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Ken in Oz at 10:14 AM on 16 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Barry @18 -
I'm guessing that the focus on surface air temperatures is because 1), it is only recently that ocean heat content indicea have been collated, 2) impact of global warming (for humans anyway) will be experienced mostly at the surface.
This is true, however most of the discussion about statiscally significant warming and the false climate denier conclusion that warming has slowed or stopped for 17years that has followed our comments looks kind of pointless in light of the clear and measurable global warming - 4 Hiroshima bombs per second worth - that has been occurring during this period of "no significant warming". Even if temperature records for oceans don't go back as far as surface air temperatures (because existing meteorological records was where much initial effort was spent looking for climate change signal) they are adequate now to measure a fundamental change in the climate system's energy balance - which SAT's do not.
Of course this is just one way to frame the discussion - alternatives include focus on the known natural oscillations, cycles and underlying climate processes. In order for the deniers and obstructors to maximise the spin value (spun falsewards) it is necessary for them to falsely imply that if SAT's don't rise consistently year to year, decade to decade then something besides GHG's are responsible - and other things besides are indeed responsible for most of any short term up or down but the deniers and obstructors assiduously avoid examining them closely. Flattening of SAT's presents a window of opportunity to mislead the public and the public's political representatives. As I said before, when el Nino hits, "global" temperatures hit new highs, they will rediscover selected natural phenomena like ENSO that, when applied to the current period, reveal the lack of foundation for their 'warming has stopped, climate scientists are wrong' arguments.
Foster and Rahmstorf showed clearly that when you take the known natural influences out of the SAT records much of the internal variation disappears and a clearer look at the underlying trend is revealled. ie there is no 17 years of no warming. It's entirely an artifact of an artificial argument, intended to obfuscate the seriousness of a global problem of unparalleled extent.
But they overlay a strong clear warming trend with ups and downs. Well, ups and levelling offs because of that underlying warming. That's worth pointing out; if there was no underlying global warming those would indeed be ups and downs - 'statistically significant' periods of SAT's going unmistakeably down. Short lived periods, of course, because the bulk of those variations are due to oscillations like ENSO.
If global heat content were THE measure of change to our climate system all these arguments about statistically significant trends over 'x' number of years become more clearly what they are - time wasting distractions.
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Glenn Tamblyn at 10:06 AM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
old sage @216
It isn't just CO2, its all the GH gases. And the other non-GH molecules in the atmosphere are bumping into them all the time. In fact the kinetic energy of those collisions is the source of the energy that the GH molecules are radiating.
All the IR radiation in the atmosphere originates from the GH molecules, the non-GH molecules, O2 and N2 particularly cannot radiate in the IR wavelengths required. The radiation from the GH molecules comes from the fact that the individual atoms in the molecule are joined by flexible bonds between the atoms. So the atoms in the molecule are always vibrating, jiggling around like balls on springs. Essentially kinetic energy is stored in the bonds between the atoms. Some of this energy can then be released as a photon of IR radiation, resulting in the GH molecule vibrating a little less. However, the continuous collisions between molecules can quickly 're-energize' the GH molecule so that it is able to radiate again.
When you think of the energy being radiated from the atmosphere as coming from the combined energy of all the molecules in the atmosphere it may not sound so strange. It is just that in order to be radiated it has to be channelled through the GH molecules to 'get out'. -
scaddenp at 09:54 AM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
Old Sage - your inability to understand something does not make wrong. You have been pointed to the text book stuff. Why dont you actually start there? I should also point out that the spectroscopy tests of theory have been repeated numerous times and the Radiative Transfer Equations predict the results of experiments with exquisite accuracy. If your conception of physics is at odds with experimental observations, then its time to revise your conceptions of physics. Pick up a text book.
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Tom Curtis at 09:47 AM on 16 July 2013Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
Old Sage @7, this initial comment is just to clear up some (frankly silly) arguments so as to not distract from the main substance.
1) The radiator analogy: A radiator of a car in motion will not boil if it has sufficient coolant and the water pump is working. It is only if the car is stationary that disconnecting the radiator fan is sufficient to cause the radiator to boil. Further, pointing out that radiators do not loose most of their heat by radiation is irrelevant. "Radiator" remains their name, and the analogy merely points out that if you maintain a constant energy input, but decrease the energy output, the system will warm. A significant number of AGW deniers deny that basic fact.
2) The CO2 concentration in the atmosphere is measured in parts per million by volume (ppmv), not parts per million by mass. The atmospheric concentration is now 400 ppmv, so it is 4 moles of CO2 for every 9996 moles of other gases; or if you like 1 molecule of CO2 for every 2499 molecules of other gases.
