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Comments 43451 to 43500:
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Tom Dayton at 11:28 AM on 17 July 2013CO2 effect is saturated
Stealth, I have replied to your comments about the quality of models on a more appropriate thread: the counterargument to "Models are Unreliable."
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Tom Dayton at 11:26 AM on 17 July 2013Models are unreliable
Stealth (on another thread) wrote "I would love to examine the source code of some GCMs to see if Dr. Freeman Dyson’s claim that GCMs are full of fudge factors is true. I suspect that it is true because software modelers always have to make assumptions and design trades in order to get software to run in a reasonable amount of time."
Stealth, Freeman Dyson has no idea what is in climate models, as he himself has publicly admitted. For some reason he is comfortable admitting he knows nothing about climatology but in the same conversation stating his admittedly baseless speculations as if he is absolutely confident they are facts.
Probably what Dyson meant by "fudge factors" were parameterizations, which are not merely fudge factors. RealClimate has short explanations of parameterizations in its FAQ on Climate Models Part II.
Regarding the overall quality of the software engineering aspects of models: No software is perfect (not even software for controlling spacecraft), but good software is good enough for the purposes it is put to. Determining whether software is sufficiently good is a process called verification and validation (V&V). Climate models do go through V&V. The type of V&V must be appropriate to the type of software and the contexts of its construction and use. The same is true of V&V of climate models, as Steve Easterbrook explained; Steve used to do V&V for NASA software.
But the real test of GCMs' adequacy is in their ability to predict, which is quite good at the time scales they are expected to predict well. The forcing and feedbacks interact to produce temperature changes that bounce up and down. Those changes in periods of less then 30 years are called "weather," but those short-term weather changes average out across periods of 30 years or more, so 30 years is approximately the definition of "climate." Weather is not climate, so predicting weather is not the same as predicting climate. Weather, especially in small geographic areas, is nearly impossible to predict more than a week in advance, but climate, especially for large geographic areas such as the entire globe, is and has been successfully predicted decades in advance--notably by Arrhenhuis in the 1890s, with more fine tuning in each generation of model, for example by Hansen in 1988, and with increasing accuracy with each improvement in the models. The accuracy is most evident in graphics if you properly position the observed temperature line at its mean trend at the start of the graph, as explained with the last three figures in a post by Tamino.
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KR at 11:23 AM on 17 July 2013CO2 effect is saturated
Stealth - "Can I get the source to any of the GCM models? I doubt that I can..."
From the first two pages of a Google search on "code for climate model":
- http://csdms.colorado.edu/wiki/Climate_models
- http://www.azimuthproject.org/azimuth/show/Climate+model
- http://www.giss.nasa.gov/tools/modelE/
- http://www.cesm.ucar.edu/models/ccsm4.0/
- http://data1.gfdl.noaa.gov/nomads/forms/deccen/
Not too difficult to find...
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JasonB at 11:06 AM on 17 July 2013CO2 effect is saturated
Stealth,
I don’t have time to look at them all, and they give widely different projections based on the spaghetti graphs I’ve seen, so I’d only like to see the one that is considered the best.
This demonstrates a fundamental misunderstanding of what climate models are doing.
Weather is chaotic. The timing of even signficant events like El Nino/La Nina cannot be predicted years into the future. In order to distingish between long term climate change, and the effects of internal variability, it is essential that repeated runs of the same climate model exhibit different realisations of that internal variability. This allows them to be averaged together so that the random variations cancel out leaving behind the systematic changes that will dominate in the longer term.
Even then, there is a risk that the forecasts of individual climate models inadvertently contain systematic biases that won't be cancelled out by this procedure due to the choices that were made in designing them and potentially even software bugs. So different models from completely different groups are also combined, to see what is common in their forecasts and what varies between them. Given their varied nature, if they all predict the same thing to within some tolerance, then we can have a certain amount of confidence that the true answer lies within that range; if they disagree about something, then our confidence is reduced.
Of course, since they are all embodying known physics to varying degrees, they will all contain systematic biases towards "reality, as we understand it" in that regard.
Anyway, far from being an indication of failure, those spaghetti graphs are an essential element of determining the reliability of the forecasts and trying to predict the range of possible outcomes.
Can I get the source to any of the GCM models? I doubt that I can, but it is worth a try.
Perhaps you should check a little bit harder before beginning to "doubt"?
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KR at 10:58 AM on 17 July 2013CO2 effect is saturated
Stealth - RealClimate has links to both climate data and a number of model codes here, including GCMs and others.
"...GCMs are full of fudge factors..."
Um, no. They are full of physics. There are parametric approximations of small-scale phenomena, and for limitations of sampling and scale - but those are anchored in physical measurements, they are not "fudge factors" or tuning knobs for giving a specific result. Temperature projections and climate sensitivity are outputs of the models, not inputs, and a great deal of the variation between individual model runs comes from differing initial conditions. That variation is in fact part of the results, indicating to some extent the range of potential weather we might see around climate trends. See scaddenp's link above for more discussion.
You do, I hope, realize that "fudge factor" claims are essentionally accusations of fraud aimed at the model authors? And unsupportable ones, to boot?
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Tom Dayton at 10:58 AM on 17 July 2013CO2 effect is saturated
Stealth, the fancy computer models merely fine tune the basic projections that have turned out to be pretty accurate, starting in the 1800s, and the early ones certainly did not involve computer code because computers had not been invented yet. You can try some of those simple models yourself by getting an introductory textbook such as David Archer's Global Warming: Understanding the Forecast, or by taking notes while watching his free online lectures from his class at the University of Chicago.
