New tool clears the air on cloud simulations
LIVERMORE, Calif. — Climate models have a hard time representing clouds accurately because they lack the spatial resolution necessary to accurately simulate the billowy air masses.
But Livermore scientists and international collaborators have developed a new tool that will help scientists better represent the clouds observed in the sky in climate models.
Traditionally, observations from satellites infer the properties of clouds from the radiation field (reflection of sunlight back into space, or thermal emission of the planet). However, to accurately utilize satellite data in climate model assessment, a tool is required that allows an apples-to-apples comparison between the clouds simulated in a climate model and the cloud properties retrieved from satellites.
“The models are becoming more interactive and are taking into account the radiation data from the satellite observations and is an important part of the process of making better climate models,” said the Lab’s Stephen Klein, who along with LLNL’s Yuying Zhang and other collaborators have developed the Cloud-Feedback-Model Intercomparison Project Observation Simulator Package (COSP).
“The models have been improving and refining their representations of clouds and COSP will play an important role in furthering this improvement,” Klein said.
Climate models struggle to represent clouds accurately because the models lack the spatial resolution to fully represent clouds. Global climate models typically have a 100-kilometer resolution while meteorological models have a 20-kilometer range. However, to accurately represent clouds as seen in satellite measurements, the scale would need to be from the 500-meter resolution to 1-kilometer range.
“But those small scales are not practical for weather or global climate models,” Klein said. “Our tool will better connect with what the satellites observe – how many clouds, their levels and their reflectivity.”
The COSP is now used worldwide by most of the major models for climate and weather prediction, and it will play an important role in the evaluation of models that will be reviewed by the next report of the Intergovernmental Panel on Climate Change, Klein said.
The COSP allows for a meaningful comparison between model-simulated clouds and corresponding satellite observations. In other words, what would a satellite see if the atmosphere had the clouds of a climate model?
“COSP is an important and necessary development because modeled clouds cannot be directly compared with observational data; the model representation of clouds is not directly equivalent to what satellites are able to see,” Klein explained. “The COSP eliminates significant ambiguities in the direct comparison of model simulations with satellite retrievals.”
COSP includes a down-scaler that allows for large-scale climate models to estimate the clouds at the satellite-scale. The tool also allows modelers to diagnose how well models are able to simulate clouds as well as how climate change alters clouds. The tool already has revealed climate model limitations such as too many optically thick clouds, too few mid-level clouds and an overestimate of the frequency of precipitation. Additionally, COSP has shown that climate change leads to an increase in optical thickness and increases the altitude of high clouds and decreases the amount of low and mid-level clouds.
Other collaborators include: the UK’s Hadley Centre, Université Pierre et Marie Curie; University of Washington; Monash University, University of Colorado; and the National Oceanic and Atmospheric Administration/Earth System Research Laboratory.
More information about the COSP appears in the August issue of the Bulletin of the American Meteorological Society.
More Information
“Increase in atmospheric moisture tied to human activities,” LLNL news release, Sept. 18, 2007
“Identification of Human-Induced Changes in Atmospheric Moisture Content,” Proceedings of the National Academy of Sciences, Sept. 25, 2007
LLNL’s Program for Climate Model Diagnosis and Intercomparison
Your headline is completely misleading. COSP is a tool for assessing the clouds that are already in the model, not for changing the way the clouds are dealt with. It is important because it means that model output can be compared directly to satellite products that have very specific ways of looking at what is going on. Why is so hard to accept advances without the snark?
REPLY: OK, don’t bother, they’re here
Dan, please point out the snark…I must have missed it.
So now we have an admission that climate models do not accurately reflect the role of clouds. That is progress.
Unfortunately two of the links keep banging on about human induced water vapour – the dreaded CO2 feedback scenario.
Never mind the natural temperature variations caused by…so many things I can’t be bothered to list them – that in themselves will push water vapour levels up or down.
But every little helps, and we may even see one day the admission that despite the models, NOTHING MUCH HAS CHANGED.
I think I’m missing something. We now have a model that predicts cloud conditions under future projected conditions that may not yet exist. How do we know the model is accurate at producing these projected conditions? Sounds like models all the way down.
What about the convection that forms the clouds. Will that be modeled as well?
I expect not, and so the warm air carried above the greenhouse will still not be accounted for.
