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Tom Curtis at 13:59 PM on 14 October 20142013 SkS Weekly News Roundup #27B
michael sweet @10, there is some truth in claims that Gasland overstates the case against fracking. For instance, of three people apparently mentioned as having methane contaminated water as a result of fracking in Weld County, Colorado, two, including Mike Markham (featured in the scene showing water from the tap being lit by a ligher), were found to have methane of biogenic origin. However, the third case the well of Aimee Ellsworth was found to contain"... a mixture of biogenic and thermogenic methane that was in part attributable to oil and
gas development...". Given the standard McAleer and (apparently) Louis use for accusations of dishonesty, the failure to mention that case by either demonstrates them both to be liars. Perhaps Louis was merely ignorant.Including the example of Sherry Vargsson (22 minutes in) featured in the video I posted above, that gives two clear examples of groundwater contamination with methane as a result of fracking operations. Further, it is quite possible that the two biogenic cases had no or limited methane in their gas prior to fracking operations. Presumably they at least claimed that to Fox (certainly Fox claims so, another apparently "not relevant" Louis neglects to mention).
Speaking of missing important details, in Fracknation McAleer says to Fox, "You have said yourself, people have lit their water long before fracking started." (2:41) To that, Fox replied, "Yes, but it is not relevant."
LuisC presents this case by stating:
"At least some of the residents in the town straight up agreed that gas was coming out of faucets well before the company had any operations in the area. This was not mentioned in Gasland, which left the viewer with the impression that the flammable gas was being released because of fracking. When asked about this very issue by McAleer in a seminar, Fox replied that ''it's true, but it's no relevant''. I would be interested to know how he maintains that it's ''not relevant'', when indeed many people have been left with the impression that gas coming out of faucets is something new under the sun and that fracking is to blame."
Check the wording. Fox was not asked about "this very issue". The example Fox mentions and agrees to comes from New York, not Colorado. McAleer had mentioned a 1976 report for Colorado but Fox does not indicate he has read it. Nor are we told why Fox thinks reports of earlier instances are not relevant. Although clearly from the video he has more to say, he is cut of once McAleer has his sound bite, and McAleer continues with his rhetorical voice over.
One thing I have noticed in watching excerpts of McAleer's video is a blanket refusal to question industry claims. Worse, when reporting on a successful campaign to prevent fracking in the Delaware basin, he reports it as a case of remote bureacrats "depriving farmers of their livelihood". Now I'll grant the decision deprived some farmer of a potential revenue stream, but McAleer is claiming that the decision will prevent the farmers from making a living - that in fact farming on their farms will not earn them a livelihood.
The bias is overwhelming. But then, what did we expect?
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Glenn Tamblyn at 13:26 PM on 14 October 2014CO2 effect is saturated
Bob
Interesting reference. Unfortunately the graphs cover different parts of the spectrum.
Fig 1 is for CO2, smack bang in the center of its absorption curve. And it shows just how big a factor line-broadening is.
Also it answers the important question of absorption path length, at least near the peak. The upper graph in Fig 1 is essentially sea level pressure. Right at the peak at 667.5 cm-1 there is only about 3% transmission - 97% absorption - after 1 meters. After even 10 meters that would be 0.0310 or 0.000000000000059049%
Even just at 667.0cm-1 there is about 83% transmission - 17% absorption - after 1 meters. So about 15.5% transmitted after 10 meters and it takes around 170 meters to match the absorption at the peak.
Fig 2 actually cuts off the peak absorption region for CO2 on the far right just as it has dropped to maximum absorption.
Fig 3 is centered near the peak of the Ozone absorption, with only a modest role for CO2 there.
Referring to the opening equation - 7.1 - the Spectral Intensity S of CO2 is one of the key factors here. The other factor, the function f() covers line broadening etc and is where a lot of the complexities are.
This is a graph of the value of S for CO2 over much of its key absorption band, taken from the HITRAN database using the website spectralcalc.com
Notice the vertical scale is logarithmic. There is a roughly 6 orders of magnitude difference between the height of the peaks at the center and the peaks at the edges. Those are the wings.
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Bob Loblaw at 11:23 AM on 14 October 2014CO2 effect is saturated
KR:
I did find a set of lecture notes at this link. Figure 7.3 seems to suggest that even at the peak absorption bands you see a few percent of IR reaching 13km altitude from the surface, but that graph is at higher wave numbers (lower wavelengths) than the most active IR absoprtion bands. Figure 7.2 is a much lower resolution, but does show the greatly-increased absorption by CO2 as you move out into the longer wavelengths.
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Bob Loblaw at 11:08 AM on 14 October 2014CO2 effect is saturated
KR:
You prompted me to dig out my copy of Pierrehumbert's Principles of Planetary Climate, but unfortunately his graphs of CO2 absorption coefficients are in units of m2/kg and there is no easy conversion to simple units of length. Too much math for an evening at home at the end of a long weekend.
