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Tricky Articles

Posted by beachofdreams on 2006.12.30 at 23:27

Sometimes we come across articles written by media pundits that, while they may seem to have good arguments, can be sorely misleading for various reasons, especially to those who have just recently become acquainted with the global warming issue and, especially, the science behind it.

I recently read a rather misleading article written on Reason.com (albeit from 2004) claiming not only that the particular scientific details of climate change are complicated (this is true) but also implied that it is not neccessarily true that the globe is warming at a rapid rate. However, if you really read the article, no good support is given for this latter claim.

The author, named R. Bailey, takes two climate studies of the polar regions and claims that these are supposed to "confirm what the majority of scientists have been saying - that man made global warming is occuring at a  rapid rate". He then goes on to raise some skeptical points towards these studies with, I think, the intention of calling into question the whole notion that rapid change is occuring. He's got his work cut out for him in two threads: 

1) he has to show that the conclusions of these studies are really in question, something which I think he does not do very well, and I will show this below. And,

2) if he succeeds at (1), then he has to show that this calls the whole thesis that "rapid global warming is happening" into doubt. Again, he doesn't actually show this (and I don't think it can be, seeing as how that thesis (i.e. global...) does not rest on observations and studies done in locales such as the Arctic and Antarctic.)

It is worth noting that this article is more suggestive than it is taking one side or the other. Still, it is always worth noting the parts that are entirely misleading; Bailey really makes this seem like a real 'controversy' when it really isn't.

His First Task

Are the polar studies really in question? Let me say from the outset that it seems as if they are from the way that Bailey argues. However, if you examine his language usage when he presents these criticisms and arguments against the studies, you can tell that he committs a rather virulent straw man argument against them. 

The first study he points to is by the Arctic Climate Impact Assessment (you can find the link on the reason.com article). He summarizes it, stating 

"They find that the Arctic region is warming at twice the rate of the rest of the world. They further find that the sea ice that covers the Arctic Ocean is thinning, and could almost disappear in the summer months by 2100.

and I will trust that this is a correct summary. 

However, take a look at how he calls this conclusion into question. He says that Christy, a scientist from the University of Alabama, has pointed to the fact that the Arctic has been warmer in the past (if you look at the records) and that it has, in the past, warmed quicker than it is today. Does this mean that the polas studies' conclusions have been called into question? No, because the Arctic could still be warming at twice the rate as that of the rest of the world and still not have reached the record temperatures that were seen in the 1930's (which are not 'rates of warming' so much as they are 'instances of higher than average temperature'). It would be like a doctor telling their patient "the rash is occuring quicker on your face and feet than it is on the other parts of your body", to which the patient replies "I don't know about that, because my worst rash happened on those same areas many years ago". Doesn't make sense, does it? Pointing the past does not refute what is happening in the present.

Other than that, it is claimed that from the late 1970's to the present, the Arctic climate has not warmed significantly. This is false, as figure 2.6 on the actual Arctic Impact Assessment Report, pg 35 of the PDF, shows.

As for the secone study, done on the Antarctic, all that is said is that Antarctica is not warming like the Arctic. In fact, he says, it is cooling. In fact, Bailey doesn't go into the implications of this study that much. All he really says is that this study shows that the 'rapid warming' thesis is more complicated than it is usually characterized to be (and so it is). A valid, if somewhat mundane argument, to be sure.

If you want some detailed discussion about the relative lack of warming in the Antarctic, then see here.

His Second Task

I think I have explained why he cannot do this above. However, it's worth pointing out that the Arctic Impact Assessment, at the very least, was never meant to be a "proof" of rapid global warming. Rather, it was a study that concluded that over the period of the last 50 years, it is probable that 'polar amplification' has occured in the Arctic (not at both the poles, like Bailey claims the study purports to show): that the Arctic is warming faster than other areas of the globe. Does this mean that they conclude that rapid global climate change is occuring? No, although they probably believe it.

One of the main problems with authors like Bailey and all of these 'experts' on reason.com is that they do not fully appreciate the difference between localized and larger scale (e.g. the globe or the Arctic as a whole) temperature averages. If you look in this particular article you'll find that local anomolies (like Greenland's temperature) are added into the mix as though they are 'points of interest' (things that make you go 'hmm"). And while any kind of local phenomena is a point of interest, they are not things that automatically throw into doubt conclusions that regard for extensive regions (like the Arctic as a whole, not just Greenland, for instance).

A Few Extras

After re-reading the article several times, I drew my attention toward some of the calculations near the end of the article. I am not knowledgeable enough to actually check whether these calculations are accurate, but I do know that the numbers (at least, the global average rise in temperature: at 0.6 degrees celcius) correspond to what I have read elsewhere and what is generally accepted as the amount the globe has warmed during the 20th century. This will be translated into roughly 1 degree F.

However, what to make of this?

"For the nationalistic, Christy's satellite data find that the lower 48 states of the U.S. are warming at a rate of 0.07 degrees per decade. If temperatures continue to increase by 0.08 degrees Celsius per decade, the planet will warm by 0.8 degrees Celsius by the end of the century. That compares to an increase of 0.6 degrees Celsius during the 20th century. Not much of a crisis..."

Wait a second, who says that this is not much of a crisis? Has the author presented any evidence to back up this claim? This translates, roughly, into a 2 degree rise over the pre-industrial average, what many climatologists have said is not a good thing. It would seem as if the author of this article assumes that such a rise is not a crisis because it does not sound like much (although he fails to account for the fact that the last glacial period was a mere 5 degrees C below the pre-industrial average. Kudos, Mr. Bailey).

Other than that, a cooling Antartica is not neccessarily a refutation of the global warming thesis, and in this Bailey is correct to point it out (however, he gives a rather bizarre qualification with support from Lindzen right after this).  Consider what RealClimate has to say about this:

...short term observations should be interpreted with caution: we need more data from the Antarctic, over longer time periods, to say with certainly what the long term trend is. Second, regional change is not the same as global mean change. Third, there are very reasonable explanations for the recent observed cooling, that have been recognized for some time from model simulations. However, the models also suggest that, as we go forward in time, the relative importance of increasing radiative effects, compared with atmosphere and ocean dynamic effects, is likely to increase. In short, we fully expect Antarctica to warm up in the future.


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