1、BRITISH STANDARD BS 185-15: 1972 Glossary of Aeronautical and astronautical terms Section 15: Meteorology UDC 001.4:629.7:551.5BS185-15:1972 This British Standard, having been approved by the AerospaceIndustry StandardsCommittee, was published under the authority ofthe Executive Board of the Institu
2、tion on 14August1972 BSI 01-2000 The following BSI references relate to the work on this standard: Committee reference ACE/1 Draft for comment 70/30482 ISBN 0580 07395 5 A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsi
3、ble for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages1 to12 and a back cover. This standard has been updated (see copyright
4、date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsBS185-15:1972 BSI 01-2000 i Contents Page Section 15. Meteorology Subsection 151. General 1 Subsection 152. Winds 2 Subse
5、ction 153. Weather 5 Subsection 154. Clouds 5 Subsection 155. Synoptic meteorology 7 Subsection 156. Ice formation in flight 9 Subsection 157. Instruments 10 Table 1 Beaufort scale of wind force 12ii blankBS185-15:1972 BSI 01-2000 1 (Notes on the arrangement and scope of the glossary are contained i
6、n the Foreword to Section 1.) The terms included in this section are limited mainly to those used in aeronautics. For other terms and for amplification of the definitions given here, reference should be made to the Meteorological Glossary,5th Edition, published byH.M. Stationery Office. Section 15.
7、Meteorology Subsection 151. General No. Term Definition 15101 advection The process of transfer by horizontal motion in the atmosphere, e.g., the transfer of heat from low to high latitudes. 15102 atmosphere The air surrounding the Earth. 15103 International Standard atmosphere A standard atmosphere
8、 adopted internationally for useincomparing the performance of aircraft. (SeeBritishStandardG.199.) 15104 standard atmosphere Any hypothetical atmosphere the physical properties of which are given arbitrary values, approximating to mean conditions, for specific purposes. atmospheric layers a 15105 t
9、roposphere The layer of the atmosphere extending from the Earths surface to an altitude varying roughly between7.5km (25000ft) and15km (50000ft) in which temperature normally decreases with altitude. 15106 tropopause The atmospheric boundary between the troposphere and the stratosphere. 15107 strato
10、sphere The layer of the atmosphere above the troposphere and below the mesosphere in which the temperature generally increases with altitude. 15108 stratopause The atmospheric boundary between the stratosphere and the mesosphere. 15109 mesosphere That part of the atmosphere between the stratosphere,
11、 atabout50km (165000ft), and the mesopause, at about80km (260000ft), in which temperature generally decreases with altitude. 15110 mesopause The top of the mesosphere, marked by a temperature minimum. 15111 thermosphere The region above the mesopause in which temperature generally increases with alt
12、itude. 15112 atmospheric pressure The pressure produced at any point in the atmosphere by the weight of the air above it. 15113 aurora The sporadic radiant emission from the upper atmosphere over middle and high latitudes. It is liable to interfere seriously with radiocommunication. 15114 basic ther
13、mal radiation Thermal radiation from the sun at sunspot minimum. 15115 convection The process of transfer of heat and mass by vertical motion in the atmosphere. 15116 dew point The temperature to which humid air must be cooled without change of pressure or humidity mixing ratio for it to become satu
14、rated with respect to liquid water. 15117 hoar-frost point The temperature to which humid air must be cooled without change of pressure or humidity mixing ratio for it to become saturated in the presence of ice. 15118 humidity The condition of the atmosphere in respect of water vapour. 15119 humidit
15、y, mixing ratio MIXING RATIO OF MOIST AIR In any volume of air, the ratio of the mass of water vapour to the mass of dry air. a For atmospheric layers not defined herein reference should be made to the Meteorological Glossary.BS185-15:1972 2 BSI 01-2000 Subsection 152. Winds No. Term Definition 1512
16、0 relative humidity The ratio, expressed as a percentage, of the actual vapour pressure to the saturation vapour pressure over a plane liquid water surface at the same dry-bulb temperature. 15121 saturation vapour pressure The partial pressure of water vapour in equilibrium with a plane surface of w
17、ater or of ice. It increases with temperature and below0 C it is, at a given temperature, greater over supercooled water than over ice. 15122 vapour concentration The mass of water vapour per unit volume of air. 15123 inversion An increase of air temperature with altitude. 15124 lapse rate The rate
