If I remember right, the basic eureka moment behind string theory came from the realization that a zero dimensional object (a point) cannot physically exist in our multi-dimensional universe. I suppose that's one way of putting it. One dimensional strings soften the ultraviolet divergences that plague zero dimensional point particle theories (quantum field theory). At at a very crude level, it's because particles can interact at a point, but strings don't have a well-defined point of intersection; they come together smoothly. This "fuzzing out" of the interaction has mathematical consequences for the renormalizability of the theory.
(This is not, however, the original motivation that led to the discovery of string theory in the first place, which had to do with trying to invent a theory of the strong nuclear interaction.)
What I find interesting is that we think we know we are made of solid matter yet we also know that all matter is ultimately made of the three primary forces of our universe we have discovered (weak, strong, and electromagnetic) and "solid" matter is really simply a collection of these forces that tend to stay in the same place for a while and interact in specific ways with other collections of the three primary forces. Matter is made up of matter, not forces. Forces are what bind the matter together.
And before anyone say "What about gravity?, Einstein says gravity is the result of mass (the three primary forces) interacting with the spacetime continuum (whatever that is). In other words you are not made of a force called gravity, your interaction with spacetime manifests itself as a force we call gravity. In string theory, you can treat gravity as an interaction like the other forces, and recover the Einstein's curved spacetime picture (although often not in a very elegant way, given the background dependence of perturbative string theory).
You can say the same about quantum field theory. QFT is a framework; you can write down specific models in it, some of which (such as the Standard Model) are testable, and some of which are not (e.g., models with all the masses up near the Planck scale). You can do the same in string theory: there are testable string models, and others that are not testable. String theory isn't developed enough to tell us which of those models may be correct, but then again, QFT doesn't tell us which model is correct either. Experiment does that.
If string theory is a failure, then alternatives such as loop quantum gravity are far more than that. They also have not been testable yet, and are not obviously any more predictive than string theory, given the infinitude of quantization ambiguities that plague other approaches. Loop quantum gravity also uses non-standard quantization rules with no experimental justification and is not yet even well defined. String theory is much better defined, at least as much so as quantum field theory is, and has a demonstrable low-energy limit which recovers QFT+GR, unlike other approaches.
Perhaps all approaches to quantum gravity are failures, but string theory still deserves the lion's share of the funding. And it's not like loop quantum gravity, Smolin's favored approach, is being starved out of existence. In fact, it is still growing in terms of researchers and funding.
Below I'd like to repost something I once wrote trying to explain why string theorists think string theory is an important approach, to counter the inevitable "it's not science" claims I see on string-related threads.
(I would like to note first that Smolin himself has written string theory papers, and historically has advocated combining string theory with loop quantum gravity, so even he doesn't think string theory is nonsense — he just would like to see it mesh with his own theories and doesn't like the attention it gets relative to them.)
Anyway, my two cents on string theory and its justification and testability:
First, string theory could certainly be tested if we could probe the Planck scale. We will never be able to build an accelerator to do that directly. There is some chance we might eventually do it indirectly by measuring fluctuations in the cosmic gravitational wave background. In addition, string theory encompasses many scenarios in which the string scale could be probed at much lower energies, but nobody is very confident that those scenarios are likely to be correct.
That being said, there is a serious possibility that string theory might not be testable in practice, at least in the foreseeable future. I don't believe that puts string theory totally outside the realm of science altogether. String theory does at least make predictions, even if we can't test them. But that is a weak argument. More strongly, string theory is motivated by reason of consistency with known physics. Gravity has to be reconciled with quantum theory somehow. There are strong reasons to believe that string theory overcomes obstacles to quantizing gravity in a unique way that all other approaches can't duplicate, although this can't be proven. That is one of the main reasons why string theory is taken so seriously despite its experimental shortcomings (which are not surpassed by its alternatives, either).
Here are a couple of arguments in favor of string theory put forth by string theorists which I have begun to agree with:
In particle physics, it has been possible to write down theories of the non-gravitational forces while being ignorant of high energy Planck scale physics. This is essentially due to the Applequist-Carrazone "decoupling" theorem, which uses renormalization group arguments to show that low-energy physics can be made independent of high energy physics, because at sufficiently low energies you can't excite the higher-energy modes; therefore, their contribution is irrelevant.
This decoupling breaks down for gravity. Because gravity is a universal interaction, it couples to everything (because everything has mass-energy); the low energy effects of quantum gravity are never independent of high-energy physics. So you can't write down a theory of quantum gravity unless you purport to know everything about particle physics up to arbitrarily high energies — which of course you can't possibly say, unless you can do experiments at the Planck scale.
This is a criticism that string theorists level against loop quantum gravity. LQG is usually attempted ignoring all realistic particle physics, and even if that approach succeeded, you'd have to write down a different LQG theory to take into account real particles, which might work completely differently than a vacuum LQG theory. LQGers respond by saying that they want to start by just proving it's possible to quantize *any* kind of gravity using this approach, and then worry about "realistic gravity".
String theory, on the other hand, evades the whole problem. It has a very unique mathematical structure which provides "mysterious" exact cancellations at all orders, rendering low energy physics decoupled from high energy physics despite the universal coupling of gravity. Thus, it can make predictions about high energy physics even without our being able to make measurements at that scale. No other approach to quantum gravity has shown any signs of being abl
Ooops, here's my previewed version that closes the quotes...
This entire global warming, the cause and what to do about it apear to be more agenda drivin then anything.
You continue to confuse the political case for action with the scientific case for what has happened.
And they do have arguments to support their opinions.
Fine. Pick one such argument and we'll discuss it. Then perhaps you will see that there are actual reasons why their opinions are in the minority.
I'm not the one holding onto something as if it was the gospel and fearfull to the point of not entertaining the thought it could be wrong
I am not holding onto anything as if it were "gospel" or that I can't be wrong. You simply refuse to admit that the scientific evidence for anthropogenic global warming has by now been strongly supported by the evidence, and the debate has moved on to what warming may happen in the future.
It apears when all natural greenhouse gasses are taking in comparison to man made GHG, we only contribute to around less then half a percent of the total green house effect.
True, but irrelevant. The vast majority of the greenhouse effect has been present throughout the history of the Earth and is why the planet has had a livable climate. Our GHG emissions have warmed the Earth by an amount on the order of 1 degree. That is much smaller than the tens of degrees that the natural GHGs warm the Earth, but the whole global warming debate is about the few-degree increase that is predicted to occur.
And to belive unconditionaly that man mad green house emision is the underlying cause of global warming, we have to discount effects from changes in the weather patterns wich keep a reletive stable earth temperature but shows increases in temperatures were the records are taken,
Believe it or not, regional climate variability is taken into account when constructing global temperature averages.
we would have to not consider natural fenominoms like elmino and it's bretheren, volcanic activity (both gas emisions as well as heat, dust and other atmospheric effects), we would have to ignore deforestation and reforestation (wich could account for some weather system changes),
Believe it or not, the El Nino Southern Oscillation is taken into account when studying climate trends, as well as volcanic emissions, deforestation, and reforestation. As one example, Pinatubo's 1991 eruption is very visible in the observational record.
we would have to exclude any inacuracies of the oceanic temperature were they measure the intake temperature of cooling water on ships to determin the air temperature and later foudn that to be inacurate,
Sampling bias is also known and corrected for; I believe Smith and Reynolds at NOAA/CDC have studied the particular issue you mention.
We would have to forget about takeing C02 readings in specific geographical locations at certain times (like at night when plantlife aspires or durring rush hour near the freeway) as one study was found to be doing,
Our CO2 readings are far more comprehensive than "one study" (and I would like to know what study that was).
An most importantly we would have to forget that we cannot even predict natual occurances like elmino and sunspots or solar activity.
We can, however, measure them, so while they contribute uncertainty to our predictions about the future, they are irrelevant to the discussion of anthropogenic contributions to global warming in the past and present.
