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Vicky Pope is a scientist and the former head of the climate predictions programme at the Hadley Centre.
A hook echo is a pendant or hook-shaped weather radar signature as part of some supercell thunderstorms. It is found in the lower portions of a storm as air and precipitation flow into a mesocyclone, resulting in a curved feature of reflectivity. The echo is produced by rain, hail, or even debris being wrapped around the supercell. It is one of the classic hallmarks of tornado-producing supercells. The National Weather Service may consider the presence of a hook echo coinciding with a tornado vortex signature as sufficient to justify issuing a tornado warning.
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The Lemon technique is a method used by meteorologists using weather radar to determine the relative strength of thunderstorm cells in a vertically sheared environment. It is named for Leslie R. Lemon, the co-creator of the current conceptual model of a supercell. The Lemon technique is largely a continuation of work by Keith A. Browning, who first identified and named the supercell.
Tornadogenesis is the process by which a tornado forms. There are many types of tornadoes and these vary in methods of formation. Despite ongoing scientific study and high-profile research projects such as VORTEX, tornadogenesis is a volatile process and the intricacies of many of the mechanisms of tornado formation are still poorly understood.
Horizontal convective rolls, also known as horizontal roll vortices or cloud streets, are long rolls of counter-rotating air that are oriented approximately parallel to the ground in the planetary boundary layer. Although horizontal convective rolls, also known as cloud streets, have been clearly seen in satellite photographs for the last 30 years, their development is poorly understood, due to a lack of observational data. From the ground, they appear as rows of cumulus or cumulus-type clouds aligned parallel to the low-level wind. Research has shown these eddies to be significant to the vertical transport of momentum, heat, moisture, and air pollutants within the boundary layer. Cloud streets are usually more or less straight; rarely, cloud streets assume paisley patterns when the wind driving the clouds encounters an obstacle. Those cloud formations are known as von Kármán vortex streets.
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In meteorology, eyewall replacement cycles, also called concentric eyewall cycles, naturally occur in intense tropical cyclones, generally with winds greater than 185 km/h (115 mph), or major hurricanes. When tropical cyclones reach this intensity, and the eyewall contracts or is already 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.
Adrian Edmund Gill FRS was an Australian meteorologist and oceanographer best known for his textbook Atmosphere-Ocean Dynamics. Gill was born in Melbourne, Australia, and worked at Cambridge, serving as Senior Research Fellow from 1963 to 1984. His father was Edmund Gill, geologist, palaeontologist and curator at the National Museum of Victoria.
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The Spanish Plume is a weather pattern in which a plume of warm air moves from the Iberian plateau or the Sahara to northwestern Europe, causing thunderstorms. This meteorological pattern can lead to extreme high temperatures and intense rainfall during the summer months, with potential for flash flooding, damaging hail, and tornado formation. Some of these intense thunderstorms are formed from thermal lows, which are also known as heat lows. Thermal lows can be semipermanent features around some parts of Europe, particularly in the summer season. These thermal lows can be developed or created around Spain, Portugal, France etc., during the summer season because of the intense heat. Thermal low pressure can be located around the world, particularly in the summer or in tropical regions.
Margaret Anne LeMone is an atmospheric scientist who uses both atmospheric observations and computer models to study the formation and development of clouds, the development of precipitation, and the structure of storms.
Roger M. Lhermitte was a French meteorologist who "pioneered the development of meteorological Doppler radar." His career extended from the 1950s until his death where he made numerous contributions to the field of Radar Meteorology resulting in over 100 publications and numerous patents.
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References
- ↑ Browning, Keith A.; Frank H. Ludlam (April 1962). "Airflow in convective storms" (PDF). Quarterly Journal of the Royal Meteorological Society. 88 (376): 117–35. Bibcode:1962QJRMS..88..117B. doi:10.1002/qj.49708837602.; Browning, K. A.; Ludlam, F. H. (1962). "Airflow in convective storms". Quarterly Journal of the Royal Meteorological Society. 88 (378): 555. Bibcode:1962QJRMS..88..555B. doi:10.1002/qj.49708837819.
- ↑ Browning, Keith A. (November 1964). "Airflow and Precipitation Trajectories Within Severe Local Storms Which Travel to the Right of the Winds". J. Atmos. Sci. 21 (6): 634–9. Bibcode:1964JAtS...21..634B. doi:10.1175/1520-0469(1964)021<0634:AAPTWS>2.0.CO;2. hdl: 2027/mdp.39015095125533 .
- ↑ Browning, Keith (November 1965). "Some Inferences About the Updraft Within a Severe Local Storm". J. Atmos. Sci. (abstract). 22 (6): 669–77. Bibcode:1965JAtS...22..669B. doi:10.1175/1520-0469(1965)022<0669:SIATUW>2.0.CO;2. hdl: 2027/mdp.39015095128867 .
- ↑ Sting Jets in Severe Northern European Windstorms Archived 2014-03-20 at the Wayback Machine
- ↑ "Keith Browning". royalsociety.org. Retrieved 15 June 2022.
- ↑ "Fellows". Royal Society. Retrieved 20 December 2010.