18、of decrease of air temperature with altitude. 15125 dry adiabatic lapse rate The lapse rate of dry air under adiabatic conditions (approximately1 C per100metres or5.4 F per1000feet). 15126 saturated adiabatic lapse rate The lapse rate of saturated air under adiabatic conditions. Its value varies rap
19、idly with temperature and slowly with pressure. For pressures between1050mbar and700mbar it is approximately0.5 C per100metres at10 C, or3 F per 1000 feet at50 F. surface ocean waves 15127 sea The degree of sea disturbance produced by local causes. It is reported in a “state of sea” code in which th
20、e scale number increases from0 to9according to the average wave height. 15128 swell Wave motion persisting in the sea after the disturbing cause has passed away or due to a disturbance at a distance, usually characterized by long, low, regular undulations. 15129 Synoptic meteorology The collection a
21、nd presentation of information regarding meteorological conditions over a wide area at a given time. 15130 visibility The greatest distance at which an object of specified characteristics can be seen and identified. At night, lights are observed and an equivalent day-light visibility is deduced. 152
22、01 atmospheric turbulence Random variations in the motion of the air. 15202 clear air turbulence Atmospheric turbulence, of a scale sufficient to cause bumpiness to an aircraft in flight, not associated with cloud and not ascribable directly to the frictional influence of the ground or to convection
23、 currents. 15203 convectional turbulence Atmospheric turbulence predominantly associated with varying vertical air currents caused by heating of the atmosphere adjacent to the Earths surface. 15204 cumulonimbus turbulence Intense convectional turbulence within or near cumulonimbus cloud. 15205 frict
24、ional turbulence MECHANICAL TURBULENCE Atmospheric turbulence produced by wind flow over surface irregularities. 15206 backing A counter-clockwise change of wind direction in either hemisphere. (Cf.15242.) 15207 Beaufort scale of wind force A numerical scale, ranging from0 (Calm) to12 (Hurricane), o
25、riginated by Rear-Admiral Sir Francis Beaufort for the estimation of wind force by observing its effects on common objects. (See Table 1.)BS185-15:1972 BSI 01-2000 3 No. Term Definition 15208 blizzard A high wind accompanied by extreme cold and driving snow. 15209 breeze See Beaufort scale, Table 1.
26、 15210 land breeze An off-shore wind during a clear night, caused by the more rapid cooling of the air over land than over water. 15211 mountain breeze A katabatic wind which blows down valleys and mountain slopes at night or in winter. 15212 sea breeze An on-shore wind during the day, caused by the
27、 more rapid heating of the air over land than over water. 15213 valley breeze A wind which blows up valleys and mountain slopes during the day when the sun warms the ground. 15214 calm See Beaufort scale, Table 1. 15215 doldrums The equatorial oceanic regions of calms and variable winds which are of
28、ten associated with heavy rains, thunderstorms and squalls. 15216 dust devil A small whirlwind, formed by strong convection over desert regions, which raises dust or sand in a vertical column. 15217 dust storm A squall carrying dust or fine sand extending to a height of some hundreds, possibly thous
29、ands, of metres. 15218 eye of storm The central calm area of a tropical revolving storm. 15219 fhn A warm, dry wind which blows down the leeward slopes, when the general wind current comes over mountains. 15220 gale See Beaufort scale, Table 1. 15221 geostrophic wind speed The speed of the wind calc
30、ulated from the pressure gradient, the air density, the rotational velocity of the Earth and the latitude, but neglecting the curvature of the path of the air. 15222 gradient wind speed The speed of the wind calculated as for geostrophic wind speed, but taking into account the curvature of the path
31、of the air. 15223 gust A rapid variation with time or distance in the speed or direction of the wind. 15224 gust gradient distance The horizontal distance over which the vertical velocity of a gust changes from zero to its maximum value. 15225 horse latitudes The belts of calm, light winds and fine,
32、 clear weather which lie approximately30 N and30 S of the equator between the trade-wind belts and the prevailing westerly winds of higher latitudes. 15226 hurricane wind See Beaufort scale, Table 1. 15227 jet stream A flat, tubular, quasi-horizontal current of air, the axis of which is along a line
33、 of maximum speed and which is characterized, not only by great speeds, but also by strong transverse gradients of speed. It is generally near the tropopause. 15228 Katabatic wind A local wind caused by the downward motion, due to convection, of cold air off high ground. 15229 monsoon A wind which b
34、lows, in certain regions, with great persistence and regularity in a constant direction which varies with the season of the year. 15230 rotor A large closed eddy with a horizontal axis. 15231 sandstorm A strong wind carrying dust or sand, extending over a considerable area.BS185-15:1972 4 BSI 01-200
