Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 


Forgot your password?
Close
typodupeerror
×

20th Century Warmest In 1200 Years 608

Posted by Zonk from the spicy-meatball dept.
gcranston writes "Research from the University of East Anglia in Norwich, U.K. shows that the 20th century was the warmest for the northern hemisphere since approximately 800AD. Historical climate data were calculated from weather 'proxies' such as tree rings, ice cores, and seashells from Europe, Asia, and North America, and attempted to address the shortcomings of earlier studies. The findings support the argument for global warming as a result of human interference rather than natural climate change."
This discussion has been archived. No new comments can be posted.

20th Century Warmest In 1200 Years More

20th Century Warmest In 1200 Years

Comments Filter:

  • Don't call it "global Warming" (Score:5, Funny)

    by mpitcavage ( 655718 ) on Friday February 10, 2006 @03:18PM (#14689763)
    It's "Global Climate Change",

    • Interesting... (Score:3, Insightful)

      by Seoulstriker ( 748895 )
      If this is the warmest in so many years, then back then it was hotter that what we have now.

      • Logic clew-by-four (Score:5, Informative)

        by 0xABADC0DA ( 867955 ) on Friday February 10, 2006 @04:17PM (#14690267)
        If the data they considered stops 1200 years ago then it can be correct that this was the warmest century in those 1200 years *and* it was colder before that. Similarly, if this was the hottest January on record that doesn't mean the hottest January ever.


        • A very distinct possibility is that their data collection methodologies are flawed.

        • if this was the hottest January on record that doesn't mean the hottest January ever.

          Given that Earth started out as a firey ball of lava, I'd say you're right.

        • Re:Logic clew-by-four (Score:4, Informative)

          by Jozer99 ( 693146 ) on Friday February 10, 2006 @08:16PM (#14691809)
          Let me explain a little about "Global Warming" for those who only know it from television news (many of us, including me a year ago).

          Global warming does not mean that every single place on the globe will get warmer at the same rate.  It is an average climate change.  In fact, many places will actually get colder.  Here is how it works:

          Because of the way the earth spins, and the distrobution of land and water, there are "climate bands" going around the globe.  At the top, there is a cold one (obviously), beneath that, a "warm" band, then a cooler one, and a warm band again at the equator.  This explains some of the wierd things about global climates, including how Alaska and Great Britian are at about the same latitude, but the climates are radically different.

          Global warming would cause these bands to shift.  At the top and bottom of the world, there would be significant warming on the ice caps, causing significant and possibly even complete melting.  Below that, the "cold" bands would move and put places with previously warm and wet climates into a colder, dry zone.  These areas would still be habitable, however, the ecosystems would suffer because they would have to deal with a completely new climate, either signicantly warmer, colder, wetter, or dryer than previously.

          At the equator, there would also be signficant warmning, causing deserts to grow rapidly (most signifcantly the sahara, which would destroy cropland in africa, and cause even more starvation).

          Also, a shift in the major air and water currents (eg the gulf stream) would create new and much more severe weather patterns all over the globe.  Some claim the record number of huricanes in the last year are the result of global warming (no real evidence of this that I know of).

          Lastly, Global warming is not necessarily caused by humans, or specifically by CO2 and other green house gasses.  The earth undergoes periodic, unpredictable and mysterious warm and cold periods, some short, some long.  The most recent was the "little ice age".  Look it up.  That being said, it has been well proven that CO2 absorbs heat from infrared light and releases that heat instead of reflecting it.  It is also true that humanity has been dumping much more CO2 into the atmosphere than ever in earth's history.  However, scientists will probably never have conclusive proof that this causes global warming, as earth's atmosphere is unimaginably complex.

          Hope this is informative. 

      • Implications (Score:4, Insightful)

        by Peter Mork ( 951443 ) <Peter.Mork@gmail.com> on Friday February 10, 2006 @04:21PM (#14690292) Homepage

        Not necessarily:

        Assume we are looking at n time intervals numbered 1, 2, ..., n. If the maximum observed temperature was in interval n, we can assert that this interval was the warmest of the last n intervals.

        Now consider interval 0. If this interval is warmer than n, the strongest assertion we can make is that the recent interval is the warmest of the last n. If the recent interval is warmer than 0, we could make a stronger assertion. However, the validity of 'warmest of the last n remains.

        In effect, you are assuming that the researchers made the strongest possible assertion. Another alternative is that they were only able to measure a certain number of intervals.

