Ice cores
Core sample from the accumulation of snow and ice over many years that have re-crystallized, trapping air bubbles from previous time periods.
- See:
- Core sample
Ice crystal model
- See:
- Bergeron process
Ice crystals
Macroscopic crystalline form of ice, which has the shape of hexagonal columns and plates, dendritic crystals, needles and their combinations. They form at very low temperature (0°F/-18°C or less) in stable atmosphere.
Ice pellets
Type of precipitation consisting of transparent or translucent particles of ice, of 5 mm or less in diameter. Their form may be spherical, irregular or eventually conical. They include two basic types: sleet and small hail.
Ice storm
Strom characterized by the fell liquid precipitation that freezes on impact on terrestrial objects, creating a coat of glaze on them.
Icon
Sign which refers to the object that it represents by virtue of characteristics of its own. Recognizable image of the object that the sign represents.
Influenza
Acute contagious viral infection characterized by inflammation of the respiratory tract, with fever, muscle pain, chills. It can be less severe, but it always brings fever and respiratory involvement.
Infrared radiation
Portion of the electromagnetic spectrum between visible light and microwaves, that is between 0.75 and 1000 µm.
Intertropical convergence zone / ITCZ, Equatorial convergence zone
Narrow zone where the southeast trades (of the Southern Hemisphere) and the northeast trades (of the Northern Hemisphere) meet.
Intertropical front / Equatorial front, tropical front 
Quasi-permanent front that exists within the equatorial trough, separating the Northern and Southern Hemispheric trade winds or marking the extreme limit of a tropical monsoon.
Ionosphere
Atmospheric region, located in the upper mesosphere and good part of the thermosphere, which contains significant concentrations of ions and electrons in sufficient quantities to reflect electromagnetic waves.
Irisation or iridescence
Colors appearing on clouds, sometimes mingled, sometimes in the form of bands nearly parallel to the edges of the clouds. Green and pink predominate, often with pastel shades. The cause is sunlight being diffracted by cloud particles