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rain

(Encyclopedia)rain, precipitation in liquid form. It consists of drops of water falling from clouds; if the drops are very small, they are collectively termed drizzle. Rain plays a key role in the hydrologic, or wa...

tornado

(Encyclopedia)tornado, dark, funnel-shaped cloud containing violently rotating air that develops below a heavy cumulonimbus cloud mass and extends toward the earth. The funnel twists about, rises and falls, and whe...

ice plant

(Encyclopedia)ice plant, low, fleshy plant (Cryophytum crystalinum) of warm, dry, barren regions. It is cultivated chiefly as a curiosity because of its leaves, densely coated with small, glistening, bladder-shaped...

doldrums

(Encyclopedia)doldrums dŏlˈdrəmz [key] or equatorial belt of calms, area around the earth centered slightly north of the equator between the two belts of trade winds. The large amount of solar radiation that arr...

air traffic control

(Encyclopedia)air traffic control, the system by which airplanes are safely routed into and out of major airports. Air traffic control in the United States is centered in a number of regional control centers that r...

air-cushion vehicle

(Encyclopedia)CE5 Air-cushion vehicle: In vehicles modified with a trunk or skirt (A), the rate of leakage is reduced and less power is needed to maintain the cushion. Vehicles designed to travel over deep water...

Strategic Air Command

(Encyclopedia)Strategic Air Command (SAC), former command of the U.S. air force (see Air Force, United States Department of the) charged with organizing, training, equipping, administering, and preparing strategic ...

rainmaking

(Encyclopedia)rainmaking, production of rain by artificial means now generally disregarded, though it is probable that rainmaking hastens or increases rainfall from clouds suitable for natural rainfall. Interest in...

psychrometer

(Encyclopedia)psychrometer sīkrŏmˈĭtər [key], one of many instruments used for measuring the water vapor content or relative humidity of the atmosphere. It consists of two identical thermometers—the wet-bulb...

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