Although I was not able to retrieve the full articles, it looks to me from the abstracts as though climate models were “tested” in the sense of seeing how well they fit with data that’s already available.
To me, testing a model would mean using it to make predictions about the future and seeing if they come true.
It’s analagous to technical analysis of the stock market. It’s very easy to come up with models that fit well with data we already have. It’s another matter entirely to use one of those models to make predictions about the future.
How much would you pay for a stock market model that has been “tested” by making sure that it fits well with historical data?
Are you claiming there is as much evidence for a god as there is for AGW? Or are you claiming that proponents of AGW haven’t accepted the burden of proof, and satisfied it for pretty much all climatologists? Or do you think that any dissension at all is equivalent to not meeting the burden of proof?
You’re quite right, I did oversimplify. But for a state to be even quasi-stable, within the quasi-stable regime, there has to be a negative feedback mechanism acting to oppose perturbations. Otherwise a little push like the “year without a summer” I mentioned earlier would flip us into an ice age. And negative feedback is rarely mentioned in these discussions.
Ice Ages are a good example. GIGObuster mentioned Milankovitch_cycles, which affect solar forcing. But the strongest climate correlation is with the 100,000 year cycle, which has the weakest impact on solar forcing. There’s something missing from the picture.
Nice point on the convergent series. I’m going to have to think about that for a bit, it’s entirely possible I’ve been mistaken about a few things.
As I thought was pretty clear, I was making the point that LilShieste seems to want to have it both ways. When someone affirmatively claims the existence of God, the burden falls to them to prove said existence. Fair enough. But when there is a dispute over AGW, he shifts the burden to those who doubt or question the affirmative claim, rather than have it fall to those who make the affirmative claim. As I’m sure you realize, though there might be a correlation between GW and man-made CO2, correlation does not equal causation. Add to that that the earth has been warming and cooling since its creation and that accurate models are probably beyond our capability, I am surprised that so many people just adopt the theory of AGW as fact. Or that the degree of AGW is significant assuming it does come into play.
Take the case of the Mt. Pinatubo study. The data from Mt. Pinatubo was not used to develop the model. In that sense, it is an after-the-fact test.
Also, even to the extent that certain historical data was available at the time that the models were developed, the models are not empirical or phenomenological models. They are mechanistic models based on our understanding of the physics involved. There are some aspects such as cloud formation that have to be parametrized but the number of parameters is way smaller than the number of degrees of freedom so it is not possible to use the parameters to fit very many aspects of the historical climate record. And, in fact, the parameters tend to be constrained by physical considerations and, to the extent they are tuned, tend to be tuned in order to get some basic aspects of the climatology right not, for example, to reproduce historical global temperature trends.
By the way, here is a discussion of how well the climate model used by Jim Hansen in 1988 to make projections has done in the intervening two decades. (Note that he made three different projections depending on future manmade and natural forcings so it is first necessary to decide which of the projections corresponds to the actual forcings that occurred and then to see how well the model predicted the global temperature rise.)
I agree with you, to a point. Yes, the onus of proof falls on the submitter- if theists are required to prove the existence of their god, then AGW proponents should be required to prove the anthropogenic nature of global warming.
However, it’s been done. Hundreds of times. And yet, every time we have a global warming thread, we get posts claiming that there’s never been any proof of humans causing global warming. The cites get posted, again. And in the very next GW thread? More calls for cites, as if those previous links had never been posted.
I’d say, at this point, it’s up to the AGW deniers to prove that the cites and reasoning which have been presented are insufficient. We’ve already done our part.
Well, if you want to put it like that… then yes, that’s what I’m saying. I wouldn’t necessarily say it “is unprecedented”, but rather it “hasn’t happened in a very long time.”
I would be interested in seeing your evidence to the contrary, though. That is, any other 125-year period in which the temperature has risen (or even dropped) by at least 0.0064 degrees per year.
" :rolleyes: " indeed.
When people make the affirmative claim that there is a God, the burden of proof falls to them.
When people make the affirmative claim that the effects of global warming are being influenced by human activity, the burden of proof falls to them.
In one of these cases, the burden of proof has been met by disclosing data, predictions, etc. from numerous studies. (Unless, of course, you can show me peer-reviewed journal articles describing the measurable existence of a God.)
So, the evidence has been presented, and the point has been made. The burden of proof now lies with the people who are trying to refute this evidence (i.e., prove that there are catastrophic faults in every single bit of evidence presented).
LilShieste
The fact that the overwhelming majority of climatologists think there is sufficient evidence for AGW to meet the burden of proof (no faith involved) shows that it is different from religion. Once a scientific “fact” has been established (actually a well supported theory) the burden of proof shifts. Someone not believing in the atomic model now has the burden of proof, right? So does a creationist.
You say that the earth has been warming and cooling as if this were news to climatologists. Clearly, it’s not the fact that the temperature is changing, but the speed of the change is what is important. Plus, the change in sea levels that have happened in the past would be catastrophic if they happened today. We’re not just a herd of animals that can slowly migrate to new homes.