...but, to read the reference you linked to, what I find there is a series of calculations ultimately based on density, which appear to estimate how much of the volume of air is occupied by CO2. This is used to calculate the "mean free path length of quantum/waves in the atmosphere before colliding with a molecule of carbon dioxide".
What I do not see there is any discussion of how often a "collision" [and I use that term loosely] actually leads to absorption. Nor do I see any indication that the calculation takes wavelength into acount, which is a huge factor in absorption. (CO2 only absorbs at selected wavelengths.)
I suspect, but have not done the math to confirm, that if you repeated the calculation for nitrogen (much more prevalent in the atmosphere) that you'd get an even shorter "mean free path length" for N2 - but we know that N2 does not absorb IR strongly. He does seem to think that "molecules of water vapor and solid particles" in the atmosphere are much more important, basically because photons will run into them first.
In other words, I think the 33m that he comes up with has absolutely nothing to do with how far a typical IR photon travels in the atmosphere before being absorbed by CO2. We do know that photons outside the CO2 absorption wavelengths will go a lot further than ones at the appropriate CO2 wavelengths, and his calculations do not identify that.
Oddly, even though he calculates a "mean free path length" much shorter than I would expect for the distance before IR absorption, he also uses this to conclude that CO2 is not a greenhouse gas. This conclusion appears to be due to the speed with which an IR photon can escape the atmosphere.
Overall, I think his math is just a bunch of technobabble that amounts to an argument that trace gases can't be radiatively active. It's an odd flavour of CO2 is just a trace gas.
Rob:
Not just a Professor, but a "Scientific Research Director". Unfortunately, if I try a Google search for "Biology Cabinet Division Mexico" - his stated location. I only seem to find links to other copies of his paper at the usual denial web sites. He's a legend in his own mind.
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michael sweet at 11:02 AM on 14 October 20142013 SkS Weekly News Roundup #27B
Louis,
From your post I understand that you have seen an industry reply to a documentary that was nominated for an Oscar as best documentary. You claim "scientific studies" have shown something but you provide only a citation to the industry propaganda. Perhaps you can support your claims with some data besides industry propaganda?
You have been provided undisputable evidence about earthquakes. There is widespread data concerning pollution of drinking water by fracking. Your tale of cancer is different from the one on Wikkipedia, perhaps you need to cite your source so we can see if it holds water.
It seems to me that Fox has better to do than to reply to this propaganda. No-one at SkS has felt it interesting to write an article about it. It seems off topic for this site to me.
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jja at 08:02 AM on 14 October 2014Dinner with global warming contrarians, disaster for dessert
Recent research has suggested that the lower climate sensitivity estimates preferred by Curry, Lewis, and other contrarians are likely incorrect because they fail to account for different efficiencies of different climate influences, and underestimate the amount of global warming in the oceans.
Can we have a frank discussion about this paper? I have run a few comparisons using Nuccitelli et. al. 2013 data set and have found that this reanalysis of southern hemisphere ocean heat radically changes things. On the high end, it shows a 30% increase in Top of Atmosphere energy imbalance. http://oi59.tinypic.com/2ykax6a.jpg (green line is bets fit slope of Nuccitelli curve with projections going forward).
This reanalysis shows that the current TOA is closer to .9 Wm^-2. It also indicates that, while the northern hemisphere values appear to be correct, this likely indicates that NH Aerosols are significantly understated as well, possibly by a factor of 2.
If the energy accumulation raties continue along the best-fit curve then we are going to be experiencing catastrophic heat accumulation rates in only a few decades.
http://oi62.tinypic.com/289fyuw.jpg
This not only makes lower ECS and TCR values unlikely (impossible) but also shifts the most likely value up by 20% or more (3.6C vs 3) and the Fat tail is even fatter with a potential ECS of 8C.
Am I reading this wrong?Moderator Response:[PS] Fixed link
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Rob Honeycutt at 08:00 AM on 14 October 2014CO2 effect is saturated
Bob... Thanks. That makes sense to me. I figured that Jonathan had essentially tripped himself up with his insistance on using the fog metaphor. He makes that error very early in the video and essentially continues off in that direction for the rest of the 20+ minutes.
KR... Yup. He's a CO2 as a GHG denier, and a college professor as well.
