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1996–97 South-West Indian Ocean Cyclone Season
The 1996–97 South-West Indian Ocean cyclone season was the longest on record, with both an unusually early start and unusually late ending. Most activity was from November through February. According to the Météo-France office (MFR) at Réunion, there were 21 tropical disturbances, 14 of which intensified into tropical depressions. There were 12 tropical cyclone naming, named storms, beginning with Antoinette and proceeding sequentially until Tropical Storm Lisette, Lisette. In addition, the Joint Typhoon Warning Center also warned on storms in the region, which identified five other tropical storms. Five of the storms attained Tropical cyclone scales#South-West Indian Ocean, tropical cyclone status, or with 10–minute maximum sustained winds of at least ; of these, three strengthened further into intense tropical cyclones, with Daniella and Helinda tied for strongest storm of the season. In August, a tropical depression developed in the south-west Indian Ocean for the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1994–95 South-West Indian Ocean Cyclone Season
The 1994–95 South-West Indian Ocean cyclone season was fairly active, with storms forming regularly from October through April. It was much less damaging than its predecessor, and most of the storms in the season remained over water or only brushed land. The first system was Tropical Depression A1, which formed in October and passed north of Madagascar. The first named storm was Albertine, which formed on November 23 in the northeastern portion of the basin and became one of three intense tropical cyclones. The last storm was Marlene, which was also an intense tropical cyclone and dissipated on April 11. Most of the storms originated from the Intertropical Convergence Zone. In late December into early January, tropical storms Bentha and Christelle persisted to the east of Madagascar, undergoing the Fujiwhara effect with each other. Later in January, Dorina became the second of three intense tropical cyclones, but weakened before passing near Rodrigues. Tropical Depre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dvorak Technique
The Dvorak technique (developed between 1969 and 1984 by Vernon Dvorak) is a widely used system to estimate tropical cyclone intensity (which includes tropical depression, tropical storm, and hurricane/typhoon/intense tropical cyclone intensities) based solely on visible and infrared Weather satellite, satellite images. Within the Dvorak satellite strength estimate for tropical cyclones, there are several Pattern recognition, visual patterns that a cyclone may take on which define the upper and lower bounds on its intensity. The primary patterns used are curved rainband, band pattern (T1.0-T4.5), Wind shear#Effects on tropical cyclones, shear pattern (T1.5–T3.5), central dense overcast (CDO) pattern (T2.5–T5.0), central cold cover (CCC) pattern, banding eye pattern (T4.0–T4.5), and Eye (cyclone), eye pattern (T4.5–T8.0). Both the central dense overcast and embedded eye pattern use the size of the CDO. The CDO pattern intensities start at T2.5, equivalent to minimal trop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trough (meteorology)
A trough is an elongated region of relatively low atmospheric pressure without a closed Isobar (meteorology), isobaric contour that would define it as a Low-pressure area, low pressure area. Since low pressure implies a low Geopotential height, height on a pressure surface, Valley, troughs and Ridge (meteorology), ridges refer to features in an identical sense as those on a topographic map. Troughs may be at the surface, or aloft, at altitude. Near-surface troughs sometimes mark a weather front associated with clouds, showers, and a wind direction shift. Upper-level troughs in the jet stream (as shown in diagram) reflect Cyclonic rotation, cyclonic filaments of vorticity. Their motion induces upper-level wind divergence, lifting and cooling the air ahead (downstream) of the trough and helping to produce cloudy and rain conditions there. Unlike fronts, there is not a universal symbol for a trough on a surface weather analysis chart. The weather charts in some countries or regions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bureau Of Meteorology
The Bureau of Meteorology (BOM or BoM) is an executive agency of the Government of Australia, Australian Government that is responsible for providing Weather forecasting, weather forecasts and Meteorology, meteorological services to Australia and neighbouring countries. It was established in 1906 under the Meteorology Act (Cth), and brought together the States and territories of Australia, state meteorological services that existed before then. The states officially transferred their weather recording responsibilities to the Bureau of Meteorology on 1 January 1908. History The Bureau of Meteorology was established on 1 January 1908 following the passage of the ''Meteorology Act 1906''. Prior to Federation of Australia, Federation in 1901, each colony had had its own meteorological service, with all but two colonies also having a subsection devoted to astronomy. In August 1905, federal home affairs minister Littleton Groom surveyed state governments for their willingness to cede ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sumatra
Sumatra () is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the list of islands by area, sixth-largest island in the world at 482,286.55 km2 (182,812 mi.2), including adjacent islands such as the Simeulue Island, Simeulue, Nias Island, Nias, Mentawai Islands, Mentawai, Enggano Island, Enggano, Riau Islands, Bangka Belitung and Krakatoa archipelago. Sumatra is an elongated landmass spanning a diagonal northwest–southeast axis. The Indian Ocean borders the northwest, west, and southwest coasts of Sumatra, with the island chain of Simeulue, Nias, Mentawai Islands, Mentawai, and Enggano off the western coast. In the northeast, the narrow Strait of Malacca separates the island from the Malay Peninsula, which is an extension of the Eurasian continent. In the southeast, the narrow Sunda Strait, containing the Krakatoa archipelago, separates Sumatra from Java. The northern tip of Sumatra is near ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guinea, Indonesia is the world's largest archipelagic state and the List of countries and dependencies by area, 14th-largest country by area, at . With over 280 million people, Indonesia is the world's List of countries and dependencies by population, fourth-most-populous country and the most populous Islam by country, Muslim-majority country. Java, the world's List of islands by population, most populous island, is home to more than half of the country's population. Indonesia operates as a Presidential system, presidential republic with an elected People's Consultative Assembly, legislature and consists of Provinces of Indonesia, 38 provinces, nine of which have Autonomous administrative divisi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mozambique Channel
