Changes in the Earth's Environment
The 20th century, especially in the second half, has been one of rapid
change in the Earth's environment. The impact of humans on the physical form and
functioning of the Earth have reached levels that are global in character, and
have done so at an increasingly mounting speed. 20 years ago the environment was
seen as posing a threat to the future of humanity as death rates from natural
hazards had increased dramatically since the turn of the century. The Earth
though has always been plagued by natural disasters. Now, with the world
population growing at a rapid rate more people are living in hazard prone areas.
Events which may have gone unnoticed previously, only become hazards when there
is intervention with humans and their lifestyle. With the discovery of the ozone
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
predictions of our future, most people, through media coverage, political
pressures and general concern now see the environment as being truly threatened
by human progress and in desperate need of help.
Natural hazards have been defined as “...extreme geophysical events greatly
exceeding normal human expectations in terms of their magnitude or frequency and
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,
as the nature of their impact on human populations and what they valued was
increasing in frequency at quite a rapid rate (Burton, Kates, White, 1978).
During the 75 years after 1900 the population of the earth increased by a
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
or city (Burton et al,1978.). It is this growing world population, Burton et al
(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
number of disasters remained relatively constant at about 30 per year, death
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...