Evening star., 1940-01-13

NoteDook OF Science Progress
In Field, Laboratory
And Study
By Thomas r. Henry.
Ice ages may be caused by the sun
getting hotter.
This paradox Is expounded by Sir
George Simpson, eminent British mete-
orologist, in the annual report of the
Smithsonian Institution.
One effect of more heat from the sun,
he explains, is more evaporation Of water
from the seas. This brings more clouds.
More clouds bring more rain but, up to
certain critical point in the increase of
temperature, In the Arctic and Antarctic
this will be in the form of more snow.
The snow will pile up for millenniums
around the poles until ice masses thou
sands Of feet thick are formed. These
will start to flow northward and south
ward to latitudes where normal summer
temperature is sufficient to melt them.
The sun, it has been demonstrated, is
variable star. It's heat is subject to
rhythmic ebbs and surges. If the heat
ice age would result from the greater
cold, but astronomers have been able to
find no evidence of fluctuations suf1-
cient to cause piling up of ice.
In the second place the whole earth
would be affected. There would be
decrease in evaporation from the sur
faces Of all the oceans. This probably
would mean over long period de-
crease in rain precipitation in the tropics.
Actually there is accommodating geological
and archaeological evidence that while
the great ice sheets were flowing from
the poles there was an enormous in
crease of rainfall in low temperate and
tropic zones.
Thirdly, the ice advanced and retreat
ed in paradoxical way. During the
Pleistocene in both North America and
Europe there were four glaciations and
three interglacial periods when the ma
jor portions of both continents were free
of ice. Two of these interglacial eras
were short, one long. 1t might be ex-
pected that an interglacial period, due to
an increase in heat on the part of the
sun over an extended period would be
colo and desolate. Actually, the geo.
logical evidence now indicates, they were
hot. The average temperatures of North
ern Europe, Sir George Simpson points
out, must have been higher than they
are today. because fossils dating from
these periods are found in higher lati-
tudes than are normal for the same
creatures. at present
All this fits into the hotter sun theory
of ice ages. If the increase of solar ra-
diation were progressive eventually a
point would be reached where even the
polar regions would be warmed to a
point where the glacier building progress
would be arrested and the ice age would
come to rather abrupt end. And once
the ice was cleared from the temperate
zones they would be relatively warm.
After the solar radiation had reached
its maximum the solar ebb would set in
and the whole process would be gone
through again in reverse. Eventually the
critical temperature would be reached at
which the ice would form again.
The period between these two inter-
glacials would be short and hot. The
heat Of the sun would continue to de-
cline. Hence precipitation would de-
cline. There would be no further build
ing up Of ice no further increments from
the polar regions. The point would be
reached in temperate zones where the
balance between ice accumulation in
winter and ice retreat in summer would
be reversed.
The solar heat would reach its mini
mum and start to go up again, even
tually increasing the precipitation to the
point of renewed glaciation. This would
be long, cold interglacial period
1t is difficult to unscramble the pat
tern Of glaciations and INTERPRETATIONS
of the Pleistocene but the present evi-
dence supports hypothetical picture in
accord with the hotter sun theory The
four glaciations came in pairs The first
and second and the third and fourth
were separated by brief, warm periods.
The second and third were separated by
long, cold period.
The actual pattern of the glaciations
was curious. In both Europe and North
America it extended far south of the
present ice belt. In England as far as
the Thames and in Eastern North Amer
lea over New England. In Eastern North
America and in Western Europe also it
came considerably farther south than in
Western North America and Eastern
Europe. In other words, great arms of
glaciation seemed to follow the Atlantic.
Also it is now known that the center of
accumulation of the ice was not at the
North Pole, but somewhere in the middle
of Greenland. Furthermore, Sir George
Simpson explains, it is difficult for
meteorologists to admit that the climates
at the southern fringes of the ice belt
ever would have been cold enough to sup
port such building up of glaciers, un-
less geographical conditions were mark
edly different than at present.
Comments on Federalism
Movement in Europe.
To the Editor Of The Star:
A United States of Europe. This is