- Migrated to GDrive
Ice Age—use initial caps for the most recent glacial period, lower case for all other references (American Heritage Dictionary, Third Edition). [revised 2/00]
i.e.—stands for "id est" (that is); not italicized, and always set off by commas
imagery, satellite—see satellite-based imagery
initials, two or more—no space between them in individuals' names: T.N. Krishnamurti. See also "names."
in situ—not italicized, no hyphen as modifier; means "in (a fixed) position," i.e., neither mobile nor flying aboard aircraft or satellite.
I/O—input/output (computer term)
instrument names—use initial caps for instruments and instrument systems: Limb Radiance Inversion Radiometer (LRIR), Advanced Coronal Observing System, S-Band Dual Polarization Doppler Radar (S-Pol), but S-Pol radar.
ionization states—(series) are given by capital Roman numerals—Fe XI, Ba II, etc. Use a space (not a hyphen) between the element abbreviation and roman numeral. See complete list of chemical elements in The Chicago Manual of Style.
Iris giclée—Iris is a brand name, giclée is a coined term for a fine art or archival inkjet print.
isotope numbers—in outreach materials, write this way: The isotope carbon 13 (C-13) [spellout is open, abbreviation takes a hyphen]. For scientific/technical material: to abbreviate, put the number before the element: 13C, 90Sr, etc.