35、0 No. Term Definition 15232 squall A strong wind which rises and dies away rapidly, lasting only for a few minutes, frequently associated with a temporary change in wind direction. 15233 line squall A squall advancing on a wide front. NOTEThe passage of a well-developed line squall, which may be hun
36、dreds of kilometres long, is usually marked by a sudden or very rapid change of wind direction, heavy rain, hail or snow, thunder and lightning, rapid rise in barometric pressure, a sudden or rapid fall of temperature, and violent vertical disturbances. A frequent characteristic is a long arch or li
37、ne of low black cloud. 15234 standing waves Ascending and descending currents associated in certain circumstances with wind flow over mountains, hills or even relatively small ridges. The waves may extend on the lee side to great distances and to several times the elevation of the obstacles. 15235 l
38、ee waves Standing waves on the lee side. 15236 storm wind See Beaufort scale, Table 1. 15237 thermal wind The vector difference between the winds at two levels due to the mean horizontal gradient of temperature in the layer of atmosphere between those levels. 15238 tornado 1.A violent whirlwind of s
39、mall radius, advancing over the land, in which winds of destructive force circulate round a centre. It forms a region of strong ascending currents and is generally made visible by a funnel cloud. 2. In West Africa, the squall accompanying a thunderstorm; it occurs most frequently during the transiti
40、on months between rainy and dry seasons. 15239 trade winds Persistent winds which blow from the horse latitudes towards the doldrums. They flow from the north-east in the northern hemisphere and from the south-east in the southern hemisphere. 15240 anti-trade winds A reverse current sometimes occurr
41、ing above the trade winds at an altitude of1000m (3000ft) or more. 15241 tropical revolving storm A small cyclonic depression, originating over tropical oceans, with strong winds, often of hurricane force, circulating counter-clockwise in the northern, and clockwise in the southern hemisphere. Known
42、 as hurricane in the West Indies, cyclone in the Indian Ocean, and Australia, and typhoon in the China seas. 15242 veering A clockwise change of wind direction in either hemisphere. (Cf.15206.) 15243 waterspout The counterpart of a tornado(1), over water. NOTEThe core is made visible by the condensa
43、tion of water drops from adiabatic cooling produced by the lowering of pressure in the core. 15244 whirlwind A small-scale rotating column of air. 15245 wind rose A diagram showing, for a definite locality, and usually for a more or less extended period, the frequency of winds of different direction
44、s and strengths. 15246 wind shear Change of wind velocity with distance along an axis at right angles to the wind direction (usually specified as vertical or horizontal).BS185-15:1972 BSI 01-2000 5 Subsection 153. Weather Subsection 154. Clouds No. Term Definition 15301 Beaufort notation A system of
45、 letters originated by Rear-Admiral Sir Francis Beaufort for recording weather phenomena. 15302 cloud seeding The dispersal of a finely divided substance in a cloud to change its development,e.g.to make rain. 15303 fog Atmospheric obscurity, produced in the surface layer by suspended water droplets,
46、 with or without smoke, in which visibility falls below1km.(In synoptic reporting “fog” is not used when the obscurity is caused by dry smoke.) 15304 ice fog Atmospheric obscurity, produced in the surface layer by numerous suspended minute ice crystals, in which visibility falls below1km. 15305 sea
47、fog Fog formed at sea, usually by condensation of moisture in the lower layers of a warm air current passing over a relatively cold sea surface. 15306 frost A condition in which the temperature of the air is below the freezing point of water. 15307 glazed frost A layer of smooth ice formed by rain f
48、alling on aircraft or other exposed object the temperature of which is below freezing point. (Cf.15607.) 15308 hoar frost See 15608. 15309 rime A deposit of ice of a feathery nature, on the windward side of exposed objects when frost and fog occur together. (Cf.15614). 15310 glaze ice See 15607. 153
49、11 haze Atmospheric obscurity due to the presence of solid matter such as dust, smoke, or hygroscopic particles carrying a deposit of water in air not saturated with water vapour. 15312 mist Atmospheric obscurity, produced in the surface layer by suspended water droplets, in which visibility remains at1km or more. 15313 precipitation A general term for the forms in which water may fall from the atmosphere. 15314 drizzle Liquid precipitation in the form of droplets so small that their individual impact on water surfaces is imperceptible. 15315 hail Precipitation in
