Changes in the Earth’s Environment
The 20th century, especially in the second half, has been one of rapid
have done so at an increasingly mounting speed. 20 years ago the environment was
hazards had increased dramatically since the turn of the century. The Earth
though has always been plagued by natural disasters. Now, with the world
Events which may have gone unnoticed previously, only become hazards when there
hole in the 1980’s attention was now more focused on the threat humans were
posing to the environment. With scientific evidence to back up pessimistic
pressures and general concern now see the environment as being truly threatened
Natural hazards have been defined as ?…extreme geophysical events greatly
causing significant damage to man and his works with possible loss of life.?
(Heathcote,1979,p.3.). A natural hazard occurs when there is an interaction
between a system of human resource management and extreme or rare natural
phenomena (Chapman,1994). As McCall, Laming and Scott (1991) argue, strictly
speaking there is no hazard unless humans are affected in some way. Yet the line
between natural and human-made hazards is a finely drawn one and usually
overlapping. Doornkamp ( cited in McCall et al, 1992) argues that many hazards
are human induced or at least made worse by the intervention of humans.
In the 1970’s, natural hazards were an important subject of topical study,
increasing in frequency at quite a rapid rate (Burton, Kates, White, 1978).
staggering 2.25 billion people. People who needed land on which to live and work.
As the population rose people were dispersed in more places and in larger
numbers than before. The predominant movement of people being from farm to town
(1978) suggest, that is the main reason behind why hazards are increasing and
were seen to pose such a threat to humankind in the 70’s. While the average
rates climbed significantly.
As the growing world population requires the cultivation of land more prone
to hazards, more people and property are thus exposed to the risk of disaster
than ever before, and as Stow (1992) argues, the death toll inevitably rises. An
example that shows the concern that humans faced from the environment can be
250,000 people. Although part of the reason for so many deaths can be put down
a rising population, land in Bangladesh was reclaimed by the government and held
against the sea. People in large numbers were then encouraged to occupy the area.
An area which turned out to be one of great risk. Major disruption was
inevitable Burton et al (1978) argue whenever population was in the path of such
forces. Had reasonable measures been taken in advance of the storm, the material
damage, loss of life and social dislocation could have been seriously reduced.
monitoring and predictive capabilities for natural hazards. The use of advanced
telecommunications and emergency management, together with the exploitation of
extent to which natural hazards are seen as a threat to people in the 90’s
(Chapman et al, 1994). Loss of life and property from natural disasters
continue to rise though as the population of the world rises and puts more
demands on the environment for land resources. White (1974) argues that
environmental risk may be considered to be primarily a function of the value
systems of a society. How dangerous a natural hazard is, is not measured in
absolute terms but in how dangerous it is perceived to be. 20 years ago,
technology hadn’t advanced to the level at which natural hazards could be
properly understood and prepared for (Perry,1981). Chapman (1994) argues that in
technologically advanced societies we have ?…greatly accepted the hazards
inherent in the comforts of life that technology provides and learned to live
?normal human expectations? were lower than they are today therefore causing
such concern for the environmental threat to humans.
20 years ago it was the spectacular, rapid onset, intensive hazards such as
caused concern for the future of humankind from the environment. Today it is the
slow onset, pervasive hazards that have caught the attention of the whole world,
and in the long term pose more threat than the intensive hazards (Chapman,1994).
contributing to this long term threat and the future of the planet as a whole
environmentalism will be judged to be the single most important social movement
of the period (Brenton,1994). While the threat from humans to the environment
diversity and the destruction of the rainforests. Prior to the late 20th century
the main insults to the environment were evident, people could see smog and
a new type of danger to the environment (Suzuki,1990). Dangers which are much
less visible and often will not materialise for years to come. It is primarily
because of scientific predictions that we know about them and without science
would have probably gone largely unrecognised until it was too late for action
to be taken (McKibben,1989). These new dangers are ones that can be measured and
and is being damaged more rapidly than ever before is a far more prevalent and
respectable belief than ever before. It is a belief that is growing in
?… increasingly the assumption that the earth is being
improved requires a defence and an explanation, while
the assumption that it is being dangerously degraded
requires none.? (p.304).
most pressing problems.
Perhaps the most powerful representative of this new ?global consciousness’
has been as Brenton (1994) suggests, the ?Earthrise’ photograph taken by the
time, they are also able to see more clearly that which ecologists have always
stated, that everything on the earth is tied to everything else (Pearce,1995).
Since it’s capture , the ?earthrise’ photograph has been extensively exploited
by exponents of the ?fragile planet’ view of the human experience. Between 1970
and 1990 global population rose from 3.7 billion to approximately 5.3 billion
people. Energy consumption grew even faster, while nuclear production of
electricity rose twentyfold. The number of vehicles more than doubled and by the
early 1990’s people were consuming about 40% of the entire global ?natural
have been devastated and the productivity of more than 1.2 million hectares of
been put there by humans, largely through C.F.C production, and it has been
C.F.C’s that have created one of the most disturbing changes to the environment,
existence is essential for many life supporting systems. Ozone occurs at two
levels in the atmosphere; the stratosphere and the troposphere. In the
stratosphere it is concentrated into the ?ozone layer’, and it is this
concentration that protects the earth from U.V radiation from the sun, taking
out 90% of U.V rays. It’s depletion was first recognised in 1985, when a gaping
hole was found over Antarctica. By 1989 it became clear that C.F.C’s and halons
were indisputably implicated in the collapse over Antarctica, that ozone had
diminished over heavily populated areas of the world and that further
significant depletion would occur if extreme action was not taken to stop ozone-
depleting substances (Kevies,1992).
Apprehension of global warming on the other hand, rests on the theory that
high concentrations of CO2 in the atmosphere trap radiation reflected from the
earth, creating a ?greenhouse effect’. This then leads to an increase in
given to the climatic impacts of CO2 owes much to the weather of the 1980’s
(Schnieder,1989). The 80’s were already the warmest on record, when the hot
spring and summer of 1988 came along, bringing with it drought, crop disasters
warming in 15 weeks than anyone else was able to do for the previous 15 years.
How much of this warming is due to an increase in CO2 though and what the actual
consequences will be is a debatable subject (Pearce,1995). Although climatic
change is occuring, why it’s occuring is not known for certain. Pearce (1995)
argues though, that even if the science of global warming turns out to be
incorrect, it is not worth the risk to do nothing about it. McKibben (1990)
declares that to doubt that the warming will happen because it hasn’t yet
appeared is?… like arguing that a woman hasn’t yet given birth and therefore
isn’t pregnant.? (p.12).
As the 20th century draws to a close, a general awareness is spreading
around the globe that human activity can and is causing serious damage to the
environment. Slogans such as ?think locally,act globally’ and ?the earth is one
but the world is not’ adhere to the principal that, everything is tied to
everything else. Problems on land become problems at sea and in the environment.
Humans now realise that it is they that pose the threat to the environment,
rather than the environment being a threat to humanity. The danger is shining
through the sky, with overwhelming evidence that the earths ozone layer is being
destroyed by human-made chemicals far faster than any scientist had predicted.
The threat is no longer just to the future, the threat is here and now.
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