Environmental Engineering Reference
In-Depth Information
weather
The current or short-term state of the
atmosphere
expressed in terms of such variables
as temperature, precipitation, airflow and
cloudiness.
weather forecasting models
Models which use
fundamental equations representing atmospheric
process to predict short-term changes in
meteorological elements.
weather modification
Any change in weather
conditions caused by human activity, whether by
design or accident.
weathering
The physical and chemical breakdown of
rocks at the earth's surface, brought about by
exposure to air, water, temperature change and
organic activity.
wet deposition
The most common form of
acid
precipitation,
in which the acids are present in
solution in the atmosphere and reach the earth's
surface in rain, snow, hail and fog. (See also
dry
deposition
.)
windbreak
A row of trees or shrubs planted at right
angles to the airflow. The consequent reduction in
windspeed helps to protect sensitive plants, reduces
the rate of
evapotranspiration
and helps to prevent
soil erosion
.
World Commission on Environment and Development
A commission chaired by Gro Harlem Brundtland,
the Norwegian Prime Minister, in 1987. It
promoted the concept of
sustainable development,
and led directly to the
UNCED
.
World Meteorological Organization (WMO)
A United
Nations sponsored organization based in Geneva,
Switzerland, which coordinates worldwide,
weather data collection and analysis.
X, Y, Z
xerophytic vegetation
Plants adapted to life in arid
conditions.
zonal index
A measure of the intensity of the
midlatitude atmospheric circulation pattern.
During a period of high zonal index, the airflow is
west to east or latitudinal. A low zonal index
involves a south-north-south or meridional
component as a result of waves forming in the
airflow.
