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Little Ice Age: It Was Not the Sun

vikingpower writes "The Little Ice Age, lasting from the end of the Middle Age into the 17th century, may very likely have been caused by the combined effects of four major volcanic eruptions and increased sunlight reflection by increasing sea ice, the so-called Albedo effect. ... The University of Boulder has a press release with maps and photographs. Bette Otto-Bliesner, one of the scientists behind the 'volcano + sea ice' thesis, fields an earnest warning against drawing conclusions too quickly from this research: 'I think people might look at the Little Ice Age and think that all we need to save us from rising temperatures are some volcanic eruptions or the geo-engineering equivalent [...] But when you see what happened when global temperatures dropped by just one degree and you look at current predictions of six or seven degree increases for the future, you realize how precarious things are for life as we know it.'"

26 of 375 comments (clear)

  1. Global Warming? Let the Intelligent Debate Begin! by Anonymous Coward · · Score: 5, Funny

    No doubt this item will produce reasoned, well mannered discourse in droves! Pop some popcorn, enjoy the highbrow debate!

  2. Re:We didn't really know how things worked before by angry+tapir · · Score: 4, Insightful

    It always astonishes me that on a geeky site like Slashdot with an audience that in theory puts such a high value on science, you get so many global warming denialists.

  3. Re:We didn't really know how things worked before by evanism · · Score: 5, Funny

    We deny that.

    --
    Just bought a new quantum computer, but I'm uncertain how it works.
  4. Re:We didn't really know how things worked before by Anonymous Coward · · Score: 5, Insightful

    > Shouldn't all science be questioned?

    Yes - intelligently questioned by people who are qualified to criticize it. And who "question" it by doing their own research, investigation, hypothesizing and testing... which is not the same as digging up spurious out-of-context quotes and raising biased, uninformed objections for political reasons.

  5. Re:We didn't really know how things worked before by Ironix · · Score: 5, Insightful

    There's a difference between questioning a theory based on evidence to the contrary and questioning it simply because it is controversial. One of the few other scientific theories that seems to enjoy this distinction is the theory of evolution. However, you'd be hard pressed to find as many slashdotters making the same argument against that theory.

    --
    Still #1 -- Lonely Gay Geek
  6. Maunder minimum was not the culprit [Re:Of course] by Geoffrey.landis · · Score: 5, Informative

    After 5 billion years, the sun is basically in steady state. I would not expect to see fluctuations over the type of timescales that human beings exist on....

    the sun is pretty steady, a middle-aged star, but there are still some small variations in solar intensity. The hypothesis was that the Little Ice Age was correlated with the solar "Maunder Minimum," a 75-year period during which the sun had no sunspots (and hence presumably was about 0.07% lower in brightness).

    What this work did was put a good date to the start of the Little Ice Age; using radiocarbon dating to determine when the plants killed by the advancing glaciers died... and the dating shows the Little Ice Age began well before the Maunder minimum. The Maunder minimum didn't cause it, very definitely.

    --
    http://www.geoffreylandis.com
  7. Re:We didn't really know how things worked before by dkleinsc · · Score: 5, Interesting

    There are at least 5 reasons I can think of for that phenomenon:
    1. Some are shills for by the majorly carbon-emitting industries. There's no reasoning with this group, because they aren't here to reason or discuss, they're here to do their job of sowing doubt about whether global warming is real. Similarly, there may be commenters who aren't paid PR people, but work for these companies (e.g. a friend of mine who does geology on oil rigs for a living), for whom the "It is difficult to get a man to understand something when his salary depends on not understanding it" truly applies.

    2. Some believe that placing a high value on science involves being skeptical of anything not definitively proven. With anthropogenic global warming, because there's only 1 planet Earth (that I'm aware of) there's no way to definitely prove things one way or the other. This is true even if the vast majority of the research supports the theory that AGW is causing significant changes to the climate of the Earth.

    3. Some are politically libertarian and tend to strongly oppose government action not concerned with enforcing contracts, protecting property rights, or preventing violent attack and/or sexual assault on a citizen. If AGW is true, and private enterprise can't or won't act to stop it, then stopping it requires significant government intervention in the markets, which dismantles the idea that libertarianism can solve all human problems. It's not dramatically different from a reaction you might get to a devout born-again Christian discovering definitive proof that Jesus never existed.

