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Hurricanes: Science and Society
Glossary - I
I
indirect hit
Generally refers to locations that do not experience a direct hit from a tropical cyclone, but do experience hurricane force winds (either sustained or gusts) or tides of at least 1.2 meters (4 feet) above normal. Source NOAA-NHC.
indirect measurements
A process where the measurement of some entity is not obtained by the direct reading of a measuring tool, or by counting of units superimposed alongside or on that entity. For example if the length and width of a rectangle are multiplied to find the area of that rectangle, then the area is an indirect measurement.
intensification
The strengthening of a hurricane causing it to become more extreme.
intensity
The strength of a hurricane, usually described by the wind speed. Intensity is often given as a number from the Saffir-Simpson Hurricane Wind Scale.
Intertropical Convergence Zone (ITCZ)
The region where the northeasterly and southeasterly trade winds converge, forming an often continuous band of clouds or thunderstorms near the equator. Source: NOAA-NWS ERH
inundation
The process of covering normally dry areas with flood waters.Source: NOAA-NWS
invest
A weather system for which a tropical cyclone forecast center (NHC, CPHC, or JTWC) is interested in collecting specialized data sets (e.g., microwave imagery) and/or running model guidance. Once a system has been designated as an invest, data collection and processing is initiated on a number of government and academic web sites, including the Naval Research Laboratory (NRL) and the University of Wisconsin Cooperative Institute for Meteorological Satellite Studies (UW-CIMSS). The designation of a system as an invest does not correspond to any particular likelihood of development of the system into a tropical cyclone; operational products such as the Tropical Weather Outlook or the JTWC/TCFA should be consulted for this purpose. Source NOAA-NHC.
island breaching
During the period of inundation, currents and waves carry large volumes of sand from the seaward to the landward side of the island. When water levels subside, currents may reverse direction carrying sediment from sounds and bays back to the open ocean. These strong currents may carve a channel in the island, causing the island to be bisected in a process known as island breaching. Source: USGS