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Eng ID Term Definition
2401
ice rise
A mass of ICE resting on ROCK and sur­rounded either by an ICE SHELF or partly by an ICE SHELF and partly by SEA. No ROCK is exposed and th... more
A mass of ICE resting on ROCK and sur­rounded either by an ICE SHELF or partly by an ICE SHELF and partly by SEA. No ROCK is exposed and there may be none above SEA LEVEL. Ice rises often have a dome-shaped surface. The largest known is about 100 km across.
2402
ice sheet
A continuous mass of ICE and SNOW of considerable thickness and large area. Ice sheets may be resting on ROCK (see INLAND ICE SHEET) or floa... more
A continuous mass of ICE and SNOW of considerable thickness and large area. Ice sheets may be resting on ROCK (see INLAND ICE SHEET) or floating (see ICE SHELF). Ice sheets of less than 40,000 sq. km resting on ROCK are called ice caps.
2403
ice shelf
A floating ICE SHEET of considerable thick­ness. Ice shelves are usually of great horizontal extent and have a level or gently undulating s... more
A floating ICE SHEET of considerable thick­ness. Ice shelves are usually of great horizontal extent and have a level or gently undulating surface. They are nourished by local snow accumulation and often also by the seaward extension of land glaciers. Limited areas may be aground. The initial stage is called BAY ICE until the surface is more than about 2 m above SEA LEVEL. The seaward edge is termed an ICE FRONT.
2404
ice storm
Intense formation of ICE on objects by the freezing, on impact, of drops of RAIN or DRIZZLE.
2405
ice wall
An ice cliff forming the seaward margin of an INLAND ICE SHEET, ICE PIEDMONT or ICE RISE. The rock basement may be at or below SEA LEVEL. Se... more
An ice cliff forming the seaward margin of an INLAND ICE SHEET, ICE PIEDMONT or ICE RISE. The rock basement may be at or below SEA LEVEL. See ICE FRONT.
2406
identification beacon
See BEACON.
2407
IEC
International Electrotechnical Commission
2408
igneous rock
ROCK formed by solidification of molten material or MAGMA.
2409
illuminated contours
An application of ILLUMINATED RELIEF in which CONTOURS appear lighter on illumina­ted SLOPES and darker on the shadow SLOPES.
2410
illuminated relief
The representation of RELIEF with the appearance of lighting from one or more directions, giving a three-dimensional impression. Also called... more
The representation of RELIEF with the appearance of lighting from one or more directions, giving a three-dimensional impression. Also called shaded relief.
2411
illumination (at a point of a surface)
Quotient of the LUMINOUS FLUX incident on an infinitesimal element of the surface containing the point under considera­ti­on, by the area ... more
Quotient of the LUMINOUS FLUX incident on an infinitesimal element of the surface containing the point under considera­ti­on, by the area of that element.
2412
image
The optical counter­part of an object.
2413
image: erect
An IMAGE that appears upright or in the same relative position as the object.
2414
image: inverted
An IMAGE that appears upside down in relation to the object.
2415
image: real
An IMAGE actually produced and capable of being shown on a surface, as in a CAMERA.
2416
image: virtual
An IMAGE that cannot be shown on a surface but is visible, as in a MIRROR.
2417
image point
In PHOTOGRAM­METRY, the IMAGE on a PHOTO­GRAPH corresponding to a definite object on the GROU­ND.
2418
imagery
Techniques to obtain, process or interpret images created by diffe­rent types of radiation, e.g. light, infrared, x-rays.
2419
impedance
The total opposition offered to an alterna­ting current. It may consist of any combination of resistance, inductive reactance, or capacitiv... more
The total opposition offered to an alterna­ting current. It may consist of any combination of resistance, inductive reactance, or capacitive reac­tance.
2420
impersonal micrometer
See MICROMETER: TRANSIT.