This is the kind oftedious, petulant ad hominem routine that makes dealing with pro-AGW individuals so different from any other scientific debate.
Ha! You don't read Slashdot much, do you? Go read any of the threads on evolution, the electric universe, string theory, dark matter,...
And give me a break with the moral high horse. You're the one who ended with an insulting parting shot about how people don't critically evaluate climate science and how they're "alarmists". I didn't drop any snide remarks about "denialists" who are in the back pocket of Exxon, or anything similarly odious.
But while we're on the topic, what makes dealing with anti-AGW self-professed "skeptics" so tedious is that they tend to get all their science from skeptic websites instead of actual scientific literature. And then, unlike honest skeptics, they go out and misinform the public based on their distorted pseudo-education. I was hoping it would sink in that you're serving as a great example of what's wrong with the climate science debate, but you don't seem to have noticed.
Can we at least agree that we are not in danger of increasing CO2 levels to poisonous levels?
Sure, but since no one has claimed we are, it's irrelevant.
Society seems to have adapted rather well to a climate that was already changing (about half the warming this century seems to have happened between 1940 and 1970, and it didn't seem to bother anybody).
To the contrary, the economic damage assessments are based in part on historical records of temperature/precipitation effects on agriculture and other sectors of the economy. The global effects have been relatively small so far, since the climate change has not yet been that large, but they're not negligible either. And it's questionable at best to conclude that the impacts of climate are negligible, when the future climate change can be 4x larger than in the last century (and even larger than the change in the 1940-1970 period you mention).
Bjorn Lomborg's Copenhagen Concensus of eight world class economists started from the assumption that the IPCC's claims for future warming are reasonable and *still* concluded after a costs-benefits analysis that dealing with climate change via economic measures was a bad idea (climate change came in bottom of the list, after fourteen other proposals for improving the state of the world).
Have you read their report? Or did you just read the skeptic spin?
They didn't conclude that dealing with climate change via economic measures was a bad idea. They only said there were other things they thought should be dealt with via economic measures too, and some of them get a higher return on investment. The Copenhagen analysis is structured only to answer the question, "If we could spend money on just one thing, what would it be?" In reality, you need to spend money on all these problems. Just because you get more bang for your buck for one of them doesn't mean that you should ignore all the rest. And their analysis sometimes ignores the effect climate change has on the other problems they considered, e.g., they look at malaria but not on the climatic influences on that problem. (Or at least that's what I gathered from the challenge pieces; I never got around to reading all the supplementary perspective pieces.)
What they actually concluded is that dealing with climate change using pure mitigation is economically sub-optimal. They said that the optimal policy should include a combination of mitigation, adaptation, and technology R&D. Which is pretty much what anybody sensible says. And their optimal policy which includes CO2 mitigation as well as R&D leads to emissions in 2100 which are less than half of what the optimal policy would be if you ignored mitigation and relied only on technology improvements.
The Copenhagen Consensus did not claim that climate cha
You must live in a very different U.S. than I do. In the U.S. I'm familiar with, there have not been any "huge protests" over newspapers publishing photos of criminal suspects, having trouble renting a hotel room in cash, direct advertising, or any of the other examples the parent poster was referring to.
Everybody I have ever had a conversation with, in person, is as outraged and disturbed as you are by the erosion of privacy. [...] I would state 100,000% that ONLY companies and various organizations get represented in US government today. [...] The America you are talking about is not one that was created by the people. It was created over the protest of Americans every single step of the way.
Yeah right. Most Americans don't think about and don't care about these issues. Yeah, if you have a conversation with one they'd probably say they don't like it. Maybe they'd even be "outraged". But would that make them protest or otherwise take political action? Keep them up at night? Or even make them think much about it later? No. Not beyond a tiny minority that is over-represented here on Slashdot.
The America being spoken of was not created by corporations, but by public apathy.
We actually have a better chance of detecting the exotic particles than the rogue planets, so some people are focusing on that
It's the other way around. Dark matter in the form of brown dwarves and such has actually been detected through gravitational microlensing observations. That's how we know that most of the dark matter isn't brown dwarves and other compact astrophysical bodies; it's there, but there isn't enough of it to explain the necessary gravitational effects.
Plenty of dark matter theories have already been falsified. The majority of dark matter isn't brown dwarves, black holes, or neutrinos. The whole "hot" vs. "warm" vs. "cold" dark matter debate ended up ruling out slews of candidate particles. Many of the proposed candidates have the wrong mass. Others interact with other particles in the early universe and screw up structure formation. Some are excluded by direct searches in dark matter detectors. And so on.
And the Flying Spaghetti Monster theory passes all of them with flying colors as well.
So, no, you don't understand how science works.
The FSM isn't falsifiable, it doesn't make any specific quantitative predictions, its existence is not a natural consequence of other physical theories.
It's silly science to be saying "Dark Matter does it!" when there is literally no evidence that this nebulous "Dark Matter" even exists.
Think for a minute.
If a weakly interacting massive particle existed, what evidence would we see that it exists?
Gravitational anomalies of a very specific quantitative character on scales from galaxies to clusters to cosmology. These anomalies would not be totally independent but would relate to each other in a specific quantitative way linked by the mass of the particle. This is what we actually do see. Furthermore, the existence of these particles has been independently predicted to explain non-gravitational phenomena in elementary particle physics.
These "very specific predictions" are manufactured by scientists trying to explain the unexplainable,
Yes, we get it, you don't understand and don't like science. The fact remains is that dark matter has passed every observational test we've thrown at it, it's extremely unlikely that a random theory would pass all those tests by coincidence, the alternative theories have failed, and we have good independent reasons to believe such particles exist even if we'd never turned a telescope to the sky.
Dark matter probably collides with the Earth all the time and we don't notice since it interacts so weakly with us. It's the same with neutrinos. I don't know why dark matter would make the cosmic background cooler than usual, but people have looked for its imprint in the fluctuations found in the cosmic background (places where the fluctuations are denser than usual due to its clumping). That's one of the lines of evidence in its favor, actually.
