The Glasgow courier. [volume] (Glasgow, Mont.) 1913-current, 1921-09-16
RAINY CYCLE
IS FORECAST
State PHOTOGRAPHER Takes Past Rec
ord AS Guide For Pre-
dictiOn.

Montana next year and possibly for
the two succeeding years is held out to
those who accept the theory of George
Henry Ellis, state photographer, that
precipitation runs here on a f~ive-year
cycle.
MI. Ellis has prepared a chart
showing the rainfall year by year in
each of the five districts into which
Montana has been divided by the
weather bureau and the rise and fall
in the marks which represent precip-
~itation is so regular in blocks of five
as to give visual confederation, at
least, to this novel suggestion.
Makes No Prophetic Claim,
The state photographer, however,
makes no claim of being a weather
prophet. He thinks the cycle theory
is interesting and has prepared the
following explanation of it for the
public:
ut has been customary in the past
to state the amount of rainfall which
might be expected by any locality, as
the average annual total for as many
years as records have been kept at
that place. Since the precipitation
for any given year will vary consider
ably from this average, a study has
been made of the records of Montana,
to show the amount of variation which
may be expected, and to determine
whether there is any regular cycle of
wet and dry years.
Confused by C~loudbursts.
"The greatest difficulty in a study
of this sort seems to come from the
local cluodbursts, which, covering only
a few square miles, do not affect the
general condition of the state. When
those few square miles, however, hap
pen to include one of the measuring
cans, the record for that station does
not represent the condition of every
much of the territory around it. In
order to determine the average rather
than "freak" conditions, the attempt is
made to drown the effect of these local
storms by plotting the averages of a
large number of stations. Since the
distribution of the rainfall throughout
the year is as important as it's annual
ted as totals for such month. A few
of the most noticeable of those freak"
months have been disregarded, and
with that exception this study COM
prises every precipitation record which
is published by the U. S. weather bu-
reau for the state of Montana.
Divide Montana Into Sections.
"The weather bureau has divided
Montana into five sections: No. 26
being the southeastern, q the south
central, % west of the Continental di-
vide, 20 the northcentral, and 80 the
northeastern. On a diagram for each,
the total precipitation for all stations
reporting in that section is shown
graphically for each month.
"The chart shows, among other
things, that there has not been a year
quite so dry as 1919, since 1889; there
have been other dry years, as we all
know, but the extremes have occurred
only once in 80 years. Other dry peri
DDS have been 1867, 1904, and 1910.
Starting with 1901 and 1902, which
were fairly wet, the records show a
downward tendency until the dry year
of 1904. After 1904, they slope up
ward to the wet year of 1906, 1907, or
1908, in the different sections; after
which they get drier again until 1910,
which will be remembered as the year
of the forest fires. After 1910, the
tendency is upward to the good years
of 1914, 1915, and 1916; and then
downward again with some Irregular
tiles, to the real bad one of 1919.
Since 1919, the tendency seems to
be upward to the wet years which may
be due in 1922, 1928, or 1924, but when
we try to predict the weather we are
taking chances, because there is no
known method of making it act like
we think it ought to, and the cycle is
too irregular, and the data too meager
to be absolutely sure that our guesses
are correct.
However, for a person whose bust
ness demands that he bet on weather
conditions one or two years hence, this
chart furnishes as remarkable a basis
on which to make that bet, as the
writer knows Of to date"