Tamino has illustrated a simple climate model you can run without a computer if you have a lot of time, or with a spreadsheet if you don't mind using a computer. He also has a followup that's only a bit more complicated.
There are a bunch of other climate models that are simple enough for learning and teaching. One list has been compiled by Steve Easterbrook.
Code for slightly more complex or narrow models also is freely available. RealClimate's "Data Sources" page has a handy but short list. Even the full-blown General Circulation Models (GCMs) have freely available code. RealClimate's Data Sources page also has a handy list of links to those codes. Steve Easterbrook has a three-year old list of GCMs with links to whatever info he could find about getting their codes. See also Tamino's Climate Data Links.
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JasonB at 10:51 AM on 17 July 20132013 SkS Weekly News Roundup #28B
This dropped in my Inbox this morning:
Huge iceberg breaks away from the Antarctic
Quote:
For the Western Antarctic ice shelf, an even faster flow of the Pine Island glacier would presumably have serious consequences. “The Western Antarctic land ice is on land which is deeper than sea level. Its “bed” tends towards the land. The danger therefore exists that these large ice masses will become unstable and will start to slide,” says Angelika Humbert.
If the entire West Antarctic ice shield were to flow into the Ocean, this would lead to a global rise in sea level of around 3.3 metres, inundating many coastal towns and cities.
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scaddenp at 10:22 AM on 17 July 2013CO2 effect is saturated
Source code is available for many of them. See here for GISS ModelE. Weather is chaotic so the same climate model will different wiggles for different initialisations. They dont pretend to be able to predict weather. 20-30 years are what climate is about. There is a very useful article on interpretation here.
Understanding the real differences between different modelling approache is what CMIP5 (and its predecessors) is about.
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JasonB at 10:20 AM on 17 July 2013Climate Change Denial now available as Kindle ebook
PG_Bill,
While it doesn't address your desire to boycott Amazon, note that Kindle readers are free and available for many platforms, including MacOS X, Windows, and Android, so at least you don't have to pay for that. See e.g. http://www.amazon.com/gp/kindle/pc/download.
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StealthAircraftSoftwareModeler at 10:13 AM on 17 July 2013CO2 effect is saturated
John Hartz @239: I would love to examine the source code of some GCMs to see if Dr. Freeman Dyson’s claim that GCMs are full of fudge factors is true. I suspect that it is true because software modelers always have to make assumptions and design trades in order to get software to run in a reasonable amount of time. Can I get the source to any of the GCM models? I doubt that I can, but it is worth a try. I know there are a dozen so models, and if source code is available, which would you recommend I look at? I don’t have time to look at them all, and they give widely different projections based on the spaghetti graphs I’ve seen, so I’d only like to see the one that is considered the best.
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JasonB at 10:02 AM on 17 July 2013Sea level rise is exaggerated
DSL,
What Earthling is saying is that because starvation is bad for you, obesity must be good. Or because drought is bad, flooding must be good. This seems like the appropriate place for that argument.
If he's worried about ice ages, perhaps he should ponder the selfishness of squandering what could have been a useful geoengineering resource to future generations faced with an imminent glaciation; carefully burning fossil fuels to enhance the greenhouse effect just enough to maintain temperatures in the face of declining northern-hemisphere insolation due to the Milankovich cycles may well be the most cost-effective method for them to do so, if those resources are still around at the time.
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Tom Curtis at 09:56 AM on 17 July 2013Nils-Axel Mörner is Wrong About Sea Level Rise
Klaus @80, the lighthouse is located on the southern coast of the island, just north of the barren patch above the word "niveau" in your third picture. In that picture, it is covered by the icon for a photo, but you can still see some of the white cement(?) around its base.
If the description of the location of the photo is accurate, then it is clear it was not taken from the beach on the north side of the island adjacent to the lighthouse. That is because the photo is sighted along the beach, which clearly recedes leaving an expanse of water along the line of sight to the isthmus. Similar considerations indicate the photo was not taken along the shore of the bay that you indicate.
Rahter than either of those two locations, I suggest the photo was taken on the west end of the long white beach directly below the word "Minicoy" in your second photo. Indeed, it was probably taken pretty much directly below the second "i" (or the following two letters) of that word. As you will notice, the line of that beach directly aligns with the isthmus, which is clearly visible in the background of the first photograph.
The white sand at that location shows that wave action tends to deposit sand there, and given its location relative to currents, will not typically remove sand. It is a relatively sheltered location, however, and the rate of deposition is likely to be slow. Therefore I do not agree with your explanation of the photo.
To me, it is far more likely that the vine covered area on the beach is just that area that is most commonly wave swept only as a result of storm surge. Sea level in that area can vary by around 200 centimeters based on changes in large scale wind patterns (Indian Ocean Dipole) and by another 200 centimeters based on tidal action, but storm surge can lift sea level by one or two meters. Given such a low beach it would be extraordinary if occasional cyclones did not sweep that beach, and in doing so sweep the vine covered area of the beach. Such occasional storm surges would more than adequately explain the coverage of that area of the beach by rapid growing vines, but not by slow growing trees.