So there is some information that isn't acurate because of our own limitations or inocent inconsistancies in data colection that when combined with other data leaves a good room for doubt to the amount of influence that is actualy caused by man.
There's room for doubt, until you actually sit down and read all the studies which correct for biases, quantify
This entire global warming, the cause and what to do about it apear to be more agenda drivin then anything.
You continue to confuse the political case for action with the scientific case for what has happened.
And they do have arguments to support their opinions.
Fine. Pick one such argument and we'll discuss it. Then perhaps you will see that there are actual reasons why their opinions are in the minority.
I'm not the one holding onto something as if it was the gospel and fearfull to the point of not entertaining the thought it could be wrong
I am not holding onto anything as if it were "gospel" or that I can't be wrong. You simply refuse to admit that the scientific evidence for anthropogenic global warming has by now been strongly supported by the evidence, and the debate has moved on to what warming may happen in the future.
It apears when all natural greenhouse gasses are taking in comparison to man made GHG, we only contribute to around less then half a percent of the total green house effect.
True, but irrelevant. The vast majority of the greenhouse effect has been present throughout the history of the Earth and is why the planet has had a livable climate. Our GHG emissions have warmed the Earth by an amount on the order of 1 degree. That is much smaller than the tens of degrees that the natural GHGs warm the Earth, but the whole global warming debate is about the few-degree increase that is predicted to occur.
And to belive unconditionaly that man mad green house emision is the underlying cause of global warming, we have to discount effects from changes in the weather patterns wich keep a reletive stable earth temperature but shows increases in temperatures were the records are taken,
Believe it or not, regional climate variability is taken into account when constructing global temperature averages.
we would have to not consider natural fenominoms like elmino and it's bretheren, volcanic activity (both gas emisions as well as heat, dust and other atmospheric effects), we would have to ignore deforestation and reforestation (wich could account for some weather system changes),
Believe it or not, the El Nino Southern Oscillation is taken into account when studying climate trends, as well as volcanic emissions, deforestation, and reforestation. As one example, Pinatubo's 1991 eruption is very visible in the observational record.
we would have to exclude any inacuracies of the oceanic temperature were they measure the intake temperature of cooling water on ships to determin the air temperature and later foudn that to be inacurate,
Sampling bias is also known and corrected for; I believe Smith and Reynolds at NOAA/CDC have studied the particular issue you mention.
We would have to forget about takeing C02 readings in specific geographical locations at certain times (like at night when plantlife aspires or durring rush hour near the freeway) as one study was found to be doing,
Our CO2 readings are far more comprehensive than "one study" (and I would like to know what study that was).
An most importantly we would have to forget that we cannot even predict natual occurances like elmino and sunspots or solar activity.
We can, however, measure them, so while they contribute uncertainty to our predictions about the future, they are irrelevant to the discussion of anthropogenic contributions to global warming in the past and present.
So there is some information that isn't acurate because of our own limitations or inocent inconsistancies in data colection that when combined with other data leaves a good room for doubt to the amount of influence that is actualy caused by man.
There's room for doubt, until you actually sit down and read all the studies which correct for biases, quantify uncertainties, and so on. After that, there
Here's a more recent example: Don't Believe the Hype and Climate of Fear, both by Richard S. Lindzen, the Alfred P. Sloan Professor of Atmospheric Science at MIT.
Okay, that's one scientist. Is that supposed to support a position that there is scientific uncertainty about the origin of global warming?
As for the IPCC, it's hardly a sterling example. Most of the signers were political representatives.
Wow, just a minute ago, it was one of thousands of groups supporting the skeptical position. As soon as I point out that they don't agree with your position, suddenly they become a meaningless data point.
Tell you what, why don't you look at the published literature and see how strong the evidence is against anthropogenic global warming, and what fraction of papers support this conclusion. For that matter, let's just continue the scientific discussion we're having below. As all your claims have been wrong or irrelevant so far, perhaps repetition will drive home the point.
What I'm pointing out is that, contrary to popular belief, carbon dioxide is not responsible for most of the heat retained by the greenhouse effect.
Who cares? That has nothing to do with global warming, so why are you even bringing it up?
Even if the amount of CO2 in the atmosphere tripled, it would still be a distant second to water vapor.
Again, so what? Tripling the CO2 certainly would certainly cause a great deal of global warming.
I've never seen any 50-year lag in the temperature/CO2 record. What is the reference for that claim?/> The direct reference is Kicking the Sacred Cow, chapter 35.
I meant an actual scientific reference. Where can I find this "detailed analysis of the timings"? (You'll forgive me if I don't just take Hogan's word for it, considering how he has championed practically every nutball denialist cause from the 20th century.)
As you point out, this might cause even more increase in temperature, some sort of vicious cycle of greenhouse warming. Historically that hasn't happened.
Hardly. Historically, the vast majority of warming has taken place after the CO2 has started to increase; see here.
Most of the warming in the 20th century, about 0.5 C, occurred before 1940 while 80% of the CO2 increase happened after that time. You can't evade those facts.
I certainly can evade those "facts"; they're wrong. Most of the warming of the 20th century occurred after 1940 (see here). However, if you consider the period 1910-1940, that had as much warming as the period 1940-2006 (although not as much warming as the period 1950-2006).
What you neglect to consider is that CO2 is not the only contributor to climate. (You make a big point of it elsewhere, but ignore it here.) You have to consider what the natural forcings are doing. In fact, it has been known for some time that the natural forcings have been contributing to cooling since the last half of the 20th century. (This is part of what the media hyped as "global cooling" a few decades ago.) The warming due to an increase in CO2 is somewhat offset by this, producing less overall warming than CO2 alone would predict.
In any case, the idea that we as humans have all that much influence on the global climate is far from being accepted by all "reputable" scientists, much less proven to be true.
It is not only accepted by the vast majority of reputable climatologists, it is strongly supported by both data and physical modeling. The debate now regards how much warming we're going to see, not whether we're having an influence on it.
I personally don't find the evidence that human activity is responsible all that compelling.
There is no undenyable, indesputable evidence that PROVES humans to be the cause of warming temperature. There is however data that sugests it to be the case. The data, as well as the physics, do far more than "suggest" it to be the case at this point.
It is when people question this conclusion that they are labeled and shunned aside. So instead some scientist just aren't speaking out and you are mistaking the silence for agreement. Scientists are not shunned for having contrarian opinions. They are, however, expected to have arguments against anthropogenic global warming that are as strong as the arguments for it. They do not.
Your not in a position were you are willing to admit to anything else or even consider it. You're not in a position to evaluate what I am or am not willing to "admit". You complain about how the brave climate skeptics are "labelled" and "shunned" by the dastardly uncritical consensus, but if anyone expresses the opinion that the case for AGW has finally been scientifically established, you label them "brainwashed" and pitiable.
You don't need to be a rocket scientist or even some sort of atmospheric scientist to know that when report produced by the "notable, acredited agencies" (ipcc, nas, US national research council,jont science academies of the G8 nations, etc..) have constantly referenced models proven to be wrong time after time. All models are "wrong", in the sense that they never describe anything perfectly, but the climate models in question are accurate enough to predict that warming will continue over the next century (though they disagree as to the extent), and they are unquestionably accurate enough to model the warming that has already taken place.
This means several things. First, they aren't claiming that there is proof of anything. There is never "proof of anything" in science, but they do claim that humans are responsible for most of the warming that has taken place over the last 50 years.
second, they weren't looking for any other reasons. they were looking at the Co2 emisions and other greenhourse gasses and the effects of it.
Utter nonsense. There are many factors at work in the climate, from GHGs to aerosols to atmosphere-ocean couplings to solar forcings, ad nauseum, and climatologists look at all of their contributions to temperature change, both positive and negative.
