W
A disruption of the airflow behind a moving aircraft that produces turbulence.
Deep east-west air circulation caused by the contrast between the warm waters of the western Pacific and the cooler waters of the eastern Pacific.
The horizontal movement of warmer air into a location.
Leading edge of a relatively warm air mass moving into a region of cooler air.
Section 125 of the Water Act 2007 defines water information as:
(a) any raw data, or any value added information product, that relates to:
(i) the availability, distribution, quantity, quality, use, trading or cost of water; or
(ii) water access rights, water delivery rights or irrigation rights; or
(b) any metadata relating to data of a kind referred to in paragraph (a);
and includes contextual information relating to water (such as land use information, geological information and ecological information).
An area (however described) used by an agency of the Commonwealth or an agency of a State for the purposes of managing surface water or ground water.
Examples of water management areas:
- river basins
- catchments
- aquifers
- water sources
- sustainable diversion limit resource units.
A body of water that is naturally occurring, is impounded by a constructed barrier or is within an excavation, and includes ponds, swamps, lakes, wetlands, weirs, dams, basins, reservoirs and open pits.
Water in its gaseous form.
Atmospheric pressure caused by water vapour. This is one way of measuring humidity. At a given temperature, an increase of water vapour in the air corresponds to an increase in humidity.
The depth of water that would result if solid precipitation were melted.
Height difference between the wave crest and the preceding trough.
Average horizontal distance between successive crests (or troughs) of a wave pattern.
Average time between successive crests (or troughs) of waves.
Index to measure thermal stress – or how comfortable you might feel under certain atmospheric conditions. It takes into account wind, air temperature, humidity, and radiation from the sun and nearby hot surfaces.
Annual season in the tropics that is warm, humid and wet. In northern Australia, it's from October to April. In some parts of our tropics, such as Western Australia, the wet months are only from about January to March.
Temperature measured using a thermometer with the bulb wrapped in wet muslin. The evaporation of water from the thermometer has a cooling effect, so the temperature is less than that measured by a dry-bulb (unmodified) thermometer.
A small-scale, rapidly rotating column of wind, formed thermally and thus most likely to develop on clear, dry and hot afternoons. Often called a dust devil when made visible by the dust, dirt or debris it picks up. In aviation forecasts and reports it is coded as PO.
Occurs when clouds and the earth’s surface seem to blend, resulting in the horizon becoming erased.
Moving air in a continuous succession of gusts, lulls and changes of direction.
The product of the average wind speed and the period over which that average speed was measured.
Wind direction and/or speed change over a vertical or horizontal distance.
Speed at which wind is blowing.
Our measured wind speeds are generally averaged over 10 minutes at a standard height of 10 m above open, flat ground or sea.
The 10-minute average wind speed is also what we forecast.
Wind speed is given in kilometres an hour in land areas and knots in marine areas.
Wind gusts are stronger than average wind speeds.
Waves generated by the current (and recent past) wind in the area. Also called sea waves.
Measure of the cooling effect of the wind on body temperature.
Prolonged period of average wind speeds exceeding 40 km/h during the day.
One of the 4 seasons of the year. In the southern hemisphere it's the 3 coldest months – June, July and August.