delanceyplace.com 11/3/09 - global cooling

In today's excerpt - in the 1970s, the
science pages of The New York Times,
Newsweek, and other publications sounded
the dire warning of impending global cooling.
Headlines from The New York Times of
the period included "International Team of
Specialists Finds No End in Sight to 30-Year
Cooling Trend in Northern Hemisphere," and
"New Studies Point to Ice Age Again." The
excerpt below is from a New York Times
article titled "Scientists Ask Why World
Climate is Changing; Major Cooling May Be
Ahead." There were, inevitably, dissenting
voices:

"There are specialists who
say that a new ice age is
on the way - the inevitable
consequence of a natural cyclic process, or
as a result
of man-made pollution of the
atmosphere. And there are
those who say that such pollution may
actually head off
an ice age.

"Sooner or later a major
cooling of the climate is
widely considered inevitable.
Hints that it may already
have begun are evident. The
drop in mean temperatures
since 1950 in the Northern
Hemisphere has been sufficient. for example,
to shorten
Britain's growing season for
crops by two weeks. ...

"The first half of this century has
apparently been the
warmest period since the
'hot spell' between 5,000
and 7,000 years ago immediately following the
last ice
age. That the climate, at least
in the Northern Hemisphere.
has been getting cooler since
about 1950, is well established - if one
ignores the
last two winters. ...

"From the chemical composition of Pacific
sediments,
from studies of soil types
in Central Europe and from
fossil plankton that lived in
the Caribbean it has been
shown that in the last million
years there have been considerably more ice
ages than
previously supposed.

"According to the classic
timetable, four great ice ages
occurred. However, the new
records of global climate
show seven extraordinarily
abrupt changes in the last
million years. As noted in the
academy report, they represent transition, in
a few centuries 'from full glacial to
full interglacial conditions.' ...

"In a recent issue of the
British journal Nature, Drs.
Reid A. Bryson and E. W.
Wahl of the Center for Climate Research at
the University of Wisconsin cite records
from nine North Atlantic
weatherships indicating that
from 1951 to the
1968-1972
period surface water temperatures dropped
steadily. The fall was comparable,
they reported, to a return
to the 'Little Ice Age' that
existed from 1430 to 1850. ...

"There is general agreement
that introducing large
amounts of smoke particles or carbon dioxide
into the
atmosphere can alter climate. The same would
be true of
generating industrial heat
comparable to a substantial
fraction of solar energy falling on the
earth. The debate
centers on the precise roles
of these effects and the levels of pollution
that would cause serious changes. ...

"The observatory atop Mauna Loa, the great
Hawaiian
volcano, has recorded a
steady rise in the annual
mean level of carbon dioxide
in the atmosphere, amounting
to 4 per cent between 1958
and 1972. That, however, was
a period of global cooling - not the reverse,
as one would
expect from a greenhouse
effect. ...

"If worldwide energy consumption continues to
increase at its present rates,
catastrophic climate changes
have been projected by M.
I. Budyko, a leading Soviet
specialist. He says that the
critical level will probably
be reached within a century. This, he has
written, will lead to 'a complete destruction
of polar ice covers.'
Not only would sea levels
rise but, with the Arctic
Ocean free of ice, the entire
weather system of the Northern Hemisphere
would be altered."

Walter Sullivan, "Scientists Ask Why World
Climate is Changing; Major Cooling May Be
Ahead," The New York Times, May 21, 1975.