Yet, when someone objects to the findings (even obvious objections like the rise in sea levels that have been proven incorect or the temerature increases we should have seen by now not apearing) they are labeled, shuned, and forced away by sudo religious leaders claiming global warming is real and you need to repent or the mighty global warming catastrophy will kill you. Don't be such a jackass. Peruse the actual scientific literature on the subject. There is all kinds of discussion of various failures of climate models and predictions. (Just make some attempt to distinguish between, say, "there is a bias in upper tropospheric humidity estimates" and "our model can't predict warming or cooling".) Incidentally, the temperature increases and sea level rises we see are fully consistent with what was predicted 15 years ago.
With phrases like, "forced away by sudo [sic] religious leaders claiming global warming is real and you need to repent or the mighty global warming catastrophy will kill you", it is apparent you are not the unbiased critical thinker you imagine yourself to be. You're both biased and ignorant.
Several quite reputable scientists, many of them atmospheric specialists, dispute the political correct "consensus" that claims global warming is a result of human industrial activity. Look up the Heidelberg Appeal, the Leipzig Declaration, and the scientific community's response to the Kyoto Accords and the Intergovernmental Panel on Climate Change for some (thousands) of examples.
Hiding behind claimed "thousands" of studies that "agree" with you is not a convincing means of argument. I am quite certain you have never read most of those documents. The IPCC, in particular, has concluded that the warming in the last 50 years is primarily anthropogenic in origin — the opposite of what you claim. The Heidelberg Appeal makes no reference to global warming. The Leipzig Declaration is 10 years old (since when the case for AGW has only strengthened), contains numerous signatories with dodgy or nonexistent climatology credentials, and at best represents only a tiny minority of climate scientists. As for the scientific community's response to Kyoto, some have agreed with it, some have disagreed on economic grounds, some have disagreed with it for not going far enough, but very few have claimed that it's addressing a phenomenon for which human beings are not responsible.
Between 95% and 99% of the greenhoust effect is caused by water vapor. That's right, good old H2O, dihydrogen monoxide, is the cause of 32 degrees of the warmth trapped by our atmosphere.
That's a specious argument. The existence of H2O is why the Earth isn't 32 degrees colder than it is. But the amount of H2O in the atmosphere doesn't explain the increase in temperature in recent decades.
CO2 is responsible for maybe one degree, and only 2% of the 1,800 billion tons of CO2 in the atmosphere can be tied to human activity.
Once again, what's relevant here is not the absolute amount, but the change. Roughly half of the change in CO2 from pre-industrial times is due to anthropogenic sources, and through climate nonlinearities, those sources are responsible for most of the warming since pre-industrial times.
We're not really making that much of a difference in this way.
Compared to what the temperatures would be if there was no H20 or CO2 in the atmosphere, we're not making much of a difference. But that's the wrong question. The question is, how much of a difference have we made to the temperatures over the last 150 years, and how much difference will we continue to make in the future? Using the IPCC point estimate of 3.5 degrees warming by 2100, that's not compared to the 32 degrees that H2O has already warmed the Earth, but compared to today, 3.5 degrees is a significant change in climate.
Another point to consider is that historically the rise in CO2 levels that is tied to temperature increases follows the temperature rise by about 50 years. In other words, the rise in temperature would seem to be the cause of the increased CO2, not the other way around. This makes sense, given the amount of CO2 trapped in permafrost and the oceans.
I've never seen any 50-year lag in the temperature/CO2 record. What is the reference for that claim?
There is, however, an 800-year lag in the paleoclimate record during deglaciations, in which the temperature rise does precede the CO2 rise. As you say, warming liberates trapped CO2. What you ignore is the fact that this new CO2 in the atmosphere amplifies the warming over what it would be otherwise. You can't evade the fact that Earth gets hotter when there is more CO2 in the atmosphere.
While many models have been shown to be amazingly accurate over short periods of time and small geographic areas, that hasn't translated to equal accuracy for the global climate over a century of time.
They get more inaccurate over century time scales, certainly. But they're not totally unreliable either. And they all predi
The creators of the global climate models themselves say they still have not reached the level where they have any predictive value. That's not wholly correct, and it also neglects that the averaged predictions of several models do have predictive value. (See the references here for a more detailed discussion.) It is also worth noting that it's practically impossible to get cooling out of any model using realistic assumptions; they all have varying degrees of warming. Modeling is a lot cruder than people would like, but it's not totally useless either.
No, actually we don't know that. Yes, actually, we do. 20 years ago that wasn't the case, but now it is.
There are some theories that suggest that, but it seems that the better and better the models get, the less impact it looks like we have. That's exactly wrong. The case for primarily anthropogenic global warming is today stronger than it ever has been.
Pluto is warming too! [...] We aren't causing this warming as humans. That is a nonsensical argument. As the article you link to says, Pluto's warming is because it has been close to the Sun recently. That has little to do with why the Earth is warming.
but there is too much unclear data as to what exactly is warming our planet. I'm sure that we contribute to the warming, but so does the sun, so does a depleting ozone layer, so do many things We contribute to the warming. So does the Sun. The depleting ozone layer actually cools the planet slightly. We can calculate the relative magnitudes of these effects, and while there is always uncertainty in any measurement, we know that our greenhouse gas emissions are the dominant factor. This simply is not in scientific doubt in any longer.
Global warming, at this point, is a theory (based on observation, without contradiction), but it's not a very good one. It's falsifiable, but not in our lifetimes, and not under laboratory conditions. Global warming is not a theory, it is a prediction of our theories of the climate. Our theories of the climate can be and have been tested in many ways, and are certainly falsifiable. "Laboratory conditions" is a red herring; many sciences (astronomy, geology, paleontology,...) are based on observations instead of lab experiments, but that doesn't make them poor science. While it's nice to be able to control experimental conditions in a laboratory, it's not necessary to the practice of science.
Global warming is, at this point, a reliable prediction of climatological theory. The uncertainty is to its extent, not whether it exists.
Human activity being the root cause of the currently observed global warming is, at this point, a hypothesis. It is, at this point, a confirmed hypothesis. The uncertainty is no longer over whether we're responsible for most of it — we are. The uncertainty is about how that will affect the climate in the future.
Second, there are many distinguished scientists who doubt the anthropogenic global warming hypothesis. The question is, what fraction of distinguished climatologists doubt the anthropogenic global warming hypothesis?
Yesterday's National Post in Toronto had an article about an Oxford professor, reknowned for his studies of solar activity, who believes our current warming is driven by intense sunspot activity, and that we will experience cooling when this activity dies down. He has at least as much data to support his hypothesis as the man-made GW activists do. Great, a guy who studies the Sun thinks the Sun is responsible for everything. What a surprise. But what does he know about the climate? In fact, climatologists are well aware of the existence of solar variations, have studied the issue, and concluded that while they do contribute to global warming, their contribution to recent warming is much smaller than that of other sources, most notably anthropogenic greenhouse gas emissions.
GW believers predict that each 10% rise in CO2 concentration in the atmosphere would result in 30 cm rise in sea levels. But atmospheric CO2 has risen 100% in the last 100 years. Thus, we should see sea levels 3 m, or more than 10 feet, higher than they were a century ago. While I have not checked your figures, I can tell you that sea level rise is a nonlinear phenomenon, and it is not the case that a given fraction of CO2 rise corresponds to the same amount of sea level rise, and it is certainly not the case that 20th century CO2 level rise predicted a 3 m sea level rise.
"2006 was the warmest year in 1000 years". Either (1) They stopped looking after 1000 years, which is bad science in a billion-year cyclic environment, or (2) 1000 years ago, it was hotter. That's a simplistic assessment. First, due to fluctuations in temperature, there can be years which are unusually hot, but what is more important is what the climate trend is doing. Second, of course there are periods of time in the Earth's past that were hotter than it is today — try the Cretaceous. But it didn't get that way all of a sudden — that's why it's more relevant to compare the climate today to what the climate was doing relatively recently, not to what it was doing at some random time in the past. The issue with global warming is that there is a unprecedentedly sudden and high rate of warming which coincides in both timing and magnitude with industrial emissions of greenhouse gases. That warming is not because some billion-year cycle just happened to be due right now, and in fact the paleoclimate record does not imply that we are in for natural climate change that looks anything like what's happening now.