3a) Your quotation of 2.9 W/m^2 forcing ignores the forcing from aerosols, which is negative. Therefore it overstates the total forcing by nearly a factor of two. Further, it is the forcing, which is the difference in top of atmosphere (TOA) radiative imbalance for a given change of radiative conditions prior to any responses to that change, including increases in temperature. Feedbacks and increases in temperature will further alter the TOA energy imbalance, with positive feedbacks increasing it, and negative feedbacks and increases in temperature reducing it. As it happens, the increase in temperature since 1750 (the reference date for forcings) has reduced the TOA energy imbalance to 0.6 W/m^2.
3b) The energy increase caused by the greenhouse effect is distributed among all Earth's surface components. That includes the upper few meters of soil, the melting of snow and ice, the increase of temperature of the ocean and the increase in temperature of the atmosphere. It even includes any increase of storage of chemical energy resulting from the CO2 fertilization effect, although that amount is (comparitavely) too small to consider. Of these components, the atmosphere absorbs around 2% (1.4% according to Church et al, 2011) of the heat, while the ocean absorbs over 90%.
If you want to pursue this line of argument, this link leads to an appropriate thread.
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sylas at 09:24 AM on 16 July 2013It's waste heat
A comment on convection and transfer of heat...
Where there is a hot spot or heat source on the surface (from waste heat, for example) convection is a crucial way that excess heat is carried away and up into the atmosphere. As I understand it, convection is extremely effective; and it transfers heat much faster than radiation in the atmosphere -- as long as there is an energy imbalance to drive the convection.
Convection, however, is capped; it cannot carry heat away out into space. So it will tend to bring the atmosphere into a state of convective equilibrium. This equilibrium is called the "lapse rate". This is the temperature profile of the atmosphere where there is no transfer of heat energy as a "packet" of air moves up or down. The temperature change of the atmosphere at different altitudes matches the temperature change from expansion or compression with the pressure change (and condensation, in the case of a moist atmosphere). An "unstable" atmosphere is one where convection will restore the equilibrium, and this cannot last for long before convection restores the conventional lapse rate. This is caused by heat at the surface or low altitude.
You can also get cases where air at higher altitude is warmer than you would expect from the lapse rate; but this case is called “stable”, because convection doesn’t move hot air downwards. This condition of the atmosphere is broken up usually by winds and horizontal circulations, or else by loss of heat from radiation of the hot air – a much slower process than convection.
This doesn’t support Old Sage’s claims; the actual energy flows from convection are pretty small by comparison with radiation. Convection is fast, but as with any spontaneous thermal process, it works to remove the conditions which drive it. Radiation works more slowly, but this energy flow is not capped at the top of the atmosphere, so there’s a continuous ongoing flow of radiation out into space.
The lapse rate in the atmosphere – the fall in temperature with altitude – is a crucial part of how the greenhouse effect works. The capacity of the atmosphere to absorb and emit IR radiation means that a much of the Earth’s emissions to space comes from emissions high in the atmosphere; where it is cooler than the surface. In order to shed the heat Earth absorbs from the Sun, temperatures overall must be that much hotter to get a balancing emission of energy back to space.
Summary sentence: the efficiency and speed of convection maintains the atmosphere close to conditions of a convective equilibrium – in which the major energy flows by far are from radiation.
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KR at 09:21 AM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
Bob Loblaw - Ah, that would certainly explain the difference in numbers; my misunderstanding then.
That back-of-the-envelope calculation would require specifying the transient climate sensitivity, and/or the mass directly involved. Timing is everything, after all...
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Bob Loblaw at 09:17 AM on 16 July 2013Understanding the long-term carbon-cycle: weathering of rocks - a vitally important carbon-sink
Patrick 027:
Ever wondered where table salt comes from? Perhaps mined from sodium chloride precipitated from the sea? How about potash (potassium salts). which are mined extensively for use as fertilizer?
As they say, if you aren't part of the solution, you're part of the precipitate...
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Bob Loblaw at 09:11 AM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
Actually, KR, Phil was talking about the change per year, not the total change. If the 2.9W/m2 is held steady, it would take a little over 100 years to cause a total change of 1 degree.
I'm guess that Phil just took a mean water depth and heat capacity to get his number. One catch is that the entire ocean depth is not evenly mixed. Thus, the heat tends to warm the upper layers faster, so a surface temperature response will see a greater increase than the 0.082K per year in the early years, and the deep ocean takes a while before it shows heating.