      • That's not true at all. Let's look at some example data, shall we?

        YEAR | AVERAGE TEMPERATURE IN BRITAIN (deg. C)
        0706 | 14
        0806 | 14
        0906 | 15
        1006 | 14
        1106 | 14
        1206 | 15
        1306 | 13
        1406 | 15
        1506 | 14
        1606 | 13
        1706 | 14
        1806 | 17
        1906 | 19
        2006 | 21

        Notice that even though 2006 is the hottest year of the past 1200, it in no way implies that any of the previous years were hotter, even going back over 1200 years. As shown in the data above, the earlier years could be far colder.

      • Re:Interesting... (Score:3, Insightful)

        by nwbvt ( 768631 )
        Also, this is just a BS statistic. Wouldn't it have been more consistent to say "20th Century Warmest in past 12 centuries"? By using a much smaller interval in the comparision, you get something that sounds much more extreme than it really is. 1200 years really isn't that long, especially considering half of that was during the little ice age.
    • "Research from the University of East Anglia in Norwich, U.K."

      And of course it's still 55F in most living rooms in East Anglia in Norwich, U.K.
    • It's "Global Climate Change",

      Shouldn't that be "Global Climate Change Theory"?

      (I think we should start appending "theory" to every vaguely scientific-sounding phrase. That'd soon end that particular bit of terminological silliness. ;-)

  • Global warming is a myth because we say it is. (Score:4, Funny)

    by Jim in Buffalo ( 939861 ) on Friday February 10, 2006 @03:19PM (#14689765)
    The findings of this study are hopelessly flawed in that they conflict with the principle that only the scientific positions of the campaign contributors to the ruling party in the United States are in any way valid. Please take your actual science with its actual testing and actual methods of deduction elsewhere, as we've got Italian sports cars, mansions, and private jets to buy.
    • Will Ferrell - Bush on Global Warming. Quicktime Video.

      http://www.transbuddha.com/mediaHolder.php?id=1147 [transbuddha.com]
    • You've interpreted this as proof of something with a political message. What I like about this report is that it isn't politicized at all. It's stating the facts, not going to extreme left positions and saying humans are causing the earth to heat up.
      • You said:

        It's stating the facts, not going to extreme left positions and saying humans are causing the earth to heat up.


        The article said:

        The researchers think their work bolsters the case that global warming due to human activity has created a change in climate unlike anything seen in more than a millennium.


        What the fuck?

        -Peter

  • I live in Michigan (Score:2, Funny)

    by Anonymous Coward
    and all I can say is "MMMMMMMM, toasty!"

  • Ingrate! (Score:3, Funny)

    by blackcat77 ( 857269 ) on Friday February 10, 2006 @03:20PM (#14689776)
    It's the Bush Administration's gift to the world -- lower heating bills and summer vacations all year round!
    • Lower Heating Bills now, but that also means higher cooling bills when it's 100 degrees outside.

    • Global Warming Good (Score:4, Interesting)

      by jgardn ( 539054 ) <jgardn@alumni.washington.edu> on Friday February 10, 2006 @04:45PM (#14690482) Homepage Journal
      On a more serious note, there are people that think global warming is good. Receding ice caps leave minerals in the ocean that encourage sea life and will help feed the world's population. Receding glaciers will open up valuable, fertile ground that hasn't been farmed for nearly a thousand years. And the increase in temperature will raise the humidity world wide, perhaps turning the Sahara desert into the rain forest it used to be, and expanding the world's rainforests to new latitudes.

      I could also see a future when there is no freezing winter, it's jus a year-round summer like on the tropical islands. Maybe then we won't be losing so many homeless to the random snowstorms of today.

      I often wonder what the world would be like if every year the north and south poles melted. Would the entire world turn into a humid tropical paradise?

  • What would scientists think? (Score:3, Funny)

    by doombob ( 717921 ) on Friday February 10, 2006 @03:20PM (#14689777) Homepage
    Not all scientists agree that the 20th century is the warmest period in recent history

    Would they still think this in lieu of the following recently uncovered data?

    Global Warming vs. Ice Age [googlefight.com]
    Global Warming vs. Global Cooling [googlefight.com]
    Global Warming is true vs. Global Warming is false [googlefight.com]

  • Food for thought (Score:5, Informative)

    by MyNymWasTaken ( 879908 ) on Friday February 10, 2006 @03:21PM (#14689787)
    There has been a 19.4% increase in the mean annual concentration of CO2 in the atmosphere from 1959 to 2004.

