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Earth Science

Reducing Climate Change Uncertainty By Figuring Out Clouds 249

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

    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.

    • As a physicist blithely dismissing another scientific discipline, you're a lousy physicist.
    • So is quantum physics, but that hasn't stopped a century of physicists from using statistical methods to work around the giant clusterfuck that lurks below the planck length.

      I had this exact same thing told to me by an undergrad physicist, so I pointed him at my sister who's a post-doc climate researcher and promptly schooled the guy on how its done (And pointed out to him why his knowledge of fluid dynamics was sorely lacking). He's not a skeptic anymore.

      For a less confrontational approach, go into your li

      • Saying that climate is chaotic and hard to predict shouldn't be controversial. It's pretty conceited to suggest that anyone who doesn;t agree with you needs to "read some of the research" and "come back with an informed opinion", when it appears that they themselves lack the informed opinion they require of others.

        Becoming informed is more than just reading X scientific journals espousing a certain conclusion, and changing your mind to that conclusion.

        If your sister has some valuable insight due to her exp

  • by Jah-Wren Ryel ( 80510 ) on Wednesday January 01, 2014 @05:28PM (#45839719)

    Fucking Clouds, How Do They Work?

    • They form unexpectatly. They rain down suddenly.
      So it is here when you look at it, and suddenly it's gone.

      They insulate. They also reflect.
      So which effect is bigger?

      While forming they are simply water vapour (a potent greenhouse gas).

      While forming they extract a great deal of heat out of the ocean. How much exactly depends on many factors, e.g. do they form over night or durin day time.

      • They form unexpectatly. They rain down suddenly.
        So it is here when you look at it, and suddenly it's gone.

        They insulate. They also reflect.
        So which effect is bigger?

        While forming they are simply water vapour (a potent greenhouse gas).

        While forming they extract a great deal of heat out of the ocean. How much exactly depends on many factors, e.g. do they form over night or durin day time.

        Thank you Sheldon Cooper!

      • The sun'll come out tomorrow

        Bet your bottom dollar that tomorrow

        There'll be sun!

    • by Mashiki ( 184564 )

      Fucking Clouds, How Do They Work?

      Why do we need to figure out how they work? The science is settled. [] And since it's settled we don't need to do anymore work.

      As noted previously, denying this for anyone in this thread makes you a climate change denier. Especially for those that have pointed out in the past that: We don't know how clouds operate fully in the biosphere, how much of an impact the sun has, total and partial fluctuations of various gravity effects, cosmic ray's and their impacts, and so on.

  • Models vs models (Score:5, Insightful)

    by cirby ( 2599 ) on Wednesday January 01, 2014 @05:42PM (#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.

    • Re: (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.

      • by khallow ( 566160 )

        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

        The problem is that 2) requires time. With sufficiently massaged paleoclimate data you can conclude just about anything. But it takes decades to gather high quality satellite data to confirm or falsify the claims made.

        • Which would be fine if people where "massaging the data". Fortunately theres no evidence of that.

          As my sister (A post-doc climate researcher) pointed out to me once , her profession is filled with tens of thousands of researchers desparately looking for that one piece of evidence that would show that the whole fields got it wrong and theres nothing to look for. Unfortunately in the century since scientists started worring about CO2 and infra-red, that evidence has failed to materialize.

          There is no conspirac

          • By "look for" read "worry about". The first guy that comes up with evidence that global warming isn't happening is going to get a Nobel Prize. And since Fourier first demonstrated CO2's greenhouse effects in the 1800s (And promptly started the scientific community flipping out about the greenhouse effect and the industrial revolution), nothing has arisen to demonstrate that the physics is wrong. Unfortunately to get that Nobel prize it would require some pretty massive evidence that some unseen mechanism is

            • by khallow ( 566160 )
              And this is an example of the anti-scientific attitude. You are obsessed over evidence for the existence of global warming (with a particular emphasis on certain oversimplified radiative models) as if it were the only way your belief system could go wrong.

              But global warming is not a binary state. I grant that there is compelling evidence for the existence of global warming. What I don't grant is that there is evidence that we need to do anything about global warming now.