Finally, noone seems to really pay attention to the impact of ocean currents on atmospheric heat... they all seem to think that atmosphere is the only factor. You are joking, right? There is a huge industry of oceanic climatologists. Ever hear of an "atmosphere-ocean general circulation model" (AOGCM)?
Namely... the impact of the Atlantic Conveyor on atmospheric heat, and the impact of freshwater on the Atlantic Conveyor. Uh... that is a huge industry in climatology too. See the North Atlantic thermohaline circulation. A shutdown of the Atlantic Conveyor is thought to be responsible for the last ice age (the Younger Dryas. You may also recall a (greatly exaggerated) movie on the topic a few years back: "The Day After Tomorrow".
Some answers to your questions according to the climatology community:
1. Is the Earth warming up too fast. I.e. Will this trigger an effect outside the normal cycle. We already have warming that is outside normal variations. But what "too fast" means is subjective.
2. What effect is that? Will we go into a Greenhouse spiral and become a humid furnace like Venus? or breakup the icecaps so that when they reform the planet plunges into a freeze cycle and becomes a virtual snowball with no summer. Neither of those outcomes are plausible even under the most extreme scenarios. Some outcomes can be pretty bad, though (e.g., melting of the Greenland or West Antartctic ice sheets), although the most extreme scenarios are not as likely.
3. Is the current warming cycle being hurried along by humans? Unquestionably.
Global warming is happening, but why it is happening is what is under serious debate. The looney crowd shouting "they sky is falling" uses a scientific study that completely ignores long term historical trends. From what it looks like, the earth is in a NORMAL warming cycle and there's not a damn thing humans can do anything about it. That's not correct. Long term paleoclimatologies have not been ignored. The rate of global warming exceeds natural warming trends and the excess is completely in line with anthropogenic forcings. It is no longer under serious debate that we are responsible for most of the warming that has taken place in the last 50 years.
However, you're correct that there is a lot of debate as to how much we can do about it. Cutting our emissions back may not be good enough, considering how much CO2 is already in the atmosphere. Figuring that out means getting a better handle on the feedback mechanisms at work.
What we should be doing is getting decent theories on the extent of the warming trend and taking measures if necessary, e.g. if crop growth is going to plummet, we need to stockpile food with long shelf-lifes to prevent world wide famine. That's right. Much work is going into reducing the uncertainty about the future warming trend. Plans of action are being studied as well, but those are harder, because you have to deal with economic and political uncertainties as well as climatological ones.
Thats exactly it. The world is getting warmer. I doubt anyone is disputing that. The thing in question is what is the driving forces for it and wether man plays a significant role in those forces and whether or not it is a natural occurance as science has proved it happened before man was around. That's not in question. We know the world is getting warmer and we know that we're responsible for most of that warming, although not all of it. The question is about how much warming we're in for in the future, and the extent to which our actions can alter the outcome.
But if you object to any of the leading theories today. Many of them being spouted by people not really qualified to make those asumption, they you are the kook, crackpot whatever. It's fine if you object to a theory being pushed by someone not scientifically qualified to judge the theory. However, when you yourself are not qualified, and you object with well-established scientific results, then yes, you're a kook.
Even if you come up with the dumbest "we are walking on thin ice" theory that show man as the cause you are hailed why anyone who objects is shunned. This isn't about people objecting to what some dumb nutball on the street comes up with to support global warming, it's about people objecting to the scientific community comes up with regarding global warming, which is a different issue.
Yes, It has become about politics, funding, and multinational redistribution of wealth Certainly those are prevalent in the discussion of "what should we do". But the scientific discussion of "what is actually happening" is on quite a different level, as is the discussion of "what may happen in the future".
This movie by algore isn't supposed to educate as much as it is supposed to indoctinate people into some semi religious experience. Well, I have mixed feelings about showing that movie in schools myself. The scientific statements in the movie are largely correct and well explained at a lay level, but he definitely played up the worst-case scenarios, and it's unquestionably designed to strike an emotional chord. So on the whole, I'd prefer a more neutral presentation of the matter. (I should note that a "neutral presentation" of the matter doesn't mean what climate skeptics think it means; we are responsible for most of the global warming and will continue to be so over the next century at least.)
And yes it is perfectly fair to draw conclusion about science becoming a religion when the people defending it are acting in the exact same unbendible ways. I think you need to draw distinctions between the people "defending global warming", the people who support scientific viewpoints, and the people who do science.
The "this" is that, at one time, a body of scientists claimed, with what was to them a measured and clearly defined degree of certainty, that hell was going freeze over next Thursday. No, they didn't. As I said originally, they claimed that there was a cooling trend, but that they didn't know whether in the future it would be offset by human-induced warming; they weren't able to estimate anthropogenic contributions well enough at that time. (Now they can.) They didn't claim that there likely would be continued cooling, and they certainly didn't claim that "hell was going to freeze over next Thursday" or any comparable doomsaying. The media hyped it up as "an Ice Age is coming", but you can't find anything like that in the actual papers published at the time.
The scientific community does this on a variety of subjects: size and age of the universe, intelligence, origins of life. I don't know what claims you may be referring to regarding intelligence or the origins of life, but I can tell you that the astrophysical community hasn't made any statements with certainty about the age of the universe only to do a complete 180. (They have, however, revised estimates of the age of the universe a lot, precisely because there was a lot of uncertainty about it. In fact, for most periods of time throughout the 20th century, various pieces of observational evidence led to contradictory estimates of the age of the universe, and cosmologists certainly were aware of that.)
This is a 180 in a very short period of time and that is a credibility issue. That's simply false. For more on what climatologists were saying in the 1970s, see here and here. The whole "scientists in 1970s were screaming that the Earth was doomed to a new Ice Age" is mostly a myth that is being propagated by global warming opponents, combined with sloppy reporting in two particle Newsweek and TIME articles, and one pop-sci book by Ponte.
Isn't this an indication of some form of communication problem? To what does "this" refer?
I heard recently on the radio (either NPR or Radio 4) that a lot of the trends are being based on temp data from the 60s, and later, because prior to that the data was "too inaccurate". That's not exactly what they mean. They pick a "long-term average" that's based on what the climate was doing around the 1960s, to use as a reference temperature; they of course use a period for which there was good data. The only reason they do this is because it's easier see what's going on in a graph when you're looking at small deviations around zero, rather than the absolute temperatures. And they don't look just at trends since 1960; they look at trends well before that date. Of course, the earlier data is less accurate than later data, but it's accurate enough to see trends; you can see this on graphs that have confidence intervals on them.
I, for one, would like to hear some one say "we don't know for sure" rather than "we are entering a new ice age - circa 1967" or "don't worry about the earthquakes, Sacramento will be on the coast soon due to the ice melting - circa 2007". Scientists do say "we don't know for sure", and they actually quantify that uncertainty. The media, however, is not always good about reporting this.
It is after all "all about probability" which is just a way of describing an educated guess. Absolutely right. In the last 5-10 years climatologists have been able to go past significance tests and error bars to start estimating probabilities of outcomes.
While I'm probably convince that it is the self absorbed human race that is screwing up the place, I used to live in a town with rivers you could walk on, the rise in greenhouse gases could be part of a very natural cycle which we simply haven't seen before. While there is uncertainty about future climate change, we do know enough to be sure that the rise in greenhouse gases is not just part of a natural cycle; we are able to quantify the various sources of GHG emissions from anthropogenic and natural sources.
They used to sell me ice ages based on reading tree rings - that, to me, had a degree of acceptability that the current global warming rhetoric lacks. The measurements of global climate we have in modern times are certainly more accurate than reconstructions of temperatures from tree rings, so I'm not sure what you're getting at.