    During the 1959-2002 period, the total CO2 emissions equaled ~220 gigatons; ~14% of the atmospheric CO2 in 1959.

    In 2002, Humanity pumped 7 gigatons (6975 megatons) of CO2 into the atmosphere. That is almost 4 times the emissions from 50 years ago (1952: 1795 megatons), and is more than was released from 1751-1886 (136 years: 6732 megatons).

    There is a close correlation between Antarctic temperature and atmospheric concentrations of CO2. The extension of the Vostok [antarctic ice core] CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 thousand years.

    Cites:
    Atmospheric carbon dioxide record from Mauna Loa [ornl.gov] [ornl.gov]
    Global CO2 Emissions [ornl.gov] [ornl.gov]
    Historical carbon dioxide record from the Vostok ice core [ornl.gov] [ornl.gov]
    Earth's atmosphere [wikipedia.org] [wikipedia.org]

    • Re:Food for thought (Score:5, Informative)

      by OverlordQ ( 264228 ) on Friday February 10, 2006 @03:34PM (#14689897) Journal
      "From 1986 to 2000 central Antartic valleys cooled .7 C per decade with serious ecosystem damage from cold"

      'Antartic climate cooling and terrestrial ecosystem response' Nature 415: 517-20

      ----

      "Both satellite data and ground stations show slight cooling over the last 20 years."

      'Variability and trends in ANtartic surface temperates from in situ and satellite infared measurements' Journal of CLimate, 13: 1674-96

      ----

      "Side-looking radar measurements show West Antartic ice is increasing at 26.8 gigatons/yr. Reversing the melting trend of the last 6000 years"

      'Positive mass balance of the Ross Ice Streams, West Antarticia' Science 295: 476-80

      ----

      "During the last four interglacials, going back 420,000 years, the Earth was warmer than it is today."

      'CLimate and atmospheric history of hte past 420,000 years from the Vostok Ice Core, Antartica' Nature 399: 429-36

      ----

      "Less Antartic ice has melted today than occured furing the last interglacial"

      'Radiocarbon constrains on ice sheet advance and retreat in the Weddell Sea, Antartica' Geology 27: 179-82

      ----

      The Sahara has shrunk since 1980

      'Africans go back to the land as plants reclaim the desert' New Scientist 175, 21 September 2002.

      ----

      On the other hand sea level *is* rising, as it has been for the last 6000 years since the satart of the Holocene, about 10-20 cm every 100 years.

      http://www.csr.utexas.edu/gmsl/main.html [utexas.edu]

      ----

      Hell I could throw in stats and references about the decreases in tropical storm activity, but I think I've made my point enough.

      • Re:Food for thought (Score:5, Interesting)

        by lbrandy ( 923907 ) on Friday February 10, 2006 @04:22PM (#14690297)
        The problem here, fundamentally, is too many science-types go to unending lengths using bad science and bad use of statistics to prove themselves right. This conversation constantly degenrates into two uninformed groups of people spouting completely false nonsense at each other based entirely on a misuse of statistics. Even in this slashdot thread you will see people getting modded up for citing (incorrectly) correlative evidence as causitive evidence.

        The fundamental issue here is correlation. Good climatologists are at war with correlation implying causality. They are unable to produce proper control experiments, so no matter how convincing their results, it's able to be dismissed by others. No good science should look at correlative evidence (as you have stated plenty) and draw conclusions. Guess what, since 1980, Jupiter has seen a HUGE increase in the number of comet strikes of the previous decades. But we can't pin that on global warming.

        The fundamental question is how much has humanity effected the global warming of this planet. Just showing that it is warming is completely and totally irrelevant. The important scientific question, and the one most difficult to answer, is how much humans have contributed. The methods whereby CO2 heats up a planet are fairly well understood, and no one with a sane state of mind can deny that humanity has made things worse. The scientific debate remains to what degree. Slashdot karma-whores can continually abuse the general lack of statistical know-how by stating "look how much warmer it is now!" and get modded up. The fact of the matter is using the metric of "difference in temperature in time" is completely and utterly meaningless in a debate about humanity's contribution to global warming.

        And we don't even need to get into the ridiciously horrible statistical fallacies possible when one begins using "extremes" and "records" as a basis for drawing conclusions.