Phil could explain the assumptions behind his back-of-the-envelope calculation a in bit more detail.
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Patrick 027 at 08:54 AM on 16 July 2013Understanding the long-term carbon-cycle: weathering of rocks - a vitally important carbon-sink
(haven't commented here in a while; wow, this looks different)...
K, Na - don't ordinarily form carbonates - so what happens to them to remove them from the ocean? When more CO2 is making the ocean more acidic, would more Na and K ions act the same way on pH as dissolving CaCO3?
How much more more CaCO3 would be in solution if precipitation were all abiogenic?
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Utahn at 08:25 AM on 16 July 2013Global warming games - playing the man not the ball
Ok, it only makes sense if you have an inaccurate view of that analogy...Whoops
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Utahn at 08:22 AM on 16 July 2013Global warming games - playing the man not the ball
Thanks for fighting. Incidentally, when I first saw this post I was thinking, "man" = global energy imbalance, and "ball" = surface temperature, and I thought that's a great analogy I haven't seen before!
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Artful Dodger at 08:19 AM on 16 July 2013Global warming games - playing the man not the ball
"It has clowns, hockey sticks, and witches"
And don't forget: T*R*O*L*L*S !
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glhoffman at 07:53 AM on 16 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
With regard to post no. 34, there are more fundamental problems with current models in making projections because they are largely unverifiable.
Moderator Response:[PW] Discussion of 'models are wrong' are veering a bit off-topic for this thread: further discussion should be posted here.
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KK Tung at 07:35 AM on 16 July 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
In reply to MA Rodger at post 188: I had trouble understanding your original posts---that was the reason I didn't respond to them then. I may still not be understanding it; so please correct me if I misinterpret your points. You are looking at the interannual variation of the original data in HadCRUT4. This was shown in Figure 4A, not Figure 5A of Tung and Zhou (2013), PNAS. Figure 5A is the result of one round of MLR, after removal of ENSO, vol and solar influences. Figure 5B is the adjusted data, and it contains everything that remains after removal of ENSO, sol and solar, plus AMO influence. It should contain anthropogenic response plus climate noise ideally. In reality it also contains errors in observation and the interpolation that was used to come up with the global mean, especially in the early decades in the 20th century; the 50 years prior to that was especially bad, datawise. You can see that after 1970s, the variations about a linear trend do look smaller and like random noise.
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KR at 07:22 AM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
Phil - Actually, a 2.9 W/m2 top of atmosphere forcing should directly raise temperatures by about 0.877 C, not including feedbacks.
Calculation: start with the Stefan-Boltzmann relationship of
or Power = emissivity * SB constant * Area * Temperature4
The Stefan-Boltzmann constant is 5.670373*10-8 Wm-2K-4, surface temperature in Kelvin averages 15 C + 273.15 = 288.15 K, and for area we can assume one square meter.
Starting effective Earth emissivity = Power / (SB constant * T4) = 240 W/m2 /(SB * 1 * 288.154) = 0.6139
With 2.9 W/m2 missing, effective emissivity = 237.1 W/m2 /(SB * 1 * 288.154) = 0.60652
To radiate 240 watts with a lower effective emissivity, and remove the energy imbalance, a higher temperature is required. T = (240 W/m2 / (SB * 0.60652)) -4 = 289.03 K = 15.877 C. That's a direct, pre-feedback temperature difference of 0.877 C.
Moderator Response:[DB] updated image link per request.
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Brett N at 07:13 AM on 16 July 2013Global warming games - playing the man not the ball
Twenty years ago I thought the science was complete enough to begin a plan of action to slow the advance of climate change. Sadly, I was naive enough to think our politicians would do the right thing and start to implement the changes required. Silly me, while I went off and lived my life a drama of truly epic proportions was being played out. Heroes and villains, dark forces pulling the strings of puppets ensnared in a web of greed, subtext and innuendo abounding. Shakespeare be dammed, scientists rock!My thanks go out to all of you who have advanced our fight for survival. More than once, I have descended into the twisted rabbit hole of a denier site. Such a pretty argument, so simple, so easy to be sucked in, only to find myself lost in a maze of half truths and sound bites. Yes, more than once, a lifeline thrown by the posters on this site have saved me. Your selfless dedication to the truth, and boundless patience in educating even the slow ones such as myself, should be recognized by all, as truly heroic. -
Phil at 06:56 AM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
The 2.9 Wm-2 surplus doesn't heat the atmosphere; it heats the entire planet. My back-of-envelope calculation (literally !) suggests that should result in an annual temperature rise of 0.0082K
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supak at 06:52 AM on 16 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Tom Curtis @ 17
While some of what you said went over my head, I appreciate your input and will definitely try to hunt down some of the information you offered.
jdixon1980 @ 36
"so that I wouldn't end up having a financial stake in "rooting" for the human race to continue to drive itself into devastation."
