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Cyclone Val

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161-586: Severe Tropical Cyclone Val (also known as Hurricane Val ) was considered to be the worst tropical cyclone to affect the Samoan Islands since the 1889 Apia cyclone . The system was first identified during the opening days of December 1991, as a small circulation, within the Intertropical Convergence Zone to the north of Tokelau. Over the next few days, the system moved westwards towards Rotuma and Tuvalu and gradually developed further, before it

322-424: A Royal New Zealand Air Force Orion to conduct an aerial reconnaissance flight during December 8, however, this was postponed until December 10, due to the weather conditions over the Samoan Islands. They also planned to send a frigate to Samoa with relief supplies on board during December 10, as it was thought that the airport might have to be closed for a little while. Tropical cyclone A tropical cyclone

483-518: A Tropical Cyclone Warning Centre by the World Meteorological Organization 's (WMO) tropical cyclone programme. These warning centers issue advisories which provide basic information and cover a systems present, forecast position, movement and intensity, in their designated areas of responsibility. Meteorological services around the world are generally responsible for issuing warnings for their own country. There are exceptions, as

644-416: A 1.5 degree warming lead to "increased proportion of and peak wind speeds of intense tropical cyclones". We can say with medium confidence that regional impacts of further warming include more intense tropical cyclones and/or extratropical storms. Climate change can affect tropical cyclones in a variety of ways: an intensification of rainfall and wind speed, a decrease in overall frequency, an increase in

805-444: A 2019 review paper show a future increase of rainfall rates. Additional sea level rise will increase storm surge levels. It is plausible that extreme wind waves see an increase as a consequence of changes in tropical cyclones, further exacerbating storm surge dangers to coastal communities. The compounding effects from floods, storm surge, and terrestrial flooding (rivers) are projected to increase due to global warming . There

966-465: A change in the character of many articles of manufacture. The warclubs and spears were of uncommon form, and neatly made. On 24 October, Wilkes writes, that the Porpoise arrived back at Sapapaliʻi village, having been gone nine days. The team met paramount chief Malietoa and his son at the village. With local guides Dr Pickering had travelled some way into the interior of the island, reaching one side of

1127-486: A chiefs' council ( fono o matai ) in each village. The fono o matai carry out 'village law' and socio-political governance based on their traditional authority and faʻa Samoa. The authority of the matai is balanced against central government, the Malo. Most of the matai are males, however, the women in each village also have a voice in domestic affairs through the women's committees. The main government administration offices of

1288-590: A circle, whirling round their central clear eye , with their surface winds blowing counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere . The opposite direction of circulation is due to the Coriolis effect . Tropical cyclones tend to develop during the summer, but have been noted in nearly every month in most tropical cyclone basins . Tropical cyclones on either side of

1449-546: A convective rainband and rain squalls that appeared on satellite imagery at the time. Gale-force winds were also reported over Pukapuka and nearby islands in the Northern Cook Islands during December 11. Within the Cook Islands, damages to crops and infrastructure were reported, with total damages estimated at $ 1 million NZD (US$ 544 thousand). The government of the Cook Islands also asked for money to repair

1610-405: A flow of warm, moist, rapidly rising air, which starts to rotate cyclonically as it interacts with the rotation of the earth. Several factors are required for these thunderstorms to develop further, including sea surface temperatures of around 27 °C (81 °F) and low vertical wind shear surrounding the system, atmospheric instability, high humidity in the lower to middle levels of

1771-501: A gale warning as it had become apparent that the system would impact the American territory, before the warning was upgraded to a hurricane warning the following day as Val moved closer to the archipelago. On December 8, the FMS downgraded the warning to a gale warning as the threat of Val passing near the territory decreased since the system had started to move southwards and now directly threatened

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1932-506: A higher intensity. Most tropical cyclones that experience rapid intensification are traversing regions of high ocean heat content rather than lower values. High ocean heat content values can help to offset the oceanic cooling caused by the passage of a tropical cyclone, limiting the effect this cooling has on the storm. Faster-moving systems are able to intensify to higher intensities with lower ocean heat content values. Slower-moving systems require higher values of ocean heat content to achieve

2093-460: A large number of forecasting centers, uses infrared geostationary satellite imagery and an algorithm based upon the Dvorak technique to assess the intensity of tropical cyclones. The ADT has a number of differences from the conventional Dvorak technique, including changes to intensity constraint rules and the usage of microwave imagery to base a system's intensity upon its internal structure, which prevents

2254-464: A large role in both the classification of a tropical cyclone and the determination of its intensity. Used in warning centers, the method was developed by Vernon Dvorak in the 1970s, and uses both visible and infrared satellite imagery in the assessment of tropical cyclone intensity. The Dvorak technique uses a scale of "T-numbers", scaling in increments of 0.5 from T1.0 to T8.0. Each T-number has an intensity assigned to it, with larger T-numbers indicating

2415-448: A luxury resort estimated to cost $ 450 – US$ 500 million. The developers pay less than one penny per square foot of land per month. The development will include a casino , timeshares and a cultural centre. The company is expecting to receive the casino licence for Savaiʻi island in a new law legalising casinos proposed by the government, the Casino and Gambling Bill 2010 tabled to parliament by

2576-426: A much smaller area. This replenishing of moisture-bearing air after rain may cause multi-hour or multi-day extremely heavy rain up to 40 km (25 mi) from the coastline, far beyond the amount of water that the local atmosphere holds at any one time. This in turn can lead to river flooding , overland flooding, and a general overwhelming of local water control structures across a large area. A tropical cyclone

2737-577: A number of different households situated close to each other. Like the rest of Samoa, Savaiʻi is made up of villages with most of the land collectively owned by families or ʻaiga . Most people on Savaiʻi, 93% of the island population, live on customary land . The heads of the family are called matai , the holders of family names and titles. An extended family can have a number of chiefs with different chief titles. Men and women in Samoa have equal rights to chief titles which are bestowed by consensus of

2898-493: A number of techniques considered to try to artificially modify tropical cyclones. These techniques have included using nuclear weapons , cooling the ocean with icebergs, blowing the storm away from land with giant fans, and seeding selected storms with dry ice or silver iodide . These techniques, however, fail to appreciate the duration, intensity, power or size of tropical cyclones. A variety of methods or techniques, including surface, satellite, and aerial, are used to assess

3059-519: A partnership between the local matai and villages, government, conservation organisations and international funding such as the United Nations Development Programme (UNDP). These support community based projects in villages, many of which are developed with international support and micro financing in areas of sustainable livelihoods, land management and conservation on both land and in coastal marine areas. There are wetlands in

3220-453: A pool in Safune was converted into a film processing laboratory and two young men from the village were trained to work there. Flaherty cast people from Safune in the film including local boy Taʻavale who played the lead role of 'Moana'. Another boy called Peʻa played the role of Moana's younger brother. Peʻa later became a chief with the title Taulealeausumai from the village of Faletagaloa. Playing

3381-422: A process known as rapid intensification, a period in which the maximum sustained winds of a tropical cyclone increase by 30  kn (56 km/h; 35 mph) or more within 24 hours. Similarly, rapid deepening in tropical cyclones is defined as a minimum sea surface pressure decrease of 1.75 hPa (0.052 inHg) per hour or 42 hPa (1.2 inHg) within a 24-hour period; explosive deepening occurs when

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3542-429: A remnant low-pressure area . Remnant systems may persist for several days before losing their identity. This dissipation mechanism is most common in the eastern North Pacific. Weakening or dissipation can also occur if a storm experiences vertical wind shear which causes the convection and heat engine to move away from the center. This normally ceases the development of a tropical cyclone. In addition, its interaction with

