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1999–2000 South-West Indian Ocean Cyclone Season
The 1999–2000 South-West Indian Ocean tropical cyclone season was the first on record in which two storms – Cyclone Leon–Eline, Leon–Eline and Cyclone Hudah, Hudah – struck Mozambique at tropical cyclone scales#South-West Indian Ocean, tropical cyclone intensity, or with maximum sustained winds of at least . The most notable storm of the season was Eline, which was the third longest-lasting storm on record in the basin. It lasted for 29 days while traversing the southern Indian Ocean, making the strongest landfall in decades along eastern Madagascar in late February. The storm was the first in a series of three storms that struck the country in early 2000, along with Gloria in March and Hudah in April. Collectively, the three storms killed at least 316 people. The season started on November 1, 1999, and ended for most of the basin on April 30, 2000; for Mauritius and the Seychelles, the season continued until May 15. These dates conventionally de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclone Hudah
Very Intense Tropical Cyclone Hudah was a powerful and destructive tropical cyclone that affected Southeast Africa in April 2000. It was the last in a series of three cyclones that impacted Madagascar during the year. Hudah first developed as a disturbance embedded within the monsoon trough on 22 March, within the Tropical cyclone basins#Australian region, Australian region cyclone basin. Moving westward as the result of a strong subtropical ridge (meteorology), ridge to its south, the storm quickly intensified, and reached Tropical cyclone scales#Australia and Fiji, Category 2 cyclone intensity on 25 March before entering the Tropical cyclone basins#South-West Indian Ocean, Southwest Indian cyclone basin. For various reasons that remain unknown, the cyclone was only designated a name by the time it had crossed into the area of responsibility of the Regional Specialized Meteorological Center in Réunion. Nonetheless, Météo-France (MFR) assigned the name ''Hudah'' to the cyclone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclone Leon-Eline
In meteorology, a cyclone () is a large air mass that rotates around a strong center of low atmospheric pressure, counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere as viewed from above (opposite to an anticyclone). Cyclones are characterized by inward-spiraling winds that rotate about a zone of low pressure. The largest low-pressure systems are polar vortices and extratropical cyclones of the largest scale (the synoptic scale). Warm-core cyclones such as tropical cyclones and subtropical cyclones also lie within the synoptic scale. Mesocyclones, tornadoes, and dust devils lie within the smaller mesoscale. Upper level cyclones can exist without the presence of a surface low, and can pinch off from the base of the tropical upper tropospheric trough during the summer months in the Northern Hemisphere. Cyclones have also been seen on extraterrestrial planets, such as Mars, Jupiter, and Neptune. Cyclogenesis is the process of cyclone formation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diego Garcia
Diego Garcia is the largest island of the Chagos Archipelago. It has been used as a joint UK–U.S. military base since the 1970s, following the expulsion of the Chagossians by the UK government. The Chagos Islands are set to become a former British Overseas Territories, British overseas territory — a treaty to transfer sovereignty from the UK to Mauritius was signed on 22 May 2025, with a provision that the military base at the island would remain under British control for at least 99 years. Located just south of the equator in the central Indian Ocean, Diego Garcia lies east of Tanzania, east-southeast of Somalia, south of the Maldives, southwest of India, west-southwest of Sumatra, northwest of Australia, and northeast of Mauritius#Mauritius_Island, Mauritius Island. Diego Garcia is part of the Chagos–Laccadive Ridge, Chagos-Laccadive Ridge, an underwater mountain range that includes the Lakshadweep, the Maldives, and the other 60 small islands of the Chagos Archi ... [...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] |
Ridge (meteorology)
In meteorology a ridge or barometric ridge is an elongated area of relatively high atmospheric pressure compared to the surrounding environment, without being a closed circulation. It is associated with an area of maximum anticyclonic curvature of wind flow. The ridge originates in the center of an anticyclone and sandwiched between two low-pressure areas, and the locus of the maximum curvature is called the ''ridge line''. This phenomenon is the opposite of a trough. Description Ridges can be represented in two ways: * On surface weather maps, the pressure isobars form contours where the maximum pressure is found along the axis of the ridge. * In upper-air maps, geopotential height isohypses form similar contours where the maximum defines the ridge. Related weather Given the direction of the winds around an anticyclonic circulation and the fact that weather systems move from west to east: *ahead of an upper-ridge, the airflow that comes from the polar regions and bri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropical Cyclone Naming
Tropical cyclones and subtropical cyclones are named by various warning centers to simplify communication between forecasters and the general public regarding forecasts, watches and warnings. The names are intended to reduce confusion in the event of concurrent storms in the same Tropical cyclone basins, basin. Once storms develop sustained wind speeds of more than , names are generally assigned to them from predetermined lists, depending on the basin in which they originate. Some tropical depressions are named in the Western Pacific, while tropical cyclones must contain a significant amount of gale-force winds before they are named in the Southern Hemisphere. Before it became standard practice to give Given name, personal (first) names to tropical cyclones, they were named after places, objects, or the saints' feast days on which they occurred. Credit for the first usage of personal names for weather systems is generally given to Queensland Government meteorologist Clement Wr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gale