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LuisC at 07:50 AM on 14 October 20142013 SkS Weekly News Roundup #27B
Hi Michael Sweet and Tom Curtis,
thank you for your responses. There are a few issues to sort out here:
My source for doubting the claims made in ''Gasland'' is the documentary ''Fracknation'', by Phelim McAleer. While we may rightfully doubt whether someone who has in the past been funded by the energy industry will present us with all the relevant facts, there were enough counter-claims made in the documentary to make me think that Gasland fell severely below the mark in terms of presenting all the relevant facts as well. For example:
- the people in the town focused upon in Gasland seem to mainly be in favour of the gas company's operations when asked by McAleer (they were also furious at their town being reduced to something of a caricature in the media, and many were against the construction of a water pipeline to bring clean water to the town, given that they themselves thought it was already clean). At least some of the residents in the town straight up agreed that gas was coming out of faucets well before the company had any operations in the area. This was not mentioned in Gasland, which left the viewer with the impression that the flammable gas was being released because of fracking. When asked about this very issue by McAleer in a seminar, Fox replied that ''it's true, but it's no relevant''. I would be interested to know how he maintains that it's ''not relevant'', when indeed many people have been left with the impression that gas coming out of faucets is something new under the sun and that fracking is to blame.
- the couple, mentioned in both documentaries, who filed a lawsuit against the gas company rejected the EPA's own results for water contamination when the results showed that there was no significant contamination from fracking. The EPA released footage of the couple being presented with the results; they replied by flying off the handle, denouncing the EPA as peddlers of ''bullshit'' and hurling accusations of ''what happened to you guys?'', and (in the case of the wife) essentially threatening McAleer with physical violence. I'm not accusing the couple of deliberate lying, but there seems to be, at the very least, a problem of circular reasoning here: the couple will only accept results that conform to their opinion. I mention their emotional response only to emphasize that science doesn't work by emotion or circular reasoning, but through the testing of assumptions. In the case of contamination of water in the town, the assumptions were clearly unfounded, which undercuts a key claim relies upon by Fox.
- many farmers are in favour of fracking, due to the revenue it brings, which in turn allows them to stay in business. It also makes sense to me that farmers, whose entire livelihoods and in many cases heritage is based upon using the land (and indeed, maintaining the health of the land) would never grant permission to a company to drill under their land if there was a serious threat of contamination of ground water. This suggests to me that fracking is not significantly more dangerous than other methods of extracting natural gas when it comes to water contamination, even if, like those other methods, it still carries risks.
- Fox claimed in Gasland that a region (or city) of the US had experienced greatly elevated levels of cancer from fracking. This turned out to be flatly incorrect and contradicted by a scientific study which found no evidence of this.
Now, it's possible that Phelim McAleer, for his part, had extrapolated too much from his focus upon the particular claims made in Gasland and had sidelined cases in other localities where fracking has been shown to be a danger, but this doesn't mean that the particular claims made in Gasland about the aforementioned localities and people have been scientifically verified. This is why I asked if Fox has issued a rebuttal against his critics, since Fox was basing his claims about fracking largely upon the cases he looked at in his documentary. As for the claim that this would be ''a waste of time'': isn't this very website about rebutting the claims of climate change deniers? Would you say that this website is a waste of time? Personally, I find it to be an invaluable source of information, which, if nothing else, provides me with the scientific community's view on the matter (just as ''TalkOrigins'' provides me with the scientific community's view on evolution against creationist claims).
Furthermore, many people who are genuinely interested in getting to the truth of the matter would want Fox to tackle the claims made in Fracknation. Even if ''new data'', as you say, has ''proven him correct'', this might apply to cases other than those he looked at. If fracking poses a danger in Oklahoma, for example, this doesn't mean that it poses a danger in the places Fox focused on. Thus, a blanket condemnation of fracking seems inappropriate based upon the cases Fox focused on. Finally, if certain claims are incorrect and are disseminated by those who care about the environment, this only ends up assisting those who don't care about the environment, for the latter can then latch on to these cases to ''prove'' that ''environmentalists don't care about the truth''. We must always, without reservation, seek to uphold the highest standards of truth when making our claims. Anything less becomes a disservice to our side and a gift to the other side.
There's another, more general, point to be made. Fracking, being a method of extracting natural gas, might be dangerous but in a more round-about way than cancer, earthquakes and contamination. To the extent that fracking faciliates more extraction and the driving down of gas prices, it is of course facilating humanity's ''addiction'' to fossil fuels, and in this sense is dangerous. But this is different to the separate question of whether fracking is inherently more dangerous than other methods of natural gas extraction due to the risks it poses in terms of cancer and earthquakes. Even if it didn't do these things, it would still present a long-term threat to the environment through its system-wide impact on energy use. This is an issue that tends to be overlooked by focusing either too much on its particular dangers, or of trying to deny them. Not that these dangers should be overlooked, of course. I'm just wary of the possibility that these dangers might inadvertently serve as a distraction from a larger systemic issue. But anyway, I'm just putting my thoughts out here. -
CO2 effect is saturated
Ach, horrible reference in my last message - turns out the author is a denier of CO2 as a GHG, my apologies. He doesn't seem to understand what happens when there is a change in effective radiating altitude. Still, the path length discussion is reasonable.
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CO2 effect is saturated
Bob Loblaw - Sorry if I wasn't specific enough, that's absorption at major GHG frequencies. There are plenty of atmospheric windows and lower sidebars of partial transmission, but for strongly absorbing frequencies CO2 has a mean sea level path length of ~33 meters or so.
