From DOE/LAWRENCE LIVERMORE NATIONAL LABORATORY
Clouds are impeding global warming… for now
Lawrence Livermore National Laboratory researchers have identified a mechanism that causes low clouds – and their influence on Earth’s energy balance – to respond differently to global warming depending on their spatial pattern.
The results imply that studies relying solely on recent observed trends are likely to underestimate how much Earth will warm due to increased carbon dioxide. The research appears in the Oct. 31 edition of the journal, Nature Geosciences.
The research focused on clouds, which influence Earth’s climate by reflecting incoming solar radiation and reducing outgoing thermal radiation. As the Earth’s surface warms, the net radiative effect of clouds also changes, contributing a feedback to the climate system. If these cloud changes enhance the radiative cooling of the Earth, they act as a negative, dampening feedback on warming. Otherwise, they act as a positive, amplifying feedback on warming. The amount of global warming due to increased carbon dioxide is critically dependent on the sign and magnitude of the cloud feedback, making it an area of intense research.
The researchers showed that the strength of the cloud feedback simulated by a climate model exhibits large fluctuations depending on the time period. Despite having a positive cloud feedback in response to long-term projected global warming, the model exhibits a strong negative cloud feedback over the last 30 years. At the heart of this difference are low-level clouds in the tropics, which strongly cool the planet by reflecting solar radiation to space.
“With a combination of climate model simulations and satellite observations, we found that the trend of low-level cloud cover over the last three decades differs substantially from that under long-term global warming” said Chen Zhou, lead author of the paper.
“The key difference is the spatial pattern of global warming”, said Mark Zelinka, LLNL climate scientists and co-author of the study. “Not every degree of global warming is created equal, in terms of its effect on low clouds.”
In response to increased carbon dioxide, climate models predict a nearly uniform warming of the planet that favors reductions in highly reflective low clouds and a positive feedback. In contrast, over the last 30 years, tropical surface temperatures have increased in regions where air ascends and decreased where air descends. “This particular pattern of warming is nearly optimal for enhancing low cloud coverage because it increases low-level atmospheric stability that keeps the lower atmosphere moist and cloudy”, said Stephen Klein, the third co-author.
“Most satellite data starts around 1980, so linear trends over the last three decades are often used to make inferences about long-term global warming and to estimate climate sensitivity,” said LLNL’s Chen Zhou, lead author of the study. “Our results indicate that cloud feedback and climate sensitivity calculated from recently observed trends may be underestimated, since the warming pattern during this period is so unique.”
Global temperature has gradually increased over the instrumental record due to increased greenhouse gas concentrations. But superimposed on this warming are large temperature fluctuations due to natural internal variability of the climate system, as well as influences from volcanic eruptions, aerosol pollution and solar variability. Whereas warming due to CO2 tends to be relatively spatially uniform, surface temperature trends due to internal climate variability and aerosol pollution are highly non-uniform, with trends on one side of an ocean basin often opposing those on the other. Trends computed over short time periods are often strongly influenced by factors other than CO2 and can be highly misleading indicators of what to expect under CO2-forced global warming.
The team emphasized that clouds are particularly sensitive to subtle differences in surface warming patterns, and researchers must carefully account for such pattern effects when making inferences about cloud feedback and climate sensitivity from observations over short time periods.
###
The work was funded by the Regional and Global Climate Modeling Program of the Office of Science at the U. S. Department of Energy (DOE) under the project “Identifying Robust Cloud Feedbacks in Observations and Models.”