Rather than saying "random", I prefer to say "not obvious" - that is, the "extra" gravity from Earth (just as an example) isn't necessarily projecting an Earth sized blob of gravity (or Earth * 10^36 sized blob) at one other point in space. More that much smaller parts of Earth are projecting much smaller blobs of gravity at various locations.
I don't see how you're going to get an effective central force out of that without a lot of fine tuning. And I don't know what mechanism is supposed to hook local portions of space up to distant locations in any manner other than random. At least in quantum cosmology you could imagine some kind of chaotic spacetime foam.
Who's to say we'd see "huge" apparent violations?
If dark matter is affecting galactic dynamics so strongly that we have to postulate that 90% of the matter out there is dark matter, I can't see how you're going to avoid strong violations.
It is theoretically testable though
I don't know. It's impossible to prove vague theories wrong. To make predictions that are really testable, you need to embed it in a quantitative framework, like a gravitational field theory.
You really have no clue how science works, do you?
Dark matter is not some ad hoc "explanation". There are good reasons to believe it exists entirely independent of astrophysics, as I mentioned. Beyond that, it explains a number of very different astrophysical phenomena in a consistent way. Most other explanations fall short; they can explain one gravitational anomaly but are silent on or often inconsistent with others. Furthermore, dark matter is not a unfalsifiable band-aid that can explain anything; it makes very specific predictions about what we should see, and indeed several specific dark matter theories (such as massive compact halo objects) have later failed new tests. Weakly interacting massive particles passed them, and are the only theory to have passed all of them.
Research like this makes a number of assumptions about "Dark Matter," for instance that it exists at all
Yeah, duh. That's how you do science. Propose a hypothesis, see what it predicts if you assume it's true, and see if that prediction holds in the real world.
I think the biggest assumption is that "Dark Matter" is actually some kind of particle.
How is that a big assumption? It explains the observations easily, most leading theories of particle physics predict such a particle for independent reasons, similar particles (though lighter) are known to exist already, and competing assumptions (brown dwarfs or other compact bodies, modified gravity, etc.) fail to explain the observations.
I was simply giving two somewhat separate ideas with a related core idea - that of the twisted dimensions allowing for distant objects to be in reality "right beside each other"
Okay, ignore for the moment quantum mechanics and just talk extra dimensions. It's still really hard to explain dark matter by appealing to distant normal matter being nearby in extra dimensions. Think about how these dimensions need to be connected. The standard scenario has them curled up small, which means that matter only interacts with itself through them, not with distant matter. Or you could postulate that they hook up to distant parts of the universe, but doesn't explain how galaxies consistently get connected to other collections of matter. Even if they did, that doesn't explain a gravitational force that acts like dark matter does; it would probably be more like putting two galaxies on top of each other. Or you could also postulate that matter is connected up randomly with other matter, but with that it would hard to explain any consistent attractive effective force, let alone one that is attractive in the manner required. And then I suspect that you would see huge apparent violations in conservation of energy if there are significant interactions going on in unseen extra dimensions. Finally, I can't think of any actual theory within which you could construct any of these scenarios with any plausibility.
The usual extra dimensional gravity scenarios are (a) gravitational interactions between matter and itself in extra dimensions ("large extra dimensions"), and (b) interactions beteween matter in our universe and matter in a "parallel universe next to ours" (e.g., "braneworlds"). I think dark matter scenarios have been proposed in both, but I think they both have problems and they're even more speculative than dark matter is.
The Standard Model arguably includes axions, which were postulated to solve the strong-CP problem in quantum chromodynamics. They are dark matter candidates (although I think astrophysical constrains favor SUSY.) However, like the Higgs boson, they have not yet been observed.
Dark matter is matter that doesn't interact electromagnetically (or does so very weakly). It can interact by any other interaction other than electromagnetism, including but not limited to gravity.
The blind dedication to the dark matter cause seems superfluous to the realisation that our local models of physics don't scale galacticaly.
There is no "blind dedication to dark matter". And in fact, not scaling properly is exactly what's wrong with MOND. If you apply it to galaxies, it doesn't work for cosmology, and so on.
That's not a personal theory, that's a real theory: redshift is affected by gravity. (Google "gravitational redshift".) The explanation of cosmological redshift can be interpreted that way (expanding universe implies curved spacetime which implies gravitational redshift). But you can't explain cosmological redshift using a non-expanding flat universe by appealing to galaxies' gravity alone. It doesn't explain the distance-redshift relation, the luminosity-redshift relation, it would show a strong correlation with galactic/stellar mass which is absent in the data, and so on.
Say with MOND, why are we so scared to think that perhaps Newtonian mechanics aren't quite enough to calculate with on galactic scales? Why do they think MOND is for cranks and crackpots?
Who's this "they"? There is a really unpleasant meme running around Slashdot that reactionary scientists scorn and mock anything that isn't mainstream. In reality, MOND is not a mainstream theory (and for good reason), but it's still discussed seriously. Google around for Sean Carroll's presentation a year or two ago on MOND vs. dark matter (can't remember when that was when he was at U. Chicago or Caltech). This is a good summary of his for why dark matter is likely to exist.
What of a static non-expanding universe and alternate redshift paradigms? Are they not just as feasible as exotic matter that only interacts gravitationally?
No, not even remotely. They are vastly less plausible than even MOND, which has problems of its own. But since this is about dark matter and its competitors, I'll stick to those.
I'm just curious as to why dark matter is so widely supported, is it merely because breaking the standard model makes physicists too uncomfortable?
Yeah, it's because theoretical physicists hate new theories. No theoretical physicist ever got fame and tenure by coming up with a new theory. They gotta stick to the old ones to survive.
Seriously, tone down the paranoia. Dark matter also breaks the Standard Model by introducing new kinds of particles. (Well, unless you think it's axions, which are arguably part of the Standard Model). It's not like nobody has ever thought of an alternative gravity theory before. You can carpet a small moon with all the alternative gravity theories out there; scalar-tensor gravity, vector-tensor gravity, conformal gravity, chiral gravity, supergravity, and so on.