That's funny, and what my wife often laments about my propensity to want to gamble on the future of the human race. I don't have these qualms because I don't have to root for a bad outcome. It's already going to happen.
My guess is that even if he has millions in the bank, he has no plans to pay out on any such bet, so I'm probably wasting my time. But I am keeping what he's saying and plan to make a blog post out of it at some point. I'm just looking to get some input from you guys so I don't look like a fool.
See, while I understand a lot of this stuff, I'm really just a gambler who is always looking for a sure thing. I cannot think of anything much more sure than the fact that we are going to see significant warming of surface temps in the next 25 years.
I do, however, like the comment from Ken in Oz @ 16 that going by surface temps alone is a fool's errand. We shoud be sure to always mention that the vast majority of the warming has gone to the oceans. If only there were some accurate measure of ocean warmth I could get Micheals to agree on, then I'd include that as a seperate bet.
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michael sweet at 06:43 AM on 16 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Ray,
If the best you can come up with for the IPCC exaggerating AGW is an obvious typographical error I take that to mean you agree that the IPCC has not exaggerated AGW at all. A non-skeptic scientist found that typo and the IPCC has publicly acknowledged that they copied an error from another publication.
I dare say that all of the regular posters here agree with Gavin on the "science is settled" statement. Your post here implies that at Skeptical Science we claim the science is settled. Perhaps you need to write your posts more carefully so that you are not misunderstood.
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Kevin C at 06:03 AM on 16 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Ray: You comments are based on a simple but common misunderstanting of statistical significance. We have been meaning to do an article on this, but there never seems to be time. See Misuse of Statistics for an overview.
A statistical significance test on a trend can only disprove the null hypothesis, it cannot prove it. Therefore the fact that the trend on some arbitrary short period can never falsify the hypothesis of continuing warming. That's a simple statistical fallacy.
The confusion arises from the fact that the test is not symmetric. It can falsify the hypothesis of 'no trend', but it cannot falsify the hypothesis of 'continuing trend'. For that you need to change the test.
That may seem counterintuitive, but it's really very simple. If a trend is not statistically significant, it's telling you one of two things. Either
- There is no trend, or
- You don't have enough data
But it doesn't tell you which, so you have no more information than when you started. On the other hand if the trend is statistically significant, then you know that both
- You have enough data, and
- There is a trend
(subject to the given confidence intervals).
Thus, whenever you hear someone quoting the lack of statistical significance of a trend as evidence for a hypothesis, you can immediately conclude that they don't know what they are talking about.
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KR at 04:34 AM on 16 July 2013Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
old sage - Yes, GHGs share energy back and forth with the surrounding atmosphere.
The electron relaxation time for a CO2 molecule is on the order of 10-6 seconds before radiating a photon, while at sea level pressures each gas molecule will collide ~109 times per second - meaning that a CO2 molecule will average roughly 1000 collisions before it can radiate. Therefore the GHG molecules and the surrounding atmosphere are at the same temperature.
The thing is, at thermal equilibrium the absorption spectra of an object (including a volume of gas) is equal to the emission spectra - and as much energy leaves as enters. Note that this doesn't mean the same molecules radiate as absorb, just that statistically as much energy is radiated as absorbed by radiatively active molecules in that volume. And those that radiate do so becase they have the energy to do so, because they are warm enough.
Again, you are presenting Arguments from Incredulity, in contrast to facts, to measurements. Your personal inability to get your head around those facts does not invalidate them.
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old sage at 04:07 AM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
TD - high time the calibration of spectrographs was investigated if measured.
I cannot get my head round 3 kgs of CO2 absorbing and emitting 350 watts of energy surrounded by 3000 times as many other molecules - do they all agree not to bump into them. I also cannot get my head round the alleged 2.9 w/m2 surplus from GG's. That's equivalent to raising earth's atmosphere 10 degrees p.a. - I think we would notice that!
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old sage at 03:58 AM on 16 July 2013Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
I have been directed to this thread but could not even start to question it, there are too many lacunae in the reasoning starting from the car engine analogy. The engine boils even if the pump keeps pumping because the heat is transported by the pump and has to be dissipated by conduction/convection through the vanes of the 'radiator' - where radiation is irrelevant, just stop the fan to find out. Radiator is a misnomer for a domestic device for conduction and convection of heat - physicists should know that.
