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Earth Science

Reducing Climate Change Uncertainty By Figuring Out Clouds 249

Posted by Soulskill
from the look-an-article-about-actual-clouds dept.
Most climate scientists agree that the Earth's climate is getting warmer, but models predicting the severity of the temperature rise span a (relatively) broad range. One big reason for this is the difficulty in modeling things like cloud cover and how different air masses mix and move around each other. "Specifically, they have differences in how water-rich air at the bottom of the atmosphere gets mixed with the layers immediately above it. In some cases, this mixing increases rapidly as the temperature rises, effectively drying out the lower atmosphere and suppressing cloud formation there. This in turn would enhance the warming effect. In others, the increase in mixing is more gradual, limiting the impact of warming on clouds. The former produces a higher climate sensitivity; the latter a lower one. ... So, the authors turned to the atmosphere, using data to determine the relative importance of these processes (abstract). In the end, they find that the models that dry out the lower atmosphere more quickly are likely to get the process right. And, in these models, the mixing increases the drying rate in the lower atmosphere by about five to seven percent for each Kelvin the Earth's temperature increases. In contrast, the rate of evaporation, which adds moisture to the lower atmosphere, only increases by two percent for each Kelvin. Thus, the lower atmosphere dries out, cloud formation there is suppressed, and the planet warms even further. How much more will it warm? Quite a bit."
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Reducing Climate Change Uncertainty By Figuring Out Clouds

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  • meta stable (Score:2, Insightful)

    by Anonymous Coward on Wednesday January 01, 2014 @04:26PM (#45839699)

    As a physicist I do not take modeling of the atmosphere as we understood it now serious.

    The atmosphere is too much a chaotic system with many (meta-) stable states.

  • Models vs models (Score:5, Insightful)

    by cirby (2599) on Wednesday January 01, 2014 @04:42PM (#45839807)

    The study assumes that the models that show lower amounts of warming are the "less accurate" ones, and the models with higher warming are going to be "more accurate." Eventually, that is.

    The problem is that all of the climate models that predict AGW have been wrong, and the ones that show the least amount of actual warming are the ones that are least wrong at this point. So their solution is to come up with yet another one-dimensional computer model that shifts the possible warming a few decades into the future.

    The study also suggests that the water vapor in the lower atmosphere will more or less migrate up - which is not happening, according to actual observations by satellites.

    It's like the old AGW models, which predicted a "tropical hot spot" a few miles up that would happen due to AGW - and which never appeared.

  • by flaming error (1041742) on Wednesday January 01, 2014 @05:00PM (#45839901) Journal

    "The study assumes"
    No, the study concludes.

    This political debate waged in selective pseudo-scientific microquibbles is silly. It's really pretty simple.

    1) You can trust the process and presume that if the research scientists are converging on the basics, they're probably on the right track.

    2) You can prove them wrong - on scientific turf, not the comments section of a news article - and earn yourself a nobel prize and the undying thanks of millions of concerned citizens

    3) You can shut the fuck up.

  • Is to change to using an absolute scale of temperature like Kelvin

    Not really... they could have said "degrees" and it would have held true for all parts of the world using Celsius (including scientists in the US). The Kelvin bit is just silly, as Kelvin just sets 0 at a different point along the same scale as Celsius (0 being no energy vs 0 being freezing point of water). When you're measuring the temperature delta, Kelvin vs Celsius is meaningless (373.15 - 273.15 = 100 - 0).

  • Re:But I heard (Score:5, Insightful)

    by Kohath (38547) on Wednesday January 01, 2014 @05:32PM (#45840175)

    People making irresponsible and extreme statements about climate need to be disavowed by scientists or the science itself will lose credibility with the public. To a large extent, it already has -- and deservedly so. Get it back by being honest and open and by staying away from politics. It's going to take a really long time.

    And, yeah, I understand uncertainty and error bars. When the actual, measured temperatures are outside the error bars, the models need to be declared to be incorrect. My understanding is that this should happen within the next few years for many models, if measured warming trends continue.

  • by khallow (566160) on Wednesday January 01, 2014 @05:45PM (#45840323)

    At this point nobody in the scientific community is predicting global warming - you don't predict it's going to start raining when you're already getting wet. The evidence is in, GW is real and getting rapidly worse.

    How many degrees per decade again? And why is that considered "getting rapidly worse"? Global warming denying is not the only anti-scientific belief system causing waves here. The catastrophic climate change people are another such problem.

  • by hackus (159037) on Wednesday January 01, 2014 @05:49PM (#45840373) Homepage

    Stop Using Climate Change to disguise an argument about human based climate change.

    Nobody needs to argue that the climate changes.

    These globalists who want a revenue stream for world government employed on you, your kids via carbon taxes always use this stupid, really irritating title on this so called paid research of theirs on human climate change.

    Besides, I thought human based climate change was now a fact, and there wasn't any uncertainty?

    Meanwhile low temperature records world wide are in the lead 2 to 1 over heat record highs because the SUN has nothing to do with climate change.

    Globalist Climate Change Research = CRAP SCIENCE.


  • by citizenr (871508) on Wednesday January 01, 2014 @05:56PM (#45840429) Homepage

    2) You can prove them wrong

    Prove a negative? So far reality is proving them wrong.

  • by iggymanz (596061) on Wednesday January 01, 2014 @06:19PM (#45840613)

    we've just learned that there are huge reservoirs of unfrozen water under greenland ice sheet, and for the second year antarctic sea ice has reached a record high to the befuddlement of climate modelers (and a ship full of them is stuck in ice), and yet you make absurd statement as if we had completely accurate ice inventory.

    The models are failing, they didn't even account for the dominant greenhouse gas on earth, which is water and which is far too complicated to model with current technology. And linking to the stupid assertion #18 on about water vapor, based on a single event in the 90s, is not going to prove anything other than that only pseudo-scientific arguments from the "climatologists" exist on the subject.

  • by mbkennel (97636) on Wednesday January 01, 2014 @07:37PM (#45841265)
    "The models are failing, they didn't even account for the dominant greenhouse gas on earth, which is water and which is far too complicated to model with current technology. "

    The shameless ignorance is strong with this one.

    Do you really believe that climatologists have IGNORED water for 50 years? Oh, "oops we forgot it again"? WTF? It's like asserting that the entire profession of internal medicine forgetting that kidneys exist because they're "too complicated to model" and assume animals are all kidney and urine free.

    The very paper from the original article, peer reviewed and published in the top journal on the planet, is exactly about this very problem of testing which of the many climate models best deal with the complex feedback and feedforwards with water and clouds by using experimental data.

    Here's a hint. The people who do this for a living know much much much much more than you and I do about it. I have a modest idea how much more the pros know about it (I have a PhD in physics and am acquainted with the author) and I also have the feeling that in fact however much more I think they understand, they are probably even beyond that.

Q: How many IBM CPU's does it take to execute a job? A: Four; three to hold it down, and one to rip its head off.