Global Environmental
Issues
Ozone Depletion &
The Collapse of Fisheries
11/19/08
Ozone depletion and the collapse of
fisheries are or at least should be of global concern. The depletion and collapse are attributed to
global manufacturing, production, and consumption. Social, political, environmental, and
economic issues have direct and indirect influences on the Earth we live on and
the species that inhabit it. In this
paper we will discuss global environmental issues with an emphasis on ozone
depletion and the collapse of fisheries.
Ozone Depletion
The ozone is composed of a thin
layer of the oxygen that is poisonous in its natural state. The ozone is in essence an oxidizer that can
be harmful to living creatures and many materials. This ozone gas occurs
naturally in clean air but in harmless amounts only ten parts per billion
(ppb). “This term was coined in 1839 by
Christian Friedrich Schonbein (1799-1868), a chemistry professor at the University
of Basel, Switzerland, who noticed a peculiar Gestank while running electrical
currents through water. In German he said Ozon , which is derived from the
Greek o’zein, meaning to smell” (Biddle, 1998).
The smell Friedrich smelled is
similar to what one may smell in the air after a thunderstorm. It comes about
because ordinary oxygen molecules are dissociated by lightning bolts. These
free atoms combine with other 02 molecules and form the triatomic ozone. This
form of oxygen is highly unstable because it will give the extra 02 molecule to
any substance it comes in contact with in a effort to become 02 once again.
Ozone is located ten to fifty kilometers above the earth’s surface on the
stratosphere it plays an important role in promoting and protecting human,
animal and environmental life; by preventing the sun’s ultraviolet B radiation
from reaching the earth’s surface. In its naturally occurring state it could
prevent up to 99% if this UV radiation from reaching the earth’s surface.
The
chemical compound culprit behind the exacerbated depletion of the ozone is
known as chlorofluorocarbons. These are a class of synthetic organic chemical
compounds composed of carbon and various combinations of chlorine, fluorine,
and hydrogen. These chemical compounds are better known as CFCs and are non-toxic
and stable once released primarily. CFCs were developed in 1928 for use in home
refrigeration units, replacing less stable, (flammable), compounds that were
harder to implement into the manufacturing process. There uses grew rapidly
during the 1950’s and this trend continued through the mid 1970’s. CFCs were
implemented in a wide range of applications such as cleaning and blowing
agents, and propellants.
CFCs
stability is what makes them so harmful to ozone layer and thus human and
organic life. CFCs drift into the
stratosphere before decomposing. “As hypothesized in 1974 by F. Sherwood
Rowland and Mario Molina (who won a Nobel Prize in 1995 for their work),
chlorine from CFCs is able to break down ozone in the stratosphere. CFCs and
other ozone-depleting substances, in the presence of ultraviolet radiation,
eventually decompose to include a chlorine free radical, which reacts with
ozone to create an oxygen molecule and chlorine monoxide. The chlorine molecule
can repeat the process, causing a chain reaction in which one chlorine atom can
destroy thousands of ozone molecules.” …