3703-411: A seawall. The President of United States declared the event as a "major disaster", for which federal assistance was provided. The severity of Cyclone Val was aptly described by a local resident who stated: "But this Cyclone was stronger than me. For the first time I felt defeated I had never felt that before. I felt it was personal between me and Cyclone. I got depressed afterward." Aid was provided to

3864-532: A second time. During December 9, Val completed its loop and started to move eastwards and gradually weaken, before it passed over the American Samoan island of Tutuila early the next day. After passing over American Samoa, Val appeared to threaten the Southern Cook Islands and was expected to pass close to Palmerston Island . However, as the system continued to weaken, it started to move more towards

4025-562: A storm. Tropical cyclone scales , such as the Saffir-Simpson hurricane wind scale and Australia's scale (Bureau of Meteorology), only use wind speed for determining the category of a storm. The most intense storm on record is Typhoon Tip in the northwestern Pacific Ocean in 1979, which reached a minimum pressure of 870  hPa (26  inHg ) and maximum sustained wind speeds of 165 kn (85 m/s; 305 km/h; 190 mph). The highest maximum sustained wind speed ever recorded

4186-487: A strong extratropical depression. Storm force winds subsequently persisted around the centre of Val's extratropical remnants for the next 3 days, before the system was captured and sheared apart by strong environmental westerlies associated with the Antarctic Circumpolar Current as it approached 50°S. Severe Tropical Cyclone Val caused over US$ 300 million in damage and caused 17 deaths, as it impacted

4347-565: A stronger system. Tropical cyclones are assessed by forecasters according to an array of patterns, including curved banding features , shear, central dense overcast, and eye, to determine the T-number and thus assess the intensity of the storm. The Cooperative Institute for Meteorological Satellite Studies works to develop and improve automated satellite methods, such as the Advanced Dvorak Technique (ADT) and SATCON. The ADT, used by

4508-405: A system has dissipated or lost its tropical characteristics, its remnants could regenerate a tropical cyclone if environmental conditions become favorable. A tropical cyclone can dissipate when it moves over waters significantly cooler than 26.5 °C (79.7 °F). This will deprive the storm of such tropical characteristics as a warm core with thunderstorms near the center, so that it becomes

4669-518: A tropical cyclone are a result of the conservation of angular momentum imparted by the Earth's rotation as air flows inwards toward the axis of rotation. As a result, cyclones rarely form within 5° of the equator . Tropical cyclones are very rare in the South Atlantic (although occasional examples do occur ) due to consistently strong wind shear and a weak Intertropical Convergence Zone . In contrast,

4830-461: A tropical cyclone's core has a negative effect on its development and intensity by diminishing atmospheric convection and introducing asymmetries in the storm's structure. Symmetric, strong outflow leads to a faster rate of intensification than observed in other systems by mitigating local wind shear. Weakening outflow is associated with the weakening of rainbands within a tropical cyclone. Tropical cyclones may still intensify, even rapidly, in

4991-401: A tropical cyclone's intensity or the direction it is traveling. Wind-pressure relationships (WPRs) are used as a way to determine the pressure of a storm based on its wind speed. Several different methods and equations have been proposed to calculate WPRs. Tropical cyclones agencies each use their own, fixed WPR, which can result in inaccuracies between agencies that are issuing estimates on

Cyclone Val - Misplaced Pages Continue

5152-616: A two-digit number and suffix letter by the warning centers that monitor them. Savaii Savaiʻi is the largest and highest island both in Samoa and in the Samoan Islands chain. The island is also the sixth largest in Polynesia , behind the three main islands of New Zealand and the Hawaiian Islands of Hawaii and Maui . While it is larger than the second main island, Upolu, it

5313-813: A typhoon. This happened in 2014 for Hurricane Genevieve , which became Typhoon Genevieve. Within the Southern Hemisphere, it is either called a hurricane, tropical cyclone or a severe tropical cyclone, depending on if it is located within the South Atlantic, South-West Indian Ocean, Australian region or the South Pacific Ocean. The descriptors for tropical cyclones with wind speeds below 65 kn (120 km/h; 75 mph) vary by tropical cyclone basin and may be further subdivided into categories such as "tropical storm", "cyclonic storm", "tropical depression", or "deep depression". The practice of using given names to identify tropical cyclones dates back to

5474-489: A volcanic crater about one thousand feet above the sea and some seven miles (11 km) inland. One 10 November 1839, the Wilkes Expedition weighed anchor at Apia and sailed westward, and on 11 November, had lost sight of Savaiʻi. With the country's independence in 1962, Samoa incorporates both traditional political structures alongside a western parliamentary system. The modern national Government of Samoa, based in

5635-564: Is a church in every village, mostly Christian denominations. Sunday is sacred and a day of rest as 98% of Samoans identify themselves as religious. White Sunday is one of the most important days of the year in Samoa when children are treated with special attention by their families and community. During World War II , Savaiʻi came under the Allies 'Samoa Defense Group' which included Upolu, Tutuila and Wallis Island and later extended in 1944 to cover bases in other islands such as Bora Bora and

5796-473: Is a rapidly rotating storm system with a low-pressure center, a closed low-level atmospheric circulation , strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls . Depending on its location and strength, a tropical cyclone is called a hurricane ( / ˈ h ʌr ɪ k ən , - k eɪ n / ), typhoon ( / t aɪ ˈ f uː n / ), tropical storm , cyclonic storm , tropical depression , or simply cyclone . A hurricane

5957-683: Is a strong tropical cyclone that occurs in the Atlantic Ocean or northeastern Pacific Ocean . A typhoon occurs in the northwestern Pacific Ocean. In the Indian Ocean and South Pacific, comparable storms are referred to as "tropical cyclones". In modern times, on average around 80 to 90 named tropical cyclones form each year around the world, over half of which develop hurricane-force winds of 65  kn (120 km/h; 75 mph) or more. Tropical cyclones typically form over large bodies of relatively warm water. They derive their energy through

6118-571: Is also the site of the entry into Pulotu , the spirit world. Nafanua's father Saveasiʻuleo was the god of Pulotu. Another well-known legend tells of two sisters, Tilafaiga and Taema , bringing the art of tattooing to Samoa from Fiti . Tilafaiga is the mother of Nafanua. The freshwater pool Mata o le Alelo 'Eyes of the Demon' from the Polynesian legend Sina and the Eel is situated in the village of Matavai on

6279-415: Is assumed at this stage that a tropical cyclone has become self-sustaining and can continue to intensify without any help from its environment. Depending on its location and strength, a tropical cyclone is referred to by different names , including hurricane , typhoon , tropical storm , cyclonic storm , tropical depression , or simply cyclone . A hurricane is a strong tropical cyclone that occurs in

6440-406: Is calculated as: where p {\textstyle p} is the density of air, u {\textstyle u} is a sustained surface wind speed value, and d v {\textstyle d_{v}} is the volume element . Around the world, tropical cyclones are classified in different ways, based on the location ( tropical cyclone basins ), the structure of

6601-545: Is currently no consensus on how climate change will affect the overall frequency of tropical cyclones. A majority of climate models show a decreased frequency in future projections. For instance, a 2020 paper comparing nine high-resolution climate models found robust decreases in frequency in the Southern Indian Ocean and the Southern Hemisphere more generally, while finding mixed signals for Northern Hemisphere tropical cyclones. Observations have shown little change in