Thes chart you link to is showing the amount of change occuring from year to year, not the mean temperature for that year, That's incorrect. It is the mean temperature for that year (or rather, the 5-year smoothed average temperature centered at that year), relative to a long-term average temperature. "Mean temperature change" means change relative to a reference temperature, not change relative to the previous year's temperature. That is, the temperature anomaly is T(t)-Taverage, not dT/dt.
And the MWP actually started prior to that, so we don't see the data leading into that. You can see reconstructions for farther back than that graph here (Fig. 5c). (Note the caption to this figure, which states that it is displaying reconstructions of the "global mean annual temperatures".) You can see that, as I stated, the climate in the last 50 years has become warmer than it was during the MWP.
It's not a dichotomy, it is how both sides see the others arguments.
I'm not on anybody's "side", I'm saying that your specific arguments about climate change uncertainty and future consequences are not correct.
What were the consequences of the end of the last ice age in Europe and North America?
Irrelevant. The end of the last ice age did not involve warming at the rate that is now happening, nor did it involve a large human population whose societies are dependent on certain facets of the climate. You talk about human populations migrating in the past, but it was a lot easier to migrate in the past when you didn't have influential cities with millions of people in them.
I'm sure when people initially think about that they are imagining a wall of water flooding out the cities and the whole "waterworld" scenario. When in reality it will slowly push people inland as new coastline is created.
Once again, how slow and how far are yet to be determined, and considering what fraction of the world population lives on water, it is not trivial to conclude that mitigating climate change is less expensive than relocating population centers. Rivers with highly variable water levels obviously have societies that are adapted to highly variable water levels. But they are not adapted to additional water levels due to sea level rise, not to mention all of the major rivers which are not as variable, as well as all the coastal populations which are not adapted to that kind of variability.
You arguments about severe droughts or excessive flooding, are already the norm. It is already a part of our lives to live through droughts and manage flooding.
It still costs money and lives, so the question is, does it cost more money and lives to accept and deal with extra droughts and flooding, or to prevent them? It depends on the scenario, but there are many scenarios in which the latter is less expensive.
You are arguing that it will happen more frequently but how can you say that reliably? The climate models that are in place today paint a very broad picture and the best anybody can do is guess.
You can do better than just "guess": see, e.g., the Stern report. The odds of serious impact are high enough that you have to seriously consider the possibility of mitigation even when you're not totally sure of the outcome. Decision-making and risk reduction under uncertainty is always the situation you have to deal with. Once again, you advocate "do nothing because we're not sure". Well, that's not necessarily the smartest decision even if we're not sure. Sometimes the wisest course is "take some precautionary steps because we're not sure".
I am playing devils advocate here but I truly believe that peoples reactions to global warming and the theories vary greatly based on their perspective.
Global warming will have different effects on different populations, to be sure. However, even if global warming happens to help your country's climate, you also have to consider what the effect on other countries will have on you. Economic impacts on foreign nations propagate throughout the world's economies, some countries are already getting concerned about an influx of displaced immigrants, etc.
This planet is stable and self regulating, if it wasn't then any little thing could cause a global catastrophe.
From some perspectives, "global catastrophes" do happen.
If all it took to cause an ice age was the desalination of the north sea to shut down the gulf stream, then do you really think things would be the way they are today?
Desalination of the North Atlantic is enough to induce an ice age within a decade or two, and such rapid transitions to ice ages have happened. Unlike future climate projections, this is well established fact: there are many events in the geological record in which, for instance, the cli
I'm not arguing that we do nothing. I am arguing that jumping to conclusions and hastily making over our entire economy and way of life, before we have the facts, is worse than doing nothing. This is an extreme and false dichotomy: either "do nothing", or "hastily make over our entire economy and way of life".
What is the worst case scenario here? We slowly loose coastline over a few hundred years, while enjoying warmer winters, longer and more productive growing seasons and people will be able to migrate from the equatorial regions and begin settling the arctic and antarctic. While I'm not claiming the worst case scenario is likely to happen, what you describe is not the worst case scenario. If we reach a threshold response with the Greenland ice sheet or the West Antarctic ice sheet or both, we loose a lot of coastline over less then a century; we'd be talking about evacuating New York City and such within 50 years.
"Longer and productive growing seasons" is not a foregone conclusion; global warming can cause regional weather patterns to shift and worsen conditions for agriculture. You can get more severe flooding in some areas, severe drought in others, more extreme weather events such as hurricanes and hailstorms, etc. Regional weather is much harder to predict, but reduced crop yields are as plausible as enhanced crop yields under current uncertainty.
You also act as if moving populations out of equatorial regions is a positive thing. Mass displacements can induce high economic costs, political and social unrest, and so on. And for all the new land that becomes useful, there is corresponding land that is now useless.
Once again, I'm not saying that's the scenario that's going to happen, but the whole "global warming is a good thing" argument is ill-considered at best.
Now devils advocate aside, think about what you are talking about doing to truly make the world carbon neutral. Because that's what it's going to take to completely negate mans' presence. Fortunately, we don't have to make the world "carbon neutral" in order to mitigate the effects of global warming.
You are painting a very biased story. You take only the best possible outcomes of global warming, and weigh them against the worst possible costs of reducing global warming. "I for one would rather be able to swim in December than live like a primative [sic]", as if those are the only possibilities or issues to consider. In fact, you are being absurd. While the world's coasts are probably not going to be 50 feet underwater by the end of the century, neither will global warming produce your gentle Edenic fantasy world. Some people will benefit, some will get screwed, and figuring out which is which and how much is a matter of scientific and economic analysis, not wishful thinking.
And even if things turn out better in the long run for the U.S. — as if that's the only outcome that matters here; even if the U.S. is all you care about, what happens to other countries economically and politically certainly affects us — in the short run any significant change from the status quo over a relatively short period of time will incur a high economic cost. Our society is adapted to conditions as they are now, and does not possess perfect elastic resilience. That's why we need to consider "how fast, how much, and what does it cost". You may recall, for instance, the Stern Report which concluded that the economic costs of mitigating climate change could outweigh the economic costs of climate change under business as usual. It is extremely naive to insist that global warming can have no downside and only prohibitively expensive mitigation efforts can have any effect on the climate.
Sometimes they don't [have any hope], so I put it out there bluntly and honestly. There's always time to change a career. [...] There's a fairytale that says something about accomplishing anything you set your mind to. It's a lie. While what you say is true, you also may not be a perfect judge of who is beyond hope. Be careful what you say to others.
So dust storms in the '70 kept it cool then, now there are fewer dust storms... He also says that the polar ice caps are melting because of regional climate change and because of the peculiar topography near the poles and it is on a instability border.. to many reasons sounds like a guess/theory to me. It's not totally certain what is causing the regional warming, to be honest, but it is known that the warming is regional, not global, and also that it cannot be due an increase in solar output.
Slashdot Mirror
(This is not, however, the original motivation that led to the discovery of string theory in the first place, which had to do with trying to invent a theory of the strong nuclear interaction.) What I find interesting is that we think we know we are made of solid matter yet we also know that all matter is ultimately made of the three primary forces of our universe we have discovered (weak, strong, and electromagnetic) and "solid" matter is really simply a collection of these forces that tend to stay in the same place for a while and interact in specific ways with other collections of the three primary forces. Matter is made up of matter, not forces. Forces are what bind the matter together. And before anyone say "What about gravity?, Einstein says gravity is the result of mass (the three primary forces) interacting with the spacetime continuum (whatever that is). In other words you are not made of a force called gravity, your interaction with spacetime manifests itself as a force we call gravity. In string theory, you can treat gravity as an interaction like the other forces, and recover the Einstein's curved spacetime picture (although often not in a very elegant way, given the background dependence of perturbative string theory).
