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Earth Science

Little Ice Age: It Was Not the Sun 375

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.'"
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Little Ice Age: It Was Not the Sun

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  • Of course. (Score:2, Informative)

    by Anonymous Coward on Monday February 06, 2012 @11:15PM (#38949189)
    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. Yes, the sun is slowly getting hotter, but that's a long term trend.
  • by Geoffrey.landis ( 926948 ) on Monday February 06, 2012 @11:50PM (#38949421) Homepage

    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.

  • by Anonymous Coward on Tuesday February 07, 2012 @12:21AM (#38949581)

    Amazing how you manage to make yourself seem a victim of the moneygrubbing AGW scammers.

    There was actually some non-politically motivated criticism, and a group of scientists lead by a renowned physicist set out to double-check the work of AGW science (who had doubts regarding AGW) and sponsored by AGW doubters. What happened? Do you even remember or did you filter that out...

    There was some questions on the issue of bias due to the sponsorship, yet most in the AGW community seemed to welcome the effort to independently verify claims of global warming. And what was the result? AGW was confirmed as happening.

  • by mellon ( 7048 ) on Tuesday February 07, 2012 @12:25AM (#38949603) Homepage

    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.

  • by angry tapir ( 1463043 ) on Tuesday February 07, 2012 @12:29AM (#38949619) Homepage

    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 [wikipedia.org]:

    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)?

  • by Anonymous Coward on Tuesday February 07, 2012 @12:36AM (#38949651)

    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!

  • by TopSpin ( 753 ) on Tuesday February 07, 2012 @01:19AM (#38949831) Journal

    The hypocrisy doesn't help either. The ones screaming the loudest are the ones in the biggest houses with the largest fleets of SUV and private planes.

    Here [wikipedia.org] is Tom Brady's wife, a goodwill ambassador for the UN Environment Programme, lecturing [sealthedeal2009.org] us all about our responsibility to the 'environment.'

    Here [ibtimes.com] is her new house.

    Bring it to this malcontent backwater though and you're 'flamebait.' We suspend our outrage for our 1% when they say the right things and bury all those fools with the temerity to point out our group-think.

  • by _xen ( 79742 ) on Tuesday February 07, 2012 @01:42AM (#38949965)

    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 [mdpi.com] 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?

  • by EdZ ( 755139 ) on Tuesday February 07, 2012 @02:18AM (#38950123)

    denies the existence of gravity

    No, but there sure as hell are a lot who disagree on how and why it occurs, and the mechanisms behind it.
    We know the Earth changes global temperature, often wildly (we have testable records of this). We know the current global temperature is (we have multiple measurements of this). What we don't have is another spare Earth running with accelerated time to test whether injecting the quantities of CO2 that have been released (along with aerosols, particulates, and other assorted crap) will have a long term net warming effect, cooling effect, or something else, and the magnitude of that effect. We can create models to predict the effect, but we only have training data (past records), but no control data. To only current way to test to see if what we think will happen in 100 years is correct is to wait 100 years.

  • by _xen ( 79742 ) on Tuesday February 07, 2012 @02:19AM (#38950125)

    "Gravity" is not a theory.

    Neither is the mass of raw data which is routinely challenged by climate deniers, you know "warming has stopped it's been getting colder for the last x years ..."

    Comparing gravity to AGW is preposterous.

    I think you've missed AC's point which, if I may, was that an argument along the lines of "if you can't name any scientists you regard as reputable who disagree with a well-established sciency then you criterion for selecting reputability is obviously politically biased ... exactly!" is not a valid argument. I think that still stands even if gravity can easily be tested by high school physics students.

  • by tgibbs ( 83782 ) on Tuesday February 07, 2012 @02:39AM (#38950219)

    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 [bartonpaullevenson.com]

  • by KeensMustard ( 655606 ) on Tuesday February 07, 2012 @02:56AM (#38950283)
    The term denialist has a well documented entomology. It refers to the the state of denial, ('She/He is in denial'). See wikipedia entry.

    The term came into common usage because the target group referred (incorrectly) to themselves in their state of cognitive dissonance as 'sceptics'. Scepticism also has a precise meaning. It doesn't refer to people who reject scientific theory without presenting contrary evidence.

  • by CoolBru ( 798217 ) on Tuesday February 07, 2012 @05:33AM (#38951027)

    > 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 [talkorigins.org].

    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 [skepticalscience.com].

  • by serviscope_minor ( 664417 ) on Tuesday February 07, 2012 @06:35AM (#38951421) Journal

    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.

  • by Xyrus ( 755017 ) on Tuesday February 07, 2012 @10:29AM (#38953321) Journal

    Hmm. In your (insightful? Really?) response, I see a lot of opinion and ranting, but I don't see a single cogent statement that refutes any of the claims in the paper. They explain the lags, the feedbacks, and the modeling they used in their paper. Real climate even has a more layman's description of the mechanism: http://www.realclimate.org/ [realclimate.org] .

    Of course, you're probably counting on the fact that people rarely RTFA and fewer would RTFP. But basically your entire premise is incorrect and refuted in the paper itself.

  • by mangu ( 126918 ) on Tuesday February 07, 2012 @11:48AM (#38954577)

    Shouldn't all science be questioned?

    Yes, all science is questioned. The process is named "peer review". Do you know what the word "peer" [thefreedictionary.com] means? It means someone who has a similar standing.

    The work of scientists should be questioned by people who have gone to the trouble of studying and understanding what the subject is about. Not by trolls who repeat the bullshit spewed by corporations whose interests are hurt by the facts that scientists present.

"When the going gets tough, the tough get empirical." -- Jon Carroll

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