    4. Some are unwilling to make the dramatic changes to everyday life that would be needed to reduce CO2 emissions in the short term. It would mean changes like having to move your home so you can commute to work without driving 30 miles, or having to put your washing machine on timers so the load runs at 3 AM rather than right now, or keeping your home at 55 F in the winter rather than the 70 F you find comfortable. Nobody wants to do that if they can think of a short-term alternative. This also manifests itself in an absolute faith that scientists and engineers will somehow come up with a solution that will solve the problem completely without requiring any kind of conservation effort.

    5. Environmentalists have been guilty of overstating their case in the past, so some are reluctant to believe anything they say.

    --
    I am officially gone from /. Long live http://www.soylentnews.com/
  8. Re:We didn't really know how things worked before by Daniel+Dvorkin · · Score: 5, Insightful

    One of the few other scientific theories that seems to enjoy this distinction is the theory of evolution. However, you'd be hard pressed to find as many slashdotters making the same argument against that theory.

    Actually, you will. Check any Slashdot story dealing with evolution, and you'll see a ton of comments pushing creationism (usually in its "intelligent design" guise) very often using the same "we should always question theories" argument. Sadly, almost none of these people seem willing to question the theory of gravity in the most obvious manner.

    --
    The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
  9. Re:We didn't really know how things worked before by causality · · Score: 4, Insightful

    > Shouldn't all science be questioned?

    Yes - intelligently questioned by people who are qualified to criticize it. And who "question" it by doing their own research, investigation, hypothesizing and testing... which is not the same as digging up spurious out-of-context quotes and raising biased, uninformed objections for political reasons.

    And yet if these unqualified non-scientists believed in said theory, you would have no quarrel with them. Even though they don't believe it as a result of being qualified, doing research, investigation, hypothesizing, and testing (redundant after "investigation"?).

    The unspoken, probably unacknowledged even by you, message here? "Don't question authority."

    I never believed that science was meant to be a priesthood. Back when we had priesthoods and considered that normal, don't we call those times the Dark Ages? The moment you are told that you're not qualified and therefore have no business forming your own position, that's the moment you have established a priesthood.

    I have an entirely different take. I think this science has a problem most sciences don't. We have only one planet that's practical to use for this model. We can't modify the system to test different variables in a rigorous way, and we can't compare what happens to a control group. There is too much uncertainty that there's no clear way to resolve. So, it becomes a political issue. It boils down to some authority's opinion concerning what makes the most sense. That's great fun when the authority is wrong, or there are multiple authorities who disagree with each other, or there's no positive way to rule those out.

    If you don't understand that, you wind up passionately judging the stupidity of people you know nothing about, not because they demonstrated stupidity but as a feeble attempt at shutting them up. After all, they followed the "wrong" authority. Do you realize that popular ideas which people were absolutely certain about, and sometimes would have fought and died over, that anyone would have been ridiculed for doubting, have turned out to be wrong in the past?

    --
    It is a miracle that curiosity survives formal education. - Einstein
  10. Re:We didn't really know how things worked before by ArcherB · · Score: 4, Insightful

    > Shouldn't all science be questioned?

    Yes - intelligently questioned by people who are qualified to criticize it. And who "question" it by doing their own research, investigation, hypothesizing and testing... which is not the same as digging up spurious out-of-context quotes and raising biased, uninformed objections for political reasons.

    See, that's the problem. Any scientist that questions it is immediately deemed unqualified or even unethical simply because they have bothered to question it.

    Can you name a me a single AGW "denialist" that you deem to be qualified enough to have their theories and research taken seriously?

    Exactly!

    --
    There is no "I disagree" mod for a reason. Flamebait, Troll, and Overrated are not substitutes.
  11. Re:We didn't really know how things worked before by mellon · · Score: 5, Insightful

    Yeah, computer models suck. That's why airplanes keep falling out of the sky, why missiles never hit their targets, and why you can never get the temperature of the brew head on your espresso machine just right. Er, wait, you can do all of these things. Because of computer models.

    Remember when the weather forecast was always wrong? It's been really remarkably precise recently when I've followed it, which I do a lot, because I enjoy outdoor sports. It's been scarily precise. Predictions a week out come true with astonishing regularity. This is weather, which is rapidly changing and chaotic, not climate, which is slow and relatively predictable.

    The problem with your completely ignorant assertion here is that in fact the models do appear to be getting more accurate, not less. The debates are not over whether there is warming, but over how much, and what the effect will be, and how soon the effect will come. Nobody is debating whether it's coming except people who are making a short-term killing on carbon externalities.

  12. Re:Maunder minimum was not the culprit [Re:Of cour by Fex303 · · Score: 4, Funny

    ... and the dating shows the Little Ice Age began well before the Maunder minimum. The Maunder minimum didn't cause it, very definitely.

