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The terms and definitions found in the glossary relate to the science of meteorology.
For descriptions and definitions of words used in the Bureau's forecasts and warnings, please refer to Weather Words.
- Indigenous Weather
- Indigenous Australians have long held their own seasonal calendars based on the local sequence of natural events.
For further information see Indigenous Weather Knowledge - Inshore
- The coastal waters zone within 12 nautical miles of the coast.
- Inversion, temperature
- A temperature inversion occurs when the temperature of air increases with increasing height. Generally the temperature decreases with height in the lower atmosphere, called the troposphere. Low-level inversions generally form on clear calm nights due to cooling of the ground through loss of heat by radiation. The warm air on the ground is replaced by cooler air at the surface resulting in a temperature inversion. The inversion creates a boundary layer that restricts vertical motion and mixing of air between the two air masses either side. Low-level inversions act like a lid to trap pollutants resulting in smog over our cities.
For further information please read http://www.bom.gov.au/info/ftweather/page_16.shtml - ISA
- International Standard Atmosphere (ISA) is the 'average' atmosphere any pressure level has a standard corresponding altitude called 'pressure altitude' and temperature called the 'ISA temperature'.
- Isobars
- Lines on weather maps joining places which have the same air pressure.