Cyclone Val - Misplaced Pages Continue

6762-414: Is cut off from its supply of warm moist maritime air and starts to draw in dry continental air. This, combined with the increased friction over land areas, leads to the weakening and dissipation of the tropical cyclone. Over a mountainous terrain, a system can quickly weaken. Over flat areas, it may endure for two to three days before circulation breaks down and dissipates. Over the years, there have been

6923-457: Is dominated by a 15 to 20 m high canopy of Dysoxylum huntii , Omalanthus acuminatus , Reynoldsia pleiosperma and Pterophylla samoensis . Other common trees include Coprosma savaiiense , Psychotria xanthochlora , Spiraeanthemum samoense and Streblus anthropophagorum . There are nearly 500 species of flowering plants and about 200 species of ferns in Samoa, making it richer than that of any tropical Polynesian island other than those in

7084-471: Is located. A regular passenger and vehicle ferry operates seven days a week in the Apolima Strait between Salelologa and Mulifanua wharf on Upolu. The ferry crossing takes about 90-minutes with views of Apolima and Manono islands to the south. The ferries operate only during the day. Local buses and taxis are available at the terminal and township. There's also a wharf at Asau at the north west end of

7245-416: Is mainly subsistence with locals reliant on the land and the ocean for survival. Dolphins, whales and porpoises migrate through Samoa's waters. The Palolo reef worm ( Eunice viridis ) is a Samoan cuisine delicacy which appear in the ocean only one day of the year. Palolo has cultural significance and entire villages flock to the sea for harvest. Surrounded by a variety of tropical fauna, Samoan mythology

7406-534: Is mountainous, fertile and surrounded by coral reefs. Lonely Planet describes the Savaiʻi landscape as 'spectacular tropical terrain'. The island has a gently sloping profile, reaching a maximum altitude of 1,858 metres at Mt Silisili , the highest peak in the country and the Samoa Islands chain. Volcanic craters in the highlands are strung across the central ridges from Tuasivi (literally, backbone ) village in

7567-423: Is rich with stories of animals incorporated into their culture, traditional beliefs and way of life. The island is rich in biodiversity and endemic native species which are also highly threatened. The Central Savaiʻi Rainforest comprising 72,699 hectares is the largest continuous patch of rainforest in Polynesia and contains most of Samoa 's native species. Seventy percent of Samoa's settlements are by

7728-403: Is significantly less populated. Samoans sometimes refer to the island of Savaiʻi as Salafai : This is its classical Samoan name, and is used in formal oratory and prose . The island is home to 43,958 people (2016 census), and they make up 24% of the population of Samoa. The island's only township and ferry terminal is called Salelologa . It is the main point of entry to the island, and

7889-524: Is situated at the east end of Savaiʻi. A tar sealed road serves as the single main highway , connecting most of the villages. Local bus routes also operate, reaching most settlements. Savaiʻi is made up of six itūmālō ( political districts ). Each district is made up of villages that have strong traditional ties with each other — of kinship , history , and land — and that use similar matai (titles for their village chiefs). Savaiʻi's relatively limited ecotourism operations are organized mostly at

8050-601: Is the Malietoa Tanumafili II Hospital, situated in Tuasivi village. Another district hospital is in Safotu , on the central north coast. With most of the land in Samoa under customary ownership with local governance by matai , tourism experiences take place on village land and within local culture. There are hotels, but like the rest of Samoa, many villages provide beach fale accommodation for visitors all around

8211-402: Is the first country in the 21st century to switch to driving on the left. Maota Airport is a small airstrip with basic facilities situated 10-minutes south of Salelologa ferry terminal and township. Flights operate between Maota and Asau airstrip and Faleolo International Airport on Upolu. The inter-island flights take about 30-minutes. Asau Airport is an airstrip at the north west end of

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8372-445: Is the generic term for a warm-cored, non-frontal synoptic-scale low-pressure system over tropical or subtropical waters around the world. The systems generally have a well-defined center which is surrounded by deep atmospheric convection and a closed wind circulation at the surface. A tropical cyclone is generally deemed to have formed once mean surface winds in excess of 35 kn (65 km/h; 40 mph) are observed. It

8533-502: Is the greatest. However, each particular basin has its own seasonal patterns. On a worldwide scale, May is the least active month, while September is the most active month. November is the only month in which all the tropical cyclone basins are in season. In the Northern Atlantic Ocean , a distinct cyclone season occurs from June 1 to November 30, sharply peaking from late August through September. The statistical peak of

8694-535: Is the largest contiguous rainforest in Polynesia. It is dotted with more than 100 volcanic craters and contains most of Samoa 's native species of flora and fauna , making it one of the world's most globally significant conservation areas. Faʻa Sāmoa , the unique traditional culture and way of life in Samoan society, remains strong in Savaiʻi, where there are fewer signs of modern life and less development than on

8855-405: Is the storm's wind speed and r {\textstyle r} is the radius of hurricane-force winds. The Hurricane Severity Index is a scale that can assign up to 50 points to a system; up to 25 points come from intensity, while the other 25 come from the size of the storm's wind field. The IKE model measures the destructive capability of a tropical cyclone via winds, waves, and surge. It

9016-608: The African easterly jet and areas of atmospheric instability give rise to cyclones in the Atlantic Ocean and Caribbean Sea . Heat energy from the ocean acts as the accelerator for tropical cyclones. This causes inland regions to suffer far less damage from cyclones than coastal regions, although the impacts of flooding are felt across the board. Coastal damage may be caused by strong winds and rain, high waves (due to winds), storm surges (due to wind and severe pressure changes), and

9177-507: The Atlantic Ocean or northeastern Pacific Ocean , and a typhoon occurs in the northwestern Pacific Ocean. In the Indian Ocean and South Pacific, comparable storms are referred to as "tropical cyclones", and such storms in the Indian Ocean can also be called "severe cyclonic storms". Tropical refers to the geographical origin of these systems, which form almost exclusively over tropical seas. Cyclone refers to their winds moving in

9338-471: The Cook Islands , American Samoa , Samoa , Tokelau , Tonga , Tuvalu as well as Wallis and Futuna . Some of these island nations were still recovering from the effects of Severe Tropical Cyclone Ofa , which had impacted Polynesia less than two years earlier. Val's main impacts were to the Samoan Islands , where it was responsible for 14 deaths and was considered to be the worst tropical cyclone to impact

9499-464: The Cook Islands . A military governor of the Samoa Defense Group was Brigadier General Henry L. Larsen who had secret orders mandating a defensive position of the islands from east to west. The code name for the entire group of islands was "Straw" and the code name for Savaiʻi was "Strawman". The code for Upolu was "Strawhat", Tutuila "Strawstack" while Wallis Island was "Strawboard". A small base

9660-618: The Hurricane Surge Index , the Hurricane Severity Index , the Power Dissipation Index (PDI), and integrated kinetic energy (IKE). ACE is a metric of the total energy a system has exerted over its lifespan. ACE is calculated by summing the squares of a cyclone's sustained wind speed, every six hours as long as the system is at or above tropical storm intensity and either tropical or subtropical. The calculation of

9821-559: The Madden–Julian oscillation . The IPCC Sixth Assessment Report summarize the latest scientific findings about the impact of climate change on tropical cyclones. According to the report, we have now better understanding about the impact of climate change on tropical storm than before. Major tropical storms likely became more frequent in the last 40 years. We can say with high confidence that climate change increase rainfall during tropical cyclones. We can say with high confidence that