The simple facts are that it's really hard to muck around with gravity in a way that simultaneously agrees with observations on tabletop, stellar, planetary system, galactic, and cosmological scales. With MOND it's easy to reproduce galactic rotation curves, but not much else. MOND also contradicts relativity; it's strictly Newtonian. There has been an attempt to correct that in the form of TeVeS (tensor-vector-scalar gravity). But TeVeS requires you to introduce two new gravitational fields, plus couple them together in just the right way, and even then it's far from certain whether it can explain dark matter evidence on all different scales (galaxies, clusters, cosmology, etc.). Furthermore MOND has difficulty explaining rather direct evidence of dark matter like the Bullet Cluster. Even if MOND is correct, it seems likely that you still need dark matter to explain everything.
After all that, MOND looks far more ad hoc than just postulating the existence of a new kind of particle, especially since most of the new particle theories out there predict some kind of dark-matter like particle anyway for completely independent reasons. It's not like weakly interacting particles are terribly bizarre in the first place; neutrinos are dark matter, although they're too light to be most of the dark matter. The main difference between most of the dark matter and neutrinos is mass, and what's so odd something weak like a neutrino, only heavier? Such a particle, predicted by many theories, can (unlike MOND) simultaneously explain all the astrophysical phenomena which point towards dark matter.
Other than the large amount of seemingly "dark matter"...
There's nothing non-classical (i.e., quantum) about the behavior of dark matter. At least nothing we've observed so far. It's just matter, maybe like a neutrino but heavier. You don't need to appeal to quantum entanglement or anything exotic to explain it.
If we have a pair of entangled particles, they can THEN be separated by (apparently) quite any distance in classical space and nevertheless remain entangled.
In theory, yes. In practice, they need to be extremely isolated from everything else in the universe to remain entangled. That's why it's so difficult to maintain long-range entanglement for purposes like quantum encryption. You may think space is "empty", but it just takes a single photon to ruin the entanglement.
This is why my hypothesis considers that they may actually not be physically separate at all - they are "right beside each other" through twisted "extra" dimensions, just in some way that we currently do not have the ability to measure or understand particularly well.
Now you're mixing up two different ideas, quantum mechanics and extra dimensions. If they're interacting through other dimensions, fine, but you don't need entanglement to explain that either.
This leads on to the idea of "dark matter" being gravity from "nearby" objects that are classically quite distant, but in reality quite "close".
All the above problems notwithstanding, it's easy to come up with more. Even if you ignore the fact that these particles can't plausibly remain entangled, you have to explain how all these distant particles got entangled with each other in the first place. (If you're tempted to say "the Big Bang", you really can't ignore the previous fact given the extreme temperatures involved. Maintaining entanglement requires no outside interaction with other particles at any time over the intervening 14 billion years.) Furthermore, entangled particles interact with each other, but that interaction in general doesn't look anything like the vector or tensor field theories that give rise to what we think of as "forces" such as gravity or electromagnetism. (Why should this purported "entanglement force" act like gravity anyway?) And there's no explanation for the astrophysical observations like how entanglement with distant particles can simulate the effects of a spherical cloud of dark matter enclosing a disc galaxy.
Basically, it seems like a very bizarre hypotheses that, all the physical evidence against it aside, doesn't even seem to have much to commend it over the alternatives. It's not like the idea of there being weakly interacting particles out there is so crazy; plenty of particle theories predict them for completely independent reasons including possibly the Standard Model, and there are other weakly interacting (though less massive) particles out there already, like neutrinos.
The main problem with your theory is that entanglement just isn't that relevant on cosmological scales. On large scales, physics is pretty classical and entanglement irrelevant. That can change at small scales, so you might argue that it used to be relevant (near the Big Bang). But then temperature screws everything up: thermal excitation screws up the entanglement. Maybe it could have been relevant right at the Big Bang itself, due to poorly understood quantum gravity, but it has little to do with any macroscopic physics going on today. That's why the world around us looks classical and it took so long to discover quantum mechanics.
CO2 is generally a Good Thing as far as biological processes go.
It's good for some plants, up to a point. (C3 photosynthesizers like it; C4 plants are indifferent.) Animals don't care much about CO2 unless it reaches poisonous levels. Even the C3 plants don't get much of a boost past a certain point, because other factors end up being rate limiting (e.g., water and nitrogen availability).
What makes you think that life with previous high levels of this trace gas would be unpleasant for human beings?
Because modern societies have been adapted to a certain kind of climate and it's expensive to have to adapt to another climate in a relatively short period of time. It's not that we can't do it, it just has costs associated with it which are probably higher than the costs of avoiding the worst change.
Your CO2 positive feedback loop argument doesn't hold water because we know that CO2 levels were higher in the past and yet the Earth did not turn into Venus and we still had ice ages afterwards.
A positive feedback loop doesn't have to persist forever. Most of them don't. (Same as with water vapor feedback; we don't warm until we evaporate the oceans in a "runaway greenhouse", just to a new equilibrium, unless we pass a certain threshold.)
With CO2 feedback, CO2 that comes out of the ocean (or more often, CO2 that is less strongly absorbed by the ocean sink) stabilizes as the oceans reach a new equilibrium temperature. It's not like some tiny temperature change causes it all to outgas from solution in a runaway explosion of CO2. It's basic chemistry.
Furthermore, the very ice ages you appeal to are evidence of this: the insolation and albedo changes associated with the ice age cycle are too small to account for the observed temperature changes, if you leave out the amplification of the CO2 greenhouse effect.
The other problem is that the argument that CO2 increases can cause the temperature to rise significantly has not been substantiated experimentally. Even theoretically, there is no "from the ground up" explanation (i.e., devoid of handwaving) of how this should actually happen.
That's a ridiculous statement. The spectral adsorption of infrared radiation by CO2 is well studied in the laboratory and is observed in the real atmosphere. In the atmosphere it's modified by convective effects, which require line-by-line radiative transfer codes to calculate, but that doesn't change the basic fact that less energy is escaping to space, and it doesn't mean there is no explanation of how the greenhouse effect happens. Indeed, one of the main signatures of the greenhouse effect (stratospheric cooling) is observed in the atmosphere.
The existence of the greenhouse effect is not scientifically controversial even among the skeptics. You need to catch up with the skeptical literature. The argument is about whether the CO2 greenhouse effect is amplified by a lot or by a little due to other feedbacks (the climate sensitivity).