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Tom Curtis at 09:26 AM on 17 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Old Mole @43, I believe Anderegg et al, 2010 is the more appropriate study for comparison purposes. They show that mean expertise of climate scientists unconvinced by the evidence of AGW (UC) as measured by lifetime peer reviewed publications is 60, about half of that of those convinced by the evidence (CE) at 119 publications. Michaels appears to fall just below the mean for those who are UC, with around 50 peer reviewed publications over his lifetime, although he has far more non-peer reviewed publications for Cato or Heartland. Restricted to publications from 2007 forward, my search only reveals three publications. If he has indeed published four over that period, and a similar level of inaccuracy applies to the whole search it is certainly possible that he has more than fifty lifetime publications, and may have as many as one hundred. For comparison, here is a graph of the number of publications by researchers analyzed by Anderegg. Michaels falls in the second smalles category:
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Glenn Tamblyn at 09:14 AM on 17 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
old sage
You talk about "Co-operative movements due to thermal oscillation means that lattice waves involving many nuclei, phonons if you will, in collision have sufficient energy to cause photon energy level transitions in the electron bands"
In essence you are talking about Atomic spectrocopy. The absorption and emission of energy by an atom that involves transitions in that atoms internal energy levels.
This is not the basis of GH gas absorption/emission!
With GH gases we are dealing with Molecular Spectroscopy. The essential mechanism is as follows:
- Differing atoms have differing electro-negativities, differing tendencies to hold their elctrons closely or not. Oxygen for example is strongly elctro-negative, Hydrogen less so.
- When combined into molecules this can result in charge separations across a molecule, with one side of the molecule appearing to be negatively charged and the other positively so.
- Since the bonds holding the atoms together are not rigid, the individual atoms within a molecule are always jiggling around.
- So for molecules with a charge separation, this continual movement can result in a continuous movement of electrical charges.
- And based on Maxwells Eqns, moving electrical charges can generate EM Radiation(radiation). And conversely EM Radiation can cause a change in the movement of an electric charge (absorption)
Think of a ball on a spring, bouncing around. If you wack that ball with a stick the ball may end up bouncing more fiercely. You have trtansferred energy to the ball/spring system that is now stored as kinetic/potential energy of the ball/spring system.
Molecular absorption/radiation is about changes in the kinetic and potential energy of vibration of atoms within a molecule, the energy being trasnported into and out of the molecule based on Maxwells Eqns, not changes to the internal energy levels within the atoms.
It is an inter-atomic phenomenon, not intra-atomic.
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Glenn Tamblyn at 08:56 AM on 17 July 2013CO2 effect is saturated
Stealth
A very important distinction needs to be made and clarified here. The models that are being referred that calculate the 5.35 ln(C/C0) result are not climate models! They are Radiative Transfer Codes; solutions to the equation of Radiative Transfer. As such what they do is, given a known state for a column of gas - temperature, pressure, humidity and composition profiles - they calculate the instantaneous radiative state at any point in that column. As such, the underlying maths is actually relatively simple. And they work from databases of very well established spectroscopic data. There are no assumptions or time based modelling or projections, they calculate a single snapshot.
A bit like engineering stress analysis programs, where they do the same simple calculations many times over for small cells to build up the composite picture. And their results are used in a wide range of applications, Climatology is only one of them. They are used in astronomy, military,, satellite communications modelling, a whole host of different domains. And their results have been extensively tested in the field and in the lab. -
Old Mole at 08:52 AM on 17 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
I have a couple of problems with this article, although I am by no means a fan of Pat Michaels.
"Yet during that time [2007 to July 2011], Michaels only published four peer-reviewed climate articles. In comparison, 97 percent of the most actively publishing climate researchers agree that "most" of recent warming is manmade, and 84 percent of climate scientists say the public should be told to be worried or "very worried" about climate change. Despite this, USA TODAY, The Washington Post, and CNN all hosted or quoted Patrick Michaels in 2012."
I have no data to go on (although John Cook may well have, having just done a paper ) but based on no more than the SkS policy of citing learned articles as (Whozitz, 2013) and not (Whozitz, 2013a, b, and c) that one peer-reviewed article per year would put him in at least the upper quartile of those publishing, not the lower quartile as this paragraph rhetorically implies. I would be much more interested in how he got the sort of nonsense he persists in spouting in interviews past peer review.
Yes, he does get 40% of his funding from the fossil fuel industry, and yes, the Cato Institute was the Charles Koch Foundation for the first two years of its existence. You justifiably heap scorn on his claim that scientists support AGW because of "funding" (not money ... I think there is a difference) because that is an extraordinary claim for which he provides no evidence. But where is your evidence that Pat Michaels would be saying anything different if he did not receive any money from the fossil fuel industry? While not directly stated, the imputation is of venality on his part, and while I can believe there are some people who would be willing to prostitute themselves into saying anything in their client's interest, most of them go into law rather than science. Corelation is not evidence of causation.
Today is the 68th anniversary of the first field test of the biggest science project in history, in Los Alamos, New Mexico. I wish you all the best of luck keeping politics out of your science project ,,, at least much more than those scientists had.
Best wishes,
Mole
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Philippe Chantreau at 08:13 AM on 17 July 2013Nils-Axel Mörner is Wrong About Sea Level Rise
Well, Klaus, by now, I think it's pretty obvious. You demonstrated what real skepticism is like.On one side, a photo with no context and an authoritative assertion that has no backing. On the other side, the same photo, with all the context and numeric data. Who is right is as clear as the waters around the Maldives on a good day...
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scaddenp at 07:41 AM on 17 July 2013CO2 effect is saturated
ps. After getting the full picture on humidity from the link indicated, I'd be interested in your assessment of tactics used by Climate4you to mislead.
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scaddenp at 07:32 AM on 17 July 2013CO2 effect is saturated
Stealth - you say. "That cannot be true, otherwise people would not be building models as a way to attempt to arrive at these values."