              There are plenty of people with
            • You wouldn't have to show that all the thermometers are wrong. You would just have to accurately predict that the temperature of the planet would eventually go down, exactly when and by how much. If you could accurately predict climate, and your predictions show that it was going down, then you just disproved global warming. Maybe this still counts as climate change because the temperature went up a few degrees and then back down.

              All you'd have to show is that the recent increase in temperature was tempo

      • by citizenr ( 871508 ) on Wednesday January 01, 2014 @06:56PM (#45840429) Homepage

        2) You can prove them wrong

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

        • Proving someone wrong is not "proving a negative".

          If I claim that "all cats are black", all you have to do to prove me wrong is to provide evidence of a cat that is not black.

          If someone claims to know what the climate is going to be in the future, then they will get proven wrong if their predictions do not hold up. If their predictions are sufficiently vague, then they don't even need to be proven wrong to be dismissed.

      • The problem with models and predictions is that eventually you get to compare them to real world observations. They become accurate or inaccurate based on reality. If you want to enact social and economic change, you make sure your models predict catastrophe. You gobble up any funding provided to you, and use it to predict more catastrophe with more certainty. The problem is that reality will eventually intrude, and the game will be over.

    • Re: (Score:2, Interesting)

      by Immerman ( 2627577 )

      What are you talking about? Neglecting transient fluctuations (which are admittedly large enough to partially mask the still-small trend), global warming has been drastically worse that the worst-case scenarios predicted several decades ago predicted, probably in large part because human fossil fuel consumption has also been exceeding the worst-case scenario assumptions. Just because we haven't yet reached the predicted "apocalypse" doesn't mean we can't see it coming - it was never predicted to start to

      • Re: (Score:3, Insightful)

        by khallow ( 566160 )

        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.

        • That qualifies as getting rapidly worse because ecologies take time to adapt, and the rate of change is already exceeding anything in the geological record, including past climate changes events associated with widespread extinctions. And in case you hadn't noticed our ecology isn't currently doing all that great to begin with. Remember, if the bees all die, so do we. Ditto grass, and probably even sharks, etc.etc.etc. Anything that shoves the current ecology permanently out of balance is likely to caus

          • by khallow ( 566160 )

            and the rate of change is already exceeding anything in the geological record, including past climate changes events associated with widespread extinctions

            Like the asteroid impact that marks the end of the Cretacious? That climate change event probably took a fraction of a second to go from a rock in deep space to dinosaur ending fireball.

      • The changes in air temperature measurements have diverged from the changes in atmospheric CO2 measurements. I was promised that was not possible - a violation of basic physics. I was lied to.
    • Re:Models vs models (Score:4, Informative)

      by riverat1 ( 1048260 ) on Wednesday January 01, 2014 @06:26PM (#45840089)

      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. []

  • But I heard (Score:5, Funny)

    by Kohath ( 38547 ) on Wednesday January 01, 2014 @05:42PM (#45839813)

    "the science is settled".

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

    The science is settled: []

    • Re: (Score:3, Interesting)

      Good Science tends to be rather aware of its limitations.

      Bad Science Journalism tends towards dogmatic assertions of absolutism just as much as many religious folk.

      "Error bars", "p-values", "uncertainty values/ranges" are the norm in Science, not the exception.

      Here you're juxtaposing two separate issues. First "the science is settled" appears to be a remark or jab at the idea that the overwhelming consensus among relevant Scientists and relevant peer-reviewed studies is that global average temps are increa

      • by Anonymous Coward on Wednesday January 01, 2014 @06:28PM (#45840115)

        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.

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

        by Kohath ( 38547 ) on Wednesday January 01, 2014 @06:32PM (#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 mbkennel ( 97636 )
          Much of the very modest discrepancy has been located. It isn't in the models or the physics, but in the completeness and comprehensiveness of the data sets and the data reduction.
    • If you drop a feather it will hit the ground. The science is settled on that. Predicting the exact path the feather will take, now that's a much more complicated challenge.

      • wrong, a feather may fly upward due to thermal or wind, and may land somewhere off the ground. The science is not settled on that either

        • Where else will the feather land? In orbit around earth?