Saying temperatures are rising much faster than we should be suggests you're buying into the now comprehensively debunked hockey stick reconstruction.
No, you don't have to appeal to millennial-scale paleoclimate to conclude that; you can conclude it from modern instrumental records of climate and its natural drivers.
First, your original post suggested that some of the warming is explained by the fact that we're coming out of an ice age. Strictly speaking, this is incorrect: we came out of an ice age 10,000 years ago, and we generally cool after that, not warm.
What you probably mean is that we were coming out of the so-called "Little Ice Age" (not a true ice age), which is correct. However, we are still warming faster than can be explained by that, just on the basis of the natural causes of climate change. The LIA is attributed mostly to a reduction in solar irradia
What is debated by scientists is if man is responsible.
No, that's not really debated by scientists very much any more. Just read the latest issues of Nature Geoscience, Journal of Climate, Geophysical Reseearch Letters, etc. What's debated by scientists is how much climate change man is going to cause in the future.
Why is Mars also experiencing warming globally?
That has got to be the worst argument in favor of natural Earth warming ever. The Earth's climate has been intensively studied directly, but you want to throw out all those conclusions in favor of much sparser and less well understood data on another planet — one with no oceans, no biosphere, barely no atmosphere, and a totally different topography — and expect to draw conclusions about Earth climate?
The only climate link that the Earth and Mars share is the Sun, but solar output fails to explain warming on both planets, as it has not appreciably increased when the warming was observed.
But since you ask, the recent temperature fluctuations on Mars are currently attributed to natural seasonal variability and dust storms.
Why did the temperature go up THEN CO2 levels rise, rather then the opposite if CO2 is the cause?
That's true of the ice age cycle, but isn't true of all past warmings (e.g., the Paleocene-Eocene Thermal Maximum, where a large carbon excursion was followed by a large temperature change). As for the ice age cycle, the idea is that temperature changes affect the oceanic and terrestrial carbon cycles, which release carbon, which in turn adds to the temperature change. The known glacial-interglacial temperature change is too large to be explained without including the greenhouse effect of this additional CO2. (Insolation alone is too small although that probably kicks off the whole feedback loop; albedo change is significant but definitely not large enough, etc.) When CO2 is included, you approximately the right magnitude.
My suggestion would be to gain a better understanding of how our global environment and global climate function and self-regulate before we make concerted efforts to modify either.
That's not a very good policy. "Do nothing until we learn more" only works when we're likely to learn a great deal, in a short time, and that what we learn is likely to reveal that climate change is far less serious than we thought. Since we learn only slowly about the climate, and we have no way of knowing whether it's going to end up being better or worse than we currently think, the best policy is to start mitigation now and adjust it up or down if and when we learn more. Actually, it's even possible that our uncertainty about climate will increase with time (our ability to model the climate improves but we also discover new uncertainties and begin to be able to treat old ones which were ignored), which argues even more strongly in favor of abatement as an insurance policy. The less we know, the less willing we should be to move away from a known safe climate.
As it stands, it's still widely debated whether our actions to date have had much of any effect on the environment, or whether we're seeing natural patterns and cycles in motion, or whether we're seeing events triggered by unknown influences.
No, it's really not that widely debated, among the scientific community. Just peruse the latest issues of Nature Geosciences, Journal of Climate, Geophysical Research Letters, etc.
Where we get lost is in figuring out how a factory in Beijing affects a farm in Kansas. Some have said it will cause less rain; some have said it will cause more. Some have said it will cause both. Some have said it will cause temperatures to drop, more now lean toward them climbing.
That depends on the region. We can't predict regional impacts very well, although we can do decently for broad latitudinal bands. We do know that global warming will, on the balance, tend to lead to higher temperatures worldwide (more over land than ocean, more in the Northern Hemisphere than Southern, and more near the Arctic than away from it). There will be somewhat higher precipitation, but the rain zones will shift so some will get more rain and some will get more drought, and both will experience different precipitation patterns than they're used to; there will also likely be an increase in extremes (both downpours and drought) even when precipitation as a whole goes up.
In other words, we have no understanding of what effects we're having (if anything) on the world's climate, and we have no idea if we're headed in the direction.
No. We have a pretty good idea of what effects we've had so far, and we have some idea of what effects we will have in the future. We can, for instance, rule out "less than 1 degree of warming by 2100", and "more than several meters of sea rise by 2100" with high (not perfect) probability. That alone is enough to greatly inform the policy decision, and we actually know more than that.
We have no idea if there's an outside influence causing the slight change in temperatures we've observed over the past ~80 years of decent weather tracking.
Yes, we do. There aren't that many plausible candidates for that amount of warming (which isn't really as slight as you think on an 80 year time scale): greenhouse gases, solar irradiance, volcanism, industrial aerosols, atmosphere-ocean heat exchange. All of those have been looked at in great detail.
Furthermore, you're still missing the point about uncertainty in decision making. A do-nothing policy is only justified when we're CERTAIN that the problem will be minimal. An insurance policy of abatement is what you do when you're UNCERTAIN.
So what I would suggest for now, rather than blow our economies trying to force some nations (ie the US) to finance some huge operatio
Wow, you totally don't know economics do you? A Pigovian tax is a classic example of a market based incentive for pollution control. You've probably bought the neo-conservative line that taxes are antithetic to the free market. On the contrary, if you have a negative externality (like the market being unaware of the environmental costs of CO2), the market-based way of doing that is to get rid of the externality by putting a price on it. A tax is one of the textbook ways to provide the market with the necessary financial incentive.
Indeed, a carbon tax is believed by perhaps most economists to get the job done at a lower cost than carbon permit trading, in addition to being simpler to implement, more predictable for planning, and harder to cheat. See the literature on price vs. quantity instruments; for the seminal introduction see Weitzman (1974), and for application to climate change see Pizer (1997), and check out the Pigou Club. Note that Pigovian taxes aren't synonymous with "the government gets more money"; the carbon taxes people talk about are often revenue-neutral (either through tax shifting or dividends).
Slashdot Mirror
This is the kind oftedious, petulant ad hominem routine that makes dealing with pro-AGW individuals so different from any other scientific debate.