Correlation does not always equal causation, but we just don’t have that, we have a mechanism for the CO2 to affect the climate also. When I was a kid the tobacco companies used to go on all the time that the correlation of smoking and lung cancer did not mean causation. I’m not sure if the exact mechanism was ever found, but now we know there is causation.
I think perfect models are beyond our capability, but not accurate ones. They improve all the time with more variables, better equations, and more computing power, but if they have good predictive ability we can’t just ignore them.
I’d say that the case for AGW is a lot better than the case that tax cuts for the rich improve the economy. The models of climate are better, there is more good evidence, and the mechanism is better understood. Perhaps we should have put the burden of proof on Bush, and maybe the right should have opposed the tax cuts until they were met.
I can do better than that. Your own graph shows a temperature drop of more than 0.2 degrees C between 1900 and 1910. That’s more than .02 degrees per year, or more than triple the rate of temperature change that you claim is unprecedented (or hasn’t happened in a really long time).
A similar rapid drop occurred between 1940 and 1950, according to your own data.
Before you go down this line, consider that there have been times when there was vastly more CO[sub]2[/sub] in the atmosphere, yet the Earth sufferred ice ages even then.
There is no simple link between CO[sub]2[/sub] levels and temperature. There may be a complex one, but there’s no simple one.
That may be, but it doesn’t contradict my statement that AGW hasn’t been tested.
Again my question:
How much would you pay for a stock market model that has been tested by seeing how well it fits with historical data?
What somebody needs to do is dig up his 1988 paper and put the actual emissions figures into the model. Assuming he actually published his source code.
If this is true (and, I don’t honestly know whether or not scientists believe that they have good enough knowledge, particularly temporal resolution, of CO2 levels and temperatures in times before ice core data to say this with confidence), what this shows is that CO2 isn’t the only quantity influencing the temperature, which we know to be true. However, over the geologic timescales that you are talking about, there were consider variations in other important factors including the earth’s orbit, quite possibly the solar irradiance, and even where continents and mountain ranges were located…all which we would expect to have an important influence on the climate!
Over the timescale over the last ~750,000 years, over which we have good data from ice cores, the correlation between temperature and CO2 levels is very strong. On the timescale of about a century that we are currently interested in, the other factors that I mentioned are varying even more negligibly than they have over the last 750,000 years…and so the variation in CO2 levels is the most important variation.
Surely you jest. The profitability from corn-based biofuel is high enough that it would make economic sense to turn fallow land into active cropland without affecting the food supply one whit.
Finally, we get to the crux of the matter. What you’re really saying is that the concept of AGW meets your religion’s definition of a “false god.” Then you make the unsupported leap to “AGW is a religion.” Do you know of any theologist, scientist, philosopher, atheist, or practitioner of any other religion that would agree with your position? Anyone with any credentials whatsoever?
Not really. Trusting a group of people in their area of expertise, when the level of agreement is this large isn’t faith, it’s trust. And no, it’s not the same as “trusting” a priest/prophet/whatever on God, because priests have no evidence God exists, and no track record of understanding or having a better connection to God than anyone else.
Fine, it’s not often mentioned by laymen ( but certainly is by actual scientists ), but so what ? Of course negative feedback exists, but there’s no reason to believe that will convieniently keep the global climate where we want it, when it hasn’t in the past. And climatologists do factor negative feedback into thier models; this is a non-issue.
How much would I pay for a model with coefficients set with data from, say 1990 - 2000 that could accurately predict the market from2001 to now? Quite a lot, actually. That’s the only way of testing a model without waiting for years to see how it does in the future.
Are you accusing modelmakers of being stupid or dishonest enough to set their model based on all historical data and then say it is tested?
Strike one, that link I cited shows how corn prices have ALREADY shot up causing real hardship to people in Mexico, and that trend is expected to continue, unless someone steps in and passes laws against it.
Strike two, money is well recognized in Christian circles as a possible false god. For that matter anything you make your life’s priority. God wants to be first, put anything or anyone above God and that becomes your god. The process of worshiping god is your religious practices.
Without a huge amount of trouble, one put together 100 different models of the stock market using yearly stock market averages from 1990 to 2000 and run them all out to 2006. Most likely, 1 or 2 of the 100 will match the more recent data pretty well.
How much would you pay for those 1 or 2? More than $1000? More than $10,000? More than $100,000?
Personally, I would pay nothing.
Not exactly, but I’m taking issue with the manner of testing. Ultimately, it appears that AGW supporters are not seriously risking their hypothesis.
But here’s a test that would satisfy me and could possibly be done today:
Take the source code from Hansen’s 1988 model and re-compile it using known figures for emissions. Compare it to actual temperature data. I predict a bad fit. (This experiment could be done only if Hansen actually published the source code for his model.)
As said, according to YOUR religion. You have no evidence that puts God above money as something deserving of worship. You have no evidence that there is a “true” god, in order for something else to be a false one. You have no evidence that we should go along with God’s desire to put him above everything else even if he existed.