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9982-689: The Malo on Savaiʻi are situated in the village of Tuasivi , 10 minutes north of the ferry terminal and market at Salelologa . There's a district hospital, police station, post office and court houses in Tuasivi. Vaʻai Kolone , a matai and businessman from Vaisala , at the west end of the island, became the Prime Minister of Samoa twice in the 1980s. Samoa has 11 political districts (itūmālō) and 6 are in Savaiʻi; Faʻasaleleaga , Gagaʻemauga , Gagaʻifomauga , Palauli , Satupaʻitea and Vaisigano . Savaiʻi

10143-573: The Pulemelei Mound in Palauli district. Archaeology in Samoa has uncovered many pre-historic settlements including sites at Vailoa and Sapapaliʻi . Rich in Polynesian history and oral tradition, Savaiʻi is mentioned in myths and legends across the Pacific Islands and has been called the "Cradle of Polynesia." Samoan mythology tells stories of different gods. There were gods of the forest,

10304-460: The Saffir–Simpson scale . Climate oscillations such as El Niño–Southern Oscillation (ENSO) and the Madden–Julian oscillation modulate the timing and frequency of tropical cyclone development. Rossby waves can aid in the formation of a new tropical cyclone by disseminating the energy of an existing, mature storm. Kelvin waves can contribute to tropical cyclone formation by regulating

10465-561: The Saffir–Simpson scale . The trend was most clear in the North Atlantic and in the Southern Indian Ocean. In the North Pacific, tropical cyclones have been moving poleward into colder waters and there was no increase in intensity over this period. With 2 °C (3.6 °F) warming, a greater percentage (+13%) of tropical cyclones are expected to reach Category 4 and 5 strength. A 2019 study indicates that climate change has been driving

10626-501: The Samoan Islands . Early on December 7, the FMS reported that the system had become a category 3 severe tropical cyclone , as it started to be steered southwards by upper-level northerlies. Later that day, the FMS reported that Val had reached its peak 10-minute sustained wind speeds of about 165 km/h (105 mph), which made it a category 4 severe tropical cyclone on the Australian scale. The system subsequently made landfall on

10787-450: The Samoan white-eye ( Zosterops samoensis ) which is only found in the high cloud forests and alpine scrub around Mt Silisili , and Samoan moorhen ( Gallinula pacifica ), which was last recorded in 1873 near Aopo with possible sightings in 1984 and 2003. The tooth-billed pigeon , ( Didunculus strigirostris ), also known as the manumea is also endemic and now increasingly rare, leading to

10948-514: The troposphere , enough Coriolis force to develop a low-pressure center , and a pre-existing low-level focus or disturbance. There is a limit on tropical cyclone intensity which is strongly related to the water temperatures along its path. and upper-level divergence. An average of 86 tropical cyclones of tropical storm intensity form annually worldwide. Of those, 47 reach strength higher than 119 km/h (74 mph), and 20 become intense tropical cyclones, of at least Category 3 intensity on

11109-621: The Atlantic hurricane season is September 10. The Northeast Pacific Ocean has a broader period of activity, but in a similar time frame to the Atlantic. The Northwest Pacific sees tropical cyclones year-round, with a minimum in February and March and a peak in early September. In the North Indian basin, storms are most common from April to December, with peaks in May and November. In the Southern Hemisphere,

11270-467: The Equator generally have their origins in the Intertropical Convergence Zone , where winds blow from either the northeast or southeast. Within this broad area of low-pressure, air is heated over the warm tropical ocean and rises in discrete parcels, which causes thundery showers to form. These showers dissipate quite quickly; however, they can group together into large clusters of thunderstorms. This creates

11431-549: The FMS classified the system as a tropical depression by the FMS, while it was located just to the southeast of Tuvalu and moving north-westwards. The system was then named Val by the FMS during the next day, after it had become a category 1 tropical cyclone on the Australian tropical cyclone intensity scale . During that day the United States Naval Western Oceanography Center (NWOC) designated

11592-515: The Government of Samoa. The lease is unprecedented in Samoa where 80% of the land is under customary ownership, 6% freehold and the rest owned by the government. Moana (1926), one of the earliest documentaries made in the world, was filmed in Safune on the central north coast. The film was directed by Robert J. Flaherty who lived with his wife and children in Safune for more than a year. A cave with

11753-496: The Hawaiian archipelago. About 25% of the species are endemic to Samoa. The variety of tropical plant life is also a material source for floral adornment, tapa cloth , ʻie toga , perfumes, coconut oil as well as herbs and plants for traditional medicines. Common plants with everyday usage include the smooth reddish purple leaves of the ti ( Dracaena terminalis ) plant used with coconut oil for traditional massage, fofo , and

11914-473: The Japanese will and there may not be a great deal of time left. —8 February 1943 Report on Western Samoa defence by 2nd Marine Brigade's intelligence officer, Lieutenant Colonel William L. Bales. On 18 May 1942 the 3rd Marine Brigade with 4,853 officers and men were on Upolu and Savaiʻi under the command of Brigadier General Charles D. Barrett. In October 1839, Savaiʻi and the Samoa Islands were surveyed by

12075-629: The PDI is similar in nature to ACE, with the major difference being that wind speeds are cubed rather than squared. The Hurricane Surge Index is a metric of the potential damage a storm may inflict via storm surge. It is calculated by squaring the dividend of the storm's wind speed and a climatological value (33 m/s or 74 mph), and then multiplying that quantity by the dividend of the radius of hurricane-force winds and its climatological value (96.6 km or 60.0 mi). This can be represented in equation form as: where v {\textstyle v}

12236-533: The Samoan island of Savaii at around 1800 UTC (07:00 SST), while the NWOC reported that the cyclone had peaked with 1-minute sustained wind speeds of about 230 km/h (145 mph), which made it equivalent to a category 4 hurricane on the SSHWS. After Val had passed over the island, weakening upper-level winds caused the system to slow down before it made a sharp clockwise loop which almost brought it over Savaii for

12397-489: The Samoan island of Savaii. After Val had passed over Savaii and performed a clockwise loop, the FMS realised that the system would move eastwards and pass over American Samoa, which caused them to reissue the hurricane warning. As Val's precursor tropical depression developed, strong winds associated with the intertropical convergence zone, caused some minor damage to the Tuvaluan atoll of Funafuti and various other atolls in

12558-460: The South Atlantic is not a major basin, and not an official basin according to the WMO. Each year on average, around 80 to 90 named tropical cyclones form around the world, of which over half develop hurricane-force winds of 65 kn (120 km/h; 75 mph) or more. Worldwide, tropical cyclone activity peaks in late summer, when the difference between temperatures aloft and sea surface temperatures

12719-585: The United States National Hurricane Center and Fiji Meteorological Service issue alerts, watches and warnings for various island nations in their areas of responsibility. The United States Joint Typhoon Warning Center and Fleet Weather Center also publicly issue warnings about tropical cyclones on behalf of the United States Government . The Brazilian Navy Hydrographic Center names South Atlantic tropical cyclones , however

12880-575: The Western Pacific. Tropical cyclones have to have a significant amount of gale-force winds occurring around the center before they are named within the Southern Hemisphere . The names of significant tropical cyclones in the North Atlantic Ocean, Pacific Ocean, and Australian region are retired from the naming lists and replaced with another name. Tropical cyclones that develop around the world are assigned an identification code consisting of

13041-482: The affected population and helped with the reconstruction and recovery of infrastructure facilities. Samoans in the United States, Australia, and New Zealand helped finance the recovery by way of remittances to their relatives who suffered on the island. In 1991, American Samoa purchased a $ 45 million "all risk" insurance policy from the firm Affiliated FM Insurance . The firm would only pay up to $ 6.1 million for

