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1982–83 South-West Indian Ocean Cyclone Season
The 1982–83 South-West Indian Ocean cyclone season was the least active cyclone season in the basin since 1961–1962. There were six systems that were named, although three of them – Arilisy, Clera, and Fely – failed to intensify beyond tropical depression status. No storms reached tropical cyclone status, according to the official warning agency for the basin, Météo-France, although the two strongest storms – Bemany and Elinah – peaked just below that intensity. The first named storm, Arilisy, formed on October 27, and dissipated without having affected land. However, the Joint Typhoon Warning Center (JTWC), which is an unofficial warning center for the basin, briefly tracked a tropical depression in July. The next storm was Bemany, which passed east of Mauritius near peak intensity in early December. Tropical Depression Clera existed briefly in the middle of September, and Tropical Storm Dadafy moved across the eastern portion of the basin in late December. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2010–11 South-West Indian Ocean Cyclone Season
The 2010–11 South-West Indian Ocean cyclone season was the least active cyclone season on record in the basin, tied with 1982–83, producing only three systems of gale intensity. This was due to cooler than normal water temperatures and the Walker circulation – a broad atmospheric circulation – causing unusually moist conditions in the eastern Indian Ocean and unusually dry conditions in the western Indian Ocean. The basin includes the waters of the ocean south of the equator and west of 90º E to the eastern coast of Africa. There were nine tropical or subtropical cyclones during the season, including five weak tropical disturbances or depressions, mostly in the northeastern portion of the basin or to the east of Madagascar. The first of these systems developed on 25 October 2010, which had its origins in the northeastern portion of the basin. On 29 November, the first named storm – Abele – also formed in the same area, strengthening to become one o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subtropical Cyclone
A subtropical cyclone is a weather system that has some characteristics of both tropical cyclone, tropical and extratropical cyclones. As early as the 1950s, meteorologists were uncertain whether they should be characterized as Tropical cyclone, tropical or extratropical cyclones. They were officially recognized and titled by the National Hurricane Center in 1972. Beginning in 2002, subtropical cyclones began receiving names from the official tropical cyclone lists in the North Atlantic hurricane, North Atlantic basin. Subtropical cyclones are also recognized in the South-West Indian Ocean tropical cyclone, South-West Indian Ocean and South Atlantic tropical cyclone, South Atlantic basins. There are two definitions currently used for subtropical cyclones depending on their location. Across the north Atlantic and southwest Indian Ocean, they require some central Convectional Precipitation, convection fairly near the center surrounding a warming core existing in the mid-levels of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anticyclone
A high-pressure area, high, or anticyclone, is an area near the surface of a planet where the atmospheric pressure is greater than the pressure in the surrounding regions. Highs are middle-scale meteorological features that result from interplays between the relatively larger-scale dynamics of an entire planet's atmospheric circulation. The strongest high-pressure areas result from masses of cold air which spread out from polar regions into cool neighboring regions. These highs weaken once they extend out over warmer bodies of water. Weaker—but more frequently occurring—are high-pressure areas caused by atmospheric subsidence: Air becomes cool enough to precipitate out its water vapor, and large masses of cooler, drier air descend from above. Within high-pressure areas, winds flow from where the pressure is highest, at the center of the area, towards the periphery where the pressure is lower. However, the direction is not straight from the center outwards, but curved du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Circulation
Atmospheric circulation is the large-scale movement of Atmosphere of Earth, air and together with ocean circulation is the means by which thermal energy is redistributed on the surface of the Earth. The Earth's atmospheric circulation varies from year to year, but the large-scale structure of its circulation remains fairly constant. The smaller-scale weather systems – middle latitudes, mid-latitude low-pressure area, depressions, or tropical convective cells – occur chaotically, and long-range weather predictions of those cannot be made beyond ten days in practice, or a month in theory (see chaos theory and the butterfly effect). The Earth's weather is a consequence of its illumination by the Sun and the laws of thermodynamics. The atmospheric circulation can be viewed as a heat engine driven by the Sun's energy and whose heat sink, energy sink, ultimately, is the blackness of space. The work produced by that engine causes the motion of the masses of air, and in that process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agaléga
Agaléga () is a dependency of Mauritius, as defined by the Constitution of Mauritius, which consists of two outer islands located in the Indian Ocean, about north of Mauritius Island. Similar to other Mauritian islands such as St. Brandon, Agaléga is run directly by the Prime Minister of Mauritius through the Prime Minister's Office to the Outer Island Development Corporation (OIDC). The population of the islands rose from 289 in 2011 to 330 in 2022. The islands have a total area of . The North island is long and wide, while the South island is long and wide. The North Island is home to the islands' airstrip and the capital Vingt-Cinq. The islands are known for their production of coconuts, their main industry and, also, for the Agalega day gecko. Etymology There are three different explanations for the name Agaléga. # One hypothesis is that the Portuguese explorer, Dom Pedro Mascarenhas, named Agaléga and the island of Sainte Marie (off the east coast of Madag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convection (meteorology)
