Geoscience Reference
In-Depth Information
Fires in Nature
CHAPTER 7
America has suffered just as badly in the past from fires,
as have Europe and the former Soviet Union. Approxi-
mately 143
INTRODUCTION
10
6
km
2
of the Earth's surface is covered
by vegetation, of which 0.17 per cent burns on average
each year. Even tropical rainforests can dry out and
burn. For example, the U Minh forest in Vietnam (see
Figure 7.2 for the location of major placenames men-
tioned in this chapter) ignited naturally in 1968. Large
fires have also burnt through tropical vegetation in the
Brazilian highlands and the Amazon Basin, especially in
association with land clearing. Many urban dwellers
would consider that, following wide-scale deforestation,
there is no forest fire threat near cities. Fires are per-
ceived to be a hazard only in virgin forest or, perhaps in
Of all natural hazards, the most insidious is drought.
However, for some countries such as Australia and
United States, droughts have not led to starvation, but
to spectacular fires as tinder-dry forests ignite, grass-
lands burn and eucalyptus bushland erupts in flame. Of
all single natural hazard events in Australia, bushfires
are the most feared. Here, the litany of disasters over
the past 150 years reads like the membership list of
some satanic cult: 'Black Thursday', 'Black Friday', and
'Ash Wednesday' (Figure 7.1). For firefighters, state
emergency personnel and victims, each name will
invoke stories of an inferno unlike any other. North
William Strutt's painting Black Thursday (LaTrobe Collection, © and with permission of the State Library of Victoria). The title refers to the
fires of 6 February 1851, which covered a quarter of the colony of Victoria, Australia.
Fig. 7.1