      • Re:Food for thought (Score:5, Interesting)

        by FhnuZoag ( 875558 ) on Friday February 10, 2006 @04:47PM (#14690501)
        Let's tackle this one by one.

        'Antartic climate cooling and terrestrial ecosystem response' Nature 415: 517-20

        "Side-looking radar measurements show West Antartic ice is increasing at 26.8 gigatons/yr. Reversing the melting trend of the last 6000 years"

        This is predicted by climate change models. The cause is precipitation - increase in ocean temperature puts moisture into the air, which comes down as snow at the central regions of the poles. Meanwhile, the edges of the polar ice masses melt.

        "Both satellite data and ground stations show slight cooling over the last 20 years."

        Is that from 1996? Post 1999, it emerged that the satellite data were making systematic errors. After correcting those errors, the measurements now support GW. As for ground, see above.

        "During the last four interglacials, going back 420,000 years, the Earth was warmer than it is today."

        "Less Antartic ice has melted today than occured furing the last interglacial"

        But the onset of those temperatures was much, much slower than now. That's why global warming is so alarming. We're going to get the added temperature from the interglacials on top of the unrelated human caused changes,

        The Sahara has shrunk since 1980

        Title - plants reclaim the desert. Why? Perhaps the plants are better adapted to desert enivironments. Perhaps global warming has increased local humidity. Sahara expansion is more complicated than just a matter of global warming effects.

        Note that *none* of the above have concluded that global warming is contradicted. They just sound like they contradict global warming, when what is happening is precisely what one would expect.
      • The problem is, for every isolated instance of cooling that you dig up, someone else can dig up a (or, more likely, a whole bunch) of isolated instances of warming. This kind of argument doesn't get us anywhere.
    • I don't want to sound like I'm saying global warming isn't happening, but I think it's fair to add some more data into the mix:

      While CO2 emissions have increased in the last 50 years, what about much earlier? For instance, are we now putting out more CO2 than in the 1700s and 1800s? I don't know, I'm asking. Now, we have more cars and coal-fired power plants. Then, we were burning wood and coal and such in our houses for heat.

      It is also plausable that emissions from then are effecting us now.

      I think global

      • Re:Food for thought (Score:3, Informative)

        by asr_man ( 620632 )
        ...1700s and 1800s? I don't know, I'm asking. Now, we have more cars and coal-fired power plants. Then, we were burning wood and coal and such in our houses for heat.

        Except that back then "we" were much smaller. Several millions, vs. 6 billion now. Get real.

    • Re:Food for thought (Score:4, Informative)

      by Jerry ( 6400 ) on Friday February 10, 2006 @03:59PM (#14690132)
      Except for the fact that water vapor is SEVEN TIMES the green house gas that CO2 is, and it is present in the atmosphere in MUCH MUCH higher concentrations. Over all, water vapor contributes 280,000 time more to the greenhouse effect than CO2, and it's been doing it for ages, long before CO2 rose 25% to a measley 375 parts per million.

      Possibly the real contributor to global warming is not the warm fuzzies of CO2 but the the heat itself that is released when Carbon based fuels are burned. A coal, oil or gas burning power plant needs to waste one unit of energy for every unit of energy it delivers to the consumer, and that is with the power plant operating at close to 100% efficiency. The worse the efficiency the worse the heat waste.

      Eventually, all energy generated or wasted by power plants ends up as waste heat. That waste heat raises the mean temperature of the atmosphere until the T gets high enough so that the energy radiated (proportional to T^4) back into space equals the total of the incident Solar energy and the waste heat energy.

      Atmospheric scientists know that the concentration of CO2 is not high enough by itself to cause global warming, so they postulate a "trigger" or "catalyst" effect, which is unproven. Neither my theory nor theirs can explain the last hot house period that occured 1,200 years ago. Then, the CO2 was lower than it is now and there were no power plants spewing heat, so the burning of fossile fuels was not the cause. That leave other possible causes: solar output or volcanos, to name a couple.

      • Re:Food for thought (Score:4, Informative)

        by MyNymWasTaken ( 879908 ) on Friday February 10, 2006 @04:07PM (#14690191)
        I know this is slashdot, and nobody RTFA, but damn...

        The article did not say that it was warmer than today 1200 years ago. It said the reliable historic data goes back 1200 years, and the current readings exceed it all in terms of magnitude and extremes.