I think you are confusing different models here. I dont think anyone is doing much on work on refining the 5.35 value from Myhre. As pointed out, the uncertainities are low and matches observation.By comparison global GCMs are trying to model what will be climate response to this deltaF. These models do have significant uncertainities resulting in varying estimates for climate sensitivity from 2-4.5. Dont confuse the difficulties with modelling climate response with the modelling required for calculating the forcings. Different models.
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MA Rodger at 07:27 AM on 17 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
old sage @231.
Do you mean this Stephan's Law? So what is j* = 5.76040e-8 x 300^4? Of course it could be the answer is 56 wm^-2, but bless my quintessense, the abacus has run out of beads!!
And one question. Does it matter a ha'p'eth that the receptor is at 0ºK? Your calculation is the Earthly emissions, not net Earthly emissions. And I'm still very worried by the bridge!!!
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PG_Bill at 07:22 AM on 17 July 2013Climate Change Denial now available as Kindle ebook
Kindle is an Amazon product and Amazon have been getting a lot of stick here in the UK recently, firstly for managing to avoid paying any tax at all, then also for being anti-union and squeezing the competition. Many people (including me) are boycotting them, which of course includes not buying a Kindle.
But good luck with the print edition. -
Klaus Flemløse at 07:20 AM on 17 July 2013Nils-Axel Mörner is Wrong About Sea Level Rise
I have tried to investigate the photo from Minicoy Island from 2010 taken by Nils-Finn Munch Petersen – se post 56.
Figure 6 One of the locals of Minicoy, Ali Manikfan, showing how much the island has grown. What was once the beach is now located well above the wave-washing zone, is becoming overgrown (just as many beaches in the Maldives; Fig. 4; Mo¨rner et al., 2004; Mo¨rner, 2007a,b) and invaded by land-snails (photo: N.F. Munch-Petersen, 1992). Link.
This photo has been used as documentation that the water level in the Maldives is decreasing. The photo was taken at the north side of the south-western part of the island close to the light tower looking towards the isthmus.
Here is a picture of Minicoy Island:
Here is a picture of the isthmus:
In the bay protected by the isthmus on the inside of the atoll, it is expected in most cases that new land will be created. Prof Nils-Axel Mörner and Nils-Finn Munch Petersen have used this as the proof of the decreasing sea level around the Maldives.
Using Google Earth, it appears that there is erosion on large parts of the island and a buildup of sand in at least two places as a result of coastal protection programs.
It would be pleased if someone could check my argument.
From Colorado University, I studied the water level around Minicoy Island. This is shown in the following figure:
This figure shows that the water level has increased by about 3.2 mm per year during the years 1990-2013.
So we have a paradox as Prof. Nils-Axel Mörner and Nils-Finn Munch Petersen claim that the water level is decreasing whereas sea level based on satellite measurements show the opposite. Who is right?
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Zen at 07:04 AM on 17 July 20132013 SkS Weekly News Roundup #28A
Does anyone know if there is a chart showing the long term trend in extreme weather events and, if so, could you provide a link?. Thanks.
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PluviAL at 06:27 AM on 17 July 2013Global warming games - playing the man not the ball
I tried to go to SLDF to make a small contribution, but my virus scan tells me it is a dangerous site. Does anyone know what that is about?
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cormac at 06:17 AM on 17 July 2013They didn't change the name from 'global warming' to 'climate change'
The premise is wrong for a third reason. According to the OED, the term 'warming' means gentle heating, and nothing about temperature
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Phil at 06:15 AM on 17 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
Apologies to KR and Bob @219 @220, I should have explained in more detail, however Bob guessed my method correctly! it was really was intended as an "order of magnitude" calculation to suggest that old_sage's comments @216 were the result of a lack of sagacity on his part.
Since the conversation has moved on, I would add that there is, in fact no such thing as a ground state for a molecule, there are, of course, multiple. For a triatomic linear moeclue such as CO2 there are 2 degenerate rotational states, 4 vibrational ones (symmetric stretch, asymmetric stretch and double degenerate bend) as well as the electronic state. At STP CO2 molecules will be in many excited rotational states, several excited vibrational states - particularly the bend which is a lowest frequency, and almost exclusive in the ground electronic state. The black body radiation from Earth is absorbed and emitted by the CO2 bend since its frequency coincides with the radiation emitted by earth. This is in the Infra-red region of the EM spectrum and is what KR refers to as Thermal Radiation. old_sage's reference to excited electronic states is simply a strawman.
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Lou Grinzo at 06:10 AM on 17 July 2013They didn't change the name from 'global warming' to 'climate change'
Thank you for this posting. I don't know why, but it seems that there's been a big uptick lately in the number of claims that "we" changed terminology as some sort of ploy to fool people.
Given how quickly we're losing ice just about everywhere on the planet, I guess we were VERY persuasive...
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gws at 06:08 AM on 17 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
The distribution of energy levels in a gas is decribed by the Boltzmann distribution. For atmospheric temperatures, several vibrational states above the ground state are populated for CO2 and all other greenhouse gases. However, this would still not guarantee a greenhouse effect if our atmosphere were homogenous in terms of pressure and temperature, which it obviously is not.
Textbook knowledge in one field (e.g. solid state physics) does not mean one understands gas phase physics, or can directly apply one to the other. In this case, an understanding of both (infrared-) spectroscopy and radiative transfer are needed. As oldsage seems to display major misunderstandings of even some basics, I suggest to tone it down and start form the beginning. As he said: "Get your text book out." Will you do that too oldsage?