The paper: http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2828.html
Impact of decadal cloud variations on the Earth’s energy budget
Chen Zhou, Mark D. Zelinka & Stephen A. Klein
Feedbacks of clouds on climate change strongly influence the magnitude of global warming1, 2, 3. Cloud feedbacks, in turn, depend on the spatial patterns of surface warming4, 5, 6, 7, 8, 9, which vary on decadal timescales. Therefore, the magnitude of the decadal cloud feedback could deviate from the long-term cloud feedback4. Here we present climate model simulations to show that the global mean cloud feedback in response to decadal temperature fluctuations varies dramatically due to time variations in the spatial pattern of sea surface temperature. We find that cloud anomalies associated with these patterns significantly modify the Earth’s energy budget. Specifically, the decadal cloud feedback between the 1980s and 2000s is substantially more negative than the long-term cloud feedback. This is a result of cooling in tropical regions where air descends, relative to warming in tropical ascent regions, which strengthens low-level atmospheric stability. Under these conditions, low-level cloud cover and its reflection of solar radiation increase, despite an increase in global mean surface temperature. These results suggest that sea surface temperature pattern-induced low cloud anomalies could have contributed to the period of reduced warming between 1998 and 2013, and offer a physical explanation of why climate sensitivities estimated from recently observed trends are probably biased low4.
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“relying solely on recent observed trends are likely to underestimate how much Earth will warm due to increased carbon dioxide”
the relationship between atmos co2 and surface temperature even in the recent data (actual measurements and not reconstructions) appears to be sensitive to the sample period chosen.
the way around that is to use resampling as demonstrated here:
https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2861463
They are simply lying to themselves. The predictions are wrong, so they explain away reality. Pathetic climate fanatics.
Yes, they are truly deluding themselves at this stage; amazing how they twist things so they can have it both ways – when there’s warming, it’s because of CO2; when there’s not, the Co2 induced warming isn’t going to be seen until some distant future time (conveniently). So which one is it?!
They are simply lying to themselves. The predictions are wrong, so they explain away reality. Pathetic climate fanatics.
GCMs are both better and worse than they are given credit for.
I was at a talk yesterday about the Antarctic sea ice anomaly:
every single CMIP5 model says that Antarctic sea ice is decreasing,
but it’s increasing.
The speaker said that the group he was in (which I think was basically him and his supervisor) looked at the physics, and asked “how do the models handle the ice shelves”? Turned out that all of the existing models ignored the Antarctic ice shelves completely. They added the ice shelves (and the energy budget for meltwater) to one of the models, and presto chango, the model now showed increasing sea ice, at roughly the way the world had really been.
This says to me that for the things the models include, they are not without merit, BUT that as you might expect, it’s the FIRST step of modelling where you decide what to put in your model and what to leave out where the big errors start.
If I remember correctly, the speaker said that it took 4 days per simulated year
on the supercomputer they were using, and they were simulating the last 30 years. I think he said they were using 1 km square cells with 60 layers for the ocean and 30 layers for the atmosphere, and that the model they were starting from was a million lines of Fortran. These are not things that are easy to work with. Getting the grid down to the scale where you can model clouds well is going to push the state of the supercomputing art.
Richard A. O’Keefe commented : “…Fortran… supercomputing….”
Non sequeter
A million lines of Fortran? I can just about guarantee you there are ten unrecognized serious errors in that program.
“… BUT that as you might expect, it’s the FIRST step of modelling where you decide what to put in your model and what to leave out where the big errors start.”
Back in the day when I was a practicing engineer, we had a rule of thumb that all the truly bad decisions on a program were made in the first 10 minutes (comparable to that first step of modeling).
A model with a million lines of code is not a model of anything but nonsense and most like hardcoded to calculate a predefined result (thus the million lines of fortran code – nobody will ever be able to code review or QA it) easy to hide in that much noise …
I think rgb-at-duke estimated that computing power would need to increase by 6 orders of magnitude to accommodate a sufficiently detailed model where you could start thinking about getting something useful with regard to climate. Think quantum computers.
I hope someone can confirm this.
Some 15 years ago, purple onions were mild. Nice flavour and mild.
Now they are much hotter.
Must be due to global warming.
maybe your tastebuds have changed?
Worse than we thought.
Headline: “Global Warming Makes Taste Buds Angry”
Climate models predict nothing, they project. Projections are much better, than predictions, because, due to their wonderful malleability, they can never be falsified by observations. Therefore they are always true. Not.
I could have sworn that they used to claim that there would be more warming at the poles than in the tropics, due to the distribution of H2O in the atmosphere.
Now CO2 is supposed to have a uniform affect?
