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Cyclone George
Severe Tropical Cyclone George was one of the most powerful Australian tropical cyclones on record, attaining a minimum barometric pressure of 902 mbar (hPa; 26.64 inHg). It was also the strongest tropical cyclone worldwide in 2007 and the last Australian region tropical cyclone to achieve this record to date. The cyclone formed on 26 February 2007 in the Northern Territory's Top End, and intensified when it entered the Joseph Bonaparte Gulf, before crossing the northern coast of the Kimberley. It moved over the Indian Ocean, intensifying to a Category 4 cyclone, and eventually crossed the Pilbara coast just east of Port Hedland at peak intensity. After further analysis from the Bureau of Meteorology, George was reclassified to Category 5. The cyclone caused significant damage to the town of Port Hedland and numerous isolated mining camps around the town. Losses in Northern Territory amounted to at least A$12 million (US$9.5 million). Two people died a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Territory
The Northern Territory (commonly abbreviated as NT; formally the Northern Territory of Australia) is an states and territories of Australia, Australian territory in the central and central northern regions of Australia. The Northern Territory shares its borders with Western Australia to the west (129th meridian east), South Australia to the south (26th parallel south), and Queensland to the east (138th meridian east). To the north, the territory looks out to the Timor Sea, the Arafura Sea and the Gulf of Carpentaria, including Western New Guinea and other islands of the Indonesian archipelago. The NT covers , making it the third-largest Australian federal division, and List of country subdivisions by area, the 11th-largest country subdivision in the world. It is sparsely populated, with a population of only 249,000 – fewer than half as many people as in Tasmania. The largest population center is the capital city of Darwin, Northern Territory, Darwin. The archaeological hist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low Pressure Area
In meteorology, a low-pressure area, low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. 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 second is an area where wind divergence aloft occurs a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropical Cyclone Formation Alert
A Tropical Cyclone Formation Alert (TCFA) is a bulletin released by the U.S. Navy-operated Joint Typhoon Warning Center in Honolulu, Hawaii or the Fleet Weather Center in Norfolk, Virginia, warning of the possibility of a tropical cyclone forming from a tropical disturbance that has been monitored. Such alerts are generally always issued when it is fairly certain that a tropical cyclone will form and are not always released before cyclone genesis, particularly if the cyclone appears suddenly. The TCFA consists of several different checks that are performed by the on-duty meteorologist of the system and its surroundings. If the condition being checked is met, a certain number of points are given to the system. Parts of the TCFA Section 1 The first section of the TCFA contains information on the area of the alert as well as the estimated center of the circulation. The estimated maximum sustained winds are provided as well. Section 2 The second section generally contains more specif ... [...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 for the protection of primarily 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 the center ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wind Shear
Wind shear (or 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 the control of a ... [...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 quan ... [...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] |
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] |
Milingimbi Island
Milingimbi Island, also Yurruwi, is the largest island of the Crocodile Islands group off the coast of Arnhem Land, Northern Territory, Australia. Location Milingimbi lies approximately east of Darwin, Northern Territory, Darwin and west of Nhulunbuy. History Aboriginal Australians, Aboriginal people have occupied the area for more than 40,000 years. It was an important ritual centre for the great ceremonies conducted by the indigenous inhabitants. In 1923, the Methodist Church of Australasia, Methodist Overseas Mission established a mission station, mission on the island, which attracted Aboriginal people from eastern clan groups. They included Dhuwal language, Gupapuyŋu- and Djambarrpuyŋu-, as well as Wangurri language, Wangurri- and Warramirri language, Warramirri-speaking people. The Yan-nhangu language, Yan-nhangu-speaking Yolngu people are the traditional owners of Milingimbi and its surrounding seas and islands. The island was bombed by the Japanese during World War ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gulf Of Carpentaria
The Gulf of Carpentaria (, ) is a large, shallow sea enclosed on three sides by northern Australia and bounded on the north by the eastern Arafura Sea (the body of water that lies between Australia and New Guinea). The northern boundary is generally defined as a line from Slade Point, Queensland (the northwestern corner of Cape York Peninsula) in the northeast, to Cape Arnhem on the Gove Peninsula, Northern Territory (the easternmost point of Arnhem Land) in the west. At its mouth, the Gulf is wide, and further south, . The north-south length exceeds . It covers a water area of about . The general depth is between and does not exceed . The tidal range in the Gulf of Carpentaria is between . The Gulf and adjacent Sahul Shelf were dry land at the peak of the last ice age 18,000 years ago when global sea level was around below its present position. At that time a large, shallow lake occupied the centre of what is now the Gulf. The Gulf hosts a submerged coral reef provinc ... [...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] |
Nhulunbuy
Nhulunbuy () is a township that is the sixth largest population centre in the Northern Territory of Australia. Nhulunbuy was created on the Gove Peninsula in north-east Arnhem Land when a bauxite mine and a deep water port were established in the late 1960s, followed by an alumina refinery. The alumina refinery closed in May 2014, and Nhulunbuy was reduced by 700 to 3,240 by the time of the 2016 Australian census. The median age in the town was 32 in the 2016 census. History This area in Northeast Arnhem Land has been home to the Yolngu Aboriginal people for at least 40,000 years. Matthew Flinders, in his circumnavigation of Australia in 1803, met the Macassan trading fleet near present-day Nhulunbuy, an encounter that led to the establishment of settlements on Melville Island and the Cobourg Peninsula. A beach close to the township is named Macassan Beach in honour of this encounter. In 1963, an Australian Government decision excised part of the land for a bau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