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Composer99 at 06:00 AM on 17 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
This is practically impossible with CO2 molecules. CO2 molecules at STP are in the ground state - where do they get the energy to radiate? Your claim that they do is purely and simply due to external stimulation. CO2 is simply an agent, a receptor if you like, for radiation generated elswhere it then will obviously participate in transitions as it seeks to return to its groundstate. You confuse scattering, which involves re-transmission of a proportion of incident energy with spontaneous emission - which again cannot happen.
What parts of CO2 absorbs longwave IR from the Earth surface (or from radiating molecules elsewhere in the atmosphere) and CO2 molecules receive thermal energy from collisions with other molecules in the atmosphere are you having trouble understanding? Certainly these seem to qualify as "external stimulation" allowing CO2 molecules the opportunity to "get the energy to radiate".
Seriously, absorption and emission of longwave IR by greenhouse gases is observed & measured (as per graphs & sources provided in comments responding to you). Insofar as there is any actual contradiction between your claim (as quoted in this comment) and what is observed, you are putting readers into the position of having to accept one of the following:
- Observed and measured phenomena, consistent with known radiative physics, are false.
- old sage's claims are false
I put it to you that the choice is obvious (and unfavourable to you).
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KR at 05:38 AM on 17 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
old sage - What I have been discussing is thermal radiation, observed in all matter at a temperature greater than absolute zero - where kinetic energies cause dipole oscillations and accelerated charges, and result in photon emission.
A significant percentage of CO2 at standard temperature and pressure is indeed above ground state, and radiating, as can be shown with IR spectroscopy. And that energy could come from incoming IR at CO2 absorption wavelengths or perhaps from a heated wire - spontaneous thermal emission, not scattering. The emission spectra is dependent on gas temperature, not on any incoming IR.
Again, your physics claims regarding thermal emission from gases are simply nonsense, contradicted by hundreds of years of both theory and observations.
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Composer99 at 05:38 AM on 17 July 2013CO2 effect is saturated
Stealth:
Appeals to personal qualifications and arguments from incredulity such as on display in #236 and #238 are not terribly convincing.
All this:
Being a software modeler myself (for 30+ years) dealing with RF energy through atmosphere, I understand that what is measured in the lab, what is model in software, and what the real world does are almost always very different. The real world is so noisy and chaotic that I have found models are almost useless in predicting what will really happen in the real world. I would be stunned if this is not also true for this forcing equation, and GCMs in general.
Trying to measure this value for the real world, on average, is probably impossible given that the atmosphere is so different moment to moment and place to place, and changes in long term trends may be hard to determine since we have so little empirical measurement data.
I admit it *might be* correct, but I cannot prove or disprove it, nor can anyone else. This isn’t meant as a criticism of experts in this field, only a realization of my experience that the atmosphere is impossible to model accurately. [Emphasis mine.]
Your assertion that this is basic physics and models match the real world simply cannot be true. I understand physics (I have a physics degree) and I build software models for living (I also have a computer science degree) so I think I am qualified to speak to models and physics.
The climate is not that simple – far from it – so my assertion of uncertainty is, I believe, completely accurate and true.
strikes me as practically equivalent to:
I know what I'm talking about, trust me & not the data.
I don't believe this is true, therefore it is not true.
although I am sure it was not your intent to communicate such sentiments.
(I have highlighted in the quotes from your comments the three words that are often the butt of jokes on medical blogs: "in my experience" or variants there of are sometimes called "the most dangerous words in medicine". I see no reason why this maxim should not generally be applicable to other scientific domains, particularly when the person asserting it is arguing against the weight of evidence, as you are.)
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KR at 05:17 AM on 17 July 2013CO2 effect is saturated
Stealth - Perhaps you should re-read just what you have quoted:
...net energy balance... This uncertainty is an order of magnitude larger than the changes to the net surface fluxes associated with increasing greenhouse gases in the atmosphere.
Since what we are discussing WRT Myhre 1998 are radiative transfer codes, and the change in forcings due to changes in atmospheric composition, we are indeed speaking of the 'net surface fluxes' which have far lower uncertainties. You seem to be conflating uncertainties in accounting for multiple energy flows into a total budget with uncertainties in computing atmospheric spectral response - applying an entire collection of uncertainties to a tiny portion of the puzzle.
If you wish to discuss the total energy budget, the sum of individual components (and their uncertainties) of the energy budget, there is an appropriate thread. However, the radiative transfer codes are well proven, giving results within under 1% of observations (Chen et al 2007) including dealing with compositional changes - arguing any significant uncertainties in that regard (as you have) is quite frankly unsupportable.
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old sage at 05:13 AM on 17 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
I've made the physics as clear as a pike staff. The reason a solid emits as a black body is because the coming together of nuclei in close proximity forces the outer electronic bands so close together that they form a continuum of energy levels. Co-operative movements due to thermal oscillation means that lattice waves involving many nuclei, phonons if you will, in collision have sufficient energy to cause photon energy level transitions in the electron bands. It all goes on at the boundary layer as i/r cannot penetrate a solid for more than a skin effect depth so i/r cannot emerge from anything other than the skin.
This is practically impossible with CO2 molecules. CO2 molecules at STP are in the ground state - where do they get the energy to radiate? Your claim that they do is purely and simply due to external stimulation. CO2 is simply an agent, a receptor if you like, for radiation generated elswhere it then will obviously participate in transitions as it seeks to return to its groundstate. You confuse scattering, which involves re-transmission of a proportion of incident energy with spontaneous emission - which again cannot happen. Get your text book out.
I could also explain to you how phonon waves at very low temperature cause electrons to attract each other in pairs over very large distances (compared with the atomic diameter) but if you don't understand the above, you certainly wont understand that!
