Thermal
Translation- Thermal
A thermal column (or thermal) is a column of rising
air in the lower altitudes of theEarth's atmosphere . Thermals are created by the uneven heating of the Earth's surface fromsolar radiation , and an example ofconvection . The Sun warms the ground, which in turn warms the air directly above it.The warmer air expands, becoming less dense than the surrounding air mass. The mass of lighter air rises, and as it does, it cools due to its expansion at lower high-altitude pressures. It stops rising when it has cooled to the same temperature as the surrounding air. Associated with a thermal is a downward flow surrounding the thermal column. The downward moving exterior is caused by colder air being displaced at the top of the thermal.
The
size and strength of thermals are influenced by the properties of the lower atmosphere (the "troposphere "). Generally, when the air is cold, bubbles of warm air formed by the ground heating the air above it, can rise like a hot air balloon. The air is then said to be unstable. If there is a warm layer of air higher up, an inversion can prevent thermals from rising high and the air is said to be stable.Thermals on the Sun typically form hexagonal prisms (Bénard cells).
Thermals are often indicated by the presence of visible cumulus
clouds . When a steady wind is present thermals and their respective cumulus clouds can align in rows oriented with wind direction. Cumulus clouds formed by the rising air in a thermal as it cools and ascends, until thewater vapor in the air begins tocondense into visible droplets. The condensing water releaseslatent heat energy allowing the air to rise higher. Very unstable air can reach thelevel of free convection (LFC) and thus rise to great heights condensing large quantities of water and so forming showers or even thunderstorms.Thermals are one of the many sources of lift used by
soaring birds andgliders to soar.A similar phenomenon can be seen in a
lava lamp .ee also
*
Hot tower
*Vertical draft
*Atmospheric thermodynamics External links
* [http://cires.colorado.edu/~angevine/thermals_2006.htm What do thermals look like?] - "Thermal Structure and Behavior" by Wayne M. Angevine
* [http://bookergc.blogspot.com/2008/04/thermal-formation-and-decay.html Time-lapse video of clouds caused by thermals forming and decaying]
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thermal — 1> обыкн. pl. спец. восходящий поток теплого воздуха 2> теплый, горячий; термальный Ex: thermal spring горячий источник 3> бурный, пламенный, страстный 4> тепловой Ex: thermal shock тепловой удар Ex: thermal capacity физ. теплоемкость Ex: thermal … Новый большой англо-русский словарь
Thermal — Ther mal, a. [L. thermae hot springs, fr. Gr. ?, pl. of ? heat, fr. ? hot, warm, ? to warm, make hot; perhaps akin to L. formus warm, and E. forceps.] 1. Of or pertaining to heat; warm; hot; as, the thermal unit; thermal waters. [1913 Webster]… … The Collaborative International Dictionary of English
thermal — adj. 1) термический, тепловой; калорический 2) горячий, термальный(об источнике) … Англо-русский словарь Мюллера
Thermal — Thermal, warme Quellen betreffend od. dazu gehörig. Daher Thermalbäder, so v.w. Thermae … Pierer's Universal-Lexikon
thermal — 1) термический 2) радиотепловой 3) теплосиловой 4) термальный 5) термозэрозольный 6) термоопреснительный 7) термошумовой 8) термо 9)… … Англо-русский технический словарь
thermal — I. adjective Etymology: Greek thermē Date: 1756 1. [Latin thermae public baths, from Greek thermai, plural of thermē] of, relating to, or marked by the presence of hot springs < thermal waters > 2. a. of, relating to, or caused by heat < th … New Collegiate Dictionary
thermal — thermally, adv. /therr meuhl/, adj. 1. Also, thermic. of, pertaining to, or caused by heat or temperature: thermal capacity. 2. of, pertaining to, or of the nature of thermae: thermal waters. 3. designed to aid in or promote the retention of body … Universalium
thermal — ˈθə:məl прил. 1) термический, тепловой; калорический Syn : thermic, heat 2) горячий, термальный (об источнике) обыкн. pl (специальное) восходящий поток теплого воздуха теплый, горячий; … Большой англо-русский и русско-английский словарь
thermal — adj (fém thermale) тёплый, термальный (о минеральных водах) établissement thermal ванны, водолечебница station thermale курорт с минеральными водами … Большой французско-русский и русско-французский словарь
thermal — 1. noun /θɝɻməɫ/ A column of rising air in the lower atmosphere created by uneven heating of Earths surface. Syn: thermal column 2. adjective /θɝɻməɫ/ a) pertaining to heat or temperature … Wiktionary
Фильмы
- A working Man., 1974 — Annotation: A film tells about Yegor Borovskyy, a team leader of heavy block mounters at the hydro power station in the city of Ryazan. Film description: Film about the team of fitters E. Bohr…
- New Time Of the Old City., 1986 — Annotation: About changes, which took place at the Production Association "Chaika" ["Seagull"], producing watches, with the arrival of the new director B. Limonov. Film description: Production…
- Twelve., 1997 — Annotation: The film tells about the 1st Moscow Symposium on the stone, in which 12 renowned sculptors. Film description: The film tells about Shatura, Shatura TPP (thermal power district). Types…