IR gas analyzers, on the other hand, are generally less than a meter in any dimension :)
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Bob Loblaw at 06:41 AM on 14 October 2014CO2 effect is saturated
KR @298:
Where do you get the "absorption of IR is effectively saturated near the ground at sea-level pressures, with the average absorption path length being quite short (in the order of meters)" statement from? Even at wavelengths were CO2 absorbs, my impression is that it can travel significant distances. IR spectromoetry is a common method of measuring atmospheric CO2 concentrations, and commerical sensors can handle up to 3000ppm, IIRC, suggesting that at 300-400ppm we're far short of "saturation".
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Bob Loblaw at 06:30 AM on 14 October 2014CO2 effect is saturated
Oh, what a complex subject radiation transfer is...
First, I have not watched Jonathan's video. At 30 minutes long, a video is a very slow way of gaining an understanding. I'd rather read.
There is a similarity between atmospheric transfer of IR radiation and headlights in fog, but there are also significant differences.
First of all, photons travel in fairly straight lines. (We'll ignore refraction for now.) Photons passing through a medium (e.g. the atmosphere) can basically do three things:
- it can be transmitted - pass directly through, unaffected, continuing in the same direction,
- be absorbed, at which point the photon no longer exists and the energy is transformed into something else,
- be scattered, at which point we still have a photon of the same wavelength, but it is travelling in a different direction.
IR doesn't get scattered in the atmosphere - the wavelengths and molecular and particle sizes don't match up. It either is transmitted or absorbed. The ratio is expressed by Beer's Law, which is logarithmic. Over a given distance, if 10% is absorbed and 90% transmitted, then the next equal distance will absorb another 10% - but of the 90% that was transmitted - i.e., 0.1*0.9 = 9% of the original, not 10% of the original.
The transmitted amount after 2 units is 0.9*0.9 or 81%. Over N units of atmosphere, the transmitted amount passing through is 0.9^N - so after 10 units of "10% per unit" we get 35% transmission, not 0% (10*10%). At 50 units, we're now at 0.5% transmission.
Is the transmission "saturated" at 50 units? Some might say yes, because if we increase the absorption per unit to 15% (thus, transmission per unit = 85%, or 0.85), then at 50 units we see 0.03% transmission (0.85^50), but so what? We only had 0.5% before anyway... is there really any difference between 0.5% and 0.03%? If we look at what is going on at 10 units, however, 0.85^10 = 0.20 or 20%. At 10 units, we've dropped from 34% transmission to 20%. The concept of "saturation" is now dependent on where we are. What seemed "saturated" at 50 units doesn't quite look that way at 10 units.
In the case of transmission of IR from the surface to the top of the atmosphere, even if (at some wavelength where CO2 absorbs) there is next to no radiation reaching the top of atmosphere directly, adding CO2 can still affect how much reaches a lower altitude directly - i.e., the average distance travelled before absorption will decrease. Although almost nothing reaches 100km directly, the amount reaching 10 km may now only reach 9km, or 8km, or 7km...
Once absorbed, energy will be re-radiated as IR again, but the re-radiation happens in all directions. Half of that will be moving down, not up, and to get it out to space, it will have to be re-radiated several times. The more CO2, the more times it will be absorbed and re-radiated, and the more times that happens the less efficient it is and the warmer the surface must be. This is the basic greenhouse effect.
Now, back to lights in fog. Most of the light passing through fog will be either transmitted or scattered - not much is absorbed. The amount transmitted directly still follows Beer's Law, though. A lot of the scattered light still travels forward, but we'll be seeing it from other angles - not directly. We can "see" the lights as long as the amount of light transmitted directly is still greater than the amout we see that is being scattered by the fog. Once too much of the direct light is scattered, the headlights get "lost in the fog".
When we can't see the lights at 100m, we might say "the fog is saturated", but at 50m we can still see the lights. (Tom makes this point above.) If the fog gets heavier, the person at 100m can't tell the difference, but the person at 50m does - until she can't see the lights. Another person at 25m still does, though, and when the fog gets heavier and you can't see the lights at 25m, you still can at 12m, etc., etc. etc. Each observer is looking at exactly the same lights and atmosphere, so if only some of the observers are saying "it's saturated" and other aren't, then the concept of "saturation" is not actually a universal property of either the lights or the fog - it is something that tells us more about the observer's position than anything else. This is not a useful concept for radiation transfer.
Now, to compare IR to lights in fog, the big difference is absorption vs. scattering. But just as absorbed IR is re-radiated both up and down, the lights are scattered both forward and backwards. The observer standing 50m from the car will see the lights fade into the fog as it gets heavier, and the driver of the car will get more of the light shining back in their face as the fog gets heavier. What the driver sees in back-scatter is similar to IR "back-radiation". Even though the observer at 100m says "the fog is saturated", the driver can tell the fog is getting heavier. Just as the case with increasing atmospheric CO2: although the observer at the top of the atmosphere might be thinking "it's saturated", the surface can tell that the IR effect is increasing.
