Climate Science Is Not Settled

View 843 Saturday, September 20, 2014

“Transparency and the rule of law will be the touchstones of this presidency.”

President Barack Obama, January 31, 2009


Chaos Manor Review returns.


Climate Change

Steven Koonin, former Undersecretary for Science in the Department of Energy during President Obama’s first term, has an article in today’s Wall Street Journal that well states and summarizes the rational scientific view of the Great Climate Science Debate.

Climate Science Is Not Settled

We are very far from the knowledge needed to make good climate policy, writes leading scientist Steven E. Koonin

The idea that "Climate science is settled" runs through today’s popular and policy discussions. Unfortunately, that claim is misguided. It has not only distorted our public and policy debates on issues related to energy, greenhouse-gas emissions and the environment. But it also has inhibited the scientific and policy discussions that we need to have about our climate future.

My training as a computational physicist—together with a 40-year career of scientific research, advising and management in academia, government and the private sector—has afforded me an extended, up-close perspective on climate science. Detailed technical discussions during the past year with leading climate scientists have given me an even better sense of what we know, and don’t know, about climate. I have come to appreciate the daunting scientific challenge of answering the questions that policy makers and the public are asking.

The crucial scientific question for policy isn’t whether the climate is changing. That is a settled matter: The climate has always changed and always will. Geological and historical records show the occurrence of major climate shifts, sometimes over only a few decades. We know, for instance, that during the 20th century the Earth’s global average surface temperature rose 1.4 degrees Fahrenheit.

Nor is the crucial question whether humans are influencing the climate. That is no hoax: There is little doubt in the scientific community that continually growing amounts of greenhouse gases in the atmosphere, due largely to carbon-dioxide emissions from the conventional use of fossil fuels, are influencing the climate. There is also little doubt that the carbon dioxide will persist in the atmosphere for several centuries. The impact today of human activity appears to be comparable to the intrinsic, natural variability of the climate system itself.

Rather, the crucial, unsettled scientific question for policy is, "How will the climate change over the next century under both natural and human influences?" Answers to that question at the global and regional levels, as well as to equally complex questions of how ecosystems and human activities will be affected, should inform our choices about energy and infrastructure.

But—here’s the catch—those questions are the hardest ones to answer. They challenge, in a fundamental way, what science can tell us about future climates.

Dr. Koonin has different emphasis than I have, but nothing said in that opening summary is untrue. He is being a bit more conciliatory to the Believers than I would be, and I hope that works. I doubt that it will, and I look for denunciations of him as a traitor to mankind as one of the less severe charges to be brought against him, but the statements are true, and the analysis that follows will be at least in part familiar to long readers of this daybook.

For the latest IPCC report (September 2013), its Working Group I, which focuses on physical science, uses an ensemble of some 55 different models. Although most of these models are tuned to reproduce the gross features of the Earth’s climate, the marked differences in their details and projections reflect all of the limitations that I have described. For example:

• The models differ in their descriptions of the past century’s global average surface temperature by more than three times the entire warming recorded during that time. Such mismatches are also present in many other basic climate factors, including rainfall, which is fundamental to the atmosphere’s energy balance. As a result, the models give widely varying descriptions of the climate’s inner workings. Since they disagree so markedly, no more than one of them can be right.

• Although the Earth’s average surface temperature rose sharply by 0.9 degree Fahrenheit during the last quarter of the 20th century, it has increased much more slowly for the past 16 years, even as the human contribution to atmospheric carbon dioxide has risen by some 25%. This surprising fact demonstrates directly that natural influences and variability are powerful enough to counteract the present warming influence exerted by human activity.

Yet the models famously fail to capture this slowing in the temperature rise. Several dozen different explanations for this failure have been offered, with ocean variability most likely playing a major role. But the whole episode continues to highlight the limits of our modeling.

• The models roughly describe the shrinking extent of Arctic sea ice observed over the past two decades, but they fail to describe the comparable growth of Antarctic sea ice, which is now at a record high.

• The models predict that the lower atmosphere in the tropics will absorb much of the heat of the warming atmosphere. But that "hot spot" has not been confidently observed, casting doubt on our understanding of the crucial feedback of water vapor on temperature.

• Even though the human influence on climate was much smaller in the past, the models do not account for the fact that the rate of global sea-level rise 70 years ago was as large as what we observe today—about one foot per century.