I cannot get my head round 3 kgs of CO2 molecules accepting and re-emitting 300 watts of radiant energy in the presence of three thousand more numerous molecules of N2 O2 H2O etc - do they all agree not to collide with them so as not to convert the energy to kinetic?
I cannot get my head round the 2.9 w/m2 said to be the surplus greenhouse heating - that equates to raising the atmosheric weight of air through10 degrees p.a. - I think we would have noticed it somehow.It's time someone addressed their energies to the way spectrographs are calibrated.
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jdixon1980 at 03:20 AM on 16 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Supak @14, 15: Any bet that I made, I would want to bet on different outcomes for different emissions scenarios, so that I wouldn't end up having a financial stake in "rooting" for the human race to continue to drive itself into devastation. But I'm not a climate expert - maybe 25-year predictions don't depend much on which emissions scenario happens during those 25 years, in which case I applaud your denier tax.
On the other hand, is Michaels making enough of these bets that he is liable to go bankrupt and leave you unable to collect?
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JasonB at 02:36 AM on 16 July 2013Empirical evidence that humans are causing global warming
Earthling,
That would have to be a record-breaking transition from "It's not us" to "It's good". Well done. Now you just need to familiarise yourself with the consequences of AGW before deciding that it's a good thing.
Thanks to all who replied, I'll consider the possibility that humans have caused somewhere around 74 to 122% of warming and compare it to the IPCC WG1AR5:
"It is extremely likely that human activities have caused more than half of the observed increase in global average surface temperature since the 1950s."
"The greenhouse gas contribution to the warming from 1951–2010 is in the range between 0.6 and 1.4°C. This is very likely greater than the total observed warming of approximately 0.6°C over the same period. {10.3.1}"
I'm not sure what you mean by "compare", do you think your statement is inconsistent with the two quoted? The first is talking about all human activities, the second is specifically talking about greenhouse gasses and echos the comment I made earlier as well as reflecting the most recent scientific literature (which is what the IPCC is actually doing, after all), pointed out already by Daniel Bailey.
"If it doesn’t get warmer over the next years, then it likely will be blamed on the increased share of anthropogenic cooling."
Note that this statement is not from the IPCC WG1AR5. Although it was indented differently, I found the fact it was included in quote marks immediately afterwards and in the same font to be misleading. It's actually a translation of a comment on a blog post!
It also displays a desire not to understand how the system actually works and even criticises genuine scientific attempts to do so when the results don't fit the simplistic strawman that had been constructed.
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Bob Loblaw at 01:35 AM on 16 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Ray:
No, I was not under the impression that you did the statistical analysis. I was hoping that you understood the analysis well enough to know what it really meant. That hope is currently dwindling.
I am still at an impass, with insufficent observations to distinguish between two hypotheses. Those were listed in my last paragraph of the comment above, but I will reword them here, perhaps a little more directly (or bluntly):
1) are you unfamiliar with the proper way of determining a null hypothesis and incoporating that into the "expected value" of a statistical significance test (e.g., t-test)? If this is the case, then are you willing to learn about it before you make any further uninformed comments about significance testing?
2) If you are familiar with how to appropriately choose an "expected value", then why are you making statements that are not supported by the statistical tests that other have done? - e.g., the incorrect idea that a non-significant difference from zero means that the trend is zero? If you do know the meaning of such tests, and are deliberately twisting them into something that they do not actually mean, then that raises questions as to your sincerity.
There may be another explanation that I am not considering, so feel free to provide alternatives. For now, if I had to bet, I'd go with option 1, given that you do not seem to know what null hypotheses others have used in their trend calculations.
To try to keep at least a bit of this on-topic, Pat Michaels seems to often fit into option 2: I think he knows better, but he realizes that many casual readers/observers do not. Consequently, he twists the science into something it is not, makes grandiose statements that lead people to where he wants them to be, and to hell with what the evidence really says. I would not buy a used car from him.
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barry1487 at 01:32 AM on 16 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Despite all this however I do wonder why, in the face of ever increasing CO2 levels, the trends for all the major global temperature data sets are at best showing increases that are not statistically significant and more recently are, apparently, flat
A warming climate does not preclude weather events, and at short time periods the 'noise' can obscure the signal.
There is no statistically significant warming for the last 3 years. Do you think that represents a trend in climate?