Ha! You don't read Slashdot much, do you? Go read any of the threads on evolution, the electric universe, string theory, dark matter, ...
And give me a break with the moral high horse. You're the one who ended with an insulting parting shot about how people don't critically evaluate climate science and how they're "alarmists". I didn't drop any snide remarks about "denialists" who are in the back pocket of Exxon, or anything similarly odious.
But while we're on the topic, what makes dealing with anti-AGW self-professed "skeptics" so tedious is that they tend to get all their science from skeptic websites instead of actual scientific literature. And then, unlike honest skeptics, they go out and misinform the public based on their distorted pseudo-education. I was hoping it would sink in that you're serving as a great example of what's wrong with the climate science debate, but you don't seem to have noticed.
Can we at least agree that we are not in danger of increasing CO2 levels to poisonous levels?
Sure, but since no one has claimed we are, it's irrelevant.
Society seems to have adapted rather well to a climate that was already changing (about half the warming this century seems to have happened between 1940 and 1970, and it didn't seem to bother anybody).
To the contrary, the economic damage assessments are based in part on historical records of temperature/precipitation effects on agriculture and other sectors of the economy. The global effects have been relatively small so far, since the climate change has not yet been that large, but they're not negligible either. And it's questionable at best to conclude that the impacts of climate are negligible, when the future climate change can be 4x larger than in the last century (and even larger than the change in the 1940-1970 period you mention).
Bjorn Lomborg's Copenhagen Concensus of eight world class economists started from the assumption that the IPCC's claims for future warming are reasonable and *still* concluded after a costs-benefits analysis that dealing with climate change via economic measures was a bad idea (climate change came in bottom of the list, after fourteen other proposals for improving the state of the world).
Have you read their report? Or did you just read the skeptic spin?
They didn't conclude that dealing with climate change via economic measures was a bad idea. They only said there were other things they thought should be dealt with via economic measures too, and some of them get a higher return on investment. The Copenhagen analysis is structured only to answer the question, "If we could spend money on just one thing, what would it be?" In reality, you need to spend money on all these problems. Just because you get more bang for your buck for one of them doesn't mean that you should ignore all the rest. And their analysis sometimes ignores the effect climate change has on the other problems they considered, e.g., they look at malaria but not on the climatic influences on that problem. (Or at least that's what I gathered from the challenge pieces; I never got around to reading all the supplementary perspective pieces.)
What they actually concluded is that dealing with climate change using pure mitigation is economically sub-optimal. They said that the optimal policy should include a combination of mitigation, adaptation, and technology R&D. Which is pretty much what anybody sensible says. And their optimal policy which includes CO2 mitigation as well as R&D leads to emissions in 2100 which are less than half of what the optimal policy would be if you ignored mitigation and relied only on technology improvements.
The Copenhagen Consensus did not claim that climate cha
Ok, name one "huge protest" over direct advertising that has gone unreported in the media.
You must live in a very different U.S. than I do. In the U.S. I'm familiar with, there have not been any "huge protests" over newspapers publishing photos of criminal suspects, having trouble renting a hotel room in cash, direct advertising, or any of the other examples the parent poster was referring to.
Everybody I have ever had a conversation with, in person, is as outraged and disturbed as you are by the erosion of privacy. [...] I would state 100,000% that ONLY companies and various organizations get represented in US government today. [...] The America you are talking about is not one that was created by the people. It was created over the protest of Americans every single step of the way.
Yeah right. Most Americans don't think about and don't care about these issues. Yeah, if you have a conversation with one they'd probably say they don't like it. Maybe they'd even be "outraged". But would that make them protest or otherwise take political action? Keep them up at night? Or even make them think much about it later? No. Not beyond a tiny minority that is over-represented here on Slashdot.
The America being spoken of was not created by corporations, but by public apathy.
We actually have a better chance of detecting the exotic particles than the rogue planets, so some people are focusing on that
It's the other way around. Dark matter in the form of brown dwarves and such has actually been detected through gravitational microlensing observations. That's how we know that most of the dark matter isn't brown dwarves and other compact astrophysical bodies; it's there, but there isn't enough of it to explain the necessary gravitational effects.
Plenty of dark matter theories have already been falsified. The majority of dark matter isn't brown dwarves, black holes, or neutrinos. The whole "hot" vs. "warm" vs. "cold" dark matter debate ended up ruling out slews of candidate particles. Many of the proposed candidates have the wrong mass. Others interact with other particles in the early universe and screw up structure formation. Some are excluded by direct searches in dark matter detectors. And so on.
And the Flying Spaghetti Monster theory passes all of them with flying colors as well.
So, no, you don't understand how science works.
The FSM isn't falsifiable, it doesn't make any specific quantitative predictions, its existence is not a natural consequence of other physical theories.
It's silly science to be saying "Dark Matter does it!" when there is literally no evidence that this nebulous "Dark Matter" even exists.
Think for a minute.
If a weakly interacting massive particle existed, what evidence would we see that it exists?
Gravitational anomalies of a very specific quantitative character on scales from galaxies to clusters to cosmology. These anomalies would not be totally independent but would relate to each other in a specific quantitative way linked by the mass of the particle. This is what we actually do see. Furthermore, the existence of these particles has been independently predicted to explain non-gravitational phenomena in elementary particle physics.
These "very specific predictions" are manufactured by scientists trying to explain the unexplainable,
Yes, we get it, you don't understand and don't like science. The fact remains is that dark matter has passed every observational test we've thrown at it, it's extremely unlikely that a random theory would pass all those tests by coincidence, the alternative theories have failed, and we have good independent reasons to believe such particles exist even if we'd never turned a telescope to the sky.
I'm a physicist too. Please stop embarrassing us. Your personal dislike for the theory is sadly irrelevant to the evidence in its favor.
Dark matter probably collides with the Earth all the time and we don't notice since it interacts so weakly with us. It's the same with neutrinos. I don't know why dark matter would make the cosmic background cooler than usual, but people have looked for its imprint in the fluctuations found in the cosmic background (places where the fluctuations are denser than usual due to its clumping). That's one of the lines of evidence in its favor, actually.