13202-605: The affected zones based on a categorization as Category A, B, C, D, E and F. The categories are defined by the degree of damage suffered. Assistance covered individuals, households, and the State and local governments. The assistance encouraged private, nonprofit organizations (NGOs) to meet and discuss expense-related emergency work and the repair or replacement of disaster-damaged infrastructure. Assistance provided "Hazard Mitigation Grants" to secure life and property from hazards. New Zealand and Australia provided considerable assistance to

13363-404: The amount was doubled to $ 57.8 million to include punitive damages. The total damages awarded by the judgment was $ 86.7 million, which the judge stated to be "the largest insurance bad faith verdict in the state of California in 1995". The revenues of American Samoa for the fiscal years 2002 and 2003, which had been showing a downward trend, registered a substantial increase attributed to

13524-404: The blue moon butterfly species ( Hypolimnas bolina ) on Savaiʻi found that males accounted for just 1% of the population and had almost been wiped out by an invasive species. Sampling a year later showed a dramatic comeback and recovery to 40%. The surrounding Pacific Ocean , coral reefs and lagoons are rich in marine life and some are harvested as an important source of food in an economy that

13685-474: The brig surveyed the island's coastline and tides. Dr Pickering and the lieutenant were hosted by the resident missionary at Sapapaliʻi, the Reverend Mr. Hardie. The Porpoise examined the bay of Palauli where there was a missionary station under the supervision of a Mr M'Donald. Wilkes' report also described Saleaula village, Asau at the west end of the island and 'the beautiful village of Falealupo ' which

13846-522: The capital Apia with the roles of Prime Minister, Members of Parliament and western styled political structure, is referred to as the Malo . Only Samoans with chief matai titles are eligible to become Members of Parliament. Alongside Samoa's national and modern political structure is traditional authority vested in family chiefs (matai). The term Pule is applied to traditional authority in Savaiʻi. The word Pule refers to appointments or authorities conferred on certain clans or individuals, sometime in

14007-425: The capital Apia , which can also help to settle disputes. At the village level, much of the country's civil and criminal matters can be dealt with directly by the matai chief village councils. The village of Falealupo on the westernmost point of Savaiʻi, is just 20 miles (32 km) from the dateline. It was arguably the last place in the world to see the sunset until a time zone change at end of 2011. Falealupo

14168-507: The coast with increasing threat from climate change and sea level rising. As most of the land in Samoa is under customary ownership, conservation projects are developed with the approval and cooperation of villages. The Government of Samoa supports conservation covenants for three natural areas on Savaiʻi, the Falealupo Rainforest Preserve, Tafua Rainforest Preserve and Aopo Cloud Forest Reserve. The conservation projects are

14329-417: The current proposition to upgrade it to critically endangered. It is the national bird of Samoa and is found on some of the local currency. It is likely that the extensive loss of lowland forest, hunting and invasive species are responsible for the decline of this stunning species. Samoa has more native species of ferns and butterflies than New Zealand , a country 85 times larger. In 2006, research samples of

14490-514: The damages, arguing that the insurance did not cover water damage, only that caused by the wind. Attorney William Shernoff investigated and discovered that the insurance company had altered American Samoa's insurance policy to exclude damages caused by "wind-driven water", despite the fact that it still covered cyclones. The case was taken to court, and in 1995, the jury awarded the American Samoa Government $ 28.9 million. Soon after,

14651-435: The development of the westerlies . Cyclone formation is usually reduced 3 days prior to the wave's crest and increased during the 3 days after. The majority of tropical cyclones each year form in one of seven tropical cyclone basins, which are monitored by a variety of meteorological services and warning centers. Ten of these warning centers worldwide are designated as either a Regional Specialized Meteorological Centre or

14812-497: The dried root stems of Piper methysticum (Latin "pepper" and Latinized Greek "intoxicating") are mixed with water for the important ʻava ceremony conducted during cultural events and gatherings. Animal species include fruit bats such as the Samoa flying-fox ( Pteropus samoensis ), land and seabirds, skinks and geckos. The birdlife of Samoa includes a total of 82 species, of which 11 are endemic , found only in Samoa. Endemic birdlife found only on Savaiʻi include species such as

14973-422: The east towards Cape Mulinuʻu to the west. The lava fields at Saleaula village on the central north coast are the result of volcanic eruptions from Mt Matavanu (1905–1911). Most of the coastline are palm fringed beaches and there are rainforests, waterfalls, caves, freshwater pools, blowholes and coral reefs. There are also numerous archaeological sites, including star mounds, fortifications and pyramids such as

15134-486: The equator, then move poleward past the ridge axis before recurving into the main belt of the Westerlies . When the subtropical ridge position shifts due to El Niño, so will the preferred tropical cyclone tracks. Areas west of Japan and Korea tend to experience much fewer September–November tropical cyclone impacts during El Niño and neutral years. During La Niña years, the formation of tropical cyclones, along with

15295-469: The evaporation of water from the ocean surface, which ultimately condenses into clouds and rain when moist air rises and cools to saturation . This energy source differs from that of mid-latitude cyclonic storms , such as nor'easters and European windstorms , which are powered primarily by horizontal temperature contrasts . Tropical cyclones are typically between 100 and 2,000 km (62 and 1,243 mi) in diameter. The strong rotating winds of

15456-418: The evening meal and lasts about half an hour. It is usually signalled by the sound of a conch shell or the ringing of the church bell. The sa usually means no loud noise or walking through the village commons. Matai sometimes stand by the side of the main road, which pass through village land, to slow down traffic until prayers are over. Tourism is overseen by the government Samoa Visitors' Bureau, situated in

15617-530: The extended family. Traditionally, male and female roles are defined by labours and tasks, chiefly status and age. Women play an important role contributing to family decisions as well as village governance. Elders are revered and respected. Social relationships are dictated by cultural etiquettes of politeness and common greetings. The Samoan language has a 'polite' and formal variant used in Samoan oratory and ceremony as well as in communication with elders, guests, people of rank and strangers. In all villages,

15778-481: The eyewall of the storm, and an upper-level anticyclone helps channel this air away from the cyclone efficiently. However, some cyclones such as Hurricane Epsilon have rapidly intensified despite relatively unfavorable conditions. There are a number of ways a tropical cyclone can weaken, dissipate, or lose its tropical characteristics. These include making landfall, moving over cooler water, encountering dry air, or interacting with other weather systems; however, once

15939-410: The famous United States Exploring Expedition led by Charles Wilkes . The survey of Savaiʻi was performed by Lieutenant-Commandant Ringgold aboard the U.S. Brig Porpoise. Wilkes and other ships in the expedition were surveying Upolu and Tutuila at the same time. The Porpoise first touched down at the village of Sapapaliʻi . Some of the team, Dr Pickering and Lieutenant Maury were dropped off while

16100-410: The form of cold water from falling raindrops (this is because the atmosphere is cooler at higher altitudes). Cloud cover may also play a role in cooling the ocean, by shielding the ocean surface from direct sunlight before and slightly after the storm passage. All these effects can combine to produce a dramatic drop in sea surface temperature over a large area in just a few days. Conversely, the mixing of

16261-453: The frequency of very intense storms and a poleward extension of where the cyclones reach maximum intensity are among the possible consequences of human-induced climate change. Tropical cyclones use warm, moist air as their fuel. As climate change is warming ocean temperatures , there is potentially more of this fuel available. Between 1979 and 2017, there was a global increase in the proportion of tropical cyclones of Category 3 and higher on

