Environmental Engineering Reference
In-Depth Information
supernova
A star which over a short period of a few
days becomes exceptionally bright, and emits high
levels of cosmic radiation, before declining again.
supersonic transports (SSTs)
Commercial aircraft that
routinely fly faster than the speed of sound, and at
higher altitudes than subsonic airliners. Flying high
in the
stratosphere,
they inject ozone destroying
pollutants such as
oxides of nitrogen
and
odd
hydrogens
directly into the
ozone
layer.
sustainable development
Development which is both
economically and environmentally sound, so that
the needs of the world's current population can be
met without jeopardizing those of future
generations.
Sustainable Development Commission
An institution
established as a result of the
Earth Summit,
aimed
at monitoring and promoting the approach
towards
sustainable development
identified at the
Summit.
system
An assemblage of interrelated objects organized
as an integrated whole. The earth/atmosphere
system, for example, includes the various physical
and biological components of the environment.
These components are closely interrelated and work
together for the benefit of all.
as the Blue Mountains of Virginia in the United
States.
terrestrial environment
That part of the environment
that includes the components of the land surface—
such as rock and soil—and the plants and animals
that live on it.
terrestrial radiation
Low energy,
long-wave radiation,
from the
infrared
sector of the spectrum, emitted
by the earth's surface.
thermal low
Low pressure system produced by the
heating of the earth's surface and the air
immediately above it. The process is particularly
effective in areas of high
insolation
.
thermonuclear device
A powerful bomb in which the
explosive force is created by the fusion
(combination) of the nuclei of hydrogen atoms—
hence the name 'hydrogen bomb'.
thermosphere
The outermost layer of the atmosphere
beyond the
mesopause
some 80 km above the
earth's surface.
Third World
A term commonly applied to the
developing and non-aligned nations of Africa, Asia
and Latin America, to distinguish them from the
'western' nations of the 'first world' with their
developed, capitalist economies, and the
communist nations of the 'second world' with their
centrally-planned economies.
30 per cent club
A group of 21 nations—mainly from
Europe, but including Canada—which agreed in
1985 to reduce trans-boundary emissions of
sulphur dioxide by 30 per cent (of the 1980 level)
by 1993, in an attempt to deal with the growing
problem of
acid rain
.
topsoil
The uppermost layer of the soil containing the
bulk of its organic material, nutrients and living
organisms.
tornado
An intense rotating storm usually no more
than 100 to 500 m in diameter, originating where
cold and warm, moist air masses collide, and
accompanied by winds that commonly exceed 200
kph.
transient models
General circulation models
which
attempt to provide information at intermediate
stages during the model run, unlike
equilibrium
models
which provide only one final result.
transpiration
The loss of water from vegetation to the
atmosphere by its
evaporation
through leaf pores
in individual plants.
tree dieback
The gradual wasting of a tree from the
T
tall stacks policy
An approach to the problem of local
air
pollution,
which involved the building of tall
smokestacks to allow the release of pollutants
outside the local atmospheric boundary layer. While
this reduced local pollution, it introduced
pollutants into the larger scale circulation and
contributed to the
long range transportation of air
pollution (LRTAP)
.
teleconnection
The linking of environmental events
in time and place. The linkages usually involve a
time-lag and include locations that may be
wellseparated from each other. For example, an
El
Niño
in the eastern Pacific late in one year may be
linked to the failure of the Indian monsoon in the
following year.
temperature inversion
The reversal of the normal
temperature decline with altitude in the
troposphere
. In an inversion, the temperature rises
with altitude because of the presence of a layer of
warm air above the cooler surface air.
terpene
One of a group of
hydrocarbons
found in the
essential oils of some plants, particularly conifers.
Released from these plants, terpenes may be
responsible for the haze common over such areas