You can say the same about quantum field theory. QFT is a framework; you can write down specific models in it, some of which (such as the Standard Model) are testable, and some of which are not (e.g., models with all the masses up near the Planck scale). You can do the same in string theory: there are testable string models, and others that are not testable. String theory isn't developed enough to tell us which of those models may be correct, but then again, QFT doesn't tell us which model is correct either. Experiment does that.
If string theory is a failure, then alternatives such as loop quantum gravity are far more than that. They also have not been testable yet, and are not obviously any more predictive than string theory, given the infinitude of quantization ambiguities that plague other approaches. Loop quantum gravity also uses non-standard quantization rules with no experimental justification and is not yet even well defined. String theory is much better defined, at least as much so as quantum field theory is, and has a demonstrable low-energy limit which recovers QFT+GR, unlike other approaches.
Perhaps all approaches to quantum gravity are failures, but string theory still deserves the lion's share of the funding. And it's not like loop quantum gravity, Smolin's favored approach, is being starved out of existence. In fact, it is still growing in terms of researchers and funding.
Below I'd like to repost something I once wrote trying to explain why string theorists think string theory is an important approach, to counter the inevitable "it's not science" claims I see on string-related threads.
(I would like to note first that Smolin himself has written string theory papers, and historically has advocated combining string theory with loop quantum gravity, so even he doesn't think string theory is nonsense — he just would like to see it mesh with his own theories and doesn't like the attention it gets relative to them.)
Anyway, my two cents on string theory and its justification and testability:
First, string theory could certainly be tested if we could probe the Planck scale. We will never be able to build an accelerator to do
that directly. There is some chance we might eventually do it indirectly by measuring fluctuations in the cosmic gravitational wave
background. In addition, string theory encompasses many scenarios in which the string scale could be probed at much lower energies, but nobody is very confident that those scenarios are likely to be correct.
That being said, there is a serious possibility that string theory might not be testable in practice, at least in the foreseeable future. I don't believe that puts string theory totally outside the realm of science altogether. String theory does at least make predictions, even if we can't test them. But that is a weak argument. More strongly, string theory is motivated by reason of consistency with known physics. Gravity has to be reconciled with quantum theory somehow. There are strong reasons to believe that string theory overcomes obstacles to quantizing gravity in a unique way that all other approaches can't duplicate, although this can't be proven. That is one of the main reasons why string theory is taken so seriously despite its experimental shortcomings (which are not surpassed by its alternatives, either).
Here are a couple of arguments in favor of string theory put forth by string theorists which I have begun to agree with:
In particle physics, it has been possible to write down theories of the non-gravitational forces while being ignorant of high energy
Planck scale physics. This is essentially due to the Applequist-Carrazone "decoupling" theorem, which uses renormalization
group arguments to show that low-energy physics can be made independent of high energy physics, because at sufficiently low
energies you can't excite the higher-energy modes; therefore, their contribution is irrelevant.
This decoupling breaks down for gravity. Because gravity is a universal interaction, it couples to everything (because everything
has mass-energy); the low energy effects of quantum gravity are never independent of high-energy physics. So you can't write down a theory of quantum gravity unless you purport to know everything about particle physics up to arbitrarily high energies — which of course you can't possibly say, unless you can do experiments at the Planck scale.
This is a criticism that string theorists level against loop quantum gravity. LQG is usually attempted ignoring all realistic particle
physics, and even if that approach succeeded, you'd have to write down a different LQG theory to take into account real particles, which might work completely differently than a vacuum LQG theory. LQGers respond by saying that they want to start by just proving it's possible to quantize *any* kind of gravity using this approach, and then worry about "realistic gravity".
String theory, on the other hand, evades the whole problem. It has a very unique mathematical structure which provides "mysterious" exact cancellations at all orders, rendering low energy physics decoupled from high energy physics despite the universal coupling of gravity.
Thus, it can make predictions about high energy physics even without our being able to make measurements at that scale. No other approach to quantum gravity has shown any signs of being abl
This entire global warming, the cause and what to do about it apear to be more agenda drivin then anything.
You continue to confuse the political case for action with the scientific case for what has happened.
And they do have arguments to support their opinions.
Fine. Pick one such argument and we'll discuss it. Then perhaps you will see that there are actual reasons why their opinions are in the minority.
I'm not the one holding onto something as if it was the gospel and fearfull to the point of not entertaining the thought it could be wrong
I am not holding onto anything as if it were "gospel" or that I can't be wrong. You simply refuse to admit that the scientific evidence for anthropogenic global warming has by now been strongly supported by the evidence, and the debate has moved on to what warming may happen in the future.
It apears when all natural greenhouse gasses are taking in comparison to man made GHG, we only contribute to around less then half a percent of the total green house effect.
True, but irrelevant. The vast majority of the greenhouse effect has been present throughout the history of the Earth and is why the planet has had a livable climate. Our GHG emissions have warmed the Earth by an amount on the order of 1 degree. That is much smaller than the tens of degrees that the natural GHGs warm the Earth, but the whole global warming debate is about the few-degree increase that is predicted to occur.
And to belive unconditionaly that man mad green house emision is the underlying cause of global warming, we have to discount effects from changes in the weather patterns wich keep a reletive stable earth temperature but shows increases in temperatures were the records are taken,
Believe it or not, regional climate variability is taken into account when constructing global temperature averages.
we would have to not consider natural fenominoms like elmino and it's bretheren, volcanic activity (both gas emisions as well as heat, dust and other atmospheric effects), we would have to ignore deforestation and reforestation (wich could account for some weather system changes),
Believe it or not, the El Nino Southern Oscillation is taken into account when studying climate trends, as well as volcanic emissions, deforestation, and reforestation. As one example, Pinatubo's 1991 eruption is very visible in the observational record.
we would have to exclude any inacuracies of the oceanic temperature were they measure the intake temperature of cooling water on ships to determin the air temperature and later foudn that to be inacurate,
Sampling bias is also known and corrected for; I believe Smith and Reynolds at NOAA/CDC have studied the particular issue you mention.
We would have to forget about takeing C02 readings in specific geographical locations at certain times (like at night when plantlife aspires or durring rush hour near the freeway) as one study was found to be doing,
Our CO2 readings are far more comprehensive than "one study" (and I would like to know what study that was).
An most importantly we would have to forget that we cannot even predict natual occurances like elmino and sunspots or solar activity.
We can, however, measure them, so while they contribute uncertainty to our predictions about the future, they are irrelevant to the discussion of anthropogenic contributions to global warming in the past and present.
So there is some information that isn't acurate because of our own limitations or inocent inconsistancies in data colection that when combined with other data leaves a good room for doubt to the amount of influence that is actualy caused by man.
There's room for doubt, until you actually sit down and read all the studies which correct for biases, quantify
This entire global warming, the cause and what to do about it apear to be more agenda drivin then anything.
You continue to confuse the political case for action with the scientific case for what has happened.
And they do have arguments to support their opinions.
Fine. Pick one such argument and we'll discuss it. Then perhaps you will see that there are actual reasons why their opinions are in the minority.
I'm not the one holding onto something as if it was the gospel and fearfull to the point of not entertaining the thought it could be wrong
I am not holding onto anything as if it were "gospel" or that I can't be wrong. You simply refuse to admit that the scientific evidence for anthropogenic global warming has by now been strongly supported by the evidence, and the debate has moved on to what warming may happen in the future.
It apears when all natural greenhouse gasses are taking in comparison to man made GHG, we only contribute to around less then half a percent of the total green house effect.
True, but irrelevant. The vast majority of the greenhouse effect has been present throughout the history of the Earth and is why the planet has had a livable climate. Our GHG emissions have warmed the Earth by an amount on the order of 1 degree. That is much smaller than the tens of degrees that the natural GHGs warm the Earth, but the whole global warming debate is about the few-degree increase that is predicted to occur.