The Mozambique Channel (, , ) is an arm of the Indian Ocean located between the Southeast African countries of Madagascar and Mozambique. The channel is about long and across at its narrowest point, and reaches a depth of about off the coast of Mozambique. A warm current, the Mozambique Current, flows in a southward direction in the channel, leading into the Agulhas Current off the east coast of Southern Africa. Extent The International Hydrographic Organization (IHO) defines the limits of the Mozambique Channel as follows: ::''On the North.'' A line from the estuary of the River Rovuma () to Ras Habu, the northernmost point of Ile Grande Comore, the northernmost of the Comore (Comoro) Islands, to Cap d'Ambre (Cape Amber), the northern extremity of Madagascar (). ::''On the East.'' The west coast of Madagascar. ::''On the South.'' A line from Cap Sainte-Marie, the southern extremity of Madagascar to Ponto do Ouro on the mainland (). ::''On the West.'' The coast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wind Shear
Wind shear (; also written windshear), sometimes referred to as wind gradient, is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical or horizontal wind shear. Vertical wind shear is a change in wind speed or direction with a change in altitude. Horizontal wind shear is a change in wind speed with a change in lateral position for a given altitude. Wind shear is a microscale meteorological phenomenon occurring over a very small distance, but it can be associated with mesoscale or synoptic scale weather features such as squall lines and cold fronts. It is commonly observed near microbursts and downbursts caused by thunderstorms, fronts, areas of locally higher low-level winds referred to as low-level jets, near mountains, radiation inversions that occur due to clear skies and calm winds, buildings, wind turbines, and sailboats. Wind shear has significant effects on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eye (cyclone)
The eye is a region of mostly calm weather at the center of a tropical cyclone. The eye of a storm is a roughly circular area, typically in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the most severe weather and highest winds of the cyclone occur. The cyclone's lowest barometric pressure occurs in the eye and can be as much as 15 percent lower than the pressure outside the storm. In strong tropical cyclones, the eye is characterized by light winds and clear skies, surrounded on all sides by a towering, symmetric eyewall. In weaker tropical cyclones, the eye is less well defined and can be covered by the central dense overcast, an area of high, thick clouds that show up brightly on satellite imagery. Weaker or disorganized storms may also feature an eyewall that does not completely encircle the eye or have an eye that features heavy rain. In all storms, however, the eye is where the barometer reading is lowest. Structure A typical tropi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Dense Overcast
The central dense overcast, or CDO, of a tropical cyclone or strong subtropical cyclone is the large central area of thunderstorms surrounding its circulation center, caused by the formation of its eyewall. It can be round, angular, oval, or irregular in shape. This feature shows up in tropical cyclones of tropical storm or hurricane strength. How far the center is embedded within the CDO, and the temperature difference between the cloud tops within the CDO and the cyclone's eye, can help determine a tropical cyclone's intensity with the Dvorak technique. Locating the center within the CDO can be a problem with strong tropical storms and minimal hurricanes as its location can be obscured by the CDO's high cloud canopy. This center location problem can be resolved through the use of microwave satellite imagery. After a cyclone strengthens to around hurricane intensity, an eye appears at the center of the CDO, defining its center of low pressure and its cyclonic wind field. Tropi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cocos Islands
The Cocos (Keeling) Islands (), officially the Territory of Cocos (Keeling) Islands (; ), are an Australian external territory in the Indian Ocean, comprising a small archipelago approximately midway between Australia and Sri Lanka and relatively close to the Indonesian island of Sumatra. The territory's dual name (official since the islands' incorporation into Australia in 1955) reflects that the islands have historically been known as either the Cocos Islands or the Keeling Islands. The territory consists of two atolls made up of 27 coral islands, of which only two – West Island and Home Island – are inhabited. The population of around 600 people consists mainly of Cocos Malays, who mostly practise Sunni Islam and speak a dialect of Malay as their first language. The territory is administered by the Australian federal government's Department of Infrastructure, Transport, Regional Development, Communications and the Arts as an Australian external territory and toge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low-pressure Area
In meteorology, a low-pressure area (LPA), low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. It is the opposite of a high-pressure area. Low-pressure areas are commonly associated with inclement weather (such as cloudy, windy, with possible rain or storms), while high-pressure areas are associated with lighter winds and clear skies. Winds circle anti-clockwise around lows in the northern hemisphere, and clockwise in the southern hemisphere, due to opposing Coriolis forces. Low-pressure systems form under areas of wind divergence that occur in the upper levels of the atmosphere (aloft). The formation process of a low-pressure area is known as cyclogenesis. In meteorology, atmospheric divergence aloft occurs in two kinds of places: * The first is in the area on the east side of upper troughs, which form half of a Rossby wave within the Westerlies (a trough with large wavelength that extends through the troposphere). * A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
