Deseret evening news. [volume] (Great Salt Lake City [Utah]) 1867-1920, 1908-07-04
Brief Notes on Its Physical Fea-
lures. Resources. and Development.
UTAH
! MOUNTAIN WINDS oYcLoNIc WAVES AND CLIMATIC CHANGES

The amount of Our mountain rainfall
has not vet been determined; 1t varies
with locality and altitude, and prob
ably does not exceed 25 inches IN q
year. That of the valleys varies from
to 6 inches Just east of the Sierra
Nevadas and south OF the Great Basin
TO from 60 16 inches elsewhere. In the
valley Of the Colorado in southwestern
Arizona, the rainfall Is less than three
inches and represents the extreme ARID
ity of the United States At Yuma,
eight inches In three months, January
March, the most ever recorded, fell IN
1905. Heavy precipitation over the
southwest plateau, coincides win stu
tIonary ,.yclonic periods, during when
the continued cold from the north acts
upon the winds that circulate about
the cyclone or storm center, till ram
finally falls.
THE CANYON BREEZE.
The most delightful OF our weather
phenomena is the canyon breeze IN
summer Those who live IN canyons,
or not far from the lower end tmouth)
of any canyon gorge, are familiar with
this gentle air movement, which Is. III
some instances and for certain portions
of the year. almost as regular In re-
currence as the land and sea breezes or
the coasts. The wind blows up the
canyon In the daytime and down the
canyon at night. Tho regularity and
the velocity OF this breeze viii vary
with local conditions, and sometimes IL
is overcome by larger. general winds
This breeze occurs, though often but
gently. on the slopes of all the larger
mountains. The transition from the
duwnfow for the night to the upfiow of
tl.,. lnx. 10 lFftAQ N
yons but is slow in the valleys; and
the duration of the breeze varies a good
deal with the local topography.
The night wind results. from the
natural slope of the surface which car
ries the cold mountain air of evening
much like a downstream current, INTO
the warmer valley bottoms. The can
yons, owing To their greater altitude.
their forest areas, the proximity or
snow-covered places, and the shorter
time during which they receive direct
sunshine, are cooler than the valleys at
night, so that the evening wind blows
from the cooler canyons 10 the broader,
sun warmed valleys or plains lower
down: and the conditions may he such
that this wind prevails Throughout
most of the day.
The flow of the day-wind up the
canyon or mountain side is not easily
explained without the use of a dia-
gram. II, however, we imagine tho
air as standing in one column over the
valley and in another column upon tne
mountain. IL Is apparent that the lat
ter Is shorter by the amount of the
elevation of the mountain above the
valley. AS the air next to the earth
becomes heated. the air columns ex-
pand, the expansion being proportion
ate to their respective lengths, the
warm air nearest to the earth expand
VI. s,ufn htF
some of the lower air, causes the col
umn of air at given level over the
valley to be heavier than at the base
of the column at the same level on
the hillside. The heavier column from
over the valley. therefore. moves to-
ward the mountain side and causes
breeze up the slopes or UP the canyon,
generally towards noon or afternoon,
dying away us the sinking sun nears
the western horizon.
1t is this breeze which affects most
favorably the summer climate of the
semi-arid valleys. At the writer's
home, just within the mouth of the
City Greek canyon this breeze blows
on every summer night, and seems to
bring from the hills, cooled by the
evening radiation, fresh supplies of
ozone and vigor; 1t makes breathing
a luxury and outdoor sleeping a covet-
cd enjoyment. This cool and fragrant
wind. often bearing the balsam odors
of pine and cedar. somehow reminds
one OF the days of childhood and early
youth, 1t signs softly. but is cheerful
and invigorating, and puts into a per-
son the stamina of endurance for an
other warm day Reclining on the
warm earth of the mountain slope, the
words of an olden rhyme luls one to
sleep, as at eventide in other days;
and
"Once again, as Of old. when the pine
breeze blows,
Mid the quaking asp groves I'd lie;
Where the gila CLEANS and the
columbne glows,
Near the cool stream sparkling by"
THE CYCLoNIC STORMS.
Cyclone is the word now used to
describe our greater atmospheric dis
turbances. In a cyclonic storm. six
conditions are prominent. G) There
is a central region of low pressure
0ight air, due to warmth and mois-
ture) around which the air is moving
In great curves from right to left
counter clockwise, 90 There is great
cloud area. from which rain or snow
falls. CD There are winds successive
~ changing their direction and tenn
perature as the storm arises. culminat-
os. and moves on eastward. (4) The
mass of air moving about the central