In another simliarity, although the viewer of the car can't see headlights at 100m, they do see light (let's do the thought experiment on a dark road at night). Brighter headlights won't help the viewer see the headlights, but the fog-light will increase. Just the same, as the earth's surface temperature increases, you still won't see direct IR loss to space, but the total IR transfer upwards can increase.
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howardlee at 06:29 AM on 14 October 2014The long hot tail of global warming - new thinking on the Eocene greenhouse climate
Fairoakien - it all about the timescales.
The shortest limb of the shortest orbital wobble is about 10,000 years. Human-caused GW is just a couple of centuries - just 2-3% of that. Also, we are on a cooling part of the orbital cycle, not warming.
Orbital cycles modifying climate is not at all new, what is new is the precision of dating which allows detailed sedimentary records across the globe to be compared with greater precision than ever before. The new thinking in the articles I revewed is that even in the Eocene the orbital cycles are not special, which refocuses attention on other, non-orbital causes to turn a cooling climate into a warming climate.
Globally every year volcanoes (including undersea volcanoes) only emit about as much CO2 as a single state like Ohio or Michigan does. The combined volcanic output of CO2 averages at around 260 million tonnes per year compared to about 35 billion tonnes of human-produced CO2 annually. Even the major volcanic eruption of Mount Pinatubo in 1991 only produced about 50 million tonnes of CO2. Human CO2 emissions are equivalent to an extra 11,200 Kīlauea volcanoes or about 360 more mid-ocean ridges!
Large Igneous Provinces are in a league of their own,- see this post, but there hasn't been one for 16 million years.
The "GW" about 1100 years ago is a bit of a myth from old data. Newer, more precise measurements show that since the industrial era we have reversed 6,000 years of that natural orbital cooling in just a century. Contrary to the myth, the planet is hotter now than the Medieval Warm Period (AD 800-1300AD) or the Roman Warm Period (500BC to 400AD), or any time in the last 6,000 years. Even 6,000 years ago, during the “Mid Holocene Warm Period,” when a warmer climate was caused by the same orbital/insolation change that ended the last ice age, global temperatures were about the same as the 2000s.
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CO2 effect is saturated
Rob Honeycutt - As I noted in a long ago comment here, you have to be very careful about reasoning from an analogy back towards a complex system that the analogy is trying to explain. In general the mapping from the complex system is only part of that system to one of the analogy relationships (forward mapping), and taking the analogy as 100% identity capable of outlining issues with the complex system (backward mapping) is an error. That's an incorrect use of analogy.
Far better to examine issues in the actual problem domain, as with the Myhre et al 1998 reference above - line by line radiative codes backed by detailed spectral data, later confirmed by satellite observations. Those are not amenable to nor contradicted by simple analogical reasoning and back of the envelope calculations.
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howardlee at 05:23 AM on 14 October 2014The long hot tail of global warming - new thinking on the Eocene greenhouse climate
MA Rodger - the accelleration of the Indian Plate seems to have been due to the interaction with the Reunion-Deccan mantle plume which pushed the Indian plate faster for a while. The Indian lithosphere is indeed fairly thin probably due to it's encounter with the plume. The traps are the result of enormous flood basalt eruptions, in common with other traps like the Siberian Traps, which are also associated with abrupt climate change.
So the speed of motion is not due to the thin crust, but both are due to the interaction of the Indian Plate with the Reunion-Deccan Mantle Plume.
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Fairoakien at 04:57 AM on 14 October 2014The long hot tail of global warming - new thinking on the Eocene greenhouse climate
How come when the GW skeptics indicated that GW could be caused by natural cause e.g. global tilt or wobble and by volcanic release of CO2 it was ridiculed. But now these are used as new science supporting GW.
I still would like to know what caused the GW of 1100 years ago. During that period the earth was about as hot as it was in 2000. The startof the most recent leveling off of global warmimh. See NOAA chart on earth and sea heat
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cosmicomics at 04:45 AM on 14 October 2014How did the UK grid respond to losing a few nuclear reactors?
In comment 28 I wrote:
“The Danish Energy Agency recently found that onshore wind was the cheapest way for Denmark to generate additional electricity.”
A new EU report has reached a similar conclusion:
“Onshore wind is cheaper than coal, gas or nuclear energy when the costs of ‘external’ factors like air quality, human toxicity and climate change are taken into account, according to an EU analysis.
The report says that for every megawatt hour (MW/h) of electricity generated, onshore wind costs roughly €105 (£83) per MW/h, compared to gas and coal which can cost up to around €164 and €233 per MW/h, respectively.
