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Eng ID Term Definition
2241
height of cloud base
HEIGHT above the EARTH's surface, at a given point, of the base of the lowest CLOUD whose CLOUD AMOUNT exceeds a given value. Called ceiling... more
HEIGHT above the EARTH's surface, at a given point, of the base of the lowest CLOUD whose CLOUD AMOUNT exceeds a given value. Called ceiling in U.S. terminology.
2242
height of eye correction
See DIP CORRECTION.
2243
height of tide
The vertical distance from the CHART DATUM to the level of the water at any TIME.
2244
heliocentric parallax
See PARALLAX: ANNUAL.
2245
heliograph
A device for reflecting the SUN's RAYS from one point to another for sending messages. In METEOROLOGY, instrument which records the time int... more
A device for reflecting the SUN's RAYS from one point to another for sending messages. In METEOROLOGY, instrument which records the time interval during which solar RADIATION reaches sufficient intensity to cast distinct shadows. Also called sunshine recorder.
2246
heliostat
An instrument composed of one or more plane MIRRORS, so mounted and arranged that a BEAM of sunlight may be reflected by it in any desired d... more
An instrument composed of one or more plane MIRRORS, so mounted and arranged that a BEAM of sunlight may be reflected by it in any desired direction and kept there by continuous adjustment. It is used in geodetic SURVEYING for reflecting a BEAM of sunlight from a STATION towards another distant STATION, where it can be observed with a THEODOLITE. Also called heliotrope, or Galton's sun signal.
2247
heliotrope
See HELIOSTAT.
2248
heli pad
A site on which helicopters may land and take off.
2249
helium magnetometer
See MAGNETOMETER.
2250
Helmert spheroid
See REFERENCE SPHEROID.
2251
hemispherical map
See MAP.
2252
henry
The unit of electrical induc­tance in the SI SYSTEM.
2253
hertz
A unit of FREQUENCY in the SI SYSTEM. See also CYCLE PER SECOND.
2254
hertzian waves
See WAVE(S): RADIO.
2255
high
See ANTICYCLONE.
2256
higher high water (H.H.W)
The higher of two HIGH WATERS occurring during a TIDAL DAY if the DIURNAL INEQUALITY prevails.
2257
higher high water interval
See LUNITIDAL INTERVAL.
2258
higher low water (H.L.W)
The higher of two LOW WATERS occurring during a TIDAL DAY if DIURNAL INEQUALITY prevails.
2259
higher low water interval
See LUNITIDAL INTERVAL.
2260
highest astronomical tide
The highest tidal level which can be predicted to occur under average meteoro­logical conditions and under any combination of astro­nomical ... more
The highest tidal level which can be predicted to occur under average meteoro­logical conditions and under any combination of astro­nomical conditions.