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How Well Do Our Climate Models Match Our Observations? 560

bunratty writes "According to recent articles by Roy Spencer and John Christy, our climate models have done a poor job of predicting warming due to humans burning fossil fuels. They claim that we've observed only a fraction of the warming they predict. But when I look at the source they claim to use, the State of the Climate in 2012, I see that it shows a warming of 0.7 degrees Celsius worldwide since 1980, close to the 0.8 degrees Celsius warming predicted by the climate models. Take a look at the data for yourself. How well do our predictions match our observations?"
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How Well Do Our Climate Models Match Our Observations?

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  • by i kan reed ( 749298 ) on Thursday February 20, 2014 @12:52PM (#46295621) Homepage Journal

    Natural forcing actually add up to negative changes in temperatures(though at so small a value they wouldn't even show up on a graph of temperature forcing).

  • Re:Predictive Power (Score:5, Interesting)

    by bunratty ( 545641 ) on Thursday February 20, 2014 @12:54PM (#46295629)
    Following your advice, I looked at the overview from the first IPCC report [], and in section 2 it lists one prediction as about a 1 degree Celsius increase in temperature between the time of that report (1990) and 2025. It's not 2025 yet, but based on an observed warming of about 0.16 degree Celsius per decade, we should see a warming of about 0.8 degrees Celsius between 1990 and 2025. It falls a bit short of one full degree, but the prediction was literally "about 1 degree Celsius," and 0.8 degrees Celsius is in fact about 1 degree Celsius.
  • One small problem... (Score:5, Interesting)

    by cirby ( 2599 ) on Thursday February 20, 2014 @12:54PM (#46295631)

    The State of the Climate 2012 paper is... get this... from two years ago. After they had to start "adjusting" their models to reflect reality.

    When you look at the actual historical AGW models, we're below their "optimistic" model (the one where we cut CO2 drastically over the last couple of decades - which didn't happen). And a good 0.2 C below their "probable" models.

    If you're looking at predictions, go back and look at the climate models from the late 1980s and early 1990s. They're off, by a ridiculous amount.

    Out of 90 models (yes, ninety), a grand total of TWO managed to predict the current temperature.

  • Re:BS (Score:3, Interesting)

    by Salgak1 ( 20136 ) <[salgak] [at] []> on Thursday February 20, 2014 @12:55PM (#46295645) Homepage
    And yet EVERYTHING is now caused by AGW. Heat Waves. Cold Spells, Floods. Droughts. Today, I saw a report linking Crime to Global Warming. Last year, it caused prostitution for impoverished women. About the ONLY thing not linked to AGW is the Heartbreak of Psoriasis and Waxy Yellow Buildup. But hey, it's only February. . . .
  • by CaptainLard ( 1902452 ) on Thursday February 20, 2014 @01:33PM (#46295983)

    Or the fact that we are still coming off of an Ice Age that lasted for more than 100,000 years, and ended less than 10,000 years ago (Or the little Ice Age that ended in 1850). Several models predict that the average temperature at the END of the last Ice Age was 15-20C lower than today.

    Is global warming happening? Yes. Is the human race a contributing factor? Probably to some degree. Is the human race the only cause? No.

    I like this game.

    Do humans have the capability to mitigate their contribution to warming? Yes. Does any other warming phenomenon? No
    Do humans care if these warming effects drastically disrupt the climate that our current society has adapted to so well? Yes. Does anything else? No.

    Also a quick note, 20C over 10000 years is .002C/year. .7C over 30 years is .023C/year

  • by Layzej ( 1976930 ) on Thursday February 20, 2014 @01:59PM (#46296331)

    Also a quick note, 20C over 10000 years is .002C/year. .7C over 30 years is .023C/year

    Also worth noting is that the global temperatures didn't change 20C. The last glacial maximum was only 3C to 5C cooler than the present ( The height of the current interglacial period occurred about 8000 years ago. Since then temperatures have been dropping (up until recently).

  • by Anonymous Coward on Thursday February 20, 2014 @02:14PM (#46296583)

    Actually, most scientists in the climate field believe in AGW. They will continue to do so as long as it is easier to get funding for projects intended to prove it exists. They will cease doing so when it's easier to get funding for projects intended to prove it doesn't exist.

    No, relatively few individual scientists will change their mind, just those that are "respected" (i.e., get funding and whose papers get quoted) will be the "deniers" rather than the "zealots".

    Everyone agrees that global warming or cooling is going to happen with or without man's existence on Earth. Everyone agrees that man is efficient at extracting carbon from where it is sequestered and turning it into CO2. Everyone agrees that more CO2, in the absence of any other forces, will trap IR which will, in the absence of any other forces, increase global temperatures.

    What is much harder to get agreement on is the degree of change and if it's good, bad, or neutral. It's even harder to get agreement on the politics of reducing CO2 emissions from sequestered carbon sources - should we, who should pay, is nuclear a good alternative, do windmills kill birds, should we just reduce the world population (which would improve the average quality of life immensely if done right) and expect that the remaining people will migrate as needed as their local climate changes, ???

    When the next ice age does hit, as it surely will, humans will likely be wishing that politicians hadn't worried so much about AGW back in the 2010's.

    Of course, in reality, it doesn't make any difference. Humans adapt very poorly -- we have too few offspring, devote too much energy to get each one to sexual maturity, it takes too long for us to reach sexual maturity, and (in recent decades) we spend most of our medical resources saving the horribly unfavorable mutations which is exactly the wrong place to be putting resources if you care about the future of humans overall.

    The fantasies that we will somehow find a "dead" planet close enough to ours in climate and resources somewhere in the universe and be able to populate that as Earth becomes inhabitable are likely just that, fantasies. Such a planet likely already has some form of life on it and our environmental protection laws (once updated to reflect the new rock's existence) would prevent us from building anything or altering it as it would endanger native species. If there is "intelligent" (as we define it: as "smart", or delusional, as humans) life on Earth in 10 million years, it won't be human or have evolved from humans.

    So, have another scotch and party on.

  • by kwbauer ( 1677400 ) on Thursday February 20, 2014 @04:40PM (#46298359)

    "in the climate field"... The only way to get into "the climate field" is to believe in AGW so why the hell do only most of them believe it.

  • by AlphaWolf_HK ( 692722 ) on Thursday February 20, 2014 @06:57PM (#46299835)

    The thing is, it really doesn't matter how many scientists support it. Science isn't a democracy. See the pamphlet called 100 authors against Einstein. Einstein replied that it didn't need 100 people do disprove his theory of relativity, rather all it needed was one fact. I really hate how modern science has turned into this "if the majority believes it, it must be true." I'm sure the majority of the world still believes in creationism, but they're also still wrong.

    (By the way, who decides what makes you a scientist anyways?)

The other line moves faster.