Did scientists including James Hansen predict global cooling in the 1970s?

Question

This is a frequent argument by anthropogenic global warming (AGW) skeptics, and while it wouldn't disprove AGW even if it were true, it's interesting to examine.

Here is an article on the subjecty from NASA GISS:

http://tinyurl.com/2ybgqj

"Milankovitch's theory suggested Earth should be just beginning to head into its next ice age cycle. The surface temperature data gathered by Mitchell seemed to agree...Mitchell was only collecting data over a fraction of the Northern Hemisphere...Still, the result drew public attention and a number of speculative articles about Earth's coming ice age appeared in newspapers and magazines."

But other scientists forecasted global warming. Russian climatologist Mikhail Budyko...predicted the cooling would soon switch to warming due to rising human emissions of carbon dioxide.

Hansen concluded:

“It became clear that human-produced greenhouse gases should become a dominant forcing and even exceed other climate forcings"

Any thoughts?

Answer 1

My thoughts, deniers are trying to hype it to create a distraction. So far deniers have been shown to be great magicians, but that is changing, regardless of how loud they yell. The overwhelming amount of evidence is pointing to the theory of AGW and Hansen has known for decades (along with many other scientists).

Answer 2

I think we will need to kill  bears, so we can have bear rugs too keep us warm

Answer 3

SOME SCIENTISTS WERE PREDICTING AN EMERGING ICE AGE 30 YEARS AGO.  JUST LOOK AT THE FAMOUS COVER OF NEWSWEEK MAGAZINE FROM 1975.

This statement is often repeated by global warming deniers.  It was even quoted by Sen. James Inhofe, Ranking Minority Member of the Environment and Public Works Committee, on the floor on the Senate last year.  This statement still appeals to climate change deniers because the predictions have turned out to be so wrong.  Climate change deniers therefore conclude that the science of global warming remains unsettled.

A better conclusion, however, would be that one should not rely on the mass media for your science if you can find better sources.

Now, there is an ounce of truth that some scientists during the 1970's were predicting an emerging ice age.  Such speculations were the result of: (1) a newly proven existence of ice ages, and (2) the realization that pollution could block out sunlight and cool the environment.

(1)  Ice Ages consisting of glacial and interglacial cycles had long been theorized.  Firm evidence of an Ice Age consisting of warm and cool cycles and occurring over the past few million years finally came during the late 1960's and early 1970's in the form of sea sediment cores.  The beginning and end of Ice ages are thought to be related to Milankovitch cycles or small changes in Earth's orbit and axis tilt.  The orbit of Earth will eventually wobble again and a glacial ice age will begin; this should start to occur in approximately 10,000- 15,000 years or so.

(2) Global temperatures did not decrease during the 1970's, but they were no longer increasing at the same rate as they had been.  During the mid 1970's it became apparent that man-made pollution was driving global dimming.  Pollution, such as reflective sulfate aerosols in the atmosphere, tends to have a negative radiative forcing that cools the environment by reflecting energy back into space before it reaches the surface. Clean air legislation has reduced production of industrial pollution (manmade aerosols) in Europe and North America since the 1970's. These aerosols are also the cause of such things such as acid rain.

There is a vast difference between what we know today about global warming via the greenhouse effect and what we knew then. During the 1970's, an "emerging ice age" was just speculation by the mass media. There was no widespread scientific consensus. No daily headlines. No avalanche of scientific articles in peer-review magazines. No International treaties and commissions. No G8 summits or UN Security Council meetings on the dangers of Global Warming. No calls for immediate action. Today the science is better, the evidence startling, and the research conclusive. Today there is a near unanimous consensus among scientists that anthropogenic greenhouse gases cause of recent global warming.

And no, Hansen was not one of the scientists speculating on an emerging ice age, though some deniers would like you to believe that he was.

Answer 4

What I believe is that the Earth has taken care of itself for far longer than man has been around and will continue to do so no matter what we do.

Answer 5

The Newsweek global cooling story (actual scan of article) can be found at:

http://denisdutton.com/newsweek_coolingw...

I can't find anything on Hansen and global cooling back then.  A Washington Post article in 1971 had a  prominent atmospheric scientist S.I. Rasool at NASA predicting an ice age based on a computer program developed by Hansen.

The reason the Newsweek article is so popular is that it shows how cocksure folks were about their ice age prediction (that may yet come to pass).  For example:

"The evidence in support of these predictions has now begun to accumulate so massively that meteorologists are hard-pressed to keep up with it."

People like hot weather, so a gradual rise of a degree or so over 100 years is easy to adapt to.  By contrast, an extensive glaciation would be devastating and lead to the end of life in the USA as we know it.

The "consensus" downside of global cooling is stupendous compared to any bona fide issues with global warming.

The only problem with global cooling is that mankind could not possibly be the cause ... so no blame, no evangelical meetings and exhortations, no sacrifices to the god of AGW.

Answer 6

Thirty years ago my friends and I were discussing global warming not cooling.

The theories that we were cooling have not received anywhere near as much scientific research as the idea of global warming, and the majority of the evidence says we are causing global warming.

Answer 7

I believe AGW is unprovable with the current and enormous lack of data.  I don't care who says it exists.