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Hurricane Genevieve (2014)
Hurricane Genevieve, also referred to as Typhoon Genevieve, was the first tropical cyclone to track across all three northern Pacific basins since Hurricane Dora in 1999. Genevieve developed from a tropical wave into the eighth tropical storm of the 2014 Pacific hurricane season well east-southeast of Hawaii on July 25. However, increased vertical wind shear caused it to weaken into a tropical depression by the following day and degenerate into a remnant low on July 28. Late on July 29, the system regenerated into a tropical depression, but it weakened into a remnant low again on July 31, owing to vertical wind shear and dry air. The remnants redeveloped into a tropical depression and briefly became a tropical storm south of Hawaii on August 2, yet it weakened back into a tropical depression soon afterwards. Late on August 5, Genevieve re-intensified into a tropical storm, and intensified into a Category 1 hurricane on the next day when undergoing rapid deepening because of favo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2014 Pacific Hurricane Season
The 2014 Pacific hurricane season was the fifth-busiest season since reliable records began in 1949, alongside the 2016 season. The season officially started on May 15 in the East Pacific Ocean, and on June 1 in the Central Pacific; they both ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Pacific basin. Entering the season, expectations of tropical activity were high, with most weather agencies predicting a near or above average season. The season began with an active start, with three tropical cyclones developing before June 15, including two Category 4 hurricanes, of which one became the strongest tropical cyclone ever recorded in May in the East Pacific. After a less active period in late June and early July, activity once again picked up in late July. Activity increased in August, which featured four major hurricanes, and persisted throughout September and October. However, activ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocean Prediction Center
The Ocean Prediction Center (OPC), established in 1995, is one of the National Centers for Environmental Prediction's (NCEP's) original six service centers. Until 2003, the name of the organization was the Marine Prediction Center.Ocean Prediction Center (2004)Ocean Prediction Center: 2003 Accomplishments. Retrieved on 2008-09-03. Its origins are traced back to the sinking of the RMS ''Titanic'' in 1912. The OPC issues forecasts up to five days in advance for ocean areas north of 31° north latitude and west of 35° west longitude in the Atlantic, and across the northeast Pacific north of 30° north latitude and east of 160° east longitude. Until recently, the OPC provided forecast points for tropical cyclones north of 20° north latitude and east of the 60° west longitude to the National Hurricane Center. OPC is composed of two branches: the Ocean Forecast Branch and the Ocean Applications Branch. History The first attempt as a marine weather program within the Unit ... [...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. Tropic ... [...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 tropical cyclogenesis occurs are distinctly different from those through which temperate cyclogenesis occurs. Tropical cyclogenesis involves the development of a 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 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 most basins. Climate cycles such as ENSO and the Madden–Julian oscillation modulate the timing and frequency of tropical cyclone development. There is a limit on tropical cyclone i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Pacific Hurricane Center
The Central Pacific Hurricane Center (CPHC) of the United States National Weather Service is the official body responsible for tracking and issuing tropical cyclone warnings, watches, advisories, discussions, and statements for the Central Pacific region: from the equator northward, 140°W–180°W, most significantly for Hawai‘i. It is the Regional Specialized Meteorological Center (RSMC) for tropical cyclones in this region, and in this capacity is known as RSMC Honolulu. Based in Honolulu, Hawaii, the CPHC is co-located with the National Weather Service's Honolulu forecast office on the campus of the University of Hawaii at Mānoa. The Honolulu forecast office activates the CPHC when tropical cyclones form in, or move into, the Central Pacific region. The CPHC replaced the previous forecaster, the Joint Hurricane Warning Center, starting in the 1970 season. Area of responsibility The CPHC's area of responsibility is the Central Pacific (CP) region, which is an administra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
140th Meridian West
