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Cyclone Enawo
Intense Tropical Cyclone Enawo was the strongest tropical cyclone of the 2016–17 South-West Indian Ocean cyclone season. Enawo was the strongest tropical cyclone to strike Madagascar since Cyclone Gafilo, Gafilo in 2004, killing 78 people and causing $400 million in damages. Forming as a moderate tropical storm on 3 March, Enawo initially drifted and intensified slowly. It strengthened into a tropical cyclone on 5 March and further an intense tropical cyclone on 6 March. Enawo made landfall over Sava Region on 7 March just after reaching peak intensity, and it emerged back into the Indian Ocean as a post-tropical cyclone, post-tropical depression late on 9 March, before dissipating two days later. The most severe impacts were seen in the districts of Antalaha and Maroantsetra. Meteorological history A monsoon trough started to persist west of Diego Garcia in late February 2017 as the Madden–Julian oscillation (MJO) over the Indian Ocean grew more noticeable. On 2 March, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Madagascar
Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa across the Mozambique Channel. At Madagascar is the world's second-largest island country, after Indonesia. The nation is home to around 30 million inhabitants and consists of the island of Madagascar (the fourth-largest island in the world), along with numerous smaller peripheral islands. Following the prehistoric breakup of the supercontinent Gondwana, Madagascar split from the Indian subcontinent around 90 million years ago, allowing native plants and animals to evolve in relative isolation. Consequently, Madagascar is a biodiversity hotspot; over 90% of its wildlife is endemic. Human settlement of Madagascar occurred during or before the mid first millennium AD by Austronesian peoples, presumably arriving on outrigger cano ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordinated Universal Time
Coordinated Universal Time or UTC is the primary time standard by which the world regulates clocks and time. It is within about one second of mean solar time (such as UT1) at 0° longitude (at the IERS Reference Meridian as the currently used prime meridian) and is not adjusted for daylight saving time. It is effectively a successor to Greenwich Mean Time (GMT). The coordination of time and frequency transmissions around the world began on 1 January 1960. UTC was first officially adopted as CCIR Recommendation 374, ''Standard-Frequency and Time-Signal Emissions'', in 1963, but the official abbreviation of UTC and the official English name of Coordinated Universal Time (along with the French equivalent) were not adopted until 1967. The system has been adjusted several times, including a brief period during which the time-coordination radio signals broadcast both UTC and "Stepped Atomic Time (SAT)" before a new UTC was adopted in 1970 and implemented in 1972. This change also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Post-tropical Cyclone
A post-tropical cyclone is a former tropical cyclone that no longer possesses enough tropical qualities to be considered a tropical cyclone. The word may refer to a former tropical cyclone undergoing extratropical transition or a tropical cyclone degenerating into a remnant low-pressure area, low. A tropical cyclone degenerating into a Trough (meteorology), trough or wave, or having it's low level circulation dissipate overland, lacks a cyclonic circulation and is referred as remnants instead of a post-tropical cyclone. However, post-tropical cyclones or remnants can continue producing high winds and heavy rains. Classification Classes Two classes of post-tropical cyclones exist * Extratropical cyclone, which is Weather front, frontal, sometimes still retains winds of Saffir–Simpson scale, hurricane or tropical storm force. Hurricane Paulette (2020) provides a recent example of an extratropical cyclone, in which it no longer has a warm core in higher latitudes when it was ove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
East Africa Time
East Africa Time, or EAT, is a time zone used in eastern Africa. The time zone is three hours ahead of UTC ( UTC+03:00), which is the same as Moscow Time, Arabia Standard Time, Further-eastern European Time and Eastern European Summer Time. As this time zone is predominantly in the equatorial region, there is no significant change in day length throughout the year and so daylight saving time is not observed. East Africa Time is observed by the following countries: * * * * * * * * * See also *Moscow Time, an equivalent time zone covering Belarus, Turkey and most of European Russia, also at UTC+03:00 *Arabia Standard Time, an equivalent time zone covering Bahrain, Iraq, Kuwait, Qatar, Saudi Arabia and Yemen, also at UTC+03:00 * Eastern European Summer Time, an equivalent time zone covering European and Middle Eastern countries during daylight saving, also at UTC+03:00 *Israel Summer Time, an equivalent time zone covering the State of Israel during daylight saving, also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sambava
Sambava is a city and commune (commune urbaine; mg, kaominina) at the east coast of northern Madagascar. It is the capital of Sambava District and Sava Region. The population of the commune was 84,039 in as of the 2018 commune census. Infrastructure Sambava is located on Route Nationale 5a Ambilobe - Antalaha. It has a local airport, regional airport. In addition to primary schooling the town offers secondary education at both junior and senior levels. The town provides access to hospital services to its citizens. Economy Farming and raising livestock provides employment for 45% and 0.5% of the working population. The most important crop is vanilla, while other important products are coconut and rice. Industry and services provide employment for 0.5% and 53.5% of the population, respectively. Additionally fishing employs 0.5% of the population. Sambava disposes of white, sandy beaches with several hotels. The Marojejy National Park is close to Sambava on the road to An ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eyewall Replacement Cycle