Nuclear power, offshore wind and solar energy are all comparably inexpensive generators, at roughly €125 per MW/h.” -
Rob Honeycutt at 01:36 AM on 14 October 2014CO2 effect is saturated
I don't know if Tom or KR has watched Jonathan's video, but I think there's a bit of an issue in how he's approaching the questions he's bringing up. But I don't know enough of the detailed science to address it.
At one point, while reading through the SkS material above, he comes to a point where the author starts applying a metaphor for how radiative absorption operates. But then Jonathan skips that metaphor and applies his own metaphor, one where he likens visible light to IR and CO2 to fog. In other words, he's trying to think of radiative absorption as similar to car headlights in the fog.
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MA Rodger at 01:27 AM on 14 October 2014The long hot tail of global warming - new thinking on the Eocene greenhouse climate
Concerning the speed of the Indian plate, it is known to have travelled far faster that the other fragments of Gondwanaland and also to be thinner than the other fragments of Gondwanaland. My understanding is that the speed being the result of the thin crust is widely accepted and that the Traps are the result of that thinning process. From what I can gather, the inferred thinning process being due to the mantle plume that broke Gondwanaland apart remains hypothesis.
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CO2 effect is saturated
Jonathan Doolin - I think I see some of the issues here; the image you are referring to is, well, a bit misleading in presentation.
A more detailed graph shows not just the results of atmospheric absorption on incoming and outgoing radiation, in a more clear fashion shows what would be expected for an Earth without an atmosphere (at the same temperatures):
Here you can more clearly see the absorption ranges for water vapor and CO2 that result in the more detailed spectra Tom Curtis linked. And see clearly the range of IR reduced by the greenhouse effect.
Quite frankly, the rather cartoon representation in the graph you linked gives the (incorrect) impression that the colored band is the sum radiation, wholly unaffected by GHG absorption, when in reality that band region is a complex spectra of what's left after passing through an atmosphere containing those GHGs. I consider your graph less than useful as a result.
As noted here and elsewhere, absorption of IR is effectively saturated near the ground at sea-level pressures, with the average absorption path length being quite short (in the order of meters). The more telling altitude is, however, that of effective radiation (roughly where half the radiated IR escapes to space without reabsorption). And that altitude rises as GHG concentrations increase, to cooler altitudes (by the lapse rate) that will radiate less energy. IR escapes across the thermal blackbody spectral range - but at levels determined by the temperature of where it radiates.
If you want to play with the math, I would suggest both looking into the freely available copies of MODTRAN as well as reading Myhre et al 1998, where they used line-by-line radiation codes for multiple locations (you cannot get correct global results by looking at a single locations, such as the Barrow atmospheric column) to compute the effective direct forcing change for 2x CO2, which results in the simplified formula:
ΔF = 5.35*ln(C/C0)
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howardlee at 23:56 PM on 13 October 2014The long hot tail of global warming - new thinking on the Eocene greenhouse climate
Hi Pluvial,
If I understand you correctly, you are suggesting that climate drives tectonics via glacially-controlled isostatic ‘pumping’ of the crust and mantle. It’s an intriguing idea, but as you yourself say, this is an unusual perspective, and not mainstream science. I’d have to research that idea more, but here are my immediate thoughts:
I’m not an expert on mantle dynamics, but I can visualize your concept and I can imagine it having perhaps some effect around regions experiencing strong and repeated isostatic loading as demonstrated in Scandinavia. Repeated depression/elevation of the lithosphere might conceivably contribute to delamination – but I’m no expert there. I’m not sure how important that effect can be, though, as we had active tectonics in ice-cap-free greenhouse eras like the Mesozoic and the Eocene.
Tectonics is driven by the convecting mantle and the sinking of cold, dense plate slabs in subduction zones, with slow upwelling of mantle displaced by that sinking material. The energy driving tectonics is radioactive decay and the cooling of the planet, transferring heat energy from the core and mantle, very slowly, through the crust and atmosphere to space. The energy is immense, but only a tiny portion of that energy ‘leaks’ from the geosphere to the climate system. So the direct thermal energy transfer from the geosphere to the climate is small, much smaller than the energy powering tectonics within the mantle and core.
But tectonics does not drive climate by a direct thermal process. The main long-term effect of tectonics on climate is through the delicate balance between silicate weathering removing CO2 (via mountain building and erosion) and volcanic production adding CO2 (principally subduction over millions of years).
You refer to climate change associated with India’s motion northwards. I think you are referring to the Deccan Traps eruptions at the end of the Cretaceous. Those eruptions were a class of eruption called “Large Igneous Provinces” (it is a bit misleading to call them volcanic because they are so much bigger than any volcano the Earth has seen in the last 16 million years). They did indeed trigger abrupt climate change which triggered a strong extinction event just before the impact that wiped out the dinosaurs. The North Atlantic Igneous province associated with the Eocene hothouse is also a LIP.