Rather than saying "random", I prefer to say "not obvious" - that is, the "extra" gravity from Earth (just as an example) isn't necessarily projecting an Earth sized blob of gravity (or Earth * 10^36 sized blob) at one other point in space. More that much smaller parts of Earth are projecting much smaller blobs of gravity at various locations.
I don't see how you're going to get an effective central force out of that without a lot of fine tuning. And I don't know what mechanism is supposed to hook local portions of space up to distant locations in any manner other than random. At least in quantum cosmology you could imagine some kind of chaotic spacetime foam.
Who's to say we'd see "huge" apparent violations?
If dark matter is affecting galactic dynamics so strongly that we have to postulate that 90% of the matter out there is dark matter, I can't see how you're going to avoid strong violations.
It is theoretically testable though
I don't know. It's impossible to prove vague theories wrong. To make predictions that are really testable, you need to embed it in a quantitative framework, like a gravitational field theory.
You really have no clue how science works, do you?
Dark matter is not some ad hoc "explanation". There are good reasons to believe it exists entirely independent of astrophysics, as I mentioned. Beyond that, it explains a number of very different astrophysical phenomena in a consistent way. Most other explanations fall short; they can explain one gravitational anomaly but are silent on or often inconsistent with others. Furthermore, dark matter is not a unfalsifiable band-aid that can explain anything; it makes very specific predictions about what we should see, and indeed several specific dark matter theories (such as massive compact halo objects) have later failed new tests. Weakly interacting massive particles passed them, and are the only theory to have passed all of them.
Research like this makes a number of assumptions about "Dark Matter," for instance that it exists at all
Yeah, duh. That's how you do science. Propose a hypothesis, see what it predicts if you assume it's true, and see if that prediction holds in the real world.
I think the biggest assumption is that "Dark Matter" is actually some kind of particle.
How is that a big assumption? It explains the observations easily, most leading theories of particle physics predict such a particle for independent reasons, similar particles (though lighter) are known to exist already, and competing assumptions (brown dwarfs or other compact bodies, modified gravity, etc.) fail to explain the observations.
I was simply giving two somewhat separate ideas with a related core idea - that of the twisted dimensions allowing for distant objects to be in reality "right beside each other"
Okay, ignore for the moment quantum mechanics and just talk extra dimensions. It's still really hard to explain dark matter by appealing to distant normal matter being nearby in extra dimensions. Think about how these dimensions need to be connected. The standard scenario has them curled up small, which means that matter only interacts with itself through them, not with distant matter. Or you could postulate that they hook up to distant parts of the universe, but doesn't explain how galaxies consistently get connected to other collections of matter. Even if they did, that doesn't explain a gravitational force that acts like dark matter does; it would probably be more like putting two galaxies on top of each other. Or you could also postulate that matter is connected up randomly with other matter, but with that it would hard to explain any consistent attractive effective force, let alone one that is attractive in the manner required. And then I suspect that you would see huge apparent violations in conservation of energy if there are significant interactions going on in unseen extra dimensions. Finally, I can't think of any actual theory within which you could construct any of these scenarios with any plausibility.
The usual extra dimensional gravity scenarios are (a) gravitational interactions between matter and itself in extra dimensions ("large extra dimensions"), and (b) interactions beteween matter in our universe and matter in a "parallel universe next to ours" (e.g., "braneworlds"). I think dark matter scenarios have been proposed in both, but I think they both have problems and they're even more speculative than dark matter is.
The Standard Model arguably includes axions, which were postulated to solve the strong-CP problem in quantum chromodynamics. They are dark matter candidates (although I think astrophysical constrains favor SUSY.) However, like the Higgs boson, they have not yet been observed.
Yes, they're reliable enough for policy recommendations. What's your point?
Dark matter is matter that doesn't interact electromagnetically (or does so very weakly). It can interact by any other interaction other than electromagnetism, including but not limited to gravity.
The blind dedication to the dark matter cause seems superfluous to the realisation that our local models of physics don't scale galacticaly.
There is no "blind dedication to dark matter". And in fact, not scaling properly is exactly what's wrong with MOND. If you apply it to galaxies, it doesn't work for cosmology, and so on.
That's not a personal theory, that's a real theory: redshift is affected by gravity. (Google "gravitational redshift".) The explanation of cosmological redshift can be interpreted that way (expanding universe implies curved spacetime which implies gravitational redshift). But you can't explain cosmological redshift using a non-expanding flat universe by appealing to galaxies' gravity alone. It doesn't explain the distance-redshift relation, the luminosity-redshift relation, it would show a strong correlation with galactic/stellar mass which is absent in the data, and so on.
Say with MOND, why are we so scared to think that perhaps Newtonian mechanics aren't quite enough to calculate with on galactic scales? Why do they think MOND is for cranks and crackpots?
Who's this "they"? There is a really unpleasant meme running around Slashdot that reactionary scientists scorn and mock anything that isn't mainstream. In reality, MOND is not a mainstream theory (and for good reason), but it's still discussed seriously. Google around for Sean Carroll's presentation a year or two ago on MOND vs. dark matter (can't remember when that was when he was at U. Chicago or Caltech). This is a good summary of his for why dark matter is likely to exist.
What of a static non-expanding universe and alternate redshift paradigms? Are they not just as feasible as exotic matter that only interacts gravitationally?
No, not even remotely. They are vastly less plausible than even MOND, which has problems of its own. But since this is about dark matter and its competitors, I'll stick to those.
I'm just curious as to why dark matter is so widely supported, is it merely because breaking the standard model makes physicists too uncomfortable?
Yeah, it's because theoretical physicists hate new theories. No theoretical physicist ever got fame and tenure by coming up with a new theory. They gotta stick to the old ones to survive.
Seriously, tone down the paranoia. Dark matter also breaks the Standard Model by introducing new kinds of particles. (Well, unless you think it's axions, which are arguably part of the Standard Model). It's not like nobody has ever thought of an alternative gravity theory before. You can carpet a small moon with all the alternative gravity theories out there; scalar-tensor gravity, vector-tensor gravity, conformal gravity, chiral gravity, supergravity, and so on.
