Environmental Engineering Reference
In-Depth Information
nineteenth century, for example, gave rise to the
concept of the Great American Desert.
Although the concept has been criticized for
being as much myth as reality, it is now evident
that several expeditions to the western United
States in the early part of the century (Lawson
and Stockton 1981), and some decades later to
western Canada (Spry 1963), encountered
drought conditions which are now known to be
quite typical of the area, and which have been
repeated again and again since that time.
(1971) has estimated that fully half the settlers
in Nebraska and Kansas left the area at that time,
like the earlier inhabitants, seeking relief in
migration, in this case back to the more humid
east. Some of those who stayed experimented
with dry-farming, but even that requires a
modicum of moisture if it is to be successful.
Others allowed the land to revert to its natural
state, and used it as grazing for cattle, a use for
which it was much more suited in the first place.
The lessons of the drought had not been learned
well, however. Later, in the 1920s, the rains
seemed to have returned to stay and a new
generation of arable farmers moved in. Lured by
high wheat prices, they turned most of the plains
over to the plough, seemingly unconcerned about
the previous drought (Watson 1963). Crops were
good, as long as precipitation remained above
normal. By 1931, however, the good years were
all but over, and the drought of the 1930s, in
combination with the Depression, created such
disruption of the agricultural and social fabric
of the region that the effects have reverberated
down through the decades. Even today, every dry
spell is compared to the benchmark of the
Dustbowl. The only possible response for many
of the drought victims of the 1930s was
migration, as it had been in the past. The Okies
of
The Grapes of Wrath,
leaving behind their
parched farms, had much in common with the
Indians who had experienced the Pueblo drought
six centuries before. The societies were quite
different, but they felt the same pressures, and
responded in much the same way. By migrating,
both were making the ultimate adjustment to a
hostile environment.
If the drought of the 1930s brought with it
hardship and misery, it also produced, finally, the
realization that drought on the plains is an
integral part of the climate of the area. Intense
dry spells have recurred since then—particularly
in the mid 1970s and early 1980s (Phillips 1982)
and again in 1987 and 1988—causing significant
disruption at the individual farm and local level.
Because of the general acceptance of the
limitations imposed by aridity, however, the
overall impact was less than it would have been
Historical drought
Local drought is not uncommon on the plains.
Almost every year in the Canadian west there
are areas which experience the limited
precipitation and high temperatures necessary for
increased aridity (McKay
et al.
1967), and
archaeological evidence suggests that from the
earliest human habitation of the plains it has been
so (Van Royen 1937). The original inhabitants,
who were nomadic hunters, probably responded
in much the same way as the people of the Sahel,
when drought threatened. They migrated,
following the animals to moister areas. At times,
even migration was not enough. For example,
during the particularly intense Pueblo drought
of the thirteenth century, the population was
much reduced by famine (Fritts 1965). Major
drought episodes, extensive in both time and
place, are also a recurring feature of the historical
climatology of the Great Plains (Bark 1978;
Kemp 1982), with the groups of years centred
on 1756, 1820 and 1862 being particularly
noteworthy (Meko 1992).
The weather was wetter than normal when
the first European agricultural settlers moved into
the west in the late 1860s following the Civil War.
The image of the Great American Desert had
paled, and the settlers farmed just as they had
done east of the Mississippi or in the mid-west,
ploughing up the prairie to plant wheat or corn.
By the 1880s and 1890s, the moist spell had come
to an end, and drought once more ravaged the
land (Smith 1920), ruining many settlers and
forcing them to abandon their farms. Ludlum