You need a premise with which to begin assessing climatic changes rather than the variance within the system. One of the first things to ask is, "how long is enough determine global climate change?" Obviously a few days or months or a handful of years isn't enough. So how long do you need before the short-term effects roughly balance and a climate signal emerges?
Robert Grumbine attempted a mathematical estimate some time ago.
http://moregrumbinescience.blogspot.com.au/2009/01/results-on-deciding-trends.html
The following is worth reading, too.
http://tamino.wordpress.com/2012/07/06/how-long/
(In the 7 to 8 years I've been browsing the climate debates, not once have I come across a 'skeptic' doing analyses like these. It is obvious why that is so)
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rockytom at 01:07 AM on 16 July 2013Climate Change Denial now available as Kindle ebook
"Climate Change Science: A Modern Synthesis" may also be available in your local library. If not, you can request that they order it. I think that Springer offers a special discount to libraries.
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barry1487 at 00:52 AM on 16 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Himalayan glaciers vanishing by 2035
Not an exaggeration, an error, which IPCC acknowledged when it was pointed out. AR4 has a few other errors in it.
You're better off choosing the first or second assessment reports (FAR 1990, SAR 1995), Ray, because projections from the TAR (2001) or AR4 (2007) generally can't be tested owing to the short time span since.
If you want to focus on surface data, 20 years is a fairly good minimum time period, and a bit more for satellite data - if atmospheric temperatures are the metric you prefer.
Skeptical Science has a handy tool for that - here. The trend results come with uncertainty estimates. You can get an idea of how much data is needed to achieve statistical significance by changing the time period length. You might want to test claims you've read about by plugging in the time periods, and seeing if the trends are greater than the uncertainty. It's a useful bookmark for the climate debates.
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John Hartz at 00:47 AM on 16 July 2013It's waste heat
Old Sage:
The Science of Doom is a "go to" website for anyone seeking to better understand the mathmetics of climate science. The site is devoted to evaluating and explaining climate science in a very structured manner. It has a 13-part series about Atmsophereic Radiation which you should carefully study.
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Tom Dayton at 00:41 AM on 16 July 2013It's waste heat
Old Sage, I have replied to your comment on an appropriate thread. If you want to continue this conversation, do so over there, not here.
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Tom Dayton at 00:39 AM on 16 July 2013Trenberth on Tracking Earth’s energy: A key to climate variability and change
Old Sage (from an inappropriate thread), you are ignoring what KR pointed out: The numbers in that energy budget are based on actual measurements by hundreds of scientists, refined over many years. You can read about their methods by following the links to the original peer-reviewed papers. That budget does not violate any laws of physics. Really, it does not. It's not even hard to understand. But first you must actually try to understand it. It is clear from all of your comments on Skeptical Science so far that you are not really reading, let alone really trying to understand, anything. You would fail an Introductory Climatology class simply by refusing to read and try to understand.
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old sage at 00:22 AM on 16 July 2013It's waste heat
Very interesting chart that KR, it rewrites the laws of physics replacing that of conservation of energy with conservation of radiation and as for the kinetic theory of gases, forget it. Hardly a joule from conduction and not an erg from the radiative shell surrounding earth.
Hey ho.Moderator Response:[TD] Put your comments about the energy budget somewhere more appropriate, such as the post by Trenberth. Put your comments about the basics of the greenhouse gas mechanism somewhere more appropriate such as the post Tom Curtis pointed you to. In all cases, you really need to read the original posts before commenting.
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tmac57 at 00:08 AM on 16 July 2013Global warming games - playing the man not the ball
I don't know that the story contains "witches",but it most definately has witch hunts as an element.
My contribution will be sent to PEER today.Thanks John Abraham.
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Ray at 00:02 AM on 16 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Michael Sweet Himalayan glaciers vanishing by 2035. I'm fairly that's not an "absurd claim" Sorry but I don't know if there is a link to "The science is settled" at SkepticalScience but here's one to Real Climate in a piece written by Gavin Schmidt. http://www.realclimate.org/index.php/archives/2009/12/unsettled-science I thought this comment of his was very relevant: "The reason why no scientist has said this is because they know full well that knowledge about science is not binary – science isn’t either settled or not settled". Too true
Bob Loblaw you appear to be under the impression that I did the statistical analyses of the temperature data. I didn't You'd have to ask those that did to find out what their null hypothesis was. Hope that is explanation enough but I don't recall seeing it specifically stated
Moderator Response:[TD] The Himalayan glaciers error is covered here.