Maybe the clouds that are “impeding global warming”, are caused by global warming (sarc).
;
“…..the trend of low-level cloud cover over the last three decades differs substantially from that under long-term global warming”
So we will disregard what we have observed over the past 3 decades and put our trust in the climate models????? Un-be-lievable!
Yes, that was the bit I reacted to as well. Basically, these were wrong type of clouds therefore we can ignore their effect and when the right type of clouds come back, it will get hotter as the models predict, no, sorry, project.
Google “wrong type of snow” for more hilarity.
Post hoc rationalizations. A clear sign of pseudo science.
Any warming will result in more convection. Heat is removed from regions where the air is moving upward. The air is cooled in the upper atmosphere and cools the region where it moves downward. Surely that is unsurprising.
The increased convection is a negative feedback. It should be pretty linear and should be reliable over all timeframes. I think these researchers have misinterpreted their own evidence.
Of course they have – because they begin with the erroneous ASSUMPTION that increased CO2 level pushes the temperature up, when all the “theory” (really just hypothesis) ever said is that “ALL OTHER THINGS HELD EQUAL, doubling the atmospheric CO2 content would increase the average temperature by about 1 degree Celsius.” But all else isn’t held equal, and the feedbacks are negative, and the real world CO2 effect is for all practical purposes nil.
Catch up will you, this is your job….
http://www.newclimatemodel.com/new-climate-model/
Just goes to show it’s always even worserer than we thunk.
As Roseann Roseannadanna said “It’s always something.”
There will never be an admission they were wrong. If temperatures drop over the next 40 years by 4C , the response will be “Ya but it would have dropped by 7C without AGW.”
It doesn’t matter what the observational data show. The automatic response will be that it would have been colder.
Combine this with the clean air acts reducing SO2 which is a cloud nucleator and so letting more insolation in what has been the actual warming caused by CO2?
Same as always…essentially nothing. CO2 has been uncorrelated with temperature, lagging behind but correlated with temperature, and reverse correlated with temperature on geologic time scales. In terms of temperature, CO2 “drives” two things – Jack and “Ship High In Transit.”
From my perspective , considering the state of energy technology, and usage to be expected in the fairly near future (sometime this decade), all debate annd fighting over CO2 emissions simply reflects extreme ignorance of what lies ahead, which will prevail regardless of the actions of the advanced Western nations. Points of fact : 1) GM announces that it is paying $150 per kWhr for the lithium batteries it will be installing in its electric cars ths year 2) Tesla Motors announces that it will be paying $190 per Kwhr, which pays for all of the costs of the battery pack, not just the cells, 3) Elon Musk claims his battery “gigafactories” can cut battery costs by a third 4) lithium automotive battery packs can be recharged to 80% in around 20 minutes. 5) Molten salt nuclear reactors can be built very quickly in factories and installed with minimal site preparation and will produce power for less than 2 cents per kWhr, making it the cheapest (and safest) power producer on the planet, and can burn nuclear wastes as fuel, reducing them to relatively low radioactive residues which will return to background radiation levels in less than 5 generations and are cheapy stored till that time.
Battery prices are close to the point where gas powered cars become obsolete as overly complicated and expensive compared to more reliable electric versions, and the promised cost reduction by a third gets them there.
I have faith that the sheer economics of the coming technological changes described will force their adoption, although probably adoption will occur more rapidly in China and other Asian countries first. As usual, Western nations will continue to trail in manufacturing and adoption of new power generation technologies due to political pressures that are stupid, although southeastern states in the U.S may buck this trend, as they are doing at present thru the only new nuclear power construction in the nation and their ability to attract manufacturing.
I consider therefore the war on CO2 emissions to be stupid and pointless and a use of energy and money that should be spent encouraging development advanced technologies. It is criminally insane to pour money into things like wind and solar, destined to be non-sustainable economically
in the face of coming energy technologies. I predict a healthy business removing wind turbines
in the fairly near future. And solar roofs will not be replaced when their solar cells weaken in 20 years or so.
If any of the links in that quite improbably chain of events actually happens, let me know.
The biggest problem with batteries is lack of range and cost of replacement.
