Saturday, July 10, 2010

Michael Crichton on Doom-and-Gloomsters

Here are some interesting bits from a talk that the author Michael Crichton gave at Caltech in 2003. I love the way he takes down a number of these doom and gloom predictions:
I also expected science to banish the evils of human thought—prejudice and superstition, irrational beliefs and false fears. I expected science to be, in Carl Sagan’s memorable phrase, “a candle in a demon haunted world.” And here, I am not so pleased with the impact of science. Rather than serving as a cleansing force, science has in some instances been seduced by the more ancient lures of politics and publicity.
He attacks pseudo-science:
In 1960, Drake organizes the first SETI conference, and came up with the now-famous Drake equation: N=N*fp ne fl fi fc fL
[where N is the number of stars in the Milky Way galaxy; fp is the fraction with planets; ne is the number of planets per star capable of supporting life; fl is the fraction of planets where life evolves; fi is the fraction where intelligent life evolves; and fc is the fraction that communicates; and fL is the fraction of the planet's life during which the communicating civilizations live.]

This serious-looking equation gave SETI a serious footing as a legitimate intellectual inquiry. The problem, of course, is that none of the terms can be known, and most cannot even be estimated. The only way to work the equation is to fill in with guesses. And guesses-just so we’re clear-are merely expressions of prejudice.

...

Now let’s jump ahead a decade to the 1970s, and Nuclear Winter. In 1975, the National Academy of Sciences reported on “Long-Term Worldwide Effects of Multiple Nuclear Weapons Detonations” but the report estimated the effect of dust from nuclear blasts to be relatively minor.

In 1979, the Office of Technology Assessment issued a report on “The Effects of Nuclear War” and stated that nuclear war could perhaps produce irreversible adverse consequences on the environment. However, because the scientific processes involved were poorly understood, the report stated it was not possible to estimate the probable magnitude of such damage.

Three years later, in 1982, the Swedish Academy of Sciences commissioned a report entitled “The Atmosphere after a Nuclear War: Twilight at Noon,” which attempted to quantify the effect of smoke from burning forests and cities. The authors speculated that there would be so much smoke that a large cloud over the northern hemisphere would reduce incoming sunlight below the level required for photosynthesis, and that this would last for weeks or even longer.

The following year, five scientists including Richard Turco and Carl Sagan published a paper in Science called “Nuclear Winter: Global Consequences of Multiple Nuclear Explosions.” This was the so-called TTAPS report, which attempted to quantify more rigorously the atmospheric effects, with the added credibility to be gained from an actual computer model of climate.

At the heart of the TTAPS undertaking was another equation, never specifically expressed, but one that could be paraphrased as follows:

Ds = Wn Ws Wh Tf Tb Pt Pr Pe etc
(The amount of tropospheric dust = # warheads x size warheads x warhead detonation height x flammability of targets x Target burn duration x Particles entering the Troposphere x Particle reflectivity x Particle endurance, and so on.)

The similarity to the Drake equation is striking. As with the Drake equation, none of the variables can be determined. None at all. The TTAPS study addressed this problem in part by mapping out different wartime scenarios and assigning numbers to some of the variables, but even so, the remaining variables were-and are-simply unknowable. Nobody knows how much smoke will be generated when cities burn, creating particles of what kind, and for how long. No one knows the effect of local weather conditions on the amount of particles that will be injected into the troposphere. No one knows how long the particles will remain in the troposphere. And so on.

And remember, this is only four years after the OTA study concluded that the underlying scientific processes were so poorly known that no estimates could be reliably made.

Nevertheless, the TTAPS study not only made those estimates, but concluded they were catastrophic. According to Sagan and his coworkers, even a limited 5,000 megaton nuclear exchange would cause a global temperature drop of more than 35 degrees Centigrade, and this change would last for three months.

