Understanding global security - Peter Hough

NATURAL THREATS TO SECURITY
2 Updraught: The circulatory winds and low pressure vortex can cause large
objects and even people to be ‘sucked up’ the tornado funnel and deposited up
to several kilometres away.
3 Effect of low pressure: The extremely low air pressure in the eye of the tornado
is the most hazardous element of the phenomenon. Buildings caught in the
eye are prone to explode because of the difference in pressure inside and
outside the walls.
Floods
Floods historically are by far the biggest security threat to humanity from the nonliving
world. Although overtaken by windstorms in recent years, most of these
fatalities were also the result of flooding triggered by the effect of cyclones. Floods
often occur as secondary effects of other natural phenomena, but can present a direct
hazard to human life in a number of ways.
Flash floods occur when heavy rainfall exceeds the capacity of the ground to
absorb the water and causes a rapid, widespread deluge. Around 600 people were
killed in and around the Algerian capital Algiers in this way in 2001. Riverine floods
occur when precipitation causes a river to burst its banks. This is the most dangerous
type of flooding since it is relatively common and rivers frequently run through
densely populated areas. The Huang Ho river system in China can lay claim to being
the most hazardous natural feature on earth, having claimed millions of lives over the
centuries. Additional flooding hazards can occur when excessive inflow from rivers
or as a result of snow melt causes lakes or seas to flood.
Drowning, obviously, is the major means by which floods can kill, but this can
happen in a number of ways. People may simply be engulfed by rising waters, become
trapped in buildings or cars or in river sediment deposited by the waters. Collapsing
buildings and trees form an additional significant hazard and structural damage may
also lead to deaths by electrocution and even, with grim irony, fires. Hypothermia
and water-borne diseases are also often associated with flooding. Flooding only represents
a hazard when it is not predictable. The regular, seasonal flooding of rivers
cannot only be managed but utilized for its benefits to humankind since silt deposits
from rivers bursting their banks provide fertile soils. It is instructive that the Bengali
language has two, distinctive words for ‘flood’. Barsha refers to the usual and
beneficial floods, while the word bona is reserved for more infrequent and destructive
large floods.
Earthquakes
Earthquakes, more clearly than any natural hazard, demonstrate the centrality of the
social component in the onset of a disaster. Although the scale of seismic shocks in
the earth’s crust cannot be entirely predicted, the places where such shocks occur
is well established. Seismic activity is most pronounced on the margins of the earth’s
tectonic plates, such as along the San Andreas Fault Line, which marks the point at
which the Pacific tectonic plate meets the North American plate. The threat to
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