A gale is a strong wind; the word is typically used as a descriptor in nautical contexts. The U.S. National Weather Service defines a gale as sustained surface wind moving at a speed between .National Weather Service Glossary s.v "gale" Forecasters typically issue s when winds of this strength are expected. In the , a gale warning is specifically a maritime warning; the land-based equivalent in National Weather Service ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
QuikSCAT
The NASA QuikSCAT (Quick Scatterometer) was an Earth observation satellite carrying the SeaWinds scatterometer. Its primary mission was to measure the surface wind speed and direction over the ice-free global oceans via its effect on water waves. Observations from QuikSCAT had a wide array of applications, and contributed to climatological studies, weather forecasting, meteorology, oceanographic research, marine safety, commercial fishing, tracking large icebergs, and studies of land and sea ice, among others. This SeaWinds scatterometer is referred to as the QuikSCAT scatterometer to distinguish it from the nearly identical SeaWinds scatterometer flown on the ADEOS-2 satellite. Mission description QuikSCAT was launched on 19 June 1999 with an initial 3-year mission requirement. QuikSCAT was a "quick recovery" mission replacing the NASA Scatterometer (NSCAT), which failed prematurely in June 1997 after just 9.5 months in operation. QuikSCAT, however, far exceeded these design expe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropical Cyclogenesis
Tropical cyclogenesis is the development and strengthening of a tropical cyclone in the atmosphere. The mechanisms through which tropics, tropical cyclogenesis occur are distinctly different from those through which temperate cyclogenesis occurs. Tropical cyclogenesis involves the development of a warm core, warm-core cyclone, due to significant convection in a favorable atmospheric environment. Tropical cyclogenesis requires six main factors: sufficiently warm sea surface temperatures (at least ), atmospheric instability, high humidity in the lower to middle levels of the troposphere, enough Coriolis force to develop a low-pressure area, low-pressure center, a pre-existing low-level focus or disturbance, and low vertical wind shear. Tropical cyclones tend to develop during the summer, but have been noted in nearly every month in tropical cyclone basins, most basins. Climate cycles such as ENSO and the Madden–Julian oscillation modulate the timing and frequency of tropical c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joint Typhoon Warning Center
The Joint Typhoon Warning Center (JTWC) is a joint United States Navy – United States Air Force command in Pearl Harbor, Hawaii. The JTWC is responsible for the issuing of tropical cyclone warnings in the North-West Pacific Ocean, South Pacific Ocean, and Indian Ocean for all branches of the U.S. Department of Defense and other U.S. government agencies. Their warnings are intended primarily for the protection of U.S. military ships and aircraft, as well as military installations jointly operated with other countries around the world. Its U.S. Navy components are aligned with the Naval Meteorology and Oceanography Command. History The origins of the Joint Typhoon Warning Center (JTWC) can be traced back to June 1945, when the Fleet Weather Center/Typhoon Tracking Center was established on the island of Guam, after multiple typhoons, including Typhoon Cobra of December 1944 and Typhoon Connie in June 1945, had caused a significant loss of men and ships. At this time th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longitude
Longitude (, ) is a geographic coordinate that specifies the east- west position of a point on the surface of the Earth, or another celestial body. It is an angular measurement, usually expressed in degrees and denoted by the Greek letter lambda (λ). Meridians are imaginary semicircular lines running from pole to pole that connect points with the same longitude. The prime meridian defines 0° longitude; by convention the International Reference Meridian for the Earth passes near the Royal Observatory in Greenwich, south-east London on the island of Great Britain. Positive longitudes are east of the prime meridian, and negative ones are west. Because of the Earth's rotation, there is a close connection between longitude and time measurement. Scientifically precise local time varies with longitude: a difference of 15° longitude corresponds to a one-hour difference in local time, due to the differing position in relation to the Sun. Comparing local time to an absol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maximum Sustained Winds
The maximum sustained wind associated with a tropical cyclone is a common indicator of the intensity of the storm. Within a mature tropical cyclone, it is found within the eyewall at a certain distance from the center, known as the radius of maximum wind, or RMW. Unlike gusts, the value of these winds are determined via their sampling and averaging the sampled results over a period of time. Wind measuring has been standardized globally to reflect the winds at above mean sea level, and the maximum sustained wind represents the highest average wind over either a one-minute (US) or ten-minute time span (see the definition, below), anywhere within the tropical cyclone. Surface winds are highly variable due to friction between the atmosphere and the Earth's surface, as well as near hills and mountains over land. Over the ocean, satellite imagery is often used to estimate the maximum sustained winds within a tropical cyclone. Land, ship, aircraft reconnaissance observations, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