    The only logical conclusion is that cold temperatures on earth somehow prevent sunspots. Which means, obviously, that global warming will blot out the sun due to a proliferation of sunspots caused by warmer temperatures here.

    We're doomed!

  13. Re:1 Degree Change, sure, but what's the StDev? by mellon · · Score: 5, Informative

    They do talk about it. You just (evidently) don't listen.

    Global temperature increase shifts the atmospheric circulation cells, so that they land in different places. It shifts the jet stream, so that weather is carried to different places. It shifts oceanic currents; there's a big concern that global warming may actually result in a major drop in temperatures in northern Europe. There are many factors that decide what the temperature will be outside your house today; global warming is not the largest factor by a long shot. But where the Hadley Cells, Ferrell Cells and Polar Cells land has a big effect on the weather you experience, and that _is_ affected by global temperature increases in the one degree range. These effects aren't necessarily temperature increases; they are just as likely to be more energetic storms, or droughts, or floods.

    However, it's also worth noting that 1 degree is currently considered a fairly unrealistic best-case scenario, because since we started trying to take some weak action to address Global Warming, China seriously ramped up the amount of coal they're burning, so atmospheric CO2 levels are going up faster than predicted.

  14. Re:We didn't really know how things worked before by angry+tapir · · Score: 4, Informative

    On balance it's probably natural for geeks (many of whom are naturally inquisitive) to question ideas which insist on substantial changes to our lifestyles with tenuous evidence behind them

    To quote Wikipedia:

    No scientific body of national or international standing has maintained a dissenting opinion; the last was the American Association of Petroleum Geologists, which in 2007 updated its 1999 statement rejecting the likelihood of human influence on recent climate with its current non-committal position.

    And so all these organisations came to the conclusion that human activity is playing a key role in global warming without any "credible evidence" (to use your phrase)?

  15. Re:We didn't really know how things worked before by KeensMustard · · Score: 5, Insightful
    Science can only be validly questioned by science. Constructing another framework based on non science (e.g feelings, or dogma) and presenting this construct as if it falsified the science is simply nonsensical. It's like trying to debate in a language you made up yourself. It is just babble.

    Therefore the fact that people do not like the implications of AGW does not, in anyway, make it less true. We are not choosing clothes from a rack. We are not debating whether the purple shoes will go with my slacks. And it's the implications that denialists do not like. Notably, no-one ever questioned Tyndalls experiment, nor whether the greenhouse effect was real until it became clear from the numbers that we needed to change our habits. Then suddenly, the whole theory was controversial.

  16. Re:We didn't really know how things worked before by Anonymous Coward · · Score: 5, Informative

    Can you name a me a single AGW "denialist" that you deem to be qualified enough to have their theories and research taken seriously?

    Yes. Richard Lindzen. If you ask for 2 it gets difficult ... there are a few "luke-warmers" though.

    Now can you name me a single scientist who denies the existence of gravity, that you deem to be qualified enough to have their theories and research taken seriously?

    Exactly!

  17. Re:We didn't really know how things worked before by TapeCutter · · Score: 5, Insightful

    So how many times do you answer the same question before you realise you're dealing with a troll or a shill? How many people still link and quote Anthont Watts thoughroghly descredited claims? Should the time cube guy be allowed to chew up research dollars just because he has a bunch of ideas contrary to modern physics?

    I think you are also bluring the "argument from authority" thing (which is about relying on a single source), science does in fact carry a certain authority in it's calim to have the best answer, if not the correct answer. It's authority comes from a meritocricy that Popper called "the republic of science" and what everyone else calls "consensus". It's the difference between "science says" and "a scientist says".

    --
    And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
  18. Re:We didn't really know how things worked before by _xen · · Score: 5, Informative

    See, that's the problem. Any scientist that questions it is immediately deemed unqualified or even unethical simply because they have bothered to question it.

    Oh come on Archer. The criterion for "suitably qualified" is not whether they personally agree or disagree with any position. It is simply whether they are literally suitably qualified, which is to say, are they working and publishing (in an ISI listed peer reviewed journal, i.e. not a phish journal like E&E) in the field, the holder of a chair in the relevant discipline etc.. And ultimately it's not what scientists say, but what the bulk of the published science says that we must defer to.