You suggest that glacially-controlled isostatic pumping pushed continents away from Antarctica. For me the timing doesn’t match and the plate motions don’t fit. The separation of Africa from Antarctica began in the Jurassic, when there was negligible ice cover on Antarctica. Australia/Tasmania and South America finally broke with Australia at the Eocene Oligocene transition again at a time when Antarctica was essentially free of ice. While the motions of Australia and Africa are northward, the motion of South America is westward. Also, during the Messinian Salinity Crisis, where there’s evidence of strong isostatic motion due to salt accumulation, continents did not move away from the locus of isostatic load (the Mediterranean), they continued to converge.
Your last point linking dams to seismicity is a well-researched topic. Basically all the crust is under stress all the time. When that stress exceeds the strength of the rock it breaks, causing tremors or earthquakes (leaving aside ductile failure for now). Increasing water pressure in groundwater can counteract the pressure keeping 2 sides of a fault locked, making it easier for the fault to move and cause a tremor. It’s the same physics that is associated with fracking. Isostatic unloading has indeed induced seismicity, as you suggest, for example in Scandinavia.
You raise an interesting idea, though, and the interaction of isostatic loading and plate tectonics makes sense, though I’m not sure it can be a driver so much as a localized modifier.
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DSL at 23:01 PM on 13 October 2014CO2 effect is saturated
Evans & Puckrin 2006 might be helpful, Jonathan.
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CBDunkerson at 21:43 PM on 13 October 20142013 SkS Weekly News Roundup #27B
The thing which always gets me about the fracking industry's desperate attempts to claim the technology doesn't cause earthquakes (or since that has now clearly been proven false, that it doesn't cause 'major' earthquakes) is that the 'earthquake causing' may be the only 'good' thing about fracking.
Yes, fracking causes thousands of small quakes. To me it seems very likely that those small quakes in turn contribute to shaking loose larger fault lines and triggering bigger quakes. However, that's all a good thing. Sooner or later faults will slip. Fracking causes them to do so sooner... which means less energy is built up and the quakes are smaller and with fewer aftershocks than they would have been eventually. We should be studying fracking as a potential future means of 'earthquake management'.
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michael sweet at 19:57 PM on 13 October 2014CO2 effect is saturated
Tom,
Does it make a difference when the spectrum was measured over Barrow? I cannot do the calculation, but it strikes me that in the winter there would be a different amout of radiation lost to space than during the summer. In the tropics the radiation would be more constant, but might not give as clear a spectrum.
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Tom Curtis at 16:44 PM on 13 October 20142013 SkS Weekly News Roundup #27B
scaddenp @6, given a moderately recent discussion on Yamal, I am easilly convinced that the methane is biogenic. As you note, however, that does not mean the increased groundwater contamination is not a result of fracking. Indeed, given timing and the effect of fracking on earth quakes it seems very plausible that fracking has caused faulting which connects the biogenic methane to the ground water.
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Tom Curtis at 16:34 PM on 13 October 2014CO2 effect is saturated
Jonathan Doolin @294:
1) The formula you used is for wavelength. That is, for a graph with a constant scale per unit wavelength, it shows the point with the highest value by wavelength. For 320 K, I work out that wavelength to be 9 micrometers, which is equivalent to a wavenumber of 1100 cm-1. For a graph with a constant scale for units of frequency, however, you should use νmax = 5.879 x 1010 x T, or 18.8*10^12 Hertz. Converted into wavenumbers, that is 627 cm-1.
The reason for the difference is that one unit wavenumber corresponds to more units of wavelength at 627 cm-1 than at 1100 cm-1. Therefore the area shown under the graph at 627 cm-1 must be divided among more units wavelength. To retain the same area, it must show a correspondingly lower intensity per unit.
The graph you originally linked to does actually show a long tail over the 15 micrometer peak absorption band for CO2, so that the upper curve may not be a mistake per se. The red band, however, is deliberately drawn to exclude that peak even though it lies in the emission band and is fundamentally important. Further, by using a wavelength scale, the CO2 band is placed on the wings where it is hard to judge its impact. That impact will in fact be the same no matter whether you use a frequency or wavelength scale, and as can be seen on the frequency scale (wave number) is very important.
In any event, I do not believe Wein's law to be an approximation, but of necessity it takes different forms for frequency and wavelength.
2) I have not repeated your calculation for the Barrow figure, but it sounds like it is in the correct ball park.
Looking at the downward from space figure, you can see that in the absence of CO2 (and ignoring water vapour and clouds), the radiation to space around 666 cm-1 would follow the black body curve for 268 K, that is over the absorption band for CO2 it would have the same intensity as the downward radiation at the surface (or actually very slightly more). Therefore, the presence of CO2 at that location has a warming effect of, using your calculation, around 45 W/m^2. In fact, water vapour would create some of that warming because it does overlap, but at a lower and warme altitude. Consequently its effect in the absence of CO2 would be less than that of CO2. Therefore the warming effect of CO2 at that location at that time was probably closer to 20 W/m^2, and is impossible to calculate without a full fledged radiation model.