The simple facts are that it's really hard to muck around with gravity in a way that simultaneously agrees with observations on tabletop, stellar, planetary system, galactic, and cosmological scales. With MOND it's easy to reproduce galactic rotation curves, but not much else. MOND also contradicts relativity; it's strictly Newtonian. There has been an attempt to correct that in the form of TeVeS (tensor-vector-scalar gravity). But TeVeS requires you to introduce two new gravitational fields, plus couple them together in just the right way, and even then it's far from certain whether it can explain dark matter evidence on all different scales (galaxies, clusters, cosmology, etc.). Furthermore MOND has difficulty explaining rather direct evidence of dark matter like the Bullet Cluster. Even if MOND is correct, it seems likely that you still need dark matter to explain everything.
After all that, MOND looks far more ad hoc than just postulating the existence of a new kind of particle, especially since most of the new particle theories out there predict some kind of dark-matter like particle anyway for completely independent reasons. It's not like weakly interacting particles are terribly bizarre in the first place; neutrinos are dark matter, although they're too light to be most of the dark matter. The main difference between most of the dark matter and neutrinos is mass, and what's so odd something weak like a neutrino, only heavier? Such a particle, predicted by many theories, can (unlike MOND) simultaneously explain all the astrophysical phenomena which point towards dark matter.
Other than the large amount of seemingly "dark matter"...
There's nothing non-classical (i.e., quantum) about the behavior of dark matter. At least nothing we've observed so far. It's just matter, maybe like a neutrino but heavier. You don't need to appeal to quantum entanglement or anything exotic to explain it.
If we have a pair of entangled particles, they can THEN be separated by (apparently) quite any distance in classical space and nevertheless remain entangled.
In theory, yes. In practice, they need to be extremely isolated from everything else in the universe to remain entangled. That's why it's so difficult to maintain long-range entanglement for purposes like quantum encryption. You may think space is "empty", but it just takes a single photon to ruin the entanglement.
This is why my hypothesis considers that they may actually not be physically separate at all - they are "right beside each other" through twisted "extra" dimensions, just in some way that we currently do not have the ability to measure or understand particularly well.
Now you're mixing up two different ideas, quantum mechanics and extra dimensions. If they're interacting through other dimensions, fine, but you don't need entanglement to explain that either.
This leads on to the idea of "dark matter" being gravity from "nearby" objects that are classically quite distant, but in reality quite "close".
All the above problems notwithstanding, it's easy to come up with more. Even if you ignore the fact that these particles can't plausibly remain entangled, you have to explain how all these distant particles got entangled with each other in the first place. (If you're tempted to say "the Big Bang", you really can't ignore the previous fact given the extreme temperatures involved. Maintaining entanglement requires no outside interaction with other particles at any time over the intervening 14 billion years.) Furthermore, entangled particles interact with each other, but that interaction in general doesn't look anything like the vector or tensor field theories that give rise to what we think of as "forces" such as gravity or electromagnetism. (Why should this purported "entanglement force" act like gravity anyway?) And there's no explanation for the astrophysical observations like how entanglement with distant particles can simulate the effects of a spherical cloud of dark matter enclosing a disc galaxy.
Basically, it seems like a very bizarre hypotheses that, all the physical evidence against it aside, doesn't even seem to have much to commend it over the alternatives. It's not like the idea of there being weakly interacting particles out there is so crazy; plenty of particle theories predict them for completely independent reasons including possibly the Standard Model, and there are other weakly interacting (though less massive) particles out there already, like neutrinos.
The main problem with your theory is that entanglement just isn't that relevant on cosmological scales. On large scales, physics is pretty classical and entanglement irrelevant. That can change at small scales, so you might argue that it used to be relevant (near the Big Bang). But then temperature screws everything up: thermal excitation screws up the entanglement. Maybe it could have been relevant right at the Big Bang itself, due to poorly understood quantum gravity, but it has little to do with any macroscopic physics going on today. That's why the world around us looks classical and it took so long to discover quantum mechanics.
CO2 is generally a Good Thing as far as biological processes go.
It's good for some plants, up to a point. (C3 photosynthesizers like it; C4 plants are indifferent.) Animals don't care much about CO2 unless it reaches poisonous levels. Even the C3 plants don't get much of a boost past a certain point, because other factors end up being rate limiting (e.g., water and nitrogen availability).
What makes you think that life with previous high levels of this trace gas would be unpleasant for human beings?
Because modern societies have been adapted to a certain kind of climate and it's expensive to have to adapt to another climate in a relatively short period of time. It's not that we can't do it, it just has costs associated with it which are probably higher than the costs of avoiding the worst change.
Your CO2 positive feedback loop argument doesn't hold water because we know that CO2 levels were higher in the past and yet the Earth did not turn into Venus and we still had ice ages afterwards.
A positive feedback loop doesn't have to persist forever. Most of them don't. (Same as with water vapor feedback; we don't warm until we evaporate the oceans in a "runaway greenhouse", just to a new equilibrium, unless we pass a certain threshold.)
With CO2 feedback, CO2 that comes out of the ocean (or more often, CO2 that is less strongly absorbed by the ocean sink) stabilizes as the oceans reach a new equilibrium temperature. It's not like some tiny temperature change causes it all to outgas from solution in a runaway explosion of CO2. It's basic chemistry.
Furthermore, the very ice ages you appeal to are evidence of this: the insolation and albedo changes associated with the ice age cycle are too small to account for the observed temperature changes, if you leave out the amplification of the CO2 greenhouse effect.
The other problem is that the argument that CO2 increases can cause the temperature to rise significantly has not been substantiated experimentally. Even theoretically, there is no "from the ground up" explanation (i.e., devoid of handwaving) of how this should actually happen.
That's a ridiculous statement. The spectral adsorption of infrared radiation by CO2 is well studied in the laboratory and is observed in the real atmosphere. In the atmosphere it's modified by convective effects, which require line-by-line radiative transfer codes to calculate, but that doesn't change the basic fact that less energy is escaping to space, and it doesn't mean there is no explanation of how the greenhouse effect happens. Indeed, one of the main signatures of the greenhouse effect (stratospheric cooling) is observed in the atmosphere.