The first hasn’t been solved and the second is only marginally impacted by these improvements, assuming they actually occur.
I’d agree with your assessment of the problems with battery based electric powered transport, not to mention the more frequent need for charging (equivalent to fueling) which takes 4-5 times as long and is therefore an impractical nuisance. Make your trip at night or in heavy traffic or foul weather and those issues are all magnified.
All of this, of course, also fails to mention the amount of environmental destruction done in the mining of “rare Earth metals” needed for all that battery production, the resources that will be expended on disposal of spent batteries (whether the materials can be recycled or otherwise), and the inefficiency of hauling around the weight of the battery packs, which isn’t reduced as their range is depleted as is the weight of a tank of liquid fuel.
If electric vehicles are going to displace ICE vehicles, the roads will have to have an electric power system that the vehicles can draw electricity from built in.
The biggest problem with batteries for vehicular transport is low energy density. To carry enough batteries to get a decent range, you make the vehicle very heavy, reducing the range meaning more batteries – and so on. All other problems flow from this. The only place electricity has a major role in transport are electrified trains/trams which don’t need to carry your energy with you. Until energy density gets up somewhere near liquid fuels you can forget it as a serious challenge to current vehicles as it is too wasteful of the energy itself.
Rob, don’t forget golf carts.
Nice one, Mark.
Think how terrible it is when your golf cart runs out of power on the 16th fairway! Somebody should do something about this!
and another example of how the human brain just cannot ‘get its head around’ feedback systems.
For humans, something always has to cause something else – the human mind is compelled to break open the/a/any feedback system to try and understand its workings and in doing so destroys the very thing its looking at.
This whole thing about LWIR and temperature.
Things with temperature radiate – they cannot do anything else. Temperature is radiation, radiation is temperature. You cannot say one causes the other. Not least, if the object with temperature wasn’t radiating, you couldn’t see it. It wouldn’t be there.
Of course where the simple minded human brain gets confused is with the sun radiating and causing the place to warm up. Think about the difference between the dirt you’re standing on and the sun.
An example from Buddhist teaching (Thich Nhat Hanh) He will use the example where people might say “The rain is falling”
But if rain is not falling, its not rain. So, what causes what? Does rain cause the falling or does the falling cause the rain? So it is with radiation and temperature.
Again with clouds and temperature. Folks may notice it seems warmer (esp at night) when its cloudy and in their eagerness to show how clever they are, tell everyone that the clouds are trapping radiation or radiating warmth down to the ground.
Good fooking grief, how is a cloud, say 1,000m above your head and hence 10’C colder than you, going to warm you up? No more than replacing your living room fire with an iceberg will. The iceberg has temperature, it radiates, so why doesn’t it warm your house? Yet we all swallow this garbage.
Cold objects cannot radiate to warm objects so as to raise the temp of the warmer object
Clouds seem to warm you simply because you’ve been overtaken by a big bubble of warm air that’s rolled in from somewhere else. As if the higher temperature didn’t tell you that, a cloud forms where that warm air meets colder air above you. (See how this pathetic understanding of feedback gives totally the wrong answer/understanding) Warmth causes the warmth and also the clouds.
Clouds don’t cause warmth, they are a side-effect of warmth.
The cloud is not trapping radiation. Nothing can trap radiation. Not least because (electromagnetic) radiation is a moving thing, a variation/change of electric and magnetic fields at right angles to each other that moves through space at right angles to that.
It cannot be trapped because no-one has yet puzzled how to trap change.
What we’d need would be a Flux Capacitor (change store) – the very heart of any and all time machines and such devices patently don’t exist. And because they don’t exist now, they never have and they never will.
That’s not insight, it’s word play.
It’t the sound of one hand crap.
Please, son of mulder, use the proper technical language. It’s called pseudo-profound bullshit.
@ur momisugly Peta in Cumbria:
I think you’re confused. Clouds at night don’t warm you up, they slow down the rate at which you cool. A cloud might be 10 degrees cooler than you are but the alternative radiation target would be space which is only a few degrees above absolute zero. According to your way of thinking, a coat wouldn’t keep you warm because it’s cooler than you are. Coats, clouds, duvets – they’re all just insulation.