Away with the gamers.
dan says:
October 27, 2011 at 8:27 am
Superb response, Anthony, could not be improved on. Perhaps we need a new blog for the, what is the PC term, oh, yeah, “humor-challenged” among us.
dan, the titles on the posts here at WUWT tend towards the whimsical. I like that, it is much more fun than the dull titles of most posts. They often are a play on words, or refer to some historical event or famous quote. My recent post on the coral reefs was entitled “The Reef Abides”, a somewhat cryptic reference to the film “The Big Lebowski”.
This, of course, means that often there is not a one-to-one relationship between the titles and the content of the respective posts. And I’m sure that someone like yourself could point out that the reef doesn’t really abide, it changes all the time, and some reefs disappear, and as a result my title is not scientifically accurate … so what? It’s a post title, for goodness sake, not a guide to the scientific secrets of the subject matter.
w.
well said Willis I always like reading your writing even if it is a comment in a thread.
So what they’re saying is they’ve looked at clouds from both sides now…
LMAO,
That could not have been better cued. Thanks for the chuckle Anthony. When do we get to see the jugglers?
Dan-
It might not square with your preconceptions, but any “snark” is in the original press release. You may apologize now.
I’ve looked at clouds from both sides now.
From up and down, and still somehow.
It’s cloud illusions I recall.
I really don’t know clouds at all.
(Joni Mitchell, 1968)
Willis Eschenbach says (October 27, 2011 at 11:01 am): ‘My recent post on the coral reefs was entitled “The Reef Abides”, a somewhat cryptic reference to the film “The Big Lebowski”.’
Huh. I took it as a reference to a novel:
http://en.wikipedia.org/wiki/Earth_Abides
Perhaps someone, somewhere, no understand Sondheim song.
They have to look towards the clouds now with it not going to plan, can only ignore the obvious for so long.
Well unless these new and improved cloud model simulation guesstimates deal FIRST with the REAL CLOUD FEEDBACK; which is the relationship that shows how MORE CLOUDS result in LESS SURFACE SUNLIGHT and how LESS CLOUDS result in MORE SURFACE SUNLIGHT, then it is TOTALLY IRRELEVENT how they THINK MORE CLOUDS, affect SURFACE EMITTED lwir.
So deal FIRST with the huge negative feedback from cloud increase to solar energy decrease (AT THE SURFACE: AKA OCEANS). The effect on LWIR from the surface is almost inconsequential by comparison to the PRIMARY FEEDBACK TO THE MAIN CLIMATE DRIVER; AKA THE SUN.
Well when I want to see what is in somebody’s back yard; I do not go around to their front yard and try to look right through their house.
Likewise, if I want to know how much solar energy is reaching the ground (oceans) under the clouds; I do not go up on top of the clouds and look down.
Get it !! your look UP to see what’s COMING DOWN, and you look DOWN to see what’s COMING UP. it’s 4-H club science.
George E. Smith; says:
October 27, 2011 at 1:48 pm
Well when I want to see what is in somebody’s back yard; I do not go around to their front yard and try to look right through their house.
_________________________
So George has admitted to being a peeping tom, while this is a bit scarey I do like the analogy. Well said, even my simple mind can grasp that!
Willis Eschenbach says:
October 27, 2011 at 11:01 am
Note that whimsical titles make it a bit harder to find articles when scanning my monthly and category summaries at my Guide to WUWT. http://home.comcast.net/~ewerme/wuwt/index.html . The art is to come up with a whimsical title that conveys enough information to the person scanning the list of titles.
Maybe there are some hot clouds up there hiding the heat. Somebody tell Trenberth.
http://www.itnews.com.au/News/260814,microsoft-eyes-cloud-waste-for-home-heating.aspx
http://www.physorg.com/news/2011-09-ice-cold-clouds.html
http://paintoutings.blogspot.com/2009/08/heat-clouds.html
“The tool also allows modelers to diagnose how well models are able to simulate clouds as well as how climate change alters clouds. ……..has shown that climate change leads to an increase in optical thickness and increases the altitude of high clouds and decreases the amount of low and mid-level clouds.”
Wow…the model has told us all this about dynamics like clouds…and the cause ….climate change, of course.
I am sure once all the models have been adjusted we will find…its worse than we thought!
Hansen, Mann, Jones, Trenberth, and their benighted acolytes forget that since 1890 the rebound from a 500-year Little Ice Age (LIA) has progressed in cycles of ever higher frequency, shorter wavelength. Following a 30-year warm-phase from c. 1980 to 2009, the current 20-year period from c. 2010 – 2029 represents an ultimately short-term chill presaging not merely a 70-year “dead sun” Maunder Minimum similar to that of 1645 – 1715 but an overdue resurgence of 102,000-year Pleistocene Ice Time.
