ACCRETIONGrowth or increase in size by gradual
AGLAbove ground level. Measurements suffixed by
the abbreviation AGL refer to height.
measurement for a substance under surrounding
AMDARAircraft meteorological data relay.
analogue recorder draws continuous lines
proportional to the electronic signal input. In an
analogue signal, the sound pitch varies
proportionately with the intensity of the signal, and
the signal is continuous.
ANEMOMETERA device used to measure wind
speed and/or wind direction. From the Greek word
anemo, meaning wind, and modern word meter,
meaning measurement device.
ANEROIDWithout fluid or without water. An
aneroid barometer uses no fluid (mercury).
APPARENTThe way something appears or is
perceived, although it may not be true.
ASCENSION Rising or increasing in elevation.
ASOSAutomated surface observing system.
AUTODIN Automatic digital network.
AWNAutomated weather network-the complex
worldwide collection and distribution network of
meteorological data and NOTAMs operated by the
Air Force for the DoD.
AZIMUTHThe horizontal angular measurement
from a fixed reference to a point. The Navy uses
angular measurements in clockwise degrees from 0
to 360. When 0 is referenced to true north, the result
is a true azimuth bearing. When referenced to an
arbitrary direction. such as the bow of a ship. the
result is a relative azimuth bearing.
BACKINGA change in wind direction in a counter-
clockwise manner in the Northern Hemisphere, or a
clockwise direction in the Souther Hemisphere.
BATHYTHERMOGRAPHAny device used to
measure and record temperatures through a column
CAD Collective address designator.
CDDChemical downwind direction.
CDSChemical downwind speed.
CENTIGRAYS (cGy) A measurement of absorbed
radiation equal to 1 rad.
CICCombat information center aboard ship.
CLIMATICAny element associated with the
climate of an area.
CLIMATOLOGY The study of the statistical
means, frequencies, deviations, and trends of
weather elements for an area over a period of time.
CODARCoded aircraft report.
DDNDefense data network.
DHDDownwind hazard distance (radiation or
DIURNALAny change that follows a daily pattern.
completing one cycle on a daily basis.
DMEDistance measuring equipment, a radio aircraft
navigation aid that provides only a distance to a
DME transmitter site. Normally used in
conjunction with VOR, ILS, or LOC equipment.
DMSPosition given in degrees. minutes, and seconds
of latitude and longitude.