16422-532: The general public regarding forecasts, watches, and warnings. Since the systems can last a week or longer, and more than one can be occurring in the same basin at the same time, the names are thought to reduce the confusion about what storm is being described. Names are assigned in order from predetermined lists with one, three, or ten-minute sustained wind speeds of more than 65 km/h (40 mph) depending on which basin it originates. Standards vary from basin to basin. Some tropical depressions are named in

16583-484: The insurance settlement of claims made to cover the damages caused by Cyclone Val. This resulted in fiscal surpluses. The deficit of US$ 23.1 million at the start of 2001 changed to a surplus of US$ 43.2 million by end of 2003. As the system impacted the Samoan Islands, the New Zealand Government set up an emergency task force, to coordinate their response to the cyclone. The task force planned to deploy

16744-451: The intensity from leveling off before an eye emerges in infrared imagery. The SATCON weights estimates from various satellite-based systems and microwave sounders , accounting for the strengths and flaws in each individual estimate, to produce a consensus estimate of a tropical cyclone's intensity which can be more reliable than the Dvorak technique at times. Multiple intensity metrics are used, including accumulated cyclone energy (ACE),

16905-522: The intensity of a tropical cyclone. Reconnaissance aircraft fly around and through tropical cyclones, outfitted with specialized instruments, to collect information that can be used to ascertain the winds and pressure of a system. Tropical cyclones possess winds of different speeds at different heights. Winds recorded at flight level can be converted to find the wind speeds at the surface. Surface observations, such as ship reports, land stations, mesonets , coastal stations, and buoys, can provide information on

17066-544: The island nation. During December 4, a strong wind warning was issued for the island nation of Tokelau , after the system had developed into a tropical depression. A tropical cyclone alert was subsequently issued during the next day, as it was thought that the cyclone could pose a threat to the island nation as it moved eastwards. During December 6, the FMS issued a gale warning for the whole of Tokelau, before gale-force winds of up to 75 km/h (45 mph) were observed at Atafu , as Val passed about 370 km (230 mi) to

17227-418: The island of Upolu , where the capital , Apia , is located. Samoan society is communal and based on extended family relationships and socio-cultural obligations, so that kinship and genealogies are important. These faʻa Sāmoa values are also associated with concepts of love ( alofa ), service ( tautua ) to family and community, respect ( faʻaaloalo ) and discipline ( usitaʻi ). Most families are made up of

17388-573: The island of Wallis , within the French Overseas Territory of Wallis and Futuna increased. As a result, the FMS issued gale warnings for the islands of Niuafoʻou , Niuatoputapu and Wallis, while issuing a tropical cyclone alert for the rest of the Tongan islands. However, the warnings were cancelled during the next day, as the threat of gale-force or stronger winds developing over Wallis or northern Tonga had decreased. During December 8, after

17549-467: The island such as Manase on the central north coast. These are small local businesses run by families within their villages and most of the income goes directly back to the community. There are island tours, diving, fishing, plantation trips, treks and other tourism related activities. Most shops are closed on Sundays with a few re-opening after church services in late afternoon. Every day, evening prayer ( sa ) takes place in every village around dusk before

17710-671: The island which mainly services chartered flights. A local market (open Monday – Saturday) at Salelologa sells fresh produce of fruit, vegetables and local crafts. There are also clothing stores, several small supermarkets, a wholesaler, petrol stations, bakeries, budget hotels and accommodation, buses, taxis, rental car companies as well as public amenities such as internet access, banks and Western Union money transfer outlets. There are small local shops in every village around Savaiʻi, selling basic groceries. Markets and most shops in Samoa close on Sundays with smaller outlets opening late afternoon after church services. The main hospital on Savaiʻi

17871-433: The island, sometimes used for yachting. Savaiʻi has an excellent tar-seal road circling the island. A leisurely drive around the island takes under 3 hours. The scenic drive is mostly along the coastline where most of the locals live in villages. Driving in Samoa is on the left side of the road, effective from 7 September 2009 when the government changed the law to bring motoring in line with neighbouring countries. Samoa

18032-513: The island, while winds of below gale-force were experienced on Niuafoʻou. Wallis Island also did not experience any gale-force winds, however, some minor damage was reported on the island, after some minor flooding of coastal areas occurred. During December 10, the FMS issued a gale warning for Palmerston Island and a tropical cyclone alert for the rest of the Southern Cook Islands , as Val accelerated south-eastwards and appeared to threaten

18193-512: The islands since the 1889 Apia cyclone . As a result of the impact of this storm, the name Val was retired from the tropical cyclone naming lists. On December 6, the FMS placed Western Samoa under a gale warning as it had become apparent that Val would impact the island nation, before issuing a storm and a hurricane warning for the island as the system moved closer to the archipelago. During that day, northeasterly winds and high seas caused damage to coastal areas on both Savaii and Upolu , before

18354-468: The islands. However, the system subsequently moved more towards the south-southeast than had been expected and eventually passed around 370 km (230 mi) to the west of Palmerston Island. As a result, the Southern Cook Islands were spared any major damage from the system. However, gale- and storm-force winds were reported on the island during December 11, which were subsequently attributed to

18515-404: The islands. The United Nations Development Programme subsequently funded a project between 1992 and 1995, which provided a limited reconstruction of the areas damaged by the cyclone. Total damages within the island nation were estimated at US$ 750,000. During December 6, as the system moved southeastwards towards Samoa, the threat of gale-force or stronger winds developing over northern Tonga and

18676-674: The late 1800s and early 1900s and gradually superseded the existing system—simply naming cyclones based on what they hit. The system currently used provides positive identification of severe weather systems in a brief form, that is readily understood and recognized by the public. The credit for the first usage of personal names for weather systems is generally given to the Queensland Government Meteorologist Clement Wragge who named systems between 1887 and 1907. This system of naming weather systems fell into disuse for several years after Wragge retired, until it

18837-412: The lead female role in the film was Faʻagase, a girl from Lefagaoaliʻi . The film also showed the young hero 'Moana' receiving a peʻa , a traditional Samoan tattoo. Savaiʻi island lies north west of Upolu. These two largest islands of Samoa are separated by the Apolima Strait which is about 8 miles (13 km) wide with the small inhabited islands of Manono and Apolima between them. Savaiʻi island

18998-404: The main belt of the Westerlies , by means of merging with a nearby frontal zone, can cause tropical cyclones to evolve into extratropical cyclones . This transition can take 1–3 days. Should a tropical cyclone make landfall or pass over an island, its circulation could start to break down, especially if it encounters mountainous terrain. When a system makes landfall on a large landmass, it

19159-610: The majority of people are largely sustained by plantation work and fishing with financial assistance from relatives working in Apia or overseas. Most people live in coastal villages although there are some settlements inland such as the villages of Aopo , Patamea and Sili . Behind the villages are cultivated plantations with crops of taro , cocoa koko , coconuts popo , yams palai , ʻava , fruit and vegetables as well other native plants such as pandanus for weaving ʻie tōga fine mats and bark for tapa cloth . There

19320-445: The most meaning." The tropical climate and fertile soil results in a variety of flora. Vegetation types include littoral, wetland and volcanic vegetation. Rainforests include coastal, lowland and montane forests (above 500m elevation). Cloud forests are located in the highest elevations of the island which are often under cloud cover with wet conditions. At Mt Silisili, cloud forest occurs above 1200 m elevation. The Savaiʻi forest

19481-417: The north coast in the village district of Safune . Another figure of legend is Tui Fiti , who resides at Fagamalo village in the village district of Matautu on the central north coast. The village of Falelima is associated with a dreaded spirit deity called Nifoloa. Savaiʻi is known as the "Soul of Samoa." "Here the 20th century has put down the shallowest roots, and the faʻa Samoa —the Samoan way—has

