Global Warming Primer
There are three separate questions:
- Is the planet becoming warmer? A tough question, knowing that calorimetry is the most delicate kind of physical measurement. What do you measure, when, for how long? Methods and opinions differ. Magic satellites giving you a single figure for easy comparison are wishful thinking. You need a data interpretation method, and that's where opinions and tempers flare.
- Is it a long-term trend? Also a tough question. Historical data is sparse and sometimes dubious. Not to mention that the methods and instruments have changed. For instance, the Albany, NY weather bureau reports average temperatures decreasing since the start of the century. Does that prove anything? Is this a fluke?
- Is the observed change man-made?Again, a difficult question. It's not like you can run a parallel experiment on a second Earth devoid of mankind, although some people are planning it. Earth went through extreme temperature swings before the first ape showed up. The Deep Core ice-sampling project showed variations of about 7C (14F) in less than a century, several times over the last 200,000 years or so. That's huge. More over, the sun activity is not a constant. Sun activity variations wiped out the Maya (see "Solar Forcing of Drought Frequency in the Maya Lowlands" and google for more.). Astronomers think that the Mars icecap hasn't grown up as large in the last Martian winter as compared to pictures sent by the Viking probes: If that's true, it's not because of human activity. Then of course there is the well-known CO2 effect. How do we separate the natural and man-made causes? What's predominent?
I don't have answers, and serious scientists are very cautious too. Good data is too scarse, and too much money is involved for rational debate.
A government submitting to the rule of experts, can lead to an unelected elite of priviledged technocrats acting as unchallenged mouthpieces that are part of the regime. You need to be careful to renew this elite and bring competition among them to avoid this phenomenon.Most debates on the subject don't even acknowledge the existence of these separate questions.
posted by pale at 11:41 AM
5 Comments:
Actually, many scientific articles have looked at the issues you've raised - and they are all legitimate questions in the global warming debate. Now that we are measuring temperature essentially all over the world and seeing a fair bit of variability, it does raise good questions about how accurate ice core and other spot data actually is. While the fact that the ice core data we do have agrees at the macroscopic scale, it is still not possible to say that we know with absolute certainty what the temperature or CO2 levels were at a specific time in the past with certainty.
You mention a decreasing temperature in one place - you might not know this, but the climate models predict just this sort of behaviour - increasing temperature in some areas, decreasing in others, dry conditions in one place and wetter in another - it's very complicated. You might be surprised to know that one of the climate predictions is that Europe could very well get very, very cold in the next few years - a "mini Ice Age" of sorts, while eastern North America will warm quite nicely. The complexity of the models do not however hide "fudges" that guarantee a global warming result - there are many models and approaches and they generally point to an overall and accelerating warming trend linked to the rapid recent increase in atmospheric CO2.
Are the changes man-made? Hard to say, but it is certainly one of the major potential factors that we cannot rule out. Historic CO2 highs are generally found to coincide with massive volcanic output, and while we have had some volcanism in the recent geologic past, it is not a particularly active period.
I don't think there are any climate scientists trying to say that variation in temperature and CO2 must be anthropogenic - there is too much prehistoric evidence that shows a natural variation. Separating anthropogenic climate effects and natural ones is not possible with 100% certainty in a mathematically chaotic system like climate. However, we can measure or estimate man-made sources and model their effects. And these models all show in relatively depressing consistency that the current CO2 increase is best explained by dirty old us.
Of course, if we want to we can cling to the hope that this science is all wrong, but that is not a safe bet. Nor is it a sane thing to do given the evidence.
government submitting to the rule of experts, can lead to an unelected elite of priviledged technocrats acting as unchallenged mouthpieces that are part of the regime.
A bit paranoid, but arguably possible. However, that is not what's happening here. Government, university, and private sector scientists from around the world have found independent evidence of global warming in almost every ecosystem. A government that pays to educate scientists and then ignore them when it hears something it doesn't like is turning it's back on reality.
As for your appeals to "competition" - the scientific community is already very, very competitive. That it has arrived at something of a consensus on global warming highlights the convincing nature of the evidence, not the lack of a search for alternative answers.
I don't know what your background is, but I have a feeling it isn't in earth or climate science. I suggest that you do some reading beyond googling a few sites before pleading for greater debate on the subject. Few topics outside of bioethics have been debated more thoroughly in the last fifteen or so years.
Kev, whats your background? Are you a climatologist? Are you one of the 60 that wrote an open letter to the PM? I think you will find that the 'consensus' among scientists and researchers in this area was that if you disagreed with the theory of global warming you would get your funding cut and be tossed out of the University or research group you were apart of.
btw, those debates have been more like lectures, very one-sided, kinda like the one you are trying to give in these here comments.
JM
Hey, I got a backround in earth. Yousta dig trenches in the army...
anonymous,
For what it's worth I'm a geologist, not a climatologist, and no, I did not sign an open letter to the PM. Alas, from what I've found on the web, those that did sign apparently did so anonymously, so I suppose I could say I did.
'consensus' among scientists and researchers in this area was that if you disagreed with the theory of global warming you would get your funding cut and be tossed out of the University or research group you were apart of.
This kind of blanket statement is impossible to argue against because there is no possibility of enough evidence to convince someone that would say anything like this. First, if you actually have tenure, you're not getting tossed out of anywhere; but you are right - money for grad students that argue against global warming might be limited in the general university community, but groups like the AAPG or ExxonMobil would certainly finance such research. Getting funding dollars means going to the right places, and there are places to go.
There are legitimate questions about global warming, some of them more valid and likely than others. Are these getting published? Some are because I've read them, but is every paper submitted being published - likely no. Whether this is the result of bias on the part of journal editorial committees or poor writing or reasoning, I don't know. A study of the editorial standards and failure/success rates across the journal community would be really interesting I would think.
As for any bias in the research community, if there is it might be related to style of science that is being funded. Mathematical modelling studies are being funded - and at our current level of understanding, they generally point toward real warming effects. Data collection research, which has generally been interpreted to indicate warming, also is being funded or funding and gear is already in place.
The kind of research that has argued against global warming effects that I've seen so far are discussions of the global warming models and alternative hypothesis. Neither of these has resulted in actual mathematical models or substantive evidence as proof, and therefore would likely not get through an editorial committee on basis of science or methodology. Where I do see some of these counter arguments published is in comments to other articles.
I understand that there is a certain amount of hostility to global warming - it means big changes for us. However, the fact is that global warming is a real, measurable and to some extent predictable event.
If a university researcher was to produce a convincing model that argued against global warming, it would get published, I have no doubt. Convincing meaning that it takes into account past and current conditions. The problem is that this has not been done, but has been in the global warming case.
those debates have been more like lectures, very one-sided, kinda like the one you are trying to give in these here comments
Guess what? I only write from my viewpoint, so it is a lecture. You add your voice and it becomes a debate
i like that pic
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