      • oh, good frickin' christ almighty!!!!!! (Score:4, Informative)

        by Intraloper ( 705415 ) on Friday February 10, 2006 @10:05PM (#14692311)
        "Except for the fact that water vapor is SEVEN TIMES the green house gas that CO2 is, and it is present in the atmosphere in MUCH MUCH higher concentrations. Over all, water vapor contributes 280,000 time more to the greenhouse effect than CO2, and it's been doing it for ages, long before CO2 rose 25% to a measley 375 parts per million."

        The residence time of water vapor in the atmosphere is very short, on theorder of a few weeks. Perturb the equlilibrium for water vapor, and within a very short time, the atmosphere returns to equilibrium. The residence time for CO2 is many, many, many orders of mgnitude longer. This means that CO2 increases can create long-term perturbatins in global atmospheric heat flow, but water vapor cant. The climate people refer to this with the pharase, "CO2 is a driver, water is a feedback."

        "Possibly the real contributor to global warming is not the warm fuzzies of CO2 but the the heat itself that is released when Carbon based fuels are burned. A coal, oil or gas burning power plant needs to waste one unit of energy for every unit of energy it delivers to the consumer, and that is with the power plant operating at close to 100% efficiency. The worse the efficiency the worse the heat waste. Eventually, all energy generated or wasted by power plants ends up as waste heat. That waste heat raises the mean temperature of the atmosphere until the T gets high enough so that the energy radiated (proportional to T^4) back into space equals the total of the incident Solar energy and the waste heat energy."

        That waste heat radiates VERY FAST. Ever notice how cold it gets at night? That is due to radiative heat loss. Add more heat at the surface, and the excess is very rapidly lost. You might also want to calculate the ratio of human heat release to heat input from solar irradiation; the results might show you that this argument is pretty weak.

        "Atmospheric scientists know that the concentration of CO2 is not high enough by itself to cause global warming, so they postulate a "trigger" or "catalyst" effect, which is unproven. Neither my theory nor theirs can explain the last hot house period that occured 1,200 years ago. Then, the CO2 was lower than it is now and there were no power plants spewing heat, so the burning of fossile fuels was not the cause. That leave other possible causes: solar output or volcanos, to name a couple."

        Your first sentence her is simply absurd. Our planet is not a ball of ice only becaus e of global warming due to CO2. The question is how much the ADDITIONAL CO2 humans are adding to the atmosphere is causing ADDITIONAL warming. And we know that effect is happening; the debates are over how much additinal warming we are/will going to experience with this much additional CO2. That discussion involves known feedback effects (not triggers) like waramer temps causing increased atmospheric water content, for example, leading to a magnification of the warming effect. BTW, this article does NOT say it was hotter 1200 years ago. That is simply as far back as their analysis goes. Other good studies show it was NOT as warm than as it is now.

  • OK lets stop before it starts (Score:3, Insightful)

    by OverlordQ ( 264228 ) on Friday February 10, 2006 @03:23PM (#14689802) Journal
    Historical climate data were calculated from weather 'proxies' such as tree rings, ice cores, and seashells from Europe, Asia, and North America, and attempted to address the shortcomings of earlier studies.

    And we all know how accurate and exact historical measurements are.

  • Cue the misunderstandings (Score:5, Insightful)

    by Anonymous Coward on Friday February 10, 2006 @03:24PM (#14689816)
    Let's take a pool on exactly how many posts this story will receive from partisans claiming that because the earth has been this warm in the past (the 800s) through natural causes, the earth either is not unusually warm now, or if it is warm now it must be because of natural causes--

    not realizing that (1) the thing that makes manmade global climate change distinguishable from natural global climate fluctuations is not how warm the earth has become, but how quickly and consistently the earth has warmed since the industrial revolution;

    and (2) the problem with manmade global climate change is not how warm the earth is now, but how warm it will become if this consistent, quick rise continues...

    What's your guess? 10? 40? 100?
    • Mod parent up. The single most important thing to remember about the Earth, and geology and climatology in general is that things happen very slowly. Certainly, there are fast, catastrophic events like Volcanos erupting and Earthquakes changing the landscape, but even those take enormous amounts of time to set up.

      Generally speaking, 500 years is an extremely short time frame for major change to happen on the planet. To see climate change in under 100 years is distressingly fast.
      • And yet mammoths froze standing up with food still in the stomache in vast, vast areas. And yet, flowers froze while still in bloom. Nope...everything that has every happened on earth, climate wise, is known to take thousands of years. Ya right...

