Evening star., 1901-09-07
NATURES REVENGE
That's What Farmer" Dunn Calls a
Hot Wave.
GREAT HEAT FOLLOWS IRRIGATION
Moisture From bitches Forms Low
Pressure Areas.
THEN TROUBLE BEGINS
GREAT HEAT FOLLOWS IRRIGATION
THEN TROUBLE BEGINS
Copyright, 1901

Copyright, 1901
Written for The Evening Star by f. B. Dunn.
There has recently afflicted the states west
of the Mississippi river a heated SPELL
which for suffering inflicted on human be-
ings and for damage done to stock and
crops, is, perhaps, ,unexcelled in the weather
records. For period of several weeks tenn
peratures ranging in the neighborhoOd or
100 degrees have burnt the life out Of vege-
tation, that the full extent of the loss
will not be known for long time yet
Visitation of Providence" Is the phrase by
which such a calamity is usually described,
but a careful consideration of the circum-
stances indicates rather that the late de-
structive hot wave is the result of mans
own devices; that the work of years where
by he has sought to turn the land to his own
purposes is now bringing about an unex-
pected and alarming result. In short, there
is sound reason for believing that where
man has altered the landscape nature has
followed by changing the weather.
1t has been advanced by one of the lead
ing papers of Colorado in suggesting an in
creased appropriation from Congress for the
extension Of the system of artificial lrriga-
ton in the states west of the Mississippi
river that the great heat waves visiting that
section modified by the irrigation sys-
TEN, and further extension of these water
ways would have an effect In preventing or
disSipating the intense heat and be the
means of saving crops in the future. While
this statement may appear to have the right
ring and show that the cause for the loss of
crops in that section had been discovered
and point out way to remedy the evil by
an appropriation from Congress, there is
another side to the question. Has not irri-
cation brought into existence the very evils
which its advocates claim that 1t has de-
StrOyed? Is not nature, whose waste and
arid places have been watered by mans ar
tfice, scourging the land with fiery punish
ment in revenge for that interference with
her plans? There is certainly ground enough
for belief in this theory to give pause before
assume broadly that irrigation is miti-
giant of blighting heat and Il savior instead
OF an incendiary of crops.
The Blessed Water.
Certain parts of the country have, in the
geologic development of the earth through
thousands of centuries, become almost
drained of moisture. In all other respects
the soil is admirably suited to mans pur-
poses farming or stock raising. If the set
tier can bring water thither. the wilderness
will blossom into riches for him. So he sets
about tapping streams, scores or even nun
dreds Of miles away, and presently the dry
soil is drinking IN moisture from long lines
of bitches. New vegetation springs up; cat
tie spread abroad over the ranges; land that
was worth no mans attention assumes
value. and settlers begin TO flock to the
region. From the point of view of the earth
on which we live the results are highly
satisfactory.
But the atmosphere which surrounds
the earth and of the mysterious and
often terrific working of which we know
so little, is highly volatile and sensitive
element. Changes in the earth's surface
may have far-reaching effects upon the
surrounding air. II a great body OF water
were suddenly introduced into a region
which before had been desert, such as
was suggested in the induction of the
ocean into the Sahara, there IS no doubt
but that tremendous and permanent at
mospkeric alterations would result. Sim
ilarly it is reasonable to suppose that the
irrigation of a great tract of land in the
west will have been accompanied by al
tcration in weather conditions. not only
local. but widespread in influence. And
here is a significant fact bearing upon this
question.
What Science Proved.
In 1880, when / made a careful investi-
CATION for the Scientific Academy of New
York of the theory that our climate was
changing in consequence OF shifting of
the gulf stream. l found the alteration
Of weather conditions was much greater
in the central west and In that part of
the country just east of the Rocky noun
tains than along the Atlantic coast. Fur
thermore il developed that many low
pressure storms originated in the great
plateau of the Rocky mountains: that
Scme moved slowly northeastward, while
others fingered with little or no energy
until the whole central mountain system
would be enVeloped in an oblong baro-
metric depression extending over several
states and into the upper Missouri val
ley. Often these depressionS were df-
vided by areas of high pressure forming
two distinct low pressure centers of what
sort of barometric trough. Dur
ing the existence OF these low pressure
h. afNrra tA nr,H
south of them was above the normal.
Many low pressure areas passing inland
from the north Pacific were drawn out of
their natural course southward into the
states east of the Rocky mountains, as
shown by charts OF storm tracks of the
weather bureau. Some reason for this must
exist. To all appearances the reason was
artificial irrigation.
heat wave that has burned up the corn and
other crops in the middle west came about.
In the irrigation region of southeast Mon-
tana. northern Wyoming and Nebraska an
area of low pressure was formed. Storms
or atmospheric depressions move across any
section where they are nourished by mois-
rure. but during the warm months they
may linger for weeks over some section
where they do not gather enough moisture
to give them motive energy. That is what
seems TO have happened in this case. A
system OF irrigation continued for years in
that part OF the country has now extended
over millions OF acres, affording enough
evaporation to call the low pressure into
existence. but not enough energy to set 1t
In motion.
Cause and Effect.
low pressure area Is a sort of vacuum
into which pour currents Of air from all
sides. The areas of low pressure contering
over the eastern Rocky mountain slope and
stretching into the upper Missouri valley
control the direction of the winds for the
entire region between the Mississippi and
the Rockies and from Montana to Texas,
the general surface direction being toward
the center of atmospheric depression. The
last great heat wave held its position vary
ing from Utah northeast to South Dakota.