• A crucial measure of our knowledge of feedbacks is climate sensitivity—that is, the warming induced by a hypothetical doubling of carbon-dioxide concentration. Today’s best estimate of the sensitivity (between 2.7 degrees Fahrenheit and 8.1 degrees Fahrenheit) is no different, and no more certain, than it was 30 years ago. And this is despite an heroic research effort costing billions of dollars.

These and many other open questions are in fact described in the IPCC research reports, although a detailed and knowledgeable reading is sometimes required to discern them. They are not "minor" issues to be "cleaned up" by further research. Rather, they are deficiencies that erode confidence in the computer projections. Work to resolve these shortcomings in climate models should be among the top priorities for climate research.

There is considerably more including one idea you have seen here:

A transparent rigor would also be a welcome development, especially given the momentous political and policy decisions at stake. That could be supported by regular, independent, "red team" reviews to stress-test and challenge the projections by focusing on their deficiencies and uncertainties; that would certainly be the best practice of the scientific method. But because the natural climate changes over decades, it will take many years to get the data needed to confidently isolate and quantify the effects of human influences.

I recommend that anyone, Denier or Believer, interested in the Climate Change phenomenon read this article in its entirety, then start over and read it again. It says a great deal that needs to be understood. The Climate Change phenomenon is real and has been for a very long time. How much mankind contributes to climate change is not known; we have more data than Arrhenius had at the turn of the 20th Century, but our predictions are not much better than his back of the envelope projections. The matter is important (if for no other reason than to help decide where major investments ought to be), and we are developing the instruments needed. We should continue to develop means of measuring new data and recording it, and as Moore’s Law makes our computes more powerful, we will have computers capable of using that new data. What we must not do is start with the answers before we begin seriously to study the problem.


Dr. Pournelle,

I very much enjoyed the new Chaos Manor reboot. Looking forward to more.

As predicted, the wages of nuclear diplomacy are nuclear escalation. Ukraine is not worth cold war II, but in response to largely empty U.S. threats made early in the current crisis, Russia is upping the ante:

So much for that Nobel prize for contributions to anti proliferation.

You’ve written about your early participation in operational research and space suit development, and described skin tight suits in your fiction on several occasions; everything old IS new again:


And the implications of that are far more serious than the Iraq Wars.  I lived in a time of full nuclear threat, and I don’t want to see those times again. but President Clinton chose the Muslim side in the Balkans against the Christian pan-Slavic Russians, President George Bush continued to encourage the encirclement of Russia, and President Obama despite his stated intent to ‘reset’ never understood the Russian view.  Estonia ought to be an armed neutrality like Sweden, but there is a move to turn it into a NATO fortress/base – 200 miles from St. Petersburg. Russia has always feared encirclement, and has a population crisis which means that Russia must rely on technology, not large armies and militias.

I am pleased to see that the Space Activity Suit is back in consideration, but apparently the authors of that piece are unaware that there was a lot of research into Space Activity Suit a long time ago: I have worn one in a Litton Industry test chamber at 90,000 feet altitude equivalence. This would be about 1960.




NASA’s new private man space contracts

Notice Boeing got twice what Space X did. Old habits die hard. But at least we are making progress. Perhaps Elon will just build a new space station and lease it to NASA.

Phil Tharp

Okay, this is just weird

Stephanie Osborn

Interstellar Woman of Mystery <>


There will always be an England



There will always be a large island off the coast of France…

but there is no longer an England.


I have been holding this until I could comment, but I found this story so horrifying that I have been unable to comment.


Fighting ISI

"Four squadrons of Warthogs and a regiment of Green Berets would eliminate the Caliphate in short order, …"

Would you mind terribly if we substituted a mercenary regiment? If the thugs of ISIS want to cut people’s heads off, I suspect there can still be found Gurkhas that would gladly return the favor…


Ayo Gurkhali!

Gurkhas probably could be persuaded to work for the United States (provided the Brits would agree), but Foreign Legions and other essentially mercenary armies are more suited to empires than to Republics.  They are a permanent force that can be used to intervene in other people’s affairs at low political cost; note that the original charter of the Foreign Legion was that it should never set foot in France, but then came World War I, and the incorporation of Algeria into Metropolitan France, and other such necessities.



Freedom is not free. Free men are not equal. Equal men are not free.




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