And to belive unconditionaly that man mad green house emision is the underlying cause of global warming, we have to discount effects from changes in the weather patterns wich keep a reletive stable earth temperature but shows increases in temperatures were the records are taken,
Believe it or not, regional climate variability is taken into account when constructing global temperature averages.
we would have to not consider natural fenominoms like elmino and it's bretheren, volcanic activity (both gas emisions as well as heat, dust and other atmospheric effects), we would have to ignore deforestation and reforestation (wich could account for some weather system changes),
Believe it or not, the El Nino Southern Oscillation is taken into account when studying climate trends, as well as volcanic emissions, deforestation, and reforestation. As one example, Pinatubo's 1991 eruption is very visible in the observational record.
we would have to exclude any inacuracies of the oceanic temperature were they measure the intake temperature of cooling water on ships to determin the air temperature and later foudn that to be inacurate,
Sampling bias is also known and corrected for; I believe Smith and Reynolds at NOAA/CDC have studied the particular issue you mention.
We would have to forget about takeing C02 readings in specific geographical locations at certain times (like at night when plantlife aspires or durring rush hour near the freeway) as one study was found to be doing,
Our CO2 readings are far more comprehensive than "one study" (and I would like to know what study that was).
An most importantly we would have to forget that we cannot even predict natual occurances like elmino and sunspots or solar activity.
We can, however, measure them, so while they contribute uncertainty to our predictions about the future, they are irrelevant to the discussion of anthropogenic contributions to global warming in the past and present.
So there is some information that isn't acurate because of our own limitations or inocent inconsistancies in data colection that when combined with other data leaves a good room for doubt to the amount of influence that is actualy caused by man.
There's room for doubt, until you actually sit down and read all the studies which correct for biases, quantify uncertainties, and so on. After that, there
Here's a more recent example: Don't Believe the Hype and Climate of Fear, both by Richard S. Lindzen, the Alfred P. Sloan Professor of Atmospheric Science at MIT.
Okay, that's one scientist. Is that supposed to support a position that there is scientific uncertainty about the origin of global warming?
As for the IPCC, it's hardly a sterling example. Most of the signers were political representatives.
Wow, just a minute ago, it was one of thousands of groups supporting the skeptical position. As soon as I point out that they don't agree with your position, suddenly they become a meaningless data point.
Tell you what, why don't you look at the published literature and see how strong the evidence is against anthropogenic global warming, and what fraction of papers support this conclusion. For that matter, let's just continue the scientific discussion we're having below. As all your claims have been wrong or irrelevant so far, perhaps repetition will drive home the point.
What I'm pointing out is that, contrary to popular belief, carbon dioxide is not responsible for most of the heat retained by the greenhouse effect.
Who cares? That has nothing to do with global warming, so why are you even bringing it up?
Even if the amount of CO2 in the atmosphere tripled, it would still be a distant second to water vapor.
Again, so what? Tripling the CO2 certainly would certainly cause a great deal of global warming.
I've never seen any 50-year lag in the temperature/CO2 record. What is the reference for that claim?/> The direct reference is Kicking the Sacred Cow, chapter 35.
I meant an actual scientific reference. Where can I find this "detailed analysis of the timings"? (You'll forgive me if I don't just take Hogan's word for it, considering how he has championed practically every nutball denialist cause from the 20th century.)
As you point out, this might cause even more increase in temperature, some sort of vicious cycle of greenhouse warming. Historically that hasn't happened.
Hardly. Historically, the vast majority of warming has taken place after the CO2 has started to increase; see here.
Most of the warming in the 20th century, about 0.5 C, occurred before 1940 while 80% of the CO2 increase happened after that time. You can't evade those facts.
I certainly can evade those "facts"; they're wrong. Most of the warming of the 20th century occurred after 1940 (see here). However, if you consider the period 1910-1940, that had as much warming as the period 1940-2006 (although not as much warming as the period 1950-2006).
What you neglect to consider is that CO2 is not the only contributor to climate. (You make a big point of it elsewhere, but ignore it here.) You have to consider what the natural forcings are doing. In fact, it has been known for some time that the natural forcings have been contributing to cooling since the last half of the 20th century. (This is part of what the media hyped as "global cooling" a few decades ago.) The warming due to an increase in CO2 is somewhat offset by this, producing less overall warming than CO2 alone would predict.
In any case, the idea that we as humans have all that much influence on the global climate is far from being accepted by all "reputable" scientists, much less proven to be true.
It is not only accepted by the vast majority of reputable climatologists, it is strongly supported by both data and physical modeling. The debate now regards how much warming we're going to see, not whether we're having an influence on it.
I personally don't find the evidence that human activity is responsible all that compelling.
It is rather trivial to calculate the amount of g
Utter nonsense. There are many factors at work in the climate, from GHGs to aerosols to atmosphere-ocean couplings to solar forcings, ad nauseum, and climatologists look at all of their contributions to temperature change, both positive and negative. Yet, when someone objects to the findings (even obvious objections like the rise in sea levels that have been proven incorect or the temerature increases we should have seen by now not apearing) they are labeled, shuned, and forced away by sudo religious leaders claiming global warming is real and you need to repent or the mighty global warming catastrophy will kill you. Don't be such a jackass. Peruse the actual scientific literature on the subject. There is all kinds of discussion of various failures of climate models and predictions. (Just make some attempt to distinguish between, say, "there is a bias in upper tropospheric humidity estimates" and "our model can't predict warming or cooling".) Incidentally, the temperature increases and sea level rises we see are fully consistent with what was predicted 15 years ago.
With phrases like, "forced away by sudo [sic] religious leaders claiming global warming is real and you need to repent or the mighty global warming catastrophy will kill you", it is apparent you are not the unbiased critical thinker you imagine yourself to be. You're both biased and ignorant.
Several quite reputable scientists, many of them atmospheric specialists, dispute the political correct "consensus" that claims global warming is a result of human industrial activity. Look up the Heidelberg Appeal, the Leipzig Declaration, and the scientific community's response to the Kyoto Accords and the Intergovernmental Panel on Climate Change for some (thousands) of examples.
Hiding behind claimed "thousands" of studies that "agree" with you is not a convincing means of argument. I am quite certain you have never read most of those documents. The IPCC, in particular, has concluded that the warming in the last 50 years is primarily anthropogenic in origin — the opposite of what you claim. The Heidelberg Appeal makes no reference to global warming. The Leipzig Declaration is 10 years old (since when the case for AGW has only strengthened), contains numerous signatories with dodgy or nonexistent climatology credentials, and at best represents only a tiny minority of climate scientists. As for the scientific community's response to Kyoto, some have agreed with it, some have disagreed on economic grounds, some have disagreed with it for not going far enough, but very few have claimed that it's addressing a phenomenon for which human beings are not responsible.
Between 95% and 99% of the greenhoust effect is caused by water vapor. That's right, good old H2O, dihydrogen monoxide, is the cause of 32 degrees of the warmth trapped by our atmosphere.
That's a specious argument. The existence of H2O is why the Earth isn't 32 degrees colder than it is. But the amount of H2O in the atmosphere doesn't explain the increase in temperature in recent decades.
CO2 is responsible for maybe one degree, and only 2% of the 1,800 billion tons of CO2 in the atmosphere can be tied to human activity.
Once again, what's relevant here is not the absolute amount, but the change. Roughly half of the change in CO2 from pre-industrial times is due to anthropogenic sources, and through climate nonlinearities, those sources are responsible for most of the warming since pre-industrial times.
We're not really making that much of a difference in this way.
Compared to what the temperatures would be if there was no H20 or CO2 in the atmosphere, we're not making much of a difference. But that's the wrong question. The question is, how much of a difference have we made to the temperatures over the last 150 years, and how much difference will we continue to make in the future? Using the IPCC point estimate of 3.5 degrees warming by 2100, that's not compared to the 32 degrees that H2O has already warmed the Earth, but compared to today, 3.5 degrees is a significant change in climate.
Another point to consider is that historically the rise in CO2 levels that is tied to temperature increases follows the temperature rise by about 50 years. In other words, the rise in temperature would seem to be the cause of the increased CO2, not the other way around. This makes sense, given the amount of CO2 trapped in permafrost and the oceans.