The greatest volcanic eruptions that we know of changed world temperatures somewhere between .5 and 2 degrees Centigrade. Ice ages changed global temperatures by 10 degrees. Here we have an estimated change three times greater than any ice age.
Here's a doomsday prediction that didn't come true:
I remind you that in the lifetime of most scientists now living, we have already had an example of dire predictions set aside by new technology. I refer to the green revolution. In 1960, Paul Ehrlich said, “The battle to feed humanity is over. In the 1970s the world will undergo famines-hundreds of millions of people are going to starve to death.”

Ten years later, he predicted four billion people would die during the 1980s, including 65 million Americans. The mass starvation that was predicted never occurred, and it now seems it isn’t ever going to happen. Nor is the population explosion going to reach the numbers predicted even ten years ago.

In 1990, climate modelers anticipated a world population of 11 billion by 2100. Today, some people think the correct number will be 7 billion and falling. But nobody knows for sure. But it is impossible to ignore how closely the history of global warming fits on the previous template for nuclear winter.

Just as the earliest studies of nuclear winter stated that the uncertainties were so great that probabilities could never be known, so, too the first pronouncements on global warming argued strong limits on what could be determined with certainty about climate change.
Here Crichton takes "the science is settled" crowd on and points out they aren't doing science. They are doing religion:
We can take as an example the scientific reception accorded a Danish statistician, Bjorn Lomborg, who wrote a book called The Skeptical Environmentalist.

The scientific community responded in a way that can only be described as disgraceful. In professional literature, it was complained he had no standing because he was not an earth scientist. His publisher, Cambridge University Press, was attacked with cries that the editor should be fired, and that all right-thinking scientists should shun the press. The past president of the AAAS wondered aloud how Cambridge could have ever “published a book that so clearly could never have passed peer review.” (But of course, the manuscript did pass peer review by three earth scientists on both sides of the Atlantic, and all recommended publication.)

But what are scientists doing attacking a press? Is this the new McCarthyism-coming from scientists? Worst of all was the behavior of the Scientific American, which seemed intent on proving the post-modernist point that it was all about power, not facts.

The Scientific American attacked Lomborg for eleven pages, yet only came up with nine factual errors despite their assertion that the book was “rife with careless mistakes.”

It was a poor display, featuring vicious ad hominem attacks, including comparing him to a Holocaust denier. The issue was captioned: “Science defends itself against the Skeptical Environmentalist.”

Really. Science has to defend itself? Is this what we have come to? When Lomborg asked for space to rebut his critics, he was given only a page and a half. When he said it wasn’t enough, he put the critics’ essays on his web page and answered them in detail.

Scientific American threatened copyright infringement and made him take the pages down. Further attacks since, have made it clear what is going on. Lomborg is charged with heresy. That’s why none of his critics needs to substantiate their attacks in any detail. That’s why the facts don’t matter.

That’s why they can attack him in the most vicious personal terms. He’s a heretic. Of course, any scientist can be charged as Galileo was charged. I just never thought I’d see the Scientific American in the role of Mother Church.

Is this what science has become? I hope not. But it is what it will become, unless there is a concerted effort by leading scientists to aggressively separate science from policy.
Go read the whole speech. He walks you through other eras where "scientific opinion" got things ghastly wrong. As Crichton points out:
Nobody says the consensus of scientists agrees that E=mc2. Nobody says the consensus is that the sun is 93 million miles away. It would never occur to anyone to speak that way.
As Crichton points out: science is based on fact and not consensus. Who care how many people in 1530 thought the sun orbited the earth. Science is defined by theory & fact. Copernicus proposed the theory and over the next century the facts bore him out. Taking a tally of "scientific opinion" in 1530 has nothing to do with science.

I like all the points that Crichton makes. It is my opinion that too many scientists are mixing politics and science. And they are mixing their own "hopeful" thinking with science. And worst of all, too many are publicly making statements in areas in which they have no expertise. They are using their credentials to shout down alternative viewpoints.

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