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John Hartz at 00:01 AM on 16 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
@Glenn Tamblyn, Tom Curtis, Bob Loblaw:
It would be extremely beneficial to all of our readers if you guys were to meld your responses about statitiscal significance into a blog post article.
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DSL at 23:53 PM on 15 July 2013Global warming games - playing the man not the ball
And you can add this to the lovely correspondence the cro-mags have defecated toward climate scientists.
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DSL at 23:47 PM on 15 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
And finally, Ray, if you come up with a period of statistically insignificant warming, or even a period with a negative trend, so what? What does it mean? Is it "aha! gotcha!"?
David Rose of the Daily Mail thinks that it means that "global warming has stopped," and he's quite willing to use his power to spread that message far and wide. Do you think a sixteen year statistically insignificant warming trend in global average surface temp means that global warming has stopped? If so, what does a sixteen year trend of .286C per decade mean (1992-2007)? Do you think it's good methodology to use the surface trend to claim a theory has been demolished, and to do so without performing a component analysis, and without accounting for ocean heat content and the energy used in (accelerating) global ice mass loss.
Aha! Gotcha! Oh ho! Uh huh!
No. The theory of anthropogenic global warming is not based on the global average surface temp trend. The theory did not start with "hey. it's warming. i wonder what's causing it." It started with "hey, per Tyndall, CO2 is a greenhouse gas. I wonder what would happen if humans increased atmospheric CO2."
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DSL at 23:30 PM on 15 July 2013Empirical evidence that humans are causing global warming
Earthling, I've responded to part of your sentiment here.
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DSL at 23:29 PM on 15 July 2013It's not bad
Earthling: "It would seem that we humans have probably done ourselves a favour by acting to avoid a decline in global temperature."
What, by missing the next glacial period 1500 to 5000 years from now? Sure, the LIA sucked, but so did the PETM and end-Permian. The PETM event involved a change in global average temp of 5C over 12,000 years. That's what extreme looks like. We're doing about 40x the rate of PETM warming. In what shape will we be when the time comes for us to miss the next glacial period? When is the best time to develop sustainable energy and greenhouse management technology? When the world is rich in energy resources and relatively stable politically, economically, and socially? Or when cheap energy is diminishing, food prices are rising, climate is persistently unstable, and many more people are on the move trying to find a better place to live? I think the idea is that we reach the next "missed" glacial period without having gone through the school of hard knocks and instead having shown that we're mature enough to drive the family car.
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kar at 22:58 PM on 15 July 2013Climate Change and the Nature of Science: The Carbon “Tipping Point” is Coming
A general problem far beyond this article, is that too often the horizon of problems into the future is set to be like 87 years or may be couple of hundred years (until 2100 or a couple of centuries more).
Even quite a lot of science article fail to mention what David Archer told us in the The Long Thaw - it will last more than 100,000 years to reach back to preindustrial state of CO2 content in the air ... -
kar at 22:40 PM on 15 July 2013Climate Change and the Nature of Science: The Carbon “Tipping Point” is Coming
Is it not a error in the start of the 6th section? Where it should be to and not from?
There is written:
"... that there are 3.1 billion tons of extra carbon being added from the atmosphere ..."
Should been:
"... that there are 3.1 billion tons of extra carbon being added to the atmosphere ..."
... and it could be also be added in the end of the sentence: ... every year.
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michael sweet at 20:47 PM on 15 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Ray,
I am still waiting for you to provide examples of the IPCC exaggerating the AGW problem. You suggested at 2 above the IPCC exaggerates the AGW problem. SInce you referenced WUWT above I presume you have not seen any posts there that document the IPCC exaggerates the AGW problem. If you provide no examples that would indicate that your suggestion of exaggeration was incorrect.
Please provide a link to a Skeptical Science thread that claims "the science is settled". There is much to learn about AGW. On the other hand, even the skeptics now admit that the temperature is increasing. The greenhouse effect and the contribution of CO2 is also no longer debated by scientists. If you want to suggest that we have to convince WUWT you will have to be more specific about what you claim is not settled. What exactly are you claiming is not settled? Please provide specific examples.
It is easy to make absurd claims if you are not required to back them up with specific examples.
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Paul D at 20:27 PM on 15 July 2013Global warming games - playing the man not the ball
The fact is, climate science undermines the established economics and politics of the 'left vs right' meme for the last 100 years or so.
So it was always going to be a rough ride.Galileo experienced the same problem trying to get the political (religious) establishment to listen.
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MA Rodger at 20:23 PM on 15 July 2013It's waste heat
old sage.
