Richard Lindzen’s 23-Year Old Forecast

  • Date: 07/01/13
  • Fabius Maximus

We’ve looked at plenty of false (or at least temporarily not proven) forecasts by American experts about wars and climate. The rule seems to be that political correctness is rewarded, irrespective of accuracy. Today we look at a speech made 23 years ago by a MIT professor.  It looks good today, still accurate despite the advances in climate science. Furthermore his forecast of no warming larger than natural variability during the next century has proven accurate so far — after 23 years have elapsed.



  1. Contempt for science
  2. Speech by Richard Lindzen
  3. Other articles by Prof Lindzen
  4. Other Climate Forecasts
  5. For More Information

(1)  Contempt for science

One of the great oddities of the debate about climate science is the contempt for scientists displayed by the lay cheerleaders on both sides. Scientists are authorities, unless they disagree with the true dogma — then they’re fools and charlatans.  Previous posts looked at forecasts that have proved false, or not correct so far.

Today we look at a speech made 23 years ago by a MIT professor.  It looks good today, still accurate despite the advances in climate science. Furthermore his forecast of no warming larger than natural variability during the next century has proven accurate so far — after 23 years have elapsed.

Speech by Richard Lindzen

In M.I.T. Tech Talk of 27 September 1989 Eugene F. Mallove describes a presentation by Richard Lindzen (Prof of the Department of Earth, Atmospheric and Planetary Sciences, MIT) to an audience of 250 scientists at the Alexander von Humboldt Foundation Colloquium.

(a)  Key Points

  • “I argue that the greenhouse effect does not seem to be as significant as suggested.”
  • “I personally feel that the likelihood over the next century of greenhouse warming reaching magnitudes comparable to natural variability seems small.”
  • “And I certainly feel that there is time and need for research before making major policy decisions.”
  • The science of global warming is “a region in which the uncertainty is vast.”
  • “The trouble with many of these {temperature} records is that the corrections are of the order of the effects, and most of us know that when we’re in that boat we need a long series and great care to derive a meaningful signal.”

(b)  About the natural variability of climate

“Climate inherently has a natural variability that is often attributed to possible variations in solar output, volcanic dust, etc. The point we have to keep in mind is that without any of this at all our climate would wander — at least within limits. The reason is that we don’t have a closed system.

“Even if the Sun’s output were fixed, even if the radiative input were absolutely constant, even if there were no change in the absorbing gases, the ocean itself can take up and store heat and release it. It has a stable layer that normally does not communicate with lower levels, but every so often there is upwelling that suddenly presents the atmosphere and the surface world with an erratic energy source.”

(c)  About Water

“Water is terrifically absorptive. We see the bumps [in the absorption spectrum] from CO2 and ozone and methane only because they occur in a window of the water vapor absorption spectrum. Water vapor is far and away the most important greenhouse gas, except for one form which isn’t a greenhouse gas: clouds. Clouds themselves as liquid water are as important to the infrared budget as water vapor. Both swamp by orders of magnitude all the others. With CO2 one is talking about three watts per square meter at most, compared to a hundred or more watts per square meter for water.

“… Upper level humidity — especially above 5 kilometers–is rather important and the models are lousy at handling this. In the models, most warming comes from the increase in water that accompanies the warming. Whether such an increase in water vapor above 5 kilometers actually accompanies warming is doubtful.

“We don’t know how to calculate cloudiness. Some studies have found that the dominant radiative effect of clouds is cooling. Only a few percent change in cloud cover will more than swamp the estimated CO2 effect, he suggested. In the current models, for reasons that puzzle almost everyone, the cloud feedbacks are positive rather than negative. That is, they increase the temperature.

“There are other tricky things that no one has explored. One example: the feedback through albedo — the reflectivity of the Earth such as can be affected by snow cover. In the models this feedback is positive, but it could as well be negative in certain ranges of temperature. On the planet the most wonderful constituent is water with its remarkable thermodynamic properties. It’s the obvious candidate for the thermostat of our system, and yet in most of these models, all water-related feedbacks are positive. I don’t think we would have existed if that were true.”

(d)  About political use of science

Comparing the greenhouse warming debate to an earlier controversy, in his 1988 book Infinite in All Directions Freeman Dyson (Wikipedia bio) wrote:

As a scientist I want to rip the theory of nuclear winter apart, but as a human being I want to believe it. This is one of the rare instances of a genuine conflict between the demands of science and the demands of humanity. As a scientist, I judge the nuclear winter theory to be a sloppy piece of work, full of gaps and unjustified assumptions. As a human being, I hope fervently that it is right. Here is a real and uncomfortable dilemma. What does a scientist do when science and humanity pull in opposite directions?

Lindzen said about this:

“It seems to me that if science doesn’t have integrity, it isn’t of much use to people.”

(3)  Other articles by Professors Lindzen and Dryson

Freeman Dyson’s views about the climate wars:  ”The Question of Global Warming“, The New York Review of Books, 12 June 2008.

Testimony of Richard S. Lindzen before the Senate Environment and Public Works Committee, 2 May 2001

One of his major recent papers:  “On the Observational Determination of Climate Sensitivity and Its Implications” Richard S. Lindzen and Yong-Sang Choi, Asia-Pacific Journal of Atmospheric Sciences, 31 August 2011 — Abstract:

We estimate climate sensitivity from observations, using the deseasonalized fluctuations in sea surface temperatures (SSTs) and the concurrent fluctuations in the top-of-atmosphere (TOA) outgoing radiation from the ERBE (1985-1999) and CERES (2000- 2008) satellite instruments. Distinct periods of warming and cooling in the SSTs were used to evaluate feedbacks.

… We develop a method to distinguish noise in the outgoing radiation as well as radiation changes that are forcing SST changes from those radiation changes that constitute feedbacks to changes in SST. We demonstrate that our new method does moderately well in distinguishing positive from negative feedbacks and in quantifying negative feedbacks. In contrast, we show that simple regression methods used by several existing papers generally exaggerate positive feedbacks and even show positive feedbacks when actual feedbacks are negative.

We argue that feedbacks are largely concentrated in the tropics, and the tropical feedbacks can be adjusted to account for their impact on the globe as a whole. Indeed, we show that including all CERES data (not just from the tropics) leads to results similar to what are obtained for the tropics alone — though with more noise. We again find that the outgoing radiation resulting from SST fluctuations exceeds the zero feedback response thus implying negative feedback.

In contrast to this, the calculated TOA outgoing radiation fluxes from 11 atmospheric models forced by the observed SST are less than the zero feedback response, consistent with the positive feedbacks that characterize these models. The results imply that the models are exaggerating climate sensitivity.

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