Wednesday June 25, 2008, 11:22 pm
It's not so much that all so-called global warming skeptics are lying, though no doubt some are. It's actually that most of them engage in logical fallacies that even a well educated child could see.

For example, consider the claim that in prehistoric times CO2 levels followed global temperature rises by a few centuries, instead of preceeding those temperature changes. For the tempertures to rise first is exactly what one would expect from natural climate change. Such natural change is slow and steady, but still can have profound effects over tens of thousands of years. The initial forcing agent in those cases would indeed be an increase of Solar radiation recieved by the Earth, due to either an increase in the Sun's activity or to a shifting of the Earth's orbit. As the global warming cycle begins, the slightly warmer oceans would then release CO2 into the atmosphere, causing further warming, resulting in more CO2 being released from the oceans, thus producing a feedback loop that would eventually be strong enought to melt even the extreme ice sheets of a ice age.

But to conclude that CO2 CANNOT cause global warming, to assume that the Sun must always be the forcing agent, or that there is nothing we can do about the global warming problem because of natural climate change in the past, are fallacies called non-sequiturs. Because our civilization didn't exist back then, the assumptions of the denialists simply do not apply here.

http://en.wikipedia.org/wiki/Non_sequitur_%28logic%29

(((Non sequitur (Latin for "it does not follow."), in formal logic, is an argument where its conclusion does not follow from its premises.[1] In a non sequitur, the conclusion can be either true or false, but the argument is a fallacy because the conclusion does not follow from the premise. All formal fallacies are specific types of non sequitur. The term has special applicability in law, having a formal legal definition.

Here are two types of non sequitur of traditional noteworthiness:

1) Any argument that takes the following form is a non sequitur:

If A is true, then B is true.
B is stated to be true.
Therefore, A must be true.
Even if the premises and conclusion are all true, the conclusion is not a necessary consequence of the premises. This sort of non sequitur is also called affirming the consequent.

An example of affirming the consequent would be:

If I am a human (A) then I am a mammal. (B)
I am a mammal. (B)
Therefore, I am a human. (A)
"I" could be another type of mammal without being a human. While the conclusion may be true, it does not follow from the premises. This argument is still a fallacy even if the conclusion is true. It is a non sequitur (note that it is the exact same argument form as in example 1 - the form is always a non sequitur).

2) Another common non sequitur is this:

If A then B. (e.g., If I am in Tokyo, I am in Japan.)
Not A. (e.g., I am not in Tokyo.)
Therefore, not B. (e.g., Therefore, I am not in Japan.)
The speaker could be anywhere else in Japan. This sort of non sequitur is called denying the antecedent.

(If either of the above examples had "If and only if A, then B" as their first premise, then they would be valid and non-fallacious but unsound.)

Many other types of known non sequitur argument forms have been classified into many different types of logical fallacies. In everyday speech and reasoning, an example might be: "If my hair looks nice, all people will love me." However, there is no real connection between your hair and the love of all people. Advertising typically applies this kind of reasoning.)))

The ability of CO2 to retain heat in a planet's atmosphere was first submitted by Swedish chemist Svante Arrhenius in 1896. He actually FAVORED global warming, saying it would benefit his part of the world. He went on to win the Nobel Prize in Chemistry in 1903. The confirmation of the greenhouse ability of CO2 came from studies of the planet Venus. And there is no doubt that millions of vehicles and thousands of fossil fuel burning power plants are producing CO2. And measurements of CO2 levels in the atmosphere are rising and have been for decades.

What other conclusion can we reach, but that man's actions are the primary (but not only) cause of the problem? Certainly, if CO2 level rises ALWAYS followed temperature rises, then, because CO2 levels have been measured as higher than any time over the past half a million years, Earth should have been EXTREMELY hot only a few decades or centuries ago. Instead, we had an event called the Little Ice Age. Tenmperatures are only increasing NOW, in step with the increases in CO2 happening at the same time.

Thus, the case against the man-made global warming hypothesis has no support, either empirically or logically.

Thursday June 26, 2008, 12:16 am
Another lesson in the crusade to deny man's role in global warming is the claim that "global warming stopped in 1998" and that we are cooling now. 1998 was a time of an unusually strong El Nino that acted in concert with increasing greenhouse gases to push the average global temperatures to record levels. Following that year, global temperatures remained higher on average than they were in previous decades, even, according to some reports, reaching the 1998 level in 2005 and 2007.

http://data.giss.nasa.gov/gistemp/2007/

So, we must ask, what cooling trend? 1998 was an unusually hot year. The trend is still warming over the several decades that include years both before and after 1998.

Here is another chart that shows the warming trend both before and after 1998:
http://climate.uah.edu/maps/28yeartemps.jpg