Atmospheric convection is the vertical transport of heat and moisture in the atmosphere. It occurs when warmer, less dense air rises, while cooler, denser air sinks. This process is driven by Air parcel, parcel-environment instability, meaning that a "parcel" of air is warmer and less dense than the surrounding environment at the same altitude. This difference in temperature and density (and sometimes humidity) causes the parcel to rise, a process known as buoyancy. This rising air, along with the compensating sinking air, leads to mixing, which in turn expands the height of the planetary boundary layer (PBL), the lowest part of the atmosphere directly influenced by the Earth's surface. This expansion contributes to increased Wind, winds, cumulus cloud development, and decreased surface Dew point, dew points (the temperature below which condensation occurs). Convection plays a crucial role in weather patterns, influencing cloud formation, wind, and the development of Thunderstor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seychelles
Seychelles (, ; ), officially the Republic of Seychelles (; Seychellois Creole: ), is an island country and archipelagic state consisting of 155 islands (as per the Constitution) in the Indian Ocean. Its capital and largest city, Victoria, Seychelles, Victoria, is east of mainland Africa. Nearby island countries and territories include the Comoros, Madagascar, Mauritius, and the French Fifth Republic, French overseas departments and regions of France, overseas departments of Mayotte and Réunion to the south; and the Chagos Archipelago to the east. Seychelles is the list of African countries by area, smallest country in Africa as well as the list of African countries by population, least populated sovereign African country, with an estimated population of 100,600 in 2022. Seychelles was uninhabited prior to being encountered by Europeans in the 16th century. It faced competing French and British interests until it came under full British control in the early 19th century. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convergence Zone
A convergence zone in meteorology is a region in the atmosphere where two prevailing flows meet and interact, usually resulting in distinctive weather conditions. This causes a mass accumulation that eventually leads to a vertical movement and to the formation of clouds and precipitation. Large-scale convergence, called synoptic-scale convergence, is associated with weather systems such as baroclinic troughs, low-pressure areas, and cyclones. The large-scale convergence zone formed over the equator, the Intertropical Convergence Zone, has condensed and intensified as a result of the global increase in temperature. Small-scale convergence will give phenomena from isolated cumulus clouds to large areas of thunderstorms. The inverse of convergence is divergence, such as the horse latitudes. Large scale An example of a convergence zone is the Intertropical Convergence Zone (ITCZ), a low pressure area which girdles the Earth at the Equator.Waliser, D.E.; Jiang, X. (20 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodrigues
Rodrigues ( ; Mauritian Creole, Creole: ) is a Autonomous administrative division, autonomous Outer islands of Mauritius, outer island of the Republic of Mauritius in the Indian Ocean, about east of Mauritius. It is part of the Mascarene Islands, which include Mauritius and Réunion. Like Agaléga, Rodrigues is a constituent island of the Mauritius, Republic of Mauritius, under the Constitution of Mauritius and still remains, as explicitly defined by the same Constitution, part of the Sovereignty of Mauritius, together with the following islands: "Agaléga, Tromelin Island, Tromelin, Cargados Carajos (Saint Brandon), Chagos Archipelago ... Diego Garcia and other islands included in the State of Mauritius". Rodrigues is of volcanic origin and is surrounded by coral reef, and some tiny uninhabited islands lie just off its coast. The island used to be the tenth District of Mauritius; it gained autonomous status on 12 October 2002, and is governed by the Rodrigues Regional Assemb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Air Force
The United States Air Force (USAF) is the Air force, air service branch of the United States Department of Defense. It is one of the six United States Armed Forces and one of the eight uniformed services of the United States. Tracing its origins to 1 August 1907, as a part of the United States Army Signal Corps, the USAF was established by transfer of personnel from the Army Air Forces with the enactment of the National Security Act of 1947. It is the second youngest branch of the United States Armed Forces and the fourth in United States order of precedence, order of precedence. The United States Air Force articulates its core missions as air supremacy, intelligence, surveillance, target acquisition, and reconnaissance, global integrated intelligence, surveillance and reconnaissance, airlift, rapid global mobility, Strategic bombing, global strike, and command and control. The United States Department of the Air Force, Department of the Air Force, which serves as the USAF's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Navy
The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 million tons in 2021. It has the world's largest aircraft carrier fleet, with List of aircraft carriers in service, eleven in service, one undergoing trials, two new carriers under construction, and six other carriers planned as of 2024. With 336,978 personnel on active duty and 101,583 in the Ready Reserve, the U.S. Navy is the third largest of the United States military service branches in terms of personnel. It has 299 deployable combat vessels and about 4,012 operational aircraft as of 18 July 2023. The U.S. Navy is one of six United States Armed Forces, armed forces of the United States and one of eight uniformed services of the United States. The United States Navy traces its origins to the Continental Navy, which was established during ... [...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] |