Your argued position here appears to rest on the method used to measure themal conductivity in fluids as described in your physics text book. Radation and convection effects are something such a method would require to reduce to insignificance because if not the measurement method would need amending to account for them.
Thus when you say radiation is only 5% the effect of conduction, that simply demonstrates a well designed method (although 5% due to radiation is actually pretty rubbish, to be honest).
But you are taking this 5% figure and asserting it to be some universal ratio of the relative importance of conduction and radiation. Such a use is nonsensical.
I would suggest you read the rest of that physics text book. This will allow you to make some very basic calculations for the size of radiative energy fluxes through the Earth's atmosphere and you will quickly discover that the 5% figure is entirely inappropriate.
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Cornelius Breadbasket at 19:22 PM on 15 July 2013Global warming games - playing the man not the ball
There are many scientists on this site, and in particular menioned in this article that I'd like to nominate for the John Maddox Prize. I'm hoping that readers here may also make nominations.
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Earthling at 16:44 PM on 15 July 2013Empirical evidence that humans are causing global warming
JasonB, "(i.e. the temperature would have actually declined without human GHG emissions)."
It would seem that we humans have probably done ourselves a favour by acting to avoid a decline in global temperature.
The LIA, wasn't a time I would have enjoyed living in, for me, the 40s were bad enough.
Thanks to all who replied, I'll consider the possibility that humans have caused somewhere around 74 to 122% of warming and compare it to the IPCC WG1AR5:
"It is extremely likely that human activities have caused more than half of the observed increase in global average surface temperature since the 1950s.""The greenhouse gas contribution to the warming from 1951–2010 is in the range between 0.6 and 1.4°C. This is very likely greater than the total observed warming of approximately 0.6°C over the same period. {10.3.1}""If it doesn’t get warmer over the next years, then it likely will be blamed on the increased share of anthropogenic cooling.".
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Bob Loblaw at 14:56 PM on 15 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Ray makes two statements (in two different comments):
"If the rise is not statistically significant is it really a rise?"
"In my own field of science which is biochemistry, Student's t-test is routinely used as a measure of significance."
The unstated question is: not statistically significant compared to what? If you are as familiar with a Student's t test as you claim, then you will remember that an important step in the calculations is where you determine "observed - expected". In the case of a temperature trend, "observed" is the slope from the regression, and "expected" is the value from your null hypothesis. But what is your null hypothesis?
- if you want to see if the slope is non-zero, then your null hypotheis is zero and your expected value is zero. This is very common.
- if you want to see if the past warming trend has "stalled", or "stopped", etc., then your expected value is not zero, as your null hypotheis is that the trend has not changed. To use zero as the expected value is wrong - you should use the previous trend value as your expected value. This mistake is also very common.
For the case where a calculated trend is neither significantly different from zero, nor significantly different from the previous trend, then the data that you have is insufficient to distiguish between those two null hypotheses. Which is where Glenn and Tom's comments about short time periods become relevant.
If you are unaware that a t-test can use an expected value other than zero, then you've got some learning to do. If you are aware that an expected value can be non-zero, then you've got some explaining to do.
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Ray at 14:36 PM on 15 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
The link is http://en.wordpress.com/tag/werner-brozek/. In the article the author comments on the slope of the lines. As I stated I'm a biochemist not a climate scientist and I acknowledge that comments such as those by Tom Curtis and others are from those with more understanding of the science than I have. That said, the scientically trained layman can see that "the science is settled mantra" may be premature from some the findings reported.
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Tom Curtis at 14:33 PM on 15 July 2013Patrick Michaels: Cato's Climate Expert Has History Of Getting It Wrong
Ray @23, you now show evidence of some statistical sophistication. Given that, I wonder how you can justify parsing:
"The hypothesis of no warming has not been excluded"
as:
"There has been no warming".
To my mind the later is a positive claim, in effect stating that the hypothesis of warming has been excluded by the data. And that is, of course false. In science, no hypothesis gets prefferential treatment. Not even the nul hypothesis, and failing to disprove the null hypothesis is not the same as proving the null hypothesis, no matter how many times deniers pretend to the contrary.
In this case, however, the null hypothesis is only disconfirmed if you cherry pick your start points to limit the data available; and if you exclude other known relevant data (such as ENSO states). I wonder how you would mark a student who, having tested a hypothesis and excluded the null, dropped half of the data and redid the test, then reported only the data used in the second test along with a confident claim that the failure of that data to exclude the null hypothesis showed that the hypothesis being tested was false (ie, "There has been no warming.")
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