I've never seen any 50-year lag in the temperature/CO2 record. What is the reference for that claim?
There is, however, an 800-year lag in the paleoclimate record during deglaciations, in which the temperature rise does precede the CO2 rise. As you say, warming liberates trapped CO2. What you ignore is the fact that this new CO2 in the atmosphere amplifies the warming over what it would be otherwise. You can't evade the fact that Earth gets hotter when there is more CO2 in the atmosphere.
While many models have been shown to be amazingly accurate over short periods of time and small geographic areas, that hasn't translated to equal accuracy for the global climate over a century of time.
They get more inaccurate over century time scales, certainly. But they're not totally unreliable either. And they all predi
Global warming is, at this point, a reliable prediction of climatological theory. The uncertainty is to its extent, not whether it exists. Human activity being the root cause of the currently observed global warming is, at this point, a hypothesis. It is, at this point, a confirmed hypothesis. The uncertainty is no longer over whether we're responsible for most of it — we are. The uncertainty is about how that will affect the climate in the future.
Either (1) They stopped looking after 1000 years, which is bad science in a billion-year cyclic environment, or (2) 1000 years ago, it was hotter. That's a simplistic assessment. First, due to fluctuations in temperature, there can be years which are unusually hot, but what is more important is what the climate trend is doing. Second, of course there are periods of time in the Earth's past that were hotter than it is today — try the Cretaceous. But it didn't get that way all of a sudden — that's why it's more relevant to compare the climate today to what the climate was doing relatively recently, not to what it was doing at some random time in the past. The issue with global warming is that there is a unprecedentedly sudden and high rate of warming which coincides in both timing and magnitude with industrial emissions of greenhouse gases. That warming is not because some billion-year cycle just happened to be due right now, and in fact the paleoclimate record does not imply that we are in for natural climate change that looks anything like what's happening now. Finally, noone seems to really pay attention to the impact of ocean currents on atmospheric heat... they all seem to think that atmosphere is the only factor. You are joking, right? There is a huge industry of oceanic climatologists. Ever hear of an "atmosphere-ocean general circulation model" (AOGCM)? Namely... the impact of the Atlantic Conveyor on atmospheric heat, and the impact of freshwater on the Atlantic Conveyor. Uh... that is a huge industry in climatology too. See the North Atlantic thermohaline circulation. A shutdown of the Atlantic Conveyor is thought to be responsible for the last ice age (the Younger Dryas. You may also recall a (greatly exaggerated) movie on the topic a few years back: "The Day After Tomorrow".
However, you're correct that there is a lot of debate as to how much we can do about it. Cutting our emissions back may not be good enough, considering how much CO2 is already in the atmosphere. Figuring that out means getting a better handle on the feedback mechanisms at work. What we should be doing is getting decent theories on the extent of the warming trend and taking measures if necessary, e.g. if crop growth is going to plummet, we need to stockpile food with long shelf-lifes to prevent world wide famine. That's right. Much work is going into reducing the uncertainty about the future warming trend. Plans of action are being studied as well, but those are harder, because you have to deal with economic and political uncertainties as well as climatological ones.
It's not a dichotomy, it is how both sides see the others arguments.
I'm not on anybody's "side", I'm saying that your specific arguments about climate change uncertainty and future consequences are not correct.
What were the consequences of the end of the last ice age in Europe and North America?
Irrelevant. The end of the last ice age did not involve warming at the rate that is now happening, nor did it involve a large human population whose societies are dependent on certain facets of the climate. You talk about human populations migrating in the past, but it was a lot easier to migrate in the past when you didn't have influential cities with millions of people in them.
I'm sure when people initially think about that they are imagining a wall of water flooding out the cities and the whole "waterworld" scenario. When in reality it will slowly push people inland as new coastline is created.
Once again, how slow and how far are yet to be determined, and considering what fraction of the world population lives on water, it is not trivial to conclude that mitigating climate change is less expensive than relocating population centers. Rivers with highly variable water levels obviously have societies that are adapted to highly variable water levels. But they are not adapted to additional water levels due to sea level rise, not to mention all of the major rivers which are not as variable, as well as all the coastal populations which are not adapted to that kind of variability.
You arguments about severe droughts or excessive flooding, are already the norm. It is already a part of our lives to live through droughts and manage flooding.
It still costs money and lives, so the question is, does it cost more money and lives to accept and deal with extra droughts and flooding, or to prevent them? It depends on the scenario, but there are many scenarios in which the latter is less expensive.
You are arguing that it will happen more frequently but how can you say that reliably? The climate models that are in place today paint a very broad picture and the best anybody can do is guess.
You can do better than just "guess": see, e.g., the Stern report. The odds of serious impact are high enough that you have to seriously consider the possibility of mitigation even when you're not totally sure of the outcome. Decision-making and risk reduction under uncertainty is always the situation you have to deal with. Once again, you advocate "do nothing because we're not sure". Well, that's not necessarily the smartest decision even if we're not sure. Sometimes the wisest course is "take some precautionary steps because we're not sure".
I am playing devils advocate here but I truly believe that peoples reactions to global warming and the theories vary greatly based on their perspective.
Global warming will have different effects on different populations, to be sure. However, even if global warming happens to help your country's climate, you also have to consider what the effect on other countries will have on you. Economic impacts on foreign nations propagate throughout the world's economies, some countries are already getting concerned about an influx of displaced immigrants, etc.
This planet is stable and self regulating, if it wasn't then any little thing could cause a global catastrophe.
From some perspectives, "global catastrophes" do happen.
If all it took to cause an ice age was the desalination of the north sea to shut down the gulf stream, then do you really think things would be the way they are today?
Desalination of the North Atlantic is enough to induce an ice age within a decade or two, and such rapid transitions to ice ages have happened. Unlike future climate projections, this is well established fact: there are many events in the geological record in which, for instance, the cli
"Longer and productive growing seasons" is not a foregone conclusion; global warming can cause regional weather patterns to shift and worsen conditions for agriculture. You can get more severe flooding in some areas, severe drought in others, more extreme weather events such as hurricanes and hailstorms, etc. Regional weather is much harder to predict, but reduced crop yields are as plausible as enhanced crop yields under current uncertainty.
You also act as if moving populations out of equatorial regions is a positive thing. Mass displacements can induce high economic costs, political and social unrest, and so on. And for all the new land that becomes useful, there is corresponding land that is now useless.
Once again, I'm not saying that's the scenario that's going to happen, but the whole "global warming is a good thing" argument is ill-considered at best. Now devils advocate aside, think about what you are talking about doing to truly make the world carbon neutral. Because that's what it's going to take to completely negate mans' presence. Fortunately, we don't have to make the world "carbon neutral" in order to mitigate the effects of global warming.
You are painting a very biased story. You take only the best possible outcomes of global warming, and weigh them against the worst possible costs of reducing global warming. "I for one would rather be able to swim in December than live like a primative [sic]", as if those are the only possibilities or issues to consider. In fact, you are being absurd. While the world's coasts are probably not going to be 50 feet underwater by the end of the century, neither will global warming produce your gentle Edenic fantasy world. Some people will benefit, some will get screwed, and figuring out which is which and how much is a matter of scientific and economic analysis, not wishful thinking.
And even if things turn out better in the long run for the U.S. — as if that's the only outcome that matters here; even if the U.S. is all you care about, what happens to other countries economically and politically certainly affects us — in the short run any significant change from the status quo over a relatively short period of time will incur a high economic cost. Our society is adapted to conditions as they are now, and does not possess perfect elastic resilience. That's why we need to consider "how fast, how much, and what does it cost". You may recall, for instance, the Stern Report which concluded that the economic costs of mitigating climate change could outweigh the economic costs of climate change under business as usual. It is extremely naive to insist that global warming can have no downside and only prohibitively expensive mitigation efforts can have any effect on the climate.