        I'm feeling pretty good when I say that that flowers don't stay in bloom for thousands of years at a time and mommonths don't take thousands of years to digest large quanities of lush vegitation. Simple fact is, there is more evidence that suggests periodically
    • Mod parent up. This is exactly the point.

      Look, if you combine the two unassailable points that
      1) injecting vast amounts of carbon into the atmosphere poses a substantial risk of climate change
      (any "scientist" here care to deny the greenhouse effect?)
      and
      2) we are nearly certain to run out of oil in the next 20-100 years

      it makes absolutely no sense to sit on our thumbs and wait until we're really fscked to work on changing our energy infrastructure. It takes a *little while* to replace every single petroleu
  • We are finally comiing out of this 1200 year cold spell. I'm looking foward to a milder climate.. California and Lousiana were too big anyhow. I think people in really cold and really dry place deserve some better weather for a change.
  • Cus, you know, in 800 a.d. we were generating a whole lotta greenhouse gasses too.

    I'm not gonna say it isn't happening, but it calls to mind a quite from last year's Dr Who:

    "You spent soo much time worrying that you never considerd you'd survive."

    I'm fully sure a little heat won't kill us off. Make us grumpy? Yeah, change our diet? yup. Dead? nah.

  • What happened in 800 AD? (Score:3, Insightful)

    by krgallagher ( 743575 ) on Friday February 10, 2006 @03:27PM (#14689840) Homepage
    "Research from the University of East Anglia in Norwich, U.K. shows that the 20th century was the warmest for the northern hemisphere since approximately 800AD. ... The findings support the argument for global warming as a result of human interference rather than natural climate change"

    Help me out here. If it was warmer in 800 AD, what 'human interferance' caused the global warming in the 9th century?

    • Comment removed (Score:5, Funny)

      by account_deleted ( 4530225 ) on Friday February 10, 2006 @03:32PM (#14689881)
      Comment removed based on user account deletion

    • Re:What happened in 800 AD? (Score:5, Interesting)

      by MrFlibbs ( 945469 ) on Friday February 10, 2006 @03:42PM (#14689950)
      The article doesn't say what happened in the 8th century, just that tree rings don't reliably go back any farther. They must be using only specific species of trees, though, because there there are several species of living trees that are much, much older. Do their rings not reflect temperature, too?

      The article contains almost no technical data, but it does say there have been been conflicting results:

      "In 2003, a team led by researchers from the Harvard-Smithsonian Center for Astrophysics announced that it believed the 20th century wasn't the warmest, nor the one with the most extreme weather of the past 1,000 years.

      "But this research has been criticized for its selection of the indicators used to estimate historic temperatures, among other problems."

      The article doesn't say what indicators the Harvard-Smithsonian group used, just that they think their indicators are better.

  • Snapshot (Score:3, Insightful)

    by AnonymousJackass ( 849899 ) on Friday February 10, 2006 @03:28PM (#14689851)
    The findings support the argument for global warming as a result of human interference rather than natural climate change.
    No they don't. What about the Little Ice-Age? [wikipedia.org] That was a major gloabl climate change that was certainly not induced by man.
    Fact is, we're looking at a ~2000 year snapshot of an incredibly comlex system that's a few billion years old.
    I'm not saying that there isn't claimte change -- of course there is. I'm also not saying that man doesn't affect it -- of course we do. But what I'm saying is that we don't know how we are affecting it. Maybe the "Little Ice-Age" ended because of man. Perhaps we saved ourselves from freezing to death by creating a cozy CO2 blanket?
    My 2c...

    • Re:Snapshot (Score:4, Interesting)

      by Hoi Polloi ( 522990 ) on Friday February 10, 2006 @04:03PM (#14690165) Journal
      "That was a major gloabl [sic] climate change"

      If you read the article you cited it says:
      "While most believe the LIA to be a global event, some question this."

      It may have been a localized event restricted to Europe, possibly a disruption of the Gulf Stream?

    • Junk Science Link (Score:3, Interesting)

      by xocp ( 575023 )
      Here is some commentary on this article from the Junk Science people:

      http://www.junkscience.com/feb06/NotCO2.htm [junkscience.com]

      I find their opposing views are sometimes interesting.

    • Re:Snapshot (Score:4, Insightful)

      by lgw ( 121541 ) on Friday February 10, 2006 @04:40PM (#14690447) Journal
      A stable climate is a myth. There's no evidence of such a thing.

