Evening star., 1896-02-07
FEBRUARY WEATHER
1t is the Month When Wintry Con-
ditions Culminate.
PROCESSION OF TIE HIGHS AND Lows
Result Of Careful Study by Weather
Bureau Experts.


1t may be noted that an attempt has
been made in previous articles of this Sc
rleS to direct attention to the Importance
of the northwest region In the meteorolcgy
of the United States. On the eastern
slope of the Rocky mountains, in the Can
adian possessions. in the neighborhood of
115 degrees w. longitude and 55 degrees
n. latitude there exists peculiar mechan-
ism whose work is to turn out series of
highs and lows, following each other in
apparently fortuitous sequence, which
then advance over the United States in
the tracks that have been described.
The leading feature in the meteorology
of the earth is the fact that the suns
radiation warns the tropical and tenn
perate zones, leaving the arctic regions
cold From this unequal temperature
there are produced confessional currents,
of which the primary are the tropical
trades blowing westerly. and the upper
current in the temperate zones, blowing
easterly. The movements of our highs
and lows have much to do with this east
ward current and upon it depends the
main eastward drift that is at the basis
of the practical forecasts of the weather
bureau. The most remarkable featGreere-
garding this eastward drift over the en-
tire hemisphere, is that sometimes it Is
very rapid and at other times very slow.
the acceleration and the stagnation sue
csed1ng each other at uncertain intervals.
1hiS lrregularity is on the whole, the
most difficult feature in forecasting to
take account of, and from it is due many
of the failures. A sudden slowing up Of
the drift will necessarily throw the whole
forecast into confusion, and an unexpected
rush will also produce disaster. This
peculiar change in rate of motion seems
to occur simultaneously over the two cou-
tinents and the two oceans, and is there
fore probably due to some great cosmical
agency at work.
Peculiar Curve,
A careful study of the succession of the
highs and lows in the northwest has re-
vealed the fact tnat there Is peculiar
curve. which they try to follow in their in
teusity, and that they tend to repeat the
same curve every 26.6S days This curve
has grand sweep with two maxima and
two ninima in it, and ten minor crests
spread along it in quite symmetrical man.
ner: the next striking popularity of the
eastward drift is that the succession of the
highs and lows Is along this curve in one
position, and then along the same curve
when 1t is inverted or turned over. This
inversion is found to occur at very irreg-
ular intervals, and yet in such way as to
be certainly connected with the motion of
the earth about the sun.
These considerations point to some kind
OF energy that comes from outside the
earth. falls upon the whole hemisphere. ana
is associated with the suns action. Finally
when the great preponderance in the num-
Der of storms In North America, over the
corresponding localities in Asia in the mid
die of the continent, is considered, the
number In America being about ten times
as great as in Asia, it Is necessary to look
for some cause that accounts for this De-
culiarity. The preponderance of storms IN
North America, the inversion of the order
OF their production, the alternate hasten
ing ard slowing UP of the eastward drift
are facts of profound meaning in seeking
the fundamental laws regarding the origin
of storms.
\ study of the variations of the magnetic
field of the earth has brought out new
series of facts that seem to be very closely
connected with those just mentioned II is
shown that field of force is impressed
upon the earth in directions that nearly
coincide with the magnetic meridians.
When this force increases an impulse is
propagated from the north to the south.
and in case of unusual disturbance the
magnetic and electric field of the earth
suffers perturoations or storms that show
themselves in all outburst Of beautiful
auroral light, or in the electric currents
that temporarily destroy telegraphic com
munication.
Belt of AurOras.
An examination of the places of the reIa-
tive frequency of the auroras sbou,s +ho+