Evening star. [volume] (Washington, D.C.) 1854-1972, 1895-12-05
DECEMBER WEATHER
Where the Winter Storms Form an1
Travel.
NCRlHERN And SOUTHERN CIRCUITS
Conclusions Derived From Ten
Years Scientific Study.
PATHS OF CIRCULATION


prepared for The Evening Star by the U. s.
a.,
- .t,,,. ,,,,io, 80 ~ h;,hs ona
80, a., a. I-;.o1 CT. .h,t - ohor
,ta,.;,t;, - ,ho ,,.i,,+o soason is .snaci,u,,
u '"e -. 'eo'o 10
- ~ ~, oa.,,.,s;,,. 80 a;uea,;o,, -
an % 40,
primarily ~ oe ieieiieu " inc ia1' '''f''
the sun is IN the southern hemisphere SO
that the temperatures in the polar regions
ara praotIv diminished and the barometric
- ..., MI .,, -. 80
PieaS"iee i'''eaS tope W VI
course, at practically lne Same tehpera-
ture throughout the year, but in the north
ern winter the contrast in temperature he
tnroor tho arctic and tron;c,I hollis is re,a-
i.
uNey sreat ana 'his gives all increase Vi
power to the thermodynamc engine which
the atmcsphere of the earth really is at all
ti,,as Tho effort of tho tvo regions of diff
go +,,,ora t,,ro 10 10 rostoro RI. eoui-
ieleit temperature 10 " ies'oie e et
Ibrium that Is disturbed by the solar raula-
ton, and this is accomplished by the me-
chansm of the high and low circulation
There Is no portion of the world where
this interchange of cold and warm air is
so pronounced in latitude the United
States, and this needs very clear ex-
plantation for full comprehension of the
meteorological problem 1t will not be
proper to attempt to take up this extensive
subject in a few sentences, and 1t will be
therefore passed over at this point.
Ex,,.n,,,o,, os xy,,tar we,tI,er
',,., u.
Inc tarpuieht winter circuiatioii Is chiei-
ly brought into observation by the prom
ineuce that the southern circuit attains in
,.,,.au;a,, tel tha rortbarn II will he
,.or,au,,,on.a ,ho, ,ht ,,as,io, rear tho east
iei'i''"ei GU .n"' .ie , So ~.
ern crest Oh the ROCKY mountains, III INC
reighborhood of Alberta and Montana, Is
FED in by two high pressure belts, one from
the California coast and the other from the
northwest British possessions. From this
junction main path of circulation
passes directly eastward over the lakes and
the Saint Lawrence valley to Newfound-
lard, called the northern circuit, lying di-
rectly under the axis of the great east
ward upper currents, which most Wig
orous in this latitude; the second mean
path is along the mountain slope south
eastward to Texas, thence eastward over
the gulf states to the Carolnas, and thence
northeastward to the banks of Newfound-
land. The two circuits are together like
much-bent bow with string uniting the
ends The long southern circuit is prod
uct of three operations: LIST, the continent
tai cooling of winter that favors the trans
pcrtation of highs from north to south be
fore they break up; I'd, the circulation that
builds I'D the tropical high-preSSure belt;
3D. the rapid eastward drift in subpolar
latitudes that tends to draw every high
hack into this powerful current. The first
carries the cold waves and highs from
Manitoba to Texas, the second conserves
them in the gulf states, and the third
draus Thorn northward along the Atlantic
coast tn Newfoundland OF course it is not
easv 10 separate these three interactinS
processes very distinctly but in winter it
ia not difficult to perceive their operations.
Another principle of great importance in
discussing winter circulations is the fact
that the so-called high and low pressure
bolts are somewhat inaccurately described
in this manner From mathemat teal an
aIvsis II is shown that the atmosphere cir
cuIates in sucb a way as to tend to accumu-
late With high pressure on the outer edges
NJ Tho tropics near latitude % degrees north
and SOUTH and at the same time to make
subarctlc low pressure pelt near ~. s az
tuoe % uesIg nd' La, az @ halts do
not axist In nIaca of them there is a sue
cession of highs and lows passing over these
tracks, the air tending TO mass ltSel1 IN
nearly clrcular areas aIterna a 9oi i anu
Warm'lrom WhlGh the opser'ei wi nv. en- '
tion Is derived. IN the orue[ Vi iat.,r a. cauae
ana effect the hlghs come hr5t ana the lows
follow, ana not IN the opposte seque me-
Masses OF cola ar are Duiit up III lne hish
pressure pelt by the erect Oh senerat at
n.oSpherlc Hiotlohs tne an ueaee''iiiS ioIi.
tne upper Stra'a; bet"sen wv auJlcens
hlEhS' ana also an arouhi the p'iipneis vi
large hlsh. the lows are iorineu py me. tlie az
non OF SraVltatloh. Whlcn throws tne cur
rents lhto WhirlS. uese nave the ehect Vi
FORCING the ar nach AGAIN INTO the upper
strata Wnere u ri0Ws OF IN tne general east.
WaTu urlIt. ne fHSls are lnsue up VI ar
descending through at least hVe miles OF
strata; the lows. on tne otner hand' are
FORCED up apout Two ihiies' where tley are
nearly oDhterated by !he upper currents.
me notion that the hlShs are ted emery by
the lows or that the lows are the primary
source or the circulation, mas out little
foundation, the attempt TO make the storm
energy do so much work having failed to
hnc the necessary support in modern OBJ
servations. Having thus sketched the gem
eral features of the circulation in the United
States for the winter months, We may
anime in some detail the facts as given by
ten years OF the records of the weather