Last of the old MySpace blogposts:
Some interesting excerpts:
Some argue that CO2 fluctuations over the Phanerozoic follow climate trends fairly well, supporting a causal relationship between high gas levels and high temperatures. “The geologic record over the past 550 million years indicates a good correlation,” said Robert A. Berner, a Yale geologist and pioneer of paleoclimate analysis. “There are other factors at work here. But in general, global warming is due to CO2. It was in the past and is now.”
Other experts say that is an oversimplification of a complex picture of natural variation. The fluctuations in the gas levels, they say, often fall out of step with the planet’s hot and cold cycles, undermining the claimed supremacy of carbon dioxide.
“It’s too simplistic to say low CO2 was the only cause of the glacial periods” on time scales of millions of years, said Robert Giegengack, a geologist at the University of Pennsylvania who studies past atmospheres. “The record violates that one-to-one correspondence.”
He and other doubters say the planet is clearly warming today, as it has repeatedly done, but insist that no one knows exactly why. Other possible causes, they say, include changes in sea currents, Sun cycles and cosmic rays that bombard the planet.
“More and more data,” Jan Veizer, an expert on Phanerozoic climates at the University of Ottawa, said, “point to the Sun and stars as the dominant driver.”
Highlighting the gap, the two sides clash on how much the Earth would warm today if carbon dioxide concentrations double from preindustrial levels, as scientists expect. Many climatologists see an increase of as much as 8 degrees Fahrenheit. The skeptics, drawing on Phanerozoic data, tend to see far less, perhaps 2 or 3 degrees.
The Phanerozoic dispute, fought mainly in scholarly journals and scientific meetings, has occurred in isolation from the public debate on global warming. Al Gore in “An Inconvenient Truth” makes no mention of it.
Some mainstream scientists familiar with the Phanerozoic evidence call it too sketchy for public consumption and government policy, if not expert deliberations.
Skeptics say CO2 crusaders simply find the Phanerozoic data embarrassing and irreconcilable with public alarms. “People come to me and say, ‘Stop talking like this, you’re hurting the cause,’ ” said Dr. Giegengack of Penn.
So much for Al Gore’s scientific “consensus” on global warming.
It also bears pointing out that even if the evidence gathered from earth’s distant past is too sketchy for public debate, that only makes data from the more recent past and present an even less solid foundation for determining public policy. Why? Because it means we don’t know all of the factors causing global warming and how they interact, how much temperatures will change, what effects this will have, and so forth. Theories and models based on data from only the past few hundred years at most have too short a time horizon to be useful for telling us what the long term trends are and whether and to what extent human beings may be responsible. It is the height of hubris and irresponsibility to enact government policies that will have significant negative economic consequences and harm the well-being of countless people based on shaky statistical correlations and even shakier computer models. The cost of such policies is all too likely to outweigh the negative consequences of global warming.
It’s also interesting that leftist ideologues in the scientific and political community attempt to discourage less biased scientists from talking about evidence that contradicts the environmental alarmists’ public claims. Hurts the cause they say. Well, perhaps the cause is out of step with reality, eh?
Along these lines, here’s another interesting excerpt:
“Some climatologists view the Phanerozoic debate as irrelevant. They say the evidence of a tie between carbon dioxide and planetary warming over the last few centuries is so compelling that any long-term evidence to the contrary must somehow be tainted. They also say greenhouse gases are increasing faster than at any other time in Earth history, making the past immaterial.”
It’s interesting that alarmists insist on interpreting evidence from the distant past in light of evidence from the more recent past rather than interpreting any given period in light of evidence from the overall historical record. Anything inconsistent with their ideology and evidence from the recent past must be wrong. They then go on to claim that greenhouse cases are increasing faster now than at any other time in Earth’s history, but what evidence do they have for this? There is little enough data from the planet’s distant past, and much of it contradicts their alarmist claims. Indeed, sudden climate shifts are natural and not uncommon. Alarmist claims are clearly ideologically driven and based on evidence with too limited of a time horizon. They make unsupported generalizations from limited data and ignore or attempt to suppress contradictory evidence.
Be sure to check out the whole article, there are a lot more juicy tidbits.