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Reducing Climate Change Uncertainty By Figuring Out Clouds

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."

17 of 249 comments (clear)

  1. Insane Cloud Posse by Jah-Wren+Ryel · · Score: 3, Funny

    Fucking Clouds, How Do They Work?

    --
    When information is power, privacy is freedom.
  2. Models vs models by cirby · · Score: 5, Insightful

    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.

    1. Re:Models vs models by flaming+error · · Score: 3, Insightful

      "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.

    2. Re:Models vs models by riverat1 · · Score: 3, Informative

      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.

      The study "assumes" nothing of the sort. It compared the differences in the way different climate models handle water vapor and cloud formation and found the ones that dry out the lower atmosphere more quickly do a better job of modeling real world observations.

      As far as all climate models being wrong that probably has more to do with your misunderstanding of what climate models are designed to do than it does with the climate models themselves. As George Box said "All models are wrong but some are useful." Climate models are at best crude representations of the atmosphere, partly because it's impossible* at this point to model things on a small enough scale to capture everything, but they're still better than any other method we have.

      *Impossible because of limitations in computing horsepower. Current models use grid scales of around 100 km x 100 km x 1 km vertical x 30 minutes per step.

    3. Re:Models vs models by citizenr · · Score: 4, Insightful

      2) You can prove them wrong

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

      --
      Who logs in to gdm? Not I, said the duck.
  3. But I heard by Kohath · · Score: 4, Funny

    "the science is settled".

    How can there be any uncertainty when "the science is settled"?

    The science is settled: http://www.npr.org/templates/story/story.php?storyId=9047642

    1. Re:But I heard by Kohath · · Score: 4, Insightful

      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.

  4. Re:First thing they need to do by Em+Adespoton · · Score: 4, Insightful

    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).

  5. op all wrong by cinnamon+colbert · · Score: 3, Informative

    the abstract doesn't say they used data, it says they identified a math procedure that caused variation between the models

    so, what you have are a lot of complex computer models that vary in output; the authors show that about half the variation is due to cloud mixing
    however, we have no idea if the models are in fact accurate, other then Fig 1b of Fyfe etal, which suggests that the models are in fact NOT accurate, so it doesn't matter if you lower the variation between them.
    http://www.see.ed.ac.uk/~shs/Climate%20change/Climate%20model%20results/over%20estimate.pdf

    I would remind people of history: in the early 1800s, people realized that CO2 absorbs IR, and the late 1800s, they realized that humans were actually putting out enough CO2 to make a diff
    Then, around 1900, someone pointed out that the atmosphere is optically thick in the IR (if you could see the color "IR" it would be pitch black all the time), so an increase in CO2 shouldn't matter
    This *scientific consensus* lasted untill the 1950s, when people realized that it is emission from the outer atmosphere that matttrs....

    so, for 50 years, there was a consensus that CO2 human warming was hooey

  6. IPCC AGW predictions FAILED by Anonymous Coward · · Score: 4, Informative

    Graph shows 1990 IPCC predicitons with REALITY. There is a range of values predicted by the IPCC and the "settled consensus of climate scientitst" and then there is reality which isn't in the range they selected. They are WRONG, 100% WRONG. They made their predictions, gave a range, told everyone to stop debating, and were wrong, period.

    Go ahead back to your church of AGW and keep tithing and singing hymns or whatever else you do there. The rest of us used failed scientific predictions as PROOF they were wrong.

    Spin away at those facts. Attack me, attack the graph, pretend I didn't post this, whatever. The fact remains the IPCC FAILED no matter how you want to try and look at it.

  7. Re:Kelvin the Earth? by Em+Adespoton · · Score: 3, Funny

    Who knew the Earth's name was Kelvin?

    Oh.

    It's all just a matter of degree....

  8. "Paid" by cirby · · Score: 4, Informative

    Those "record breaking massive storms" were, overall, not much worse than average. A couple of large ones, but they got large mostly because there weren't that many medium-sized storms along their paths. Meanwhile, we didn't seeing much of anything in the Atlantic (record-breaking "dud"), and areas outside of that one patch of Pacific Ocean were pretty average.

    On the "paid" issue:
    You do realize that even the guy who wrote that study you mention says that the reporter who wrote the story pretty much lied their ass off, right?

    The short form: The actual study took any group that published anything at all that might, maybe, sorta could question AGW. Even one article or study. Then they took the entire budget of each organization and added it up. That's how they got that $900 million plus.

    The actual amount that could actually, sorta, maybe be tied to anti-AGW funded studies or articles? About enough to fund Greenpeace for week and a half. If you counted things like studies showing that people don't like paying extra taxes for green energy stuff that doesn't actually work.

    On the other hand, the "green" businesses are funding all sorts of sketchy "science" to support their industries. Like the guy who makes money off of "carbon remediation," who funded the really stupid "expedition"/tourism group that's currently being evacuated from their ice-trapped Russian ship.

  9. Re:Human Based Climate Change vs Climate Change Ti by BoRegardless · · Score: 3, Informative

    Sorry, but the Sun has everything to do with climate change when combined with the variable orbit geometry of the Earth around the Sun.

    We will reenter the next ice age and Canada will again get covered by a kilometer or two of ice and all existing shipping harbors will become dry land.

    It will probably take another 50,000 years, but it will happen on the 110,000 year cycle that has repeated at least a couple dozen times now.

  10. Re:Chemtrail are working by mbkennel · · Score: 5, Insightful

    "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.

  11. Denialist Trolls by Daishiman · · Score: 3, Informative

    Holy crap since when did /. get overrun by denialist trolls that just don't read articles, and obviously fail to even read the IPCC reports?

  12. Re:There is no uncertainty by bunratty · · Score: 3, Informative

    Shaky grounds? Carbon dioxide is a greenhouse gas. Greenhouse gases cause warming. We are emitting billions of tons of carbon dioxide each year into the atmosphere. The warming caused by these emissions was predicted over 100 years ago. We are now observing that predicted warming. Which one of these is the least bit shaky?

    I don't understand what you mean about no uncertainty. There is always some uncertainty in science. No measurement is ever exact, and science never proves anything beyond a shadow of a doubt.

    --
    What a fool believes, he sees, no wise man has the power to reason away.