Evening star. [volume] (Washington, D.C.) 1854-1972, 1925-12-20

conditions over the North American
continent that is slowly breaking
down the contrast between the tenn
peratures OF Northern United States
and Canada and Southern United
States is seen by Henry Holm Clay
ton, one of the countrys leading mete-
biologists, who has spent 10 years IN
studying world weather conditions.
particularly as related to the heat
radia ion of the sun.
Mr.. Clayton, who is now cooper
ating with the Smithsonian Institution
in its studies of the solar constant, de-
clareS our climate is slowly changing,
decade by decade and century by CEN
fury"
Sees Contrast Weaken.
although the temperature year by
year tiuctuates widely from the aver
age" he says, there is an underlying
upward trend in the Northern Umteo
States and Canada like slowly MS
ing tide, while in the South or the
United States the trend is the othef
way. Thus the contrast between the
weather of the North and South Is
diminishing and the climate or the
country as a whole is ameiiorauns'
1T has been widely held that cllfn-,e
is a fixed quantity and that II EH nave
1t
say 80, 30 or 100 years, we can aver
age out the vagaries of the weather
and determine the real climatic con-
slant. That idea has given rise 10
another widely held view, which Is
that if the temperature or the ram
fall, for example. is above normal FOR
a few years, then later II Will be as
much below normal: so that. in the
course of time, the same average con-
dition prevails.
These ideas are being abandoned by
advanced students Of the weather,
who hold that climate as well as
weather is in a continuous stage OF
change, Thirty, fifty or one hundred
year averages have no meaning as in
dicating any fixed normal above and
below which the temperature may
oscillate but will again return to the
same level. The Investigations of A.
Z. Douglass, Gerard De Greer, Els
worth Huntington and others have
proved that climate. like weather, or
like the tides, is in continuous proc
ess of ebb and flow, and hundreds
or even thousands of years may in
tervene before the same condition re-
turns.
Other Sharp Changes.
In intervals of time measured by
many thousands of years the climate
of a place like New England may
change from condition where ice
covers the land surfaces to a depth
of thousands of feet to conditions so
mild as to be almost tropical.
Even in the course of several GEN.
turtles the climate of New England
may oScillate between cold conditions
similar to those of Labrador and mild
conditions similar to those which pre-
vail on the coast of Virginia at
present.
Regular observations of the tenn
perature at Boston and at New Haven
extends back almost to colonial times.
The observations at New Haven in
1878 and in Boston in 1890. The two
sets Of records run almost parallel.
The mean annual temperature Of the
past so years Of observations is ma
terially higher than those of the first
so years. The coolest periods record.
ed We're from 1892 to 1892, and from
1872 to 1928. Since then the trend of
the temperature has been upward
The mean temperature of the &c
years ending with 1925 is two and
SiX-tenthS warmer than the mean OF
the 10 years ending with 1921 Ii
January and July are considered
separately, it Is found that the mean
Of the past 10 Januaries has averaged
4 degrees warmer than the mean of
the 10 from 1912 to 1921, and the
mean of the past 10 Julys has aver
aged IT degrees warmer.
This progressive rise of tempera-
ture is indicated by observations taken
all over the Northern part of the
United States. In ST. Paul, Mimi, the
temperature of the decade ending
with 1925 averages 2.8 degrees warmer
than that of the first decade of OBJ
servation from 1859 to 1868.
Canadian Gain Greater.
In Canada the rise has been even
more pronounced. At Winnipeg for
the 10 years ending with 1925 the
average yearly temperature is 4 de-
grees higher than that of the first 10