MA Roger - I just assumed stefans law with T 300 radiating to a body at 0K. -
MA Rodger at 04:54 AM on 17 July 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
KK Tunk @192.
I think this dialogue would benefit from my restating of the question @188. If you feel that you have answered this question adequately @190 & @192 then do say (although I would be surprised if this were so).
I here introduce a graph below showing the data from Tung&Zhou2013 Figs 5A&B. It presents quite a few questions but I will kick off here by asking about the wobbles in the blue trace.
The blue trace is the 10-year rolling average of residuals from the MLR obtained by subtracting the QCO2(t) function (introduced in your first SkS post) from the data presented in Fig 5B, and obviously re-based for clarity's sake. According to Zhou &Tung 2013 which covers your MLR analysis more fully than T&Zh13 "The residual ... should only consist of climate noise if the MLR is successful..." This conforms to my understanding of it.
Yet the blue trace showing the residuals from the MLR analysis in Tung&Zhou2013 shows a lot more than "noise." There are distinct wobbles and these are not small wobbles being 43% that of the original HadCRUT4 wobbles (red trace). The residuals thus contain a very significant part of the HadCRUT4 signal which the MLR analysis has failed to attribute.A cynic would point to such wobbles within the residuals as being indicative of curve-fitting.
For myself, I am more charitable and rather see the problem being that these wobbles have gone unreported in Tung&Zhou2013. Indeed, a very similar trace can also be derived from Fig 1B Zhou&Tung2013 yet that paper says of the data in Fig 1B "The global-mean temperature adjusted this way shows mostly a monotonic trend with some scatter." This blue trace is definitely not "scatter."
(Note that the graph below features data derived from your Fig 5A&B in Tung&Zhou2013 as there are other feature beyond the blue trace that I see requiring explanation & which I hope we can address in later comments.)Could you thus explain why this wobble is present in the residuals and why its presence has remained unreported?
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John Hartz at 04:22 AM on 17 July 2013CO2 effect is saturated
@StealthAircraftSoftwareModeler:
Out of curiousity, which climate models have you analyzed in depth?
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StealthAircraftSoftwareModeler at 04:13 AM on 17 July 2013CO2 effect is saturated
KR @237 To be honest, I’m fairly stunned by your response and I am not sure how to address it. Just out of curiosity, what is your background?
You seem to be asserting that the alpha coefficient of 5.35 of the CO2 forcing function is both accurate and precise because it has been empirically measured. That cannot be true, otherwise people would not be building models as a way to attempt to arrive at these values. Correct? Why build a model when you can just measure it. Your assertion that this is basic physics and models match the real world simply cannot be true. I understand physics (I have a physics degree) and I build software models for living (I also have a computer science degree) so I think I am qualified to speak to models and physics.
The climate is not that simple – far from it – so my assertion of uncertainty is, I believe, completely accurate and true. As further evidence to “prove” that there is enormous uncertainty in the climate, just read the TOA energy balance paper Stevens et al that was referenced by Tom Curtis @ 226. This is great paper! It is peer reviewed. At the end it states: “The net energy balance is the sum of individual fluxes. The current uncertainty in this net surface energy balance is large, and amounts to approximately 17 Wm–2. This uncertainty is an order of magnitude larger than the changes to the net surface fluxes associated with increasing greenhouse gases in the atmosphere.”
Think about that – the uncertainty in the energy budget is ten times larger than the fluxes associated with GHGs. This is clearly proof that my assertions of uncertainty are completely warranted.
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KK Tung at 04:06 AM on 17 July 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
In reply to MA Rodger at post 191:As I said, I didn't quite understand your question and so it would help if you could ask it again if my reply in post 190 was not satisfactory. In that reply I was trying to address your corrected version---note that it did not address the incorrect references to Figure 2. It contains two parts, the first part was that you should not take the wobbles in Figure5AB as the original interannual variation in HadCRUT4. It is Figure 4A that should serve that purpose. The second part was the last two sentences, which explain what the residual should contain in practice. Ideally, the residual (after the anthropogenic response) should contain only climate noise, but in practice, especially in early decades of the data record, it could contain data inadequacies. Some of these data problems could also be amplified by the MLR procedure: Some of the timing of the occurrences of El Nino warming events in the HadCRUT4 data may not be consistent with the ENSO index we used a century ago. So the MLR may produce a negative spike, while the warming spike still remains. We could allow a lag in response that optimizes the removal of ENSO variations in the early decades, but the same lag then messes up the recent decades, which have better data.
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KR at 03:37 AM on 17 July 2013CO2 effect is saturated
Stealth - Regarding Myhre 1998:
"I doubt it is realistic or correct relative to what is really happening in the real world."
You would be wrong. Those model results have been proven out, empirically measured by the satellite observations, such as those discussed in the opening post (Harries et al 2001 in particular). Have you read the opening post of this thread?
Yes, the Myhre results are based on numeric models of radiative absorption/emission - using column estimates from three multiple latitudes, three different models to minimize bias and atmospheric variation. And they have been confirmed - the satellite spectra show the same outgoing radiation as predicted by those models. And therefore the modelling of slightly different atmospheric compositions is trustworthy. There is really no doubt about them, no significant uncertainties in direct forcing calculations.
If your model reproduces observations from basic physics, it's a good model. Your issues about uncertainties are unwarranted.
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DSL at 03:32 AM on 17 July 2013Sea level rise is exaggerated
Earthling, does that fact somehow make rapid sea level rise somehow benign?