      It's true that human CO2 emissions are pushing climate change in some direction, but no one has a clue whther the results of that change will be more or less pleasant then the climate change that would have happene without human intervention.

      So we don't know which way we're driving, all we know is we're driving quickly. That's reason for concern, to be sure, but not for despair.

  • How old? (Score:2, Insightful)

    by Palshife ( 60519 )
    In other news, the Earth celebrated its 4,572,366,124th birthday yesterday. When approached for comment, the Earth joked, "Hey, you think I'm old you should go as the Sun HER age. Just do it from a distance, know what I'm sayin'?"

    Our sample is too small.
  • First I seriously doubt they can truly measure the "spikes" many centuries ago as accurately as we can now. Just as we could not count the true number of hurricanes and tropical storms a mere 50 years ago. Yeah its warming, but then what explains the "Medieval Warm Period"? I want to know. If they can explain that then perhaps they can see a correlation with today or point out why today is different.

    Yet they will only use that older "warm period" as a reference and never explain it. The explanation wil
  • That will give me so much comfort while I am digging out from the foot or more of snow that is forecast this weekend!

    Heartless bastards!

  • Okay, so it's the warmest century in the northern hemisphere since 800A.D.

    ( I mean, this is an improvement. I mean, people claiming a lack of science and rationality on the opposing viewpoint while looking at only 200 yrs of data seemed a bit moronic IMHO. So now, we've expanded our range of evidence to finally have some shred of evidence which might insinuate that we are warmer than the last 1,000 yrs.

    Okay, but what about prior to that? 4,000 yrs, 10,000yrs, 120,000 yrs?

    How do we compare?

    I mean, any stud
    • 3) FUTURE: Scientists predict instability of weather, saying temperatures will cycle rapidly from warming to cooling periods over periods of 2-3 to 200-300 yrs.

      Well, I know that for at least the past 35 years (and perhaps even longer) these temperature cycles you describe occur - and very rapidly.

      I've noticed this pattern where a period of global warming occurs over the course of several months, culminating in a period of almost overwhelming heat. This is followed by a rapid and drastic reduction in glo

  • But what about a global coincidence theory [satirewire.com] ?
    Or, it might be the fault of the sun - we didn't have sun 100 years ago, right ?
    Hey, Michael Crichton himself says this global warming thing is not real - I guess you hippie pinko lesbian communist godless gay-marrying terrorists would claim that global warming is real while Jurassic Park isn't ?
    And think of all the horrors that would happen if we cut down fuel consumption for nothing: our children would have to breathe this totally clean and transparent air, won'
  • What kind of chariots were they driving around in 800AD that warmed things up so much?
  • What if our idolatry has finally angered the FSM, and due to our overabundance of salty H2O, He's trying to raise the temperature so that He can make perfect al-dente noodles out of us!!????

    We must all try to eat more spaghetty!
  • People get so excited/concerned when they hear things like 'warmest in 1200 years'. I suppose if your a bible-thumper that seems like a long time, since the earth has only been around for a few thousand years.

    For the rest of us, 1200 years is less than a fraction of a percent of the age of our planet. Hence the warmest in 1200 years shouldn't lead anyone to believe it's abnormally warm at all.

    Maybe when I hear "The warmest in 500 million years" I'll likely say to myself, "Damn, that's not good."
  • Don't be deceived. The advocates of global warming could very well be wrong. See this article which cites a Stanford climatologist who advocated in the mid-70s that the world was cooling:

    http://www.discover.com/issues/feb-06/rd/global-co oling/ [discover.com]

    Perhaps the most enlighted part of this short article appears in the last paragraph:

    "Science is a self-correcting institution," Schneider says. "The data change, so of course you change your position. Otherwise, you would be dishonest."

  • Earth's Magnetic Reversal Is Near and Overdue (Score:4, Interesting)

    by ScrewTivo ( 458228 ) on Friday February 10, 2006 @03:52PM (#14690052) Homepage
    Earth is way overdue for a magnetic field reversal [wikipedia.org]. They have an average interval of 1/4 million years and it has been 3/4 million already since the last one. Some say it is beginning with the loss of a magnetic pole in certain places in the southern hemisphere. It could be the cause of the ozone layer loss because as the field weakens it radius at the poles grows. When the field is strong the field meets at the poles in a tight radius.

    Here are some cool sims [psc.edu] from Los Alamos National Laboratory.
     