Absent the 1,500-year Younger Dryas “cold shock,” which reset the Holocene Interglacial’s 12,250-year median projected time-frame, Earth’s Long Summer would have ended coincident with the Roman Warm about AD 450. As it stands, the Holocene began to peter out in 1950. All the Green Gang’s fancy-dandy measurements and self-serving models cannot put this post-glacial interstitial epoch together again.
Gary Hladik says:
October 27, 2011 at 12:39 pm
I’d say you are right as well. I always figured that “The Dude Abides” was a play on “The Earth Abides”, one of the favorite novels of my childhood. That’s why it was so funny to me.
w.
Ric Werme says:
October 27, 2011 at 2:47 pm
Tru dat.
I’ve kinda backed off after I couldn’t find some of my own work by the title … but I haven’t backed off too far. Buddha recommended the middle path …
w.
I wonder if the climate hippies can’t model clouds, not because they can’t accurately model anything else, but because it gives them flashbacks.
There be the hippie climatologist confused as ever, getting down and his hands charcoaled coated by dabbling in the strange field of mathematical modeling, trying to include clouds into his new found reality. The mere thought of clouds, though, make him look up, into the skies, a longing look coming into his eyes, looking far and far away, a look that has seen better, happier days, spent puffing the bong. At the third imaginary puff his eyes go wide, in an exact historical mock up, and he goes:
eeek 0_o M A G I C D R A G O N S! We’re doomed, we’re doomed.
After they work on the clouds, will they then get on to Humidity. From their report
Upper-tropospheric humidity. As an example of RTTOV diagnostics, we use uppertropospheric
humidity (UTH; Fig. 8). UTH is a key climate variable that plays a very important role in
Earth’s radiation budget (e.g., Kiehl and Briegleb 1992; Ingram 2010). However, UTH is not well simulated by current climate models (Pierce et al. 2006; John and Soden 2007).
http://journals.ametsoc.org/doi/pdf/10.1175/2011BAMS2856.1
Send in the clowns… delete delete delete… clouds.
It IS a great advancement for Climate Science; now they’ll have better explanations for why reality needs adjustment to the models.
You should perhaps acquaint yourself with realclimate, who have been saying that consistently, and have explained in some detail the shortcomings and occasional advances with cloud modelling. Or check out the IPCC report, which spends time time talking about the advances and problems with cloud modelling – chapter 8 on models has a lot on that sub-topic.
Real skepticism is omnidirectional. Just because something is said (or jokingly implied) at WUWT, doesn’t make it true.
@henrythethird : I swear I hadn’t read your comment… It was probably still “awaiting moderation” when I posted mine anyway… Shall we say that great minds think alike?
So then a new type of Holy Divination is to be used? How else can a “computer model” predict random chaotic events that have not yet, and may not even happen? Events, such as condensation of water vapour into droplets, and back again, and whether they precipate or not (if indeed they existed at all), at some specific location or area of the planet.
Sounds like hokum and gimcrackery to me.
Barry, it is true that Realclimarte, and for that matter the IPCC reports such as AR4, and many papers by mainstream climatologists, have repeatedly stated that the role of clouds is not yet fully understood. However, when making projections based on models (based themselves on a poor understanding of clouds) the above acknowledgment of ignorance is not fully taken into account. A better understanding of clouds may potentially have an enormous effect on estimates of climate sensitivity, basically introducing a potentially large negative feedback into the equation. Thus these new developments providing more knowledge about clouds and pointing in exactly that direction are worth remarking. When one sees the next model projection of global warming due to CO2 emissions, a sign reading “Clouds ahead – Use your grain of salt” should be visibly displayed.
Hector, IPCC climate sensitivity has a range that is the same size as the mean estimate. The projections accordingly have a wide range, widening the further forward in time. For any given emissions scenario, the range is about -40% – to +60% of the mean estimate out to the late 21st century. Uncertainties like clouds are included in the range. There is no need for bumper stickers – the uncertainties are discussed at length in the IPCC report.
These things are not neglected is all I’m saying. If you think, like Richard Lindzen, that IPCC doesn’t allow enough range for cloud (or other) uncertainties, then that’s a different, more technical conversation (which I am completely unqualified to attempt).
All else having failed to date, now they are going to try to hang the blame of their statistical generated global warming on poor puffy cloud, letting the repeating offender UHI off the hook scott-free. Do these alarmist climatologers have no shame?
Anthony writes “REPLY: OK, don’t bother, they’re here”
You couldn’t buy a better “article heading -> response -> response to the response” 🙂