DMSPDefense meteorological satellite program.
DOWNWINDThe direction towards which the wind
is blowing; with the wind.
DROPSONDEA radiosonde instrument dropped by
parachute from an aircraft.
DSNDefense switched network, an upgrade and
name change to the automatic voice network
DUCTA layer in the atmosphere that readily traps
electromagnetic energy permitting extended
DUCTINGThe process occurring within a duct, also
known as trapping.
EDDEffective downwind direction (radioactive
EDFEffective downwind forecast.
EDMEffective downwind message (radioactive
FAAFederal aviation administration.
FATHOMETERA device used to measure the
depth of the ocean.
Oceanography Center, Monterey, California.
FRONTThe interface or transition zone between two
air masses of different density. Since temperature
is the most important regulator of atmospheric
density, a front almost invariably separates air
masses of different temperature.
GEOPHYSICS Used to mean working with the
physical properties of both the air, land, and water,
this term is occasionally used to describe the
occupational field of Navy and Marine Corps
GEOPOTENTIAL HEIGHTThe height of a given
point in the atmosphere calculated with respect to
the energy in the column of air beneath the point,
relative to sea level. In other words, an
approximation of the height based on measured
temperatures, pressures, and humidity content of
the supporting air column, and not necessarily an
exact measured height.
GFMPLGeophysics fleet mission program library.
GHzGigahertz, (1 billion hertz)
GMTGreenwich mean time, a term replaced by
coordinated universal time (UTC).
GPMGeopotential meters, also gallons per minute.
GZ round zero, the detonation point of a weapon,
HDOHorizontal distance out (when evaluating
upper winds); or hurricane duty officer.
HECTOPASCAL (hPa)A unit of 100 pascals used
to measure pressure, exactly equivalent to 1
ICAOAbbreviation for international civil aviation
IFRAbbreviation for instrument flight rules.
INFRARED (JR)The portion of the electromagnetic
spectrum with wavelengths just slightly longer than
visible light energy-thermal energy.
INVERSIONWith respect to temperature, an
increase in temperature with height. Normally
temperature decreases with height in the
IRCSInternational radio call sign.
IREPSIntegrated refractive effects prediction
KHzKilohertz; 1,000 hertz or cycles per second.
KILOTON(KT) A multiplication factor for nuclear
weapon yields. Each kiloton is equal to the
explosive force of 1,000 tons of trinitrotoluene