, 1922-06-26
Weather Theory

1t has been said hat the general
grand currents of the atmosphere and
the thunder showers they carry are
unaffected by the minor elevations of
the earth's surface. While some claim
that showers run in valleys. II is prob
able that tho vast heights of thunder
heads render them independent of
everything but the highest mountain
ranges, except thai their weight gives
them a tendency to run" In valleys
within As degrees Of their course. But
while neither the main currents nor
their storms are seriously affected by
contour, 1t is equally evident hat the
temperature Of these currents may be
considerably altered. the change prog
ressing over a spell of days, by a GER
tam temperature Of h ground over a
comparatively great n
This change in temperature may al
so have an effect in changing humid
Try. II the southwestern deserts Of
the United States were large enough
they would probably cause consider
able difference in the rain bearing
strata. North of the equator these
rain bearing currents ave an average
direction Of northeast by east. The
rain maps OF the world show hat the
rainfall increases In hat direction less
than in others. The once great Amer
lean desert, now largely cultivated.
stretched over Kansas; the great Sa-
hara itself reappears far to the north
east as the desert of Cobb, in Asia
South of the equator the correspond
ing winds are northwesteriy. The
Chilean deserts appear to shade to the
southeast the other side Of the Andes
Similarly he dry interior of Australia
seems to continue southeastward-
II the general rain maps of the
world show UGH evidence it is not
unreasonable to that h com
ponent parts that make up the annual
rain records present similar aspects.
I am going to add five days to the
warm period half OF my temperature
forecast, which you published. By
the regular cycle of the middle period
the relatively warm half of the period
due to enc after the first few days
of June, its elimination succeeded by
the relatively cool half. to continue to
the middle of the month. The coolness
las appeared in the Canadian north
west, where the thermometers have
shown temperatures around the freez-
ing point for days But in the states
the heat and considerable dryness per-
sist. We have mere an example of
how the ground itself helps intensified
conditions to the point of exaggera-
ton.
In winter this is very plainly seen in
the case OF cold waves. A high en-
tiers from the northwest and grows
with increasing cold in the states,
though all the time 1t is moving south
in latitude. But though the cold in
.creases. there Is not the delay in
the case of heated spells. for the form
er are positive and push on; the sum-
mer cool wave. although positive. is
8 o much lighter its pushing force is
1t is apparent, then, that having the
materials" to construct long range
forecasts in outline. notifications
must be introduced to account for time
discrepancy in summer which are not
needed in winter. The effect of the
heat radiation from h earth must
computed, just as in the cold sea-
ION h radiation must be calculated to
the intensity of the cold. |
1t is wen known that the great
st cold. 9o.6 below zero. is not at the |
pole, but is a cold OF radiation in
South Siberia. Neither is the greatest