    Nor is there universal agreement among most expert climatologists. But the baby questions, such as is anthropogenic carbon in the atmosphere rising; are mean global temperatures rising; and are the two causally linked, are now settled in the affirmative. The scientific debate has largely moved on. And recent attempts to revive these questions by the very few suitably qualified scientists who do disagree with the mainstream has invariably resulted in disaster: Witness Lindzen & Choi (2009) (In Lindzen's favour, once the flaws in this paper were pointed out he withdrew it without hesitation), or the debacle surrounding Spencer and Braswell (2011).

    Now once he was presented with the body of the science, the editor of Remote Sensing (where Spencer and Braswell appeared) realised he'd been duped and took the appropriate course of action (for which see the link above). When are you going to wake up Archer, and face up to the fact that you've been duped too?

  19. The view from inside climate science by Anonymous Coward · · Score: 5, Insightful

    The original article is about the Little Ice Age primarily, and the only tie-in is the comment warning against relying on volcanoes to save us from warming / geoengineering man-made "volcanoes" to fix warming.

      But, ok, you want to ask the question "is it actually warming?" I'm a climate scientist-ish, I'll throw in a line. I recommend skepticalscience.com for it's superb evidentiary support for the theory of anthropogenic global warming (a.k.a. climate change).

      Yes - we have ample data demonstrating that it is warming, not only in the air but in the surface waters of the ocean (water absorbs some of the heat, it turns out - if only it would absorb more of it!). We have really really obvious evidence (seriously, just look at the satellite pictures) of dramatic summer sea ice loss. The troposphere (where we live - where our weather happens) has warmed about 1.3 degrees F over the last 100 years. This might not sound like a lot, but just integrate 1.3 degrees over the whole planet, and you're talking about a significant amount of energy.

      The stratosphere has cooled up to 6 degrees Celsius (yeah, that's right, mixing up the units) in some places, and higher atmospheric layers have cooled even more. Now, you might ask, why the cooling - this is supposed to be global WARMING, right? The mechanism behind stratospheric cooling is a bit complex, but think about it this way: Greenhouse gases (GHG's) trap more heat (absorbed and re-radiated long-wave energy) in the Troposphere (the lowest layer, where weather happens) than we would otherwise have. If that extra heat weren't trapped in the lower atmosphere, it would have to go somewhere else, right? So where would it go? It turns out, it would go back into space or, more importantly, into the upper layers of the atmosphere (stratosphere, mesosphere, ionosphere). Essentially, the GHG's play favorites with the atmosphere - they give the lowest layer more heat while depriving the higher layers of their ordinary allowance.

    Incidentally, this phenomenon allows us to distinguish GHG-driven heating from sun-driven heating. If global warming were caused by the sun alone, the temperature would increase in all layers of the atmosphere - the sun doesn't play favorites.

    But wait, how do we know it's people? Physics tells us CO2 absorbs long-wave radiation (and then re-radiates that energy in all directions). Simple energy balance calculations tell us that without CO2 and other greenhouse gases (but mostly the CO2, as it is slower to enter/leave the atmosphere than H2O) the earth would be too cold to support most life forms. Over and over again in Earth's long history, higher concentrations of CO2 are associated with higher temperatures (the very early Earth was very warm, despite a weaker sun - this is known as the Faint Young Sun paradox - but greenhouse gases were more abundant). We're pumping this gas into the atmosphere with careless abandon, and we can measure and observe that much of it stays there (removing CO2 from the atmosphere permanently by natural processes takes a loooong time). Even if we didn't measure warming and we couldn't measure CO2 (did I mention we can measure warming and CO2? We do it all the time) the laws of physics and the principles of chemistry allow no other possible conclusion than a future of warming (for most of us) and cooling (for anyone unfortunate enough to be stuck in the upper atmosphere).

    Sorry for the long post. Also, don't think for a minute someone does serious climate science without asking the questions "are we sure we know what we know?" or "are the computer models any good, like, at all?" about 3 times before breakfast. Seriously, people, we're pretty smart apes, this isn't "too complicated" or "too difficult" for us humans to figure out.

  20. Re:We didn't really know how things worked before by tgibbs · · Score: 4, Informative

    All theories, from gravity to evolution generalizations that can never be exhaustively tested, but that are to some degree accepted because they make testable predictions that have turned out to be correct. For example, we theorize that all masses, past, present, and future exert a gravitational force on all other masses, but almost all of the masses in the universe are not directly accessible for testing--we have tested only an insignificant fraction of them.

    Here's a list of some of the predictions of climate science that have been tested and have turned out to be correct

  21. Re:Call a spade a spade by _xen · · Score: 5, Insightful

    Using a "convenient one word label" turns the debate from scientific to political.