    As we lose protection more radiation gets through and mother earth gets a temperature. I'm not saying that 100 years of intense burning hasn't contributed but this seems to be an ignored fact that may be contributing in a large manner.

    I first heard of this from watching a NOVA program. Here is the NOVA site on earths magnetic fields with some animations [pbs.org].

    Ok, now where did I put the SPF 10,000?

  • I feel like I'm taking Crazy Pills! (Score:3, Insightful)

    by jamesdps ( 953530 ) on Friday February 10, 2006 @03:57PM (#14690106)
    I'm going insane here -- everyone is saying "how does this prove anything if it was warmer in 800AD?" THAT'S NOT WHAT THE ARTICLE SAYS! "Warmest in 1200 years" does NOT implicitly mean it was warmer 1200 years ago, people -- read the article, we CAN ONLY TEST BACK 1200 years using ice cores, trees, etc.... it was COLDER 1200 years ago, that's what the article says... and as for the folks who mentioned the Little Ice Age, etc. -- yes, they mention that too (and the Medieval Warm Period from 890 to 1170), but both eras were not CONTINUOUSLY warm or cool, but were PUNCTUATED by hot and cold SPELLS... The concern of global warming is that the CONTINUOUS temperature is changing. I will concede that without data before 800AD, the study is looking at a pretty small sample of time, and that there are so many factors in such a hugely complex weather system to take into consideration, so I have no problem at all with those arguments, just with the fact that the majority of people here seem to be good at quickly sorting through text looking for keywords (such as "since 800AD") without actually COMPREHENDING what they are reading.... /rant.

  • But... But... (Score:4, Funny)

    by XMilkProject ( 935232 ) on Friday February 10, 2006 @04:01PM (#14690143) Homepage
    I thought yesterday Slashdot told me there was no such thing as time. So 1200 years ago is actually now. I'm so confused.

  • Maybe we're looking at this the wrong way... (Score:3, Interesting)

    by PFI_Optix ( 936301 ) on Friday February 10, 2006 @04:13PM (#14690238) Journal
    So we're just now back where we were in 800 AD?

    Is it possible that the climate is just snapping back from a thousand-year cold spell? Hasn't it been suggested that the dark ages were in part caused by a drastic drop in temperature, possibly due to abnormal volcanic activity?

    I doubt anyone is denying the reality of global warming/global climate change these days, but stuff like this certainly gives me reason to wonder if it's mere vanity that makes us so certain that we are responsible for the events we are observing.

  • Duh....its the end of an ice age stupid (Score:3, Insightful)

    by katorga ( 623930 ) on Friday February 10, 2006 @04:15PM (#14690248)
    The last ice age started melting roughly 10,000 years ago. The climate has been on a warming trend since that time. The average temperature for the earth over the historical period since complex life developed is much warmer than it is now. Logically, our current mean temperatures are abnormally cold compared to the mean temperatures over the last 35 million years.

    The high probability is that "global warming" is simply the globe resetting from the "global cooling" of the last 100,000 years. That may not be good for us, since we evolved to live in a cooler climate, but its normal for the planet.

    At the end of the day, the argument is not how to prevent global warming since that cannot be done. The argument is how to adapt to the new conditions.

  • Cost benefit analysis (Score:5, Interesting)

    by forand ( 530402 ) on Friday February 10, 2006 @04:31PM (#14690372) Homepage
    So here we are again, another long rant from two sides of an argument where those arguing are not in possesion of most of the facts.

    It always amazes me that these two sides will get into bitter feuds over this subject and no one seems to want to put it in any context. For me what it comes down to is this: we can spend a lot of money, time, and research trying to find out if we are a contributing factor to global warming, only to discover it may be too late, or we can spend even more money, time, and research trying to change the way we interact with the atmosphere. And in the end if those who claim that global warming is impacted by humans are right and we listened to them then we are on our way to fixing it and have a cleaner environment for the future. If they are wrong and we listened to them we still have a cleaner environment and we might just find that all those chemicals we were pumping into the atmosphere had other effects which would then be limited. If, on the other hand we don't listen to them and they are right then we have to learn to live in a new world climate and deal with the vast ammounts of crap we have been pumping into the atmosphere for centuries.

    What it comes down to, for me, is this: do we want to risk the global climate on this? Is it worth the piece of mind to know that what happens is out of our control instead of our fault?

Slashdot Top Deals

"Here comes Mr. Bill's dog." -- Narrator, Saturday Night Live

Close