“Trends computed over short time periods are often strongly influenced by factors other than CO2 and can be highly misleading indicators of what to expect under CO2-forced global warming.”
Correct me if I’m wrong (which I probably am), but, aren’t they implying an expectation that clouds will somehow stop having the effect they have for the last 30 years at some time in the future, for reasons as yet unknown? Seems to me that is the only reason they can say that climate sensitivity is underestimated during the last 30 years. Bill Parcells, a great (American) football coach maintained, “you are what your record says you are”. Applying that logic, climate sensitivity is what it says it is, it can’t be ‘impeded’ by a negative feedback unless that feedback will stop at some time in the future. Isn’t this a tropical cloud version of ‘the missing heat is in the deep oceans and when it comes out it will be bad’ theory?
Basically, they’re showing that their so-called “science” is nothing more than pseudo science, because they refuse to accept observations that contradict their preconceived conclusions about CO2 driving temperature.
First. just want to note that it is difficult to tell if they used actual data in this study or just climate model simulations. You can’t really tell.
Second, the CERES satellite is showing that the Cloud Radiative Effect (cloud forcing) has indeed declined since the year 2000. Shortwave solar reflection has remained fairly stable but the long-wave heat-held-in forcing has declined. Overall the Cloud Radiative Effect has increased from -21 W/m2 to about -22 W/m2. The anomaly shown here -1W/m2 change (on top of the ERBE satellite showing something similar prior to 2000).
Overall, however, CERES is not showing any change at all in the Earth Radiation Budget. (Clear Sky is up a little and Cloudy Sky is down a bit). Net Zero overall. Where’s the predicted changes?
But let’s say, this study and the CERES and ERBE satellites (and Willis) are right, that the Cloud Feedback is something like -1.0 W/m2/K (rather than +0.7 W/m2/K in the theory and in the IPCC and in Hansen needing to get to get to 3.0C per doubling therefore all feedback assumptions are carefully chosen to get there rather than measured.
… Global Warming then falls to 1.373C per doubling when calculated with -1.0 W/m2/K Cloud Feedback. Not much to worry about.
Sooner or later, Svensmark will be acknowledged as a visionary.
It’s always fun when Alarmists “discover” what we’ve always known. And then in their charming way, completely misinterpret what they’ve “discovered”.
[Expletiving] clouds interfere with “normal” feedback?
“over the last 30 years, tropical surface temperatures have increased in regions where air ascends and decreased where air descends”
See here:
http://joannenova.com.au/2015/10/for-discussion-can-convection-neutralize-the-effect-of-greenhouse-gases/
Fig 3 shows how, after CO2 has done its work in distorting lapse rate slopes, the surface temperature is warmer than it otherwise would have been below ascending columns and cooler than it otherwise would have been beneath descending columns.
Exactly as observed according to the above paper.
The net effect for the system as a whole being zero.
Which should surprise nobody when you look at the sometimes uncorrelated, sometimes correlated with temperature change leading CO2 change, and sometimes reverse correlated CO2 vs. temperature on geologic time scales. IOW, CO2 doesn’t “drive” temperature, at all, in Earth’s climate history, so why should it suddenly have a power it didn’t have in the past today?!
Does the model include the diurnal cycle of thunderstorms? That is, thunderstorms in the daytime, reflecting energy, clear skies at night radiating energy. I suspect the models don’t model anything that happens on such a short timescale.
Models don’t handle anything smaller than about 100 miles square. Thunderstorms are way to small to be modeled. So they are parameritized instead. Which just means the modelers tell the model how the clouds would have behaved, had the model been able to handle them. (Of course, they are modeling their assumptions, but they will never admit that.)
So the missing heat is no longer hiding in the deep ocean, it’s now hiding in negative feedbacks?
I can’t resist, besides it has just as much as scientific, and more aesthetic, value:
Darn, you beat me to it!
But now they only block the sun
They rain and snow on everyone
So many things I would have done
But clouds got in my way
Feedback bias… Or BS?