[kuh n-vek-shuh n] /kənˈvɛk ʃən/
Physics. the transfer of heat by the circulation or movement of the heated parts of a liquid or gas.
Meteorology. the vertical transport of atmospheric properties, especially upward (distinguished from ).
the act of conveying or transmitting.
a process of heat transfer through a gas or liquid by bulk motion of hotter material into a cooler region Compare conduction (sense 1)
(meteorol) the process by which masses of relatively warm air are raised into the atmosphere, often cooling and forming clouds, with compensatory downward movements of cooler air
(geology) the slow circulation of subcrustal material, thought to be the mechanism by which tectonic plates are moved
1620s, from Latin convectionem (nominative convectio) “the act of carrying,” noun of action from past participle stem of convehere “to carry together,” from com- “together” (see com-) + vehere “to carry” (see vehicle). Related: Convective. Convection current recorded from 1868.
convection con·vec·tion (kən-věk’shən)
Current in a fluid caused by uneven distribution of heat. For example, air on a part of the Earth’s surface warmed by strong sunlight will be heated by contact with the ground and will expand and flow upward, creating a region of low pressure below it; cooler surrounding air will then flow in to this low pressure region. The air thus circulates by convection, creating winds. See Note at conduction.
The motion of warm material that rises, cools off, and sinks again, producing a continuous circulation of material and transfer of heat. Some examples of processes involving convection are boiling water, in which heat is transferred from the stove to the air; the circulation of the atmosphere of the Earth, transferring heat from the equator to the North Pole and South Pole; and plate tectonics, in which heat is transferred from the interior of the Earth to its surface.
noun, Physics. 1. a distinct volume of circulating fluid, in a fluid medium under gravity, that is heated from below and cooled from above: usually found in large groupings. noun a self-contained zone in which warmer air in the center is pushed upward and is balanced by the downward motion of cooler air on the […]
noun 1. a gas, electric, or microwave oven equipped with a fan that circulates and intensifies the heat, thereby decreasing the normal cooking time.
- Convection zone
convection zone A region of turbulent plasma between a star’s core and its visible photosphere at the surface, through which energy is transferred by convection. In the convection zone, hot plasma rises, cools as it nears the surface, and falls to be heated and rise again.
noun, Meteorology. 1. any manifestation of convection in the atmosphere, as hail or thunderstorms.