Page:Dictionary of aviation.djvu/206

 182 DICTIONARY OF AVIATION

monsoon rain, a rain accompanying or due to a monsoon wind.

luminous rain, rain characterized by luminous electric discharges or sparks between the drops or between the deeps and the ground.

orographic rain, rain which is due to the cooling of air by expansion when deflected upward by hills or mountains.

yellow rain, rain due to the pellen of fir^tjees, etc., be- ing raised by the wind and afterwards precipitated ; sul- fur^rain. rain-area 'zeen,e:-zi-3 n.

1. an area or region of the earth over which rain is falling or has fallen, as one of those shown on a wether^ map.

2. the area or region of an extensiv cyclone in which the maximum rainfall occurs, as one of the southerly quadrants, in the northern hemisfere, or a northerly quadrant in the southerly hemisfere.

3. the area or tjact of a sterm^area where rain is falling, as distinguisht from the area where snow is falling.

rainball 'zeen,bc:} n. (in England) one of the festoons of mammato^cumulus or pocky cloud, considerd as being a sign of rain.

rainband 'zeen,baend n. a dark band in the solar spectrum due to absorption of light by the water^vapor in the at- mosfere, studied by means of a spectroscope in forecasting wether.

rain-bearing 'zeen,be:-zirj adj. having, producing, or bring- ing rain : said of winds.

rain-belt 'zeen,beh n. a belt or elongated region where rain is relativly frequent; a tract where the rainfall is greater than in surrounding relativly and tracts.

equatorial rainzbelt, the rain^belt which girdles the earth in the equatorial region and is containd by the somewhat wider zone known as the equatorial cloud^belt.

rain-bird 'zeen,bt3:zd n. a bird, as the rain^crow, which is supposed to indicate rain by its noisy or uneasy actions, compare stormibird.

rainbow 'zeen,boo n. a bow or arch exhibiting the colors of the solar spectrum in concentric bands, formd in the sky epposit the sun, by the reflection, double refraction, and dispersion of the sun's rays in falling rain^dreps; also, a similar arch in the spray of cataracts, breakers, and the like.

moonlight rainbow, a dim rainbow occurring by moon- light.

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