The meridian 140° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, North America, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole. The line is the divider in the area of warning responsibility between the National Hurricane Center and the Central Pacific Hurricane Center in the north Pacific Ocean. The 140th meridian west forms a great circle with the 40th meridian east. From Pole to Pole Starting at the North Pole and heading south to the South Pole, the 140th meridian west passes through: : See also * 139th meridian west *141st meridian west The meridian 141° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, North America, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole. The 141st meridian west forms a grea ... References {{DEFAULTSORT:140th Meridian West w140 meridian west ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Circulation
Atmospheric circulation is the large-scale movement of 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 – mid-latitude 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 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 it redistributes the energy absorbed by the Earth's surface near ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intertropical Convergence Zone
The Intertropical Convergence Zone (ITCZ ), known by sailors as the doldrums or the calms because of its monotonous windless weather, is the area where the northeast and the southeast trade winds converge. It encircles Earth near the thermal equator though its specific position varies seasonally. When it lies near the geographic Equator, it is called the near-equatorial trough. Where the ITCZ is drawn into and merges with a monsoonal circulation, it is sometimes referred to as a monsoon trough, a usage that is more common in Australia and parts of Asia. Meteorology The ITCZ was originally identified from the 1920s to the 1940s as the ''Intertropical Front'' (''ITF''), but after the recognition in the 1940s and the 1950s of the significance of wind field convergence in tropical weather production, the term ''Intertropical Convergence Zone'' (''ITCZ'') was then applied. The ITCZ appears as a band of clouds, usually thunderstorms, that encircle the globe near the Equator. In the ... [...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 Subtropics, 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 Flogging a dead horse#Earlier meaning, 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 "d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genevieve 2014-07-25 2205Z
Genevieve (french: link=no, Sainte Geneviève; la, Sancta Genovefa, Genoveva; 419/422 AD – 502/512 AD) is the patroness saint of Paris in the Catholic and Orthodox traditions. Her feast is on 3 January. Genevieve was born in Nanterre and moved to Paris (then known as Lutetia) after encountering Germanus of Auxerre and Lupus of Troyes and dedicated herself to a Christian life.McNamara, Halborg, and Whatley 18. In 451 she led a "prayer marathon" that was said to have saved Paris by diverting Attila's Huns away from the city. When the Germanic king Childeric I besieged the city in 464, Genevieve acted as an intermediary between the city and its besiegers, collecting food and convincing Childeric to release his prisoners. Her following and her status as patron saint of Paris were promoted by Clotilde, who may have commissioned the writing of her ''vita''. This was most likely written in Tours, where Clotilde retired after her husband's death, as evidenced also by the importan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scatterometer
A scatterometer or diffusionmeter is a scientific instrument to measure the return of a beam of light or radar waves scattered by diffusion in a medium such as air. Diffusionmeters using visible light are found in airports or along roads to measure horizontal visibility. Radar scatterometers use radio or microwaves to determine the normalized radar cross section (σ0, "sigma zero" or "sigma naught") of a surface. They are often mounted on weather satellites to find wind speed and direction, and are used in industries to analyze the roughness of surfaces. Optical Optical diffusionmeters are devices used in meteorology to find the optical range or the horizontal visibility. They consist of a light source, usually a laser, and a receiver. Both are placed at a 35° angle downward, aimed at a common area. Lateral scattering by the air along the light beam is quantified as an attenuation coefficient. Any departure from the clear air extinction coefficient (e.g. in fog) is measured an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Convection
Atmospheric convection is the result of a parcel-environment instability, or temperature difference layer in the atmosphere. Different lapse rates within dry and moist air masses lead to instability. Mixing of air during the day which expands the height of the planetary boundary layer leads to increased winds, cumulus cloud development, and decreased surface dew points. Moist convection leads to thunderstorm development, which is often responsible for severe weather throughout the world. Special threats from thunderstorms include hail, downbursts, and tornadoes. Overview There are a few general archetypes of atmospheric instability that are used to explain convection (or lack thereof). A necessary (but not sufficient) condition for convection is that the environmental lapse rate (the rate of decrease of temperature with height) is steeper than the lapse rate experienced by a rising parcel of air. When this condition is met, upward-displaced air parcels can become buoyant and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