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John Fisher at 03:16 AM on 17 July 2013They didn't change the name from 'global warming' to 'climate change'
Here is one such example provided by Anthony Watts:
"Global warming" suggests a steady linear increase in temperature, but since that isn't happening, proponents have shifted to the more universal term "climate change," which can be liberally applied to just about anything observable in the atmosphere.
Climate Change without Catastrophe: Interview with Anthony Watts, oilprice.com, 11 March, 2013
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rockytom at 02:33 AM on 17 July 2013Global warming games - playing the man not the ball
To Brett N, #5. Your comment is one of the best I have seen in a long time. Indeed, this site is one of the best, if not the best, to try to educate the deniers. The problem is that most of them don't read or understand the material discussed here. The impetus for John Cook and I in writing our textbook (Climate Change Science: A Modern Synthesis) was to make the climate science/global warming truth available to college students perhaps taking their first class in science at the introductory college level. All we can do is throw the facts and truth ih the direction of the deniers and hope that some of it sticks. John's work in climate change science communication is extremely importand as is that of Dana and others, Mann, Mandia, Abraham, Santor, McKibbon, and many other climate scientists (the 97%).
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Earthling at 02:33 AM on 17 July 2013Sea level rise is exaggerated
If sea level was falling, Earth would be in an ice age and that wouldn't be nice for any of us.
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StealthAircraftSoftwareModeler at 02:04 AM on 17 July 2013CO2 effect is saturated
KR @222. I went and read Myhre 1998 that produced the ΔF = 5.35*ln(C/C0) W/m2 estimate for CO2 forcing. The issue I have with this is that the alpha coefficient of 5.35 is derived from three different models, which assume that the models are accurate relative to the global atmosphere.
Being a software modeler myself (for 30+ years) dealing with RF energy through atmosphere, I understand that what is measured in the lab, what is model in software, and what the real world does are almost always very different. The real world is so noisy and chaotic that I have found models are almost useless in predicting what will really happen in the real world. I would be stunned if this is not also true for this forcing equation, and GCMs in general.
Trying to measure this value for the real world, on average, is probably impossible given that the atmosphere is so different moment to moment and place to place, and changes in long term trends may be hard to determine since we have so little empirical measurement data. So while this is the “best go-to reference” we have, I doubt it is realistic or correct relative to what is really happening in the real world. I admit it *might be* correct, but I cannot prove or disprove it, nor can anyone else. This isn’t meant as a criticism of experts in this field, only a realization of my experience that the atmosphere is impossible to model accurately.
Tom Curtis @226: I think you made a minor math error. If the average global temperature is 15C, or 288K, then 0.5% of this is 1.44K. I love the energy balance diagram by Stevens et al 2012. I went and read the paper and I found it quite interesting. Since Kevin Trenberth has generated a topic on the energy budget (http://www.skepticalscience.com/news.php?n=865), I am going to take my questions and comments about the energy budget over there.
Scaddenp @227. Just because warmer air can hold more water vapor, doesn’t mean it will. Charts I have seen (http://www.climate4you.com/GreenhouseGasses.htm) of humidity for the atmosphere over time has been about the same at low levels, but at higher altitudes relative humidity has been decreasing. If these charts are correct, this seems to suggest that water vapor has not increased as the atmosphere has warmed over this time period (65 years).
Moderator Response:[TD] For your comment on water vapor, please read the counterargument to "Humidity is Falling," and if you disagree with the peer-reviewed evidence presented there, please comment there. Regarding water vapor in the stratosphere, see "What is the role of stratospheric water vapor in global warming?" Anyone who responds to Stealth's comment here about water vapor, please, please do so on those other threads, not here. Everybody must help to keep the conversations on the appropriate threads. Thank you.
[TD] Thank you for recognizing that another post is the right place to talk about energy budget!
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KR at 23:59 PM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
old sage - You make several absurd claims:
"CO2 does not radiate as a black body, it merely scatters and absorbs - that is until you get it up to several thousand degrees, and I don't know how many, but it doesn't occur where you assert it does!"[ ] ...Sorry, CO2 in gaseous form cannot convert kinetic to photon energy except under the rare circumstances I suggest..."
I cannot emphasize enough how wrong those statements are. CO2 (and CH4, and ozone, and CFCs) absorb (not scatter) and emit over a broad IR spectra, with photon emission coming from electron orbital relaxation, and electron excitation being easily converted between orbital and vibrational modes, with a corresponding ability to interchange kinetic and electronic energy. Ionized plasmas are simply not required.
You might find it useful to read up on Kirchhoff's law of thermal radiation, which states that "for an arbitrary body emitting and absorbing thermal radiation in thermodynamic equilibrium, the emissivity is equal to the absorptivity", meaning that the emission spectra at radiative equilibrium is identical to the absorption spectra.
Your assertions regarding gaseous IR emission, to be blunt, are total nonsense contradicted by physics and observations. If as you state you have a background in thin film superconductors, you should know better. Until and unless you decide to discuss physics, rather than Just So Stories, your posts are not worth anyones time.
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Composer99 at 23:45 PM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
old sage claims:
CO2 does not radiate as a black body, it merely scatters and absorbs - that is until you get it up to several thousand degrees, and I don't know how many
Just so I'm clear here, old sage, which of the two below are you suggesting:
- CO2 does not radiate electromagnetic energy as a perfect blackbody, while still radiating electromagnetic energy.
- CO2 does not radiate electromagnetic energy at all until reaching very high temperatures.
I'm assuming, based on the clause after the dash, that you are claiming #2.
