A reader writes:

The claim that GW is not man-made is not only denying the reality of physics (Does CO2 trap heat or does it not? How can introducing massive amounts of this material into the atmosphere not affect the climate?), it's also the lamest of excuses of these people. Even if you deny that GW is man-made, how is this an excuse for inaction? Using the same rationale, would the commenter refuse to put out the fire in his house simply because it was hit by lighting - not a man-made fire?

If torrential downpours caused waters to start rising near his house, would he stack sandbags to protect his home, or would he just blog about how his soon to be flooded house will trigger some nonsensical evolutionary change in his being? The commenter tries to compare the recent and unprecedented spike in temperatures of the past century to those which gradually occurred over eons. Truly, this is nonsense.

Another reader writes:


Your unnamed global warming skeptic has an interesting view of the benefits of global warming:
"The world's climate has always been changing, and it has always represented a stressful environment for the ecosystem. In fact, that's one of the main sources of evolution - changing climate conditions. It's no accident that the the last three million years of human evolution, in which we developed our intelligence and culture, all occurred during a time of large climate instability. These stresses forced us to evolve in order to survive. So let's not presume that all climate change is bad for us, even when it's difficult."
What strikes me about this is how close it comes to the most extreme view of laissez-faire economics, or "social Darwinism": the most successful deserve to survive, the least successful deserve to die off, and this is for the best for humanity as a whole. Since those who advocate such a position invariably classify themselves in the "deserve to survive" category, it isn't surprising that they have little or no sympathy for those who their pet system would destroy or enslave.

Likewise with the evolutionary "benefits" of global warming. Any climactic or other environmental stress strong enough to "force" evolution will result in the death of most of the human race, because that is what it takes for evolutionary competition to work- a deadly threat to the entire species. Naturally your skeptic, and those like him, have no worries about those who would die in a climactic shift, because they believe it's not going to be THEM. They're going to adapt, survive, and pass on their genes to the next generation- or so they're betting.

The catch here is that evolution is a very long-term process. Compared to evolution, civilization is an extremely SHORT-term phenomenon- and one that depends upon a stable continuity of human existence. If your skeptic can be so glib about the mass loss of life that involves, perhaps he should consider that, in that same destructive process, pretty much everything we call "civilization" today- technology, laws, art, lore, social structure- will be destroyed as well. Without the other 99% of humanity that has to die so that the fittest can be sorted out, these things simply cannot survive.

Your skeptic might be one of the adaptable survivors in a climate change disaster, but if he does, he's going to find that the world afterward is not so pleasant to live in.

Yet another reader writes:


Your AGW skeptic puts forward something of an argument. Actually, he puts forward two arguments. Neither is convincing.

S/he claims that climate change is a constant, that it drives evolution, that it can be cruel, but that it is a normal part of nature. S/he also claims that Oyster Guy's research, which serves to only to document climate change, is irrelevant to any discussion of policy, since it does not address the mechanism causing the rise in temperatures, and so is irrelevant to policy decisions that might mitigate this change.

The first point is valid as far as it goes (which isn't very far). Sure, the climate has always been in flux, but the data overwhelmingly suggests that the rate at which the current is currently changing is faster than at any time in the measurable past. Does that mean that the current warming must be anthropogenic? Of course not - one cannot observe causality. However, the AGW skeptic must take one of two positions here: The first is that the current rate of climate change is not anomalous - either it is not as great as has been indicated, or the fluctuations in the past have been greater than currently measured. The second is that it is a coincidence, that the climate just happened to go through an unprecedented change just as humanity hit the industrial revolution.

The second of these positions is more or less preposterous. The greenhouse effect is a much more convincing explanation for an abrupt change in climate than blind chance. Our records go back a very long way. Maybe too long for people to conceptualize, which may be part of the problem.

So the skeptic is left with the first position. In which case, Oyster Guy's research is relevant after all. It helps to document the magnitude of the current change. If the skeptic claims that Oyster Guy's science is of reasonable quality, and done in good faith, then the only remaining position is that scientists are underestimating the magnitude of previous climate change events. And indeed, this seems to be the position taken by this skeptic. (Although how an alleged "attempt by a small group of climate scientists to massage the data about our recent past to make it seem that our climate has been an unchanging constant for a very long time" can work, is beyond me - how can massaging the data about the "recent past" mislead us about the fluctuations of the climate over "a very long time"?) But it does seem to suggest that the skeptic trusts the work done by ecologists, but not the work done by Earth scientists.

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