19642-522: The observed trend of rapid intensification of tropical cyclones in the Atlantic basin. Rapidly intensifying cyclones are hard to forecast and therefore pose additional risk to coastal communities. Warmer air can hold more water vapor: the theoretical maximum water vapor content is given by the Clausius–Clapeyron relation , which yields ≈7% increase in water vapor in the atmosphere per 1 °C (1.8 °F) warming. All models that were assessed in

19803-492: The opening days of December 1991, the Fiji Meteorological Service (FMS) started to monitor a small circulation, that had developed along the Intertropical Convergence Zone , just to the north of Tokelau as a result of a surge within the westerlies . Over the next few days, the system moved westwards towards Rotuma and Tuvalu , where it lay near the centre of an area of upper level outflow . During December 4,

19964-466: The overall frequency of tropical cyclones worldwide, with increased frequency in the North Atlantic and central Pacific, and significant decreases in the southern Indian Ocean and western North Pacific. There has been a poleward expansion of the latitude at which the maximum intensity of tropical cyclones occurs, which may be associated with climate change. In the North Pacific, there may also have been an eastward expansion. Between 1949 and 2016, there

20125-455: The political history of Samoa. This traditional Pule authority was centred in certain villages around Savaiʻi. In the early 20th century, these Pule areas on Savaiʻi island were Safotulafai , Saleaula , Safotu , Asau , Satupaʻitea and Palauli . Safotu, Asau, Satupaʻitea and Vailoa ( Palauli district) gained 'Pule' status at different times in the 19th Century, and together with the two older Pule districts, Safotulafai and Saleaula, became

20286-440: The potential of spawning tornadoes . Climate change affects tropical cyclones in several ways. Scientists found that climate change can exacerbate the impact of tropical cyclones by increasing their duration, occurrence, and intensity due to the warming of ocean waters and intensification of the water cycle . Tropical cyclones draw in air from a large area and concentrate the water content of that air into precipitation over

20447-413: The presence of moderate or strong wind shear depending on the evolution and structure of the storm's convection. The size of tropical cyclones plays a role in how quickly they intensify. Smaller tropical cyclones are more prone to rapid intensification than larger ones. The Fujiwhara effect , which involves interaction between two tropical cyclones, can weaken and ultimately result in the dissipation of

20608-448: The prime minister Tuilaepa Aiono Sailele Malielegaoi in March 2010. The announcement of the tourist development raised concern among environmental group O Le Siʻosiʻomaga Society about the impact of the development. The Samoa Hotel Association also expressed concern at the size of the development and its impact on the island's environment and infrastructure. The development is supported by

20769-444: The release of latent heat from the saturated soil. Orographic lift can cause a significant increase in the intensity of the convection of a tropical cyclone when its eye moves over a mountain, breaking the capped boundary layer that had been restraining it. Jet streams can both enhance and inhibit tropical cyclone intensity by influencing the storm's outflow as well as vertical wind shear. On occasion, tropical cyclones may undergo

20930-492: The same intensity. The passage of a tropical cyclone over the ocean causes the upper layers of the ocean to cool substantially, a process known as upwelling , which can negatively influence subsequent cyclone development. This cooling is primarily caused by wind-driven mixing of cold water from deeper in the ocean with the warm surface waters. This effect results in a negative feedback process that can inhibit further development or lead to weakening. Additional cooling may come in

21091-488: The same system. The ASCAT is a scatterometer used by the MetOp satellites to map the wind field vectors of tropical cyclones. The SMAP uses an L-band radiometer channel to determine the wind speeds of tropical cyclones at the ocean surface, and has been shown to be reliable at higher intensities and under heavy rainfall conditions, unlike scatterometer-based and other radiometer-based instruments. The Dvorak technique plays

21252-513: The sea can result in heat being inserted in deeper waters, with potential effects on global climate . Vertical wind shear decreases tropical cyclone predicability, with storms exhibiting wide range of responses in the presence of shear. Wind shear often negatively affects tropical cyclone intensification by displacing moisture and heat from a system's center. Low levels of vertical wind shear are most optimal for strengthening, while stronger wind shear induces weakening. Dry air entraining into

21413-401: The seas, rain, harvest, villages, and war. There were two types of gods: atua , who had non-human origins, and aitu , who were of human origin. Tagaloa was a supreme god who made the islands and the people. Mafuiʻe was the god of earthquakes . There were also a number of war gods. Nafanua , Samoa's warrior goddess, hails from the village of Falealupo at the west end of the island, which

21574-457: The six Pule centres on Savaiʻi. In 1908, the 'Mau a Pule' resistance movement to colonial rule, which grew to become the national Mau movement , began on Savaiʻi and represented traditional authority against the German administration of Samoa. The equivalent term 'Tumua' is associated with traditional authority on Upolu island. At the local level throughout Samoa, traditional authority is vested in

21735-543: The south-southeast then had been expected, which spared the Cook Islands. During December 12, the FMS reported that Val had weakened into a category two tropical cyclone and passed the primary warning responsibility for the system to the New Zealand Meteorological Service (NZMS) after Val had moved out of its area of responsibility. Shortly after moving into the NZMS's area of responsibility, Val transitioned into

21896-483: The south-west coast is owned by locals and was one of the first tourism accommodations attracting surfers. Other surfing spots around Savaiʻi include breaks off the villages of Lano , Aganoa Beach by Tafua , Lefagaoaliʻi , Lelepa and Fagamalo . In 2008, an American company South Pacific Development Group (SPDG) obtained a 120-year lease for 600 acres (2.4 km ) of prime oceanfront customary land in Sasina , to build

22057-448: The south-west of the island nation. Squally conditions subsequently persisted over the islands for the next few days, with Fakaofo recording gale-force winds during December 10, in association with a convective rainband . Within the island nation, residents took refuge in a school building, while strong winds and high seas caused damage to homes and several uncompleted seawall structures, that were being installed following Ofa's impacts on

22218-480: The southwest of Savaii, which almost brought Val over the island for a second time. After completing the cyclonic loop, Val moved eastwards and passed about 20 km (10 mi) to the south of Upolu during December 9, before it started to move south-eastwards away from the Samoan Islands during December 10, after it had made landfall on Tutuila in American Samoa. On December 6, the FMS placed American Samoa under

22379-594: The subtropical ridge position, shifts westward across the western Pacific Ocean, which increases the landfall threat to China and much greater intensity in the Philippines . The Atlantic Ocean experiences depressed activity due to increased vertical wind shear across the region during El Niño years. Tropical cyclones are further influenced by the Atlantic Meridional Mode , the Quasi-biennial oscillation and

22540-419: The surface pressure decreases by 2.5 hPa (0.074 inHg) per hour for at least 12 hours or 5 hPa (0.15 inHg) per hour for at least 6 hours. For rapid intensification to occur, several conditions must be in place. Water temperatures must be extremely high, near or above 30 °C (86 °F), and water of this temperature must be sufficiently deep such that waves do not upwell cooler waters to

22701-483: The surface. On the other hand, Tropical Cyclone Heat Potential is one of such non-conventional subsurface oceanographic parameters influencing the cyclone intensity. Wind shear must be low. When wind shear is high, the convection and circulation in the cyclone will be disrupted. Usually, an anticyclone in the upper layers of the troposphere above the storm must be present as well—for extremely low surface pressures to develop, air must be rising very rapidly in