Even based on less-reliable "common sense" inference this claim is plainly false, to say nothing of empirical measurements of the outgoing E/M emission spectrum of the Earth by satellite, which are consistent with emissions of longwave IR at temperatures well below "several thousand degrees".
As an approximation I would describe the Earth's emission spectrum as a composite of of blackbody-like curves between 220-320 K, consistent with the evidence presented by Tom (and others) and inconsistent with the bizarre claim you are attempting to advance.
(Incidentally, it seems to me that, for the purposes of E/M emission into space, you have got the wrong boundary.)
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MA Rodger at 23:42 PM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
old sage.
I think I am beginning to discern the bridge more clearly here. You say @223 that "I calculate that earth surface emits 56 w/m2 and what doesn't get straight out goes into gas kinetic energy." I would be interested to see how you calculate the 56 w/m2.
And with this, you also assert @227 that "CO2 in gaseous form cannot convert kinetic to photon energy except under the rare circumstances." You appear to be proposing that gases do not emit radiation. It would be useful to know where do you get this idea from. -
MA Rodger at 23:15 PM on 16 July 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
KK Tung.
Your reply @190 describes itself as being a reply to me @188. I have to say that I am not entirely clear that it is.
I can see that it is a reply to me @170. But as I point out in my first paragraph @188, my comment @170 mistook Fig 2b in your 1st SkS post as being equivalent to Fig 5b of T&Zh13. And it is this Fig 2b that strangely still features the HadCRUT4 signal. Thus such a reply as yours @190 is commenting on a mistaken thesis - not a productive use of words.
My first paragraph @188 was solely by way of an apology for my mistaking that Fig 2b for Fig 5b (although the strangness of Fig 2b does remain unexplained and this may be an issue for yourself).But enough of that initial paragraph @188.
You will surely note that @188 I present more than one paragraph. You will note that the second, third and fourth paragraph are the ones that lead up to my question which is the point at issue @188. Any response to my comment @188 would hopefully address these paragraphs and that question.
Now, it is not impossible that the final two sentences of your comment @190 could be construed as some sort of response to these final paragraphs. Yet they are so indirect and carry such implication that I find it hard to see them as a reply. If they are your reply, could you confirm as such. If they are not, a reply would be good.
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old sage at 23:05 PM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
I have just looked back at the reference you made TC refuting a previous post of mine about co2 radiating - and quite rude it was too. (CO2 obviously re-radiates a proportion of the energy by which it gets excited but your back-radiation - which will increase with concentration of CO2 - simply means more comes back becasue the number of scattering centres is denser.) Sorry, CO2 in gaseous form cannot convert kinetic to photon energy except under the rare circumstances I suggest, it would just defy the most basic conservation of energy rules. Dense concentrations in solids have that capacity by a process you seem to understand.
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old sage at 22:45 PM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
jmorpuss - very good reference that, that is where I am coming from because from a global viewpoint - and any radiating surface - it is the boundary conditions which determine the performance and earths boundary is a shimmering mass of charged particles. Various lens-like changes occur with height. (I should point out my research - a long time ago - was in thin film superconductors of the second kind where magnetic field breaks down into quantised vortices) I imagine such movements high up generating long wave radiation correlated with atmospheric energy levels (hopefully).
TC you repeat what I said in 1 but ignore the consequences. CO2 does not radiate as a black body, it merely scatters and absorbs - that is until you get it up to several thousand degrees, and I don't know how many, but it doesn't occur where you assert it does!
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Tom Curtis at 21:48 PM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
Old Sage @223:
1) Solids, like all elements and molecules, absorb and emit radiation at discrete wavelengths corresponding with the discrete energy levels of electron shells, molecular bonds and rotational and vibrational patterns. In solids there are so many elements, so closely packed that the number of such discrete wavelengths is very large so that the radiation will often closely approximate to that of a black body. Nevertheless, the discrete wavelengths of radiation and absorption are there, and are no different in principle in behaviour than that of gases.
2) I have already shown this to be wrong by observational evidence here.
3) Like all substances, CO2 radiates at specific frequencies. The intensity with which it radiates at those frequencies is a function of temperature, based on the laws of black body radiation.
4) At least you got this correct, if nothing else. Unfortunately everything that follows is wrong.
You write:
"If co2 does not stop radiation completely in a clear sky from escaping, it is having little effect, even if it does it accounts for what, 1 % of the spectrum."
This illustrates the absurdity of your position. To actually claim that if CO2 stops 99% or IR radiation, it will have no effect because it is not 100% (ie, completely) is not only wrong, it is nonsensical.
You further write:
"On the quantum front, I suspect solar radiance is worked out by multiplying the normal figure by cross-section."
You are again wrong. The mean solar irradiance is calculated as the Total Solar Irradiance divided by the ratio between the surface area the Earth, and of a disc with the radius of the Earth perpendicular to the Sun's rays (which ratio happens to be 4) - then multiplied by one minus the bond albedo of the Earth. The bond albedo is the reflectance averaged over all angles. Therefore, the standard formula actually incorporates the information you say is ignored, and which you say is not measured.
You write:
"I calculate that earth surface emits 56 w/m2"
Again, you are simply wrong. Below are radiative fluxes at the surface as measured over Lake Ontario. The upwelling surface flux is given as a negative value (dashed line) because it is in the opposite direction to the net short wave radiation (red line, consisting of incoming sunlight minus reflected sunlight) and the back radiation (short dashed line). Note that the surface flux never drops below 200 W/m^2 (as measured), nearly four times your estimated maximum value. It would be much larger in tropical areas, which constitute 50% of the Earth's surface.
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