          Are we counting a patio or a roof or a lake as not "the ground"? I don't think Immerman was claiming that a feather will always land on a specific type of ground (e.g. soil), but rather that it can't stay in the air perpetually.

    • There are some big picture things about climate change that are settled. Changes in the level of greenhouse gases in the atmosphere affect the amount of energy stored internally in Earth's geophysical system. The increase in greenhouse gases in the atmosphere is primarily due to human burning of fossil fuels. Those and a few other things are pretty well settled. What isn't fully settled is lots of details that tweak the primary effects. This study is an example of that, comparing how different models h

      • That is the case with the big picture in climate science.

        Unfortunately it isn't, no. If it were, then you would have seen the warming trend continue past 1997. Unfortunately it's stopped even though CO2 has continued to increase. This is something of a problem for your hypothesis, isn't it, especially as we're now over half way through the standard 30 year period of significance.

        In my view, when people think something's settled and the real-world evidence flatly contradicts it, it isn't fucking settl

  • op all wrong (Score:4, Informative)

    by cinnamon colbert ( 732724 ) on Wednesday January 01, 2014 @06:24PM (#45840055) Journal

    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. []

    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

  • 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

    • by BoRegardless ( 721219 ) on Wednesday January 01, 2014 @07:57PM (#45840919)

      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.

      • by hey! ( 33014 )

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

        This is absolutely true -- over millions of years. It does not explain the warming trend in the past century. Your mode of argument is like saying "all will eventually die of old age, therefore automobile accidents don't kill people." There can be more than driver of climate change, and the timescale over which a driver of change operates is very important. Even if car accidents are less likely to kill you than old age, the fact that they kill you at 19 years old rather than 90 makes a big difference.


        • You are right that 4 degrees Centigrade over a hundred years might be bad for current citizens and that begs another question when it comes to food and water supplies.

          Given the world's climate change and the chance that it is cataclysmically caused by humans results in the question as to whether we have exceeded the number of humans that the earth can support in a stable manner.

          Try to get a resolution through the UN on that one to reduce population! Trying to reduce man made effects, like not enough water,

          • by sl149q ( 1537343 )

            Interesting conundrum. The left wing environmentalists want us to scale back on energy use, which effectively means we cannot support as many people on the earth as we have now. The alternative, they claim, is that doing nothing means we'll have problems growing enough food (due to climate change side-effects) to support the number of people we now have on the earth.

            So do something that condemns people to die of starvation NOW to prevent the possibility that people will die of starvation in the FUTURE, mayb

            • No one is claiming that we should do something that kills people to combat warming. We should use energy more efficiently and get energy from sources other than burning fossil fuels (e.g. solar, wind, nuclear, biofuels) to cut carbon dioxide emissions. We can do that and also support more people on the planet.

              I think misconceptions about what we plan to do to cut back on carbon dioxide emissions is the reason most people don't agree with cutting emissions... they think it means that they will have to do wit

  • Denialist Trolls (Score:4, Informative)

    by Daishiman ( 698845 ) on Wednesday January 01, 2014 @09:53PM (#45841951)
    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?
    • And just last week many were arguing that Slashdot style moderation would prevent these kinds of comments in online newspaper articles. When people have an agenda to push and the mainstream media won't do it for them, they'll do it for themselves in the comments.
    • by sl149q ( 1537343 )

      You mean like where the next IPCC draft has quietly cut the 30-year project of how much the world will warm from 0.4-1.0C (previous draft) to 0.3-0.7C in the final draft, also saying that warming is more likely to be at the lower end of the range over the next 30 years.

      • Yes, this is the kind of thing us denialist trolls have been saying for years: Sensitivity is far too high. Strangely, even though the IPCC itself has slashed its prediction, we're still called "denialists". It seems to me looking at the thread that it isn't the sceptics who're in denial here.
    • If you read the IPCC report, you'll find they slashed their measure of climate sensitivity. I expect it'll go down in the next one too, because let's face it they can't keep producing reports that contradict real-world observations, can they. Of course it's almost certain that you have not read the reports yourself.

How many NASA managers does it take to screw in a lightbulb? "That's a known problem... don't worry about it."