In meteorology, eyewall replacement cycles, also called concentric eyewall cycles, naturally occur in intense tropical cyclones, generally with winds greater than , or major hurricanes ( Category 3 or above). When tropical cyclones reach this intensity, and the eyewall contracts or is already sufficiently small, some of the outer rainbands may strengthen and organize into a ring of thunderstorms—a new, outer eyewall—that slowly moves inward and robs the original, inner eyewall of its needed moisture and angular momentum. Since the strongest winds are in a tropical cyclone's eyewall, the storm usually weakens during this phase, as the inner wall is "choked" by the outer wall. Eventually the outer eyewall replaces the inner one completely, and the storm may re-intensify. The discovery of this process was partially responsible for the end of the U.S. government's hurricane modification experiment Project Stormfury. This project set out to seed clouds outside the eyewall, appa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Surface Temperature
Sea surface temperature (SST), or ocean surface temperature, is the ocean temperature close to the surface. The exact meaning of ''surface'' varies according to the measurement method used, but it is between and below the sea surface. Air masses in the Earth's atmosphere are highly modified by sea surface temperatures within a short distance of the shore. Localized areas of heavy snow can form in bands downwind of warm water bodies within an otherwise cold air mass. Warm sea surface temperatures are known to be a cause of tropical cyclogenesis over the Earth's oceans. Tropical cyclones can also cause a cool wake, due to turbulent mixing of the upper of the ocean. SST changes diurnally, like the air above it, but to a lesser degree. There is less SST variation on breezy days than on calm days. In addition, ocean currents such as the Atlantic Multidecadal Oscillation (AMO), can affect SST's on multi-decadal time scales, a major impact results from the global thermohaline ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Outflow (meteorology)
Outflow, in meteorology, is air that flows outwards from a storm system. It is associated with ridging, or anticyclonic flow. In the low levels of the troposphere, outflow radiates from thunderstorms in the form of a wedge of rain-cooled air, which is visible as a thin rope-like cloud on weather satellite imagery or a fine line on weather radar imagery. For observers on the ground, a thunderstorm outflow boundary often approaches in otherwise clear skies as a low, thick cloud that brings with it a gust front. Low-level outflow boundaries can disrupt the center of small tropical cyclones. However, outflow aloft is essential for the strengthening of a tropical cyclone. If this outflow is restricted or undercut, the tropical cyclone weakens. If two tropical cyclones are in close proximity, the upper-level outflow from the upwind system can limit the development of the other system. Thunderstorms For thunderstorms, outflow tends to indicate the development of a system. Large q ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eye (cyclone)
The eye is a region of mostly calm weather at the center of tropical cyclones. 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 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 the location of the storm's minimum barometric pressure—where the atmospheric p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subtropical Ridge
The horse latitudes are the latitudes about 30 degrees north and south of the Equator. They are characterized by sunny skies, calm winds, and very little precipitation. They are also known as subtropical ridges, or highs. It is a high-pressure area at the divergence of trade winds and the westerlies. Origin of the term A likely and documented explanation is that the term is derived from the "dead horse" ritual of seamen (see Beating a dead horse). In this practice, the seaman paraded a straw-stuffed effigy of a horse around the deck before throwing it overboard. Seamen were paid partly in advance before a long voyage, and they frequently spent their pay all at once, resulting in a period of time without income. If they got advances from the ship's paymaster, they would incur debt. This period was called the "dead horse" time, and it usually lasted a month or two. The seaman's ceremony was to celebrate having worked off the "dead horse" debt. As west-bound shipping from Eu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saffir–Simpson Scale
The Saffir–Simpson hurricane wind scale (SSHWS) classifies hurricanes—which in the Western Hemisphere are tropical cyclones that exceed the intensities of tropical depressions and tropical storms—into five categories distinguished by the intensities of their sustained winds. This measuring system was formerly known as the Saffir–Simpson hurricane scale, or SSHS. To be classified as a hurricane, a tropical cyclone must have one-minute-average maximum sustained winds at 10 m above the surface of at least 74 mph (64 kn, 119 km/h; Category 1). The highest classification in the scale, Category 5, consists of storms with sustained winds of at least 157 mph (137 kn, 252 km/h). The classifications can provide some indication of the potential damage and flooding a hurricane will cause upon landfall. The Saffir–Simpson hurricane wind scale is based on the highest wind speed averaged over a one-minute interval 10 m above t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convection
Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convection is unspecified, convection due to the effects of thermal expansion and buoyancy can be assumed. Convection may also take place in soft solids or mixtures where particles can flow. Convective flow may be transient (such as when a multiphase mixture of oil and water separates) or steady state (see Convection cell). The convection may be due to gravitational, electromagnetic or fictitious body forces. Heat transfer by natural convection plays a role in the structure of Earth's atmosphere, its oceans, and its mantle. Discrete convective cells in the atmosphere can be identified by clouds, with stronger convection resulting in thunderstorms. Natural convection also plays a role in stellar physics. Convection is often categor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