    But this is a political debate, not a scientific one. The scientific debate is conducted in journals and conferences not on this kind of forum and not by you and I. The scientific debate is largely over, or rather it has moved on from the issues which are still hotly contested in the political debate.

    It's focusing more on "us vs. them" than discussing the real issues at hand.

    The "real issue at hand" is what policy position, if any, ought to be adopted in light of the now established science, or if you prefer, the current best available science. Denialists have no interest in discussing the real issues. Quite the opposite, they are concerned with stopping the real issues from being discussed at all.

    We call people who disrupt democratic process with bombs with a convenient one-word label: 'terrorist.' You may object, but it makes conversation more convenient. So what would you call people who disrupt the democratic process with disinformation about science, regardless of whether it's about climate, AIDS, vaccines or whatever? We usually find it easier to identify these people as 'deniers' or 'denialists.' They would like to be called skeptics, but that is actually only more disinformation.

  22. Re:We didn't really know how things worked before by riverat1 · · Score: 4, Insightful

    Consensus is not when scientists get together and decide "We're going to have a consensus!" Consensus is what you have when (nearly all) scientists in a field no longer argue seriously about a particular subject except at the minute detail level because it isn't interesting any more.

  23. Re:Global Warming? Let the Intelligent Debate Begi by shutdown+-p+now · · Score: 4, Funny

    "Intelligent debate"? What kind of nonsense is that?! Everybody worth listening to knows full well that Slashdot posts aren't written, they're generated from a QRNG in CmdrTaco's basement, and comment scores reflect natural selection.

  24. Re:We didn't really know how things worked before by CoolBru · · Score: 5, Informative

    > As far as I know no one has created a model of the earth to test global warming or bred a large number of animals to create a new species.

    No-one that is, apart from those that have. There have been a fairly large number of the latter, both observing and inducing speciation in plants and animals.

    There are plenty of earth models for climatic and other purposes. It's clearly not practical to make physical models, so we have to make do with software ones which don't have such practical constraints. Their accuracy can be tested by seeing if older data can be used to predict more recent data (hindcasting), for example can data gathered from 1900 to 1960 in a given model be used to predict what the conditions were like in the 1960s? If they do, then you might consider some of that model's future predictions trustworthy too. This technique is used to test models of individual parts of an overall climate model, such as temperature changes, cloud actions, El Niño events, gas mixtures etc. Generally these models will only ever get better as research improves and computing power increases. Still, they are an approximation (as all models necessarily are), but as the IPCC said: "Despite such uncertainties, however, models are unanimous in their prediction of substantial climate warming under greenhouse gas increases". More info.

  25. Re:We didn't really know how things worked before by serviscope_minor · · Score: 4, Informative

    0) The people shouting loudest about how important this is stand to gain a significant amount of money, power, and public notice if people believe and act on their claims.

    Everywhere I go, I see teachers driving Ferraris, research scientists drinking champaign...

    As a research scientist, the best that they can expect to get, and in fact the goal that so many of them have in mind after 10-20 years of hard research is... a job which isn't guaranteed to terminate in 3 years.

    And, the best way do do that is to make a big name for yourself by turning over the old scientific establishment and coming up with something striking and new (supporting AGW definitely does not qualify as anti-establishment).

    If you think there's a cabal of scientists banding together on global warming for the money and power, then you are either astonishingly ignorant or a total moonbat.

    --
    SJW n. One who posts facts.
  26. Re:We didn't really know how things worked before by 1u3hr · · Score: 4, Insightful

    Here is a post a few spots up that completely negates your statement:

    Richard Lindzen. Wasn't he the guy who was recently debunked and had his papers withdrawn from publication because he was being paid for his position?

    The second a scientist takes on penny from an oil company, even after his work is published, he's instantly discredited, regardless of the quality or accuracy of his work. Yet, it is perfectly acceptable for a scientist to take money in the form of a grant from a government that stands to gain power over citizens.

    Rubbish. Lindzen didn't have his livelihood threatened, that's what the poster I was responding to insinuated. Being criticised is another thing entirely. Lindzen has had a long comfortable career. He didn't suffer for his opinions.

    He was pilloried though for LYING about his funding. See http://www.sourcewatch.org/index.php?title=Richard_S._Lindzen : "in 2007, Lindzen wrote that "his research has always been funded exclusively by the U.S. government. He receives no funding from any energy companies." Which was untrue.

    And, FYI, governments already have " power over citizens". I don't understand where you conspiracy nutjobs get the idea that global warming is a political issue that somehow helps commies. It doesn't help ANYONE. It's going to fuck us all.