The existence of the greenhouse effect is not scientifically controversial even among the skeptics. You need to catch up with the skeptical literature. The argument is about whether the CO2 greenhouse effect is amplified by a lot or by a little due to other feedbacks (the climate sensitivity).
Saying temperatures are rising much faster than we should be suggests you're buying into the now comprehensively debunked hockey stick reconstruction.
No, you don't have to appeal to millennial-scale paleoclimate to conclude that; you can conclude it from modern instrumental records of climate and its natural drivers.
First, your original post suggested that some of the warming is explained by the fact that we're coming out of an ice age. Strictly speaking, this is incorrect: we came out of an ice age 10,000 years ago, and we generally cool after that, not warm.
What you probably mean is that we were coming out of the so-called "Little Ice Age" (not a true ice age), which is correct. However, we are still warming faster than can be explained by that, just on the basis of the natural causes of climate change. The LIA is attributed mostly to a reduction in solar irradia
What is debated by scientists is if man is responsible.
No, that's not really debated by scientists very much any more. Just read the latest issues of Nature Geoscience, Journal of Climate, Geophysical Reseearch Letters, etc. What's debated by scientists is how much climate change man is going to cause in the future.
Why is Mars also experiencing warming globally?
That has got to be the worst argument in favor of natural Earth warming ever. The Earth's climate has been intensively studied directly, but you want to throw out all those conclusions in favor of much sparser and less well understood data on another planet — one with no oceans, no biosphere, barely no atmosphere, and a totally different topography — and expect to draw conclusions about Earth climate?
The only climate link that the Earth and Mars share is the Sun, but solar output fails to explain warming on both planets, as it has not appreciably increased when the warming was observed.
But since you ask, the recent temperature fluctuations on Mars are currently attributed to natural seasonal variability and dust storms.
Why did the temperature go up THEN CO2 levels rise, rather then the opposite if CO2 is the cause?
That's true of the ice age cycle, but isn't true of all past warmings (e.g., the Paleocene-Eocene Thermal Maximum, where a large carbon excursion was followed by a large temperature change). As for the ice age cycle, the idea is that temperature changes affect the oceanic and terrestrial carbon cycles, which release carbon, which in turn adds to the temperature change. The known glacial-interglacial temperature change is too large to be explained without including the greenhouse effect of this additional CO2. (Insolation alone is too small although that probably kicks off the whole feedback loop; albedo change is significant but definitely not large enough, etc.) When CO2 is included, you approximately the right magnitude.
My suggestion would be to gain a better understanding of how our global environment and global climate function and self-regulate before we make concerted efforts to modify either.
That's not a very good policy. "Do nothing until we learn more" only works when we're likely to learn a great deal, in a short time, and that what we learn is likely to reveal that climate change is far less serious than we thought. Since we learn only slowly about the climate, and we have no way of knowing whether it's going to end up being better or worse than we currently think, the best policy is to start mitigation now and adjust it up or down if and when we learn more. Actually, it's even possible that our uncertainty about climate will increase with time (our ability to model the climate improves but we also discover new uncertainties and begin to be able to treat old ones which were ignored), which argues even more strongly in favor of abatement as an insurance policy. The less we know, the less willing we should be to move away from a known safe climate.
As it stands, it's still widely debated whether our actions to date have had much of any effect on the environment, or whether we're seeing natural patterns and cycles in motion, or whether we're seeing events triggered by unknown influences.
No, it's really not that widely debated, among the scientific community. Just peruse the latest issues of Nature Geosciences, Journal of Climate, Geophysical Research Letters, etc.
Where we get lost is in figuring out how a factory in Beijing affects a farm in Kansas. Some have said it will cause less rain; some have said it will cause more. Some have said it will cause both. Some have said it will cause temperatures to drop, more now lean toward them climbing.
That depends on the region. We can't predict regional impacts very well, although we can do decently for broad latitudinal bands. We do know that global warming will, on the balance, tend to lead to higher temperatures worldwide (more over land than ocean, more in the Northern Hemisphere than Southern, and more near the Arctic than away from it). There will be somewhat higher precipitation, but the rain zones will shift so some will get more rain and some will get more drought, and both will experience different precipitation patterns than they're used to; there will also likely be an increase in extremes (both downpours and drought) even when precipitation as a whole goes up.
In other words, we have no understanding of what effects we're having (if anything) on the world's climate, and we have no idea if we're headed in the direction.
No. We have a pretty good idea of what effects we've had so far, and we have some idea of what effects we will have in the future. We can, for instance, rule out "less than 1 degree of warming by 2100", and "more than several meters of sea rise by 2100" with high (not perfect) probability. That alone is enough to greatly inform the policy decision, and we actually know more than that.
We have no idea if there's an outside influence causing the slight change in temperatures we've observed over the past ~80 years of decent weather tracking.
Yes, we do. There aren't that many plausible candidates for that amount of warming (which isn't really as slight as you think on an 80 year time scale): greenhouse gases, solar irradiance, volcanism, industrial aerosols, atmosphere-ocean heat exchange. All of those have been looked at in great detail.
Furthermore, you're still missing the point about uncertainty in decision making. A do-nothing policy is only justified when we're CERTAIN that the problem will be minimal. An insurance policy of abatement is what you do when you're UNCERTAIN.
So what I would suggest for now, rather than blow our economies trying to force some nations (ie the US) to finance some huge operatio
Wow, you totally don't know economics do you? A Pigovian tax is a classic example of a market based incentive for pollution control. You've probably bought the neo-conservative line that taxes are antithetic to the free market. On the contrary, if you have a negative externality (like the market being unaware of the environmental costs of CO2), the market-based way of doing that is to get rid of the externality by putting a price on it. A tax is one of the textbook ways to provide the market with the necessary financial incentive.
Indeed, a carbon tax is believed by perhaps most economists to get the job done at a lower cost than carbon permit trading, in addition to being simpler to implement, more predictable for planning, and harder to cheat. See the literature on price vs. quantity instruments; for the seminal introduction see Weitzman (1974), and for application to climate change see Pizer (1997), and check out the Pigou Club. Note that Pigovian taxes aren't synonymous with "the government gets more money"; the carbon taxes people talk about are often revenue-neutral (either through tax shifting or dividends).