22862-621: The system and its intensity. For example, within the Northern Atlantic and Eastern Pacific basins, a tropical cyclone with wind speeds of over 65  kn (120 km/h; 75 mph) is called a hurricane , while it is called a typhoon or a severe cyclonic storm within the Western Pacific or North Indian oceans. When a hurricane passes west across the International Dateline in the Northern Hemisphere, it becomes known as

23023-423: The system as Tropical Cyclone 06P and started to issue advisories, while Val started to move towards the south-southeast, after the upper level north-westerly steering winds increased. During December 6, the NWOC reported that the system had become equivalent to a category 2 hurricane on the Saffir-Simpson hurricane scale as Val continued to steadily intensify and moved south-eastwards, away from Tuvalu and towards

23184-509: The system continued to weaken, it started to move more towards the south-southeast than had been expected, which spared the Cook Islands. During December 13, Val became a strong extratropical depression, before the system was captured and sheared apart by strong environmental westerlies associated with the Antarctic Circumpolar Current as it approached 50°S during December 16. The cyclone lasted for five days in American Samoa and

23345-486: The system had made landfall on Savaii, Val started to move south-westwards and posed another threat to northern Tonga. As a result, a gale warning was reissued for Niuatoputapu, while the rest of Tonga was placed under a strong wind warning. A storm warning was subsequently issued for Niuatoputapu during December 9, after Val had produced gale-force winds over the island and moved closer to it. Storm-force winds of around 95 km/h (60 mph) were subsequently experienced on

23506-478: The system had made landfall, Val started to move south-westwards and away from the Western Samoa, which prompted the FMS to forecast that winds over the islands would decrease over the islands during December 9. This had the impact of causing Samoan's to drop their guard, start clearing up, repairing houses and going about their day to day business, however, during that day the system completed a cyclonic loop just to

23667-417: The system to slow down before it made a sharp clockwise loop which almost brought it over Savaii for a second time. On December 9, Val completed its loop and started to move eastwards and gradually weakened before it passed over American Samoa early the next day. After passing over American Samoa, Val appeared to threaten the Southern Cook Islands and was expected to pass close to Palmerston Island. However, as

23828-423: The tropical cyclone year begins on July 1 and runs all year-round encompassing the tropical cyclone seasons, which run from November 1 until the end of April, with peaks in mid-February to early March. Of various modes of variability in the climate system, El Niño–Southern Oscillation has the largest effect on tropical cyclone activity. Most tropical cyclones form on the side of the subtropical ridge closer to

23989-628: The village level. The Mau , Samoa's non-violent movement for political independence during colonialism in the early 1900s, had its beginnings on Savaiʻi, with the Mau a Pule movement . The island is the largest shield volcano in the South Pacific . Its most recent eruptions were in the early 1900s. Its central region comprises the Central Savaiʻi Rainforest , extending over 72,699 hectares (726.99 square kilometres; 280.69 square miles) which

24150-413: The village of Satoʻalepai on the central north coast where large sea green turtles ( Chelonia mydas ) are kept by the locals as an eco-tourism experience for visitors and provide extra income for communities. Another turtle habitat is at the village of Auala on the north west coast. Salelologa is the main port and township, situated at the east end of the island where the inter-island ferry terminal

24311-451: The weaker of two tropical cyclones by reducing the organization of the system's convection and imparting horizontal wind shear. Tropical cyclones typically weaken while situated over a landmass because conditions are often unfavorable as a result of the lack of oceanic forcing. The Brown ocean effect can allow a tropical cyclone to maintain or increase its intensity following landfall , in cases where there has been copious rainfall, through

24472-598: The weather stations at Apia and Faleolo started to report that gale force winds were occurring during December 7. In a radio broadcast ahead of Val making landfall, the then Samoan Prime Minster: Tofilau Eti Alesana prayed for the country to be spared the worst of Val, but also urged Samoan's to accept the storm as God's will. The system made landfall on the island of Savaii at about 18:00 UTC (07:00 SST) on December 7, where hurricane-force winds of up to 165 km/h (105 mph) and wind-gusts of up to 240 km/h (150 mph) were thought to have occurred. After

24633-402: The wind speed of Hurricane Helene by 11%, it increased the destruction from it by more than twice. According to World Weather Attribution the influence of climate change on the rainfall of some latest hurricanes can be described as follows: Tropical cyclone intensity is based on wind speeds and pressure. Relationships between winds and pressure are often used in determining the intensity of

24794-406: Was named Val on December 5, after it had become a category 1 tropical cyclone on the Australian tropical cyclone intensity scale . The system subsequently continued to intensify as it moved towards the Samoan Islands and peaked as a category 4 severe tropical cyclone, as it made landfall on the island of Savaii on December 6. After Val had passed over the island, weakening upper-level winds caused

24955-779: Was 185 kn (95 m/s; 345 km/h; 215 mph) in Hurricane Patricia in 2015—the most intense cyclone ever recorded in the Western Hemisphere . Warm sea surface temperatures are required for tropical cyclones to form and strengthen. The commonly-accepted minimum temperature range for this to occur is 26–27 °C (79–81 °F), however, multiple studies have proposed a lower minimum of 25.5 °C (77.9 °F). Higher sea surface temperatures result in faster intensification rates and sometimes even rapid intensification . High ocean heat content , also known as Tropical Cyclone Heat Potential , allows storms to achieve

25116-523: Was a slowdown in tropical cyclone translation speeds. It is unclear still to what extent this can be attributed to climate change: climate models do not all show this feature. A 2021 study review article concluded that the geographic range of tropical cyclones will probably expand poleward in response to climate warming of the Hadley circulation . When hurricane winds speed rise by 5%, its destructive power rise by about 50%. Therfore, as climate change increased

25277-659: Was designated by the United States Government as a major disaster on December 13, 1991. Western Samoa suffered more damage than American Samoa. The cyclone devastated the islands with 150-mile-per-hour (240 km/h) winds and 50-foot (15 m) waves. The overall damages caused by Cyclone Val in American Samoa have been variously assessed. One estimate put the damages at $ 50 million in American Samoa and $ 200 million in Western Samoa due to damage to electrical, water, and telephone connections and destruction of various government buildings, schools, and houses. During

25438-522: Was revived in the latter part of World War II for the Western Pacific. Formal naming schemes have subsequently been introduced for the North and South Atlantic, Eastern, Central, Western and Southern Pacific basins as well as the Australian region and Indian Ocean. At present, tropical cyclones are officially named by one of twelve meteorological services and retain their names throughout their lifetimes to provide ease of communication between forecasters and

25599-400: Was set up on the central north coast village of Fagamalo , which had a wharf and anchorage. Fagamalo was the main village for the colonial administration at the time on Savaiʻi, situated where the small post office is today. In its present unprotected state, Western Samoa is a hazard of first magnitude for the defense of American Samoa. The conclusion is inescapable that if we don't occupy it

25760-481: Was the site of Millennium 2000 celebrations and reported by the BBC as 'the last place on earth to enter the new millennium.' Falealupo also has protected rainforests. Savaiʻi has surfing off reef breaks all around the island, with more waves during summer on the north coast and the south coast in winter. The conditions are not for novice surfers and there can be dangerous undercurrents and rips. Satuiatua Beach Fales on

25921-543: Was under the charge of a Tongan missionary. At the 'north point' of the island, the brig found 'good anchorage' in the bay of Matautu (where the village of Fagamalo is situated). The brig was anchored and the harbour surveyed. Wilkes' wrote that this was the harbour on the island where a vessel could anchor in safety. Here, in Matautu, the explorers noticed a difference with other parts of Savaiʻi. A great difference in form, physiognomy and manners...was observed here, as well as

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