classification systems. It was first published by Crimea German climatologist Wladimir Köppen in 1884, with several later modifications by Köppen himself, notably in 1918 and 1936...
Af), with substantial rainfall throughout the course of the year. quotes 11684 millimetres (460 in) per year figure as being the 1912-45 average, an average that quite possibly will have changed since then, while The National Climatic Data Center
National Climatic Data Center
The United States National Climatic Data Center in Asheville, North Carolina is the world's largest active archive of weather data. The center became established in late 1951, with the move into the new facility occurring in early 1952....
quotes this figure as a 30 year average. The Weather Network and The Guinness Book of Weather Records quotes 11455 millimetres (451 in) rain per year, while quotes 11,680 millimetres (460 in, 12 m) as the average annual rainfall at Mount Waialeale and claims 13000 millimetres (511.8 in) falls here. Similarly, The Weather Network
The Weather Network
The Weather Network is a Canadian English language Category A specialty channel that broadcasts weather-related news and information 24 hours a day....
and the Guinness Book of Weather Records quote 335 days with rain here while suggests that rain falls on an incredible 360 days per year here.
The local tourist industry of Waialeale has promoted it as the wettest spot, although the 38-year average at Mawsynram
Mawsynram
Mawsynram is a village in the East Khasi Hills district of Meghalaya state in north-eastern India, 56 kilometers from Shillong. It is reportedly the wettest place on Earth, with an annual rainfall of...
, Meghalaya
Meghalaya
Meghalaya is a state in north-eastern India. The word "Meghalaya" literally means the Abode of Clouds in Sanskrit and other Indic languages. Meghalaya is a hilly strip in the eastern part of the country about 300 km long and 100 km wide, with a total area of about 8,700 sq mi . The...
, India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
is higher at 467.4 inches (11,872 mm). Both Mawsynram
Mawsynram
Mawsynram is a village in the East Khasi Hills district of Meghalaya state in north-eastern India, 56 kilometers from Shillong. It is reportedly the wettest place on Earth, with an annual rainfall of...
and Cherrapunji
Cherrapunji
Cherrapunji , is a subdivisional town in the East Khasi Hills district in the Indian state of Meghalaya. It is credited as being the second wettest place on Earth...
in Meghalaya are recognized by the Guinness Book of World Records as having higher average rainfall. Mawsynram's rainfall is concentrated in the monsoon
Monsoon
Monsoon is traditionally defined as a seasonal reversing wind accompanied by corresponding changes in precipitation, but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with the asymmetric heating of land and sea...
season, while the rain at Waiʻaleʻale is more evenly distributed through the year.
Causes
Several factors give the summit of Waialeale more potential to create precipitation than the rest of the island chain:- Its northern position relative to the main Hawaiian Islands provides more exposure to frontal systems that bring rain during the winter.
- It has a relatively round and regular conical shape, exposing all sides of its peak to winds and the moisture that they carry.
- Its peak lies just below the so-called trade windTrade windThe trade winds are the prevailing pattern of easterly surface winds found in the tropics, within the lower portion of the Earth's atmosphere, in the lower section of the troposphere near the Earth's equator...
inversion layer of 6000 feet (1,828.8 m), above which trade-wind-produced clouds cannot rise. - And most importantly, the steep cliffs cause the moisture-laden air to rise rapidly - over 3000 feet (914.4 m) in less than 0.5 mile (0.80467 km) - and drop a large portion of its rain in one spot, as opposed to spreading the rain out over a larger area if the slope were more gradual.
Ecology
The great rainfall in the area produces the Alakai Wilderness Preserve, a large boggy area that is home to many rare plants. The ground is so wet that although trails exist, access by foot to the Waiʻaleʻale area is extremely difficult.A number of rare local plant species are named for this mountain, including Astelia waialealae
Astelia waialealae
Astelia waialealae is a rare species of plant in the Asteliaceae family that is endemic to the island of Kauai of the state of Hawaii in United States. It inhabits montane bogs within the vicinity of the Alakai Swamp on the island's central plateau. A. waialealae is threatened by habitat loss and...
, Melicope waialealae
Melicope waialealae
Melicope waialealae is a species of flowering plant in the Rutaceae family that is endemic to the island of Kauai in Hawaii.-Source:* World Conservation Monitoring Centre 1998. . Downloaded on 12 March 2011....
, and the endemic Dubautia waialealae
Dubautia waialealae
Dubautia waialealae is a rare species of flowering plant in the aster family known by the common name Wai'ale'ale dubautia. It is endemic to Hawaii, where it is known only from Mount Waiʻaleʻale on Kauai. One individual was seen outside the range, about 14 kilometers away, but this plant is now...
.