It is often noted that water vapour has a greater greenhouse effect than CO2. That, however, is because it has a lesser effect across a far wider band of frequencies. In the frequency in which CO2 is active, CO2 has the stronger effect. (Of course, water vapour only has any effect because the atmosphere is warm enough to evaporate, and without the warming contribution of CO2 that would not be the case, or almost entirely not the case. Therefore CO2 drives temperatures more than water vapour, even though it has the weaker greenhouse effect.)
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Jonathan Doolin at 13:52 PM on 13 October 2014CO2 effect is saturated
Hello. I found the graphs from Barrow Alaska very helpful.
The graphs from Barrow make it seem that Carbon Dioxide operates like a blackbody in wavelengths near 15 micrometers (667/cm) and is transparent in (most) other wavelengths.
Looking up, in the 600/cm - 760/cm range, there is roughly 100 milliWatt's per (square meter • steradian • cm^-1). Looking down, there's only 50. There is a much higher photon count in that range looking up than there is looking down.I did a little calculation using these numbers; based on the units of the vertical and horizontal parts of the Barrow Alaska graph... I could draw a little rectangle 100 high and 150/cm wide.
This rectangle would have an area of 15,000 milliWatt per (square meter • steradian). I would multiply by the area of the entire sky in steradians, which is about 6.25. which comes out to about 93.75 Watts per square meter.
----The graph that I referenced was not directly from joannova, but was from comment #58 at http://joannenova.com.au/2010/02/4-carbon-dioxide-is-already-absorbing-almost-all-it-can/
which in turn comes from http://theresilientearth.com/?q=content/why-i-am-global-warming-skeptic
Except for the color, this seems identical to the graph here.
http://noconsensus.wordpress.com/2010/04/19/radiative-physics-yes-co2-does-create-warming/What has been changed is that the infrared spectrum of Earth has been added.
Wein's Law says that lambda_peak * Temperature = .0029 meter • Kelvin
But what temperature should you use? 290 Kelvin yields a peak wavelength around 10 micrometers. When I did this earlier today, I thought the resilientEarth graph was too far to the left... (Using a temperature near 325 Kelvin, perhaps--like the Sahara.) However, the Sahara graph has a peak elsewhere, I think... Is Wein's Law an approximation that doesn't work at these temperatures?
======
I worked a good portion of the morning making another video, but unfortunately the screen-capture program crashed. These weren't the only things I addressed but seemed worth mentioning.
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scaddenp at 13:26 PM on 13 October 20142013 SkS Weekly News Roundup #27B
Tom, I havent followed this closely but I am pretty sure studies showed the gas was biogenic and not from fracking. This doesnt of course rule out the possibility that engineering associated with fracking hasnt created disturbanced biogenic sources. It does show more caution is needed in determining causes.
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Tom Curtis at 12:39 PM on 13 October 20142013 SkS Weekly News Roundup #27B
Of particular interest is the bit at the end in which the lady notes that prior to fracking in the region, methane concentrations in the water were very low. To be very clear, it is possible for methane to enter groundwater naturally, and end up in water systems as a result. That has happened before prior to fracking. However, the argument that because it has happened before without fracking, the more recent occurences which are more frequent near fracking sites and where groundwater contamination prior to fracking was low cannot be due to fracking is a straight forward fallacy.
Re earthquakes:
According to the USGS:
"USGS statistically analyzed the recent earthquake rate changes and found that they do not seem to be due to typical, random fluctuations in natural seismicity rates. Significant changes in both the background rate of events and earthquake triggers needed to have occurred in order to explain the increases in seismicity, which is not typically observed when modeling natural earthquakes.
The analysis suggests that a likely contributing factor to the increase in earthquakes is triggering by wastewater injected into deep geologic formations. This phenomenon is known as injection-induced seismicity, which has been documented for nearly half a century, with new cases identified recently in Arkansas, Ohio, Texas and Colorado. A recent publication by the USGS suggests that a magnitude 5.0 foreshock to the 2011 Prague, Okla., earthquake was human-induced by fluid injection; that earthquake may have then triggered the mainshock and its aftershocks. OGS studies also indicate that some of the earthquakes in Oklahoma are due to fluid injection. The OGS and USGS continue to study the Prague earthquake sequence in relation to nearby injection activities."
It should be noted that fluid injection can only cause earthquakes where there are stress points along fault lines. The quakes relieve that stress. Therefore the very high rate of earthquakes is probably due to facking, but after an unknown number of years the rate will probably fall again, possibly to below the pre-fracking level. That does not make the recent upsurge in earthquakes a good thing, but the growth in earthquake numbers is not simply pojectable into the future, even with continued fracking.
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Tom Curtis at 11:57 AM on 13 October 2014Volcanoes emit more CO2 than humans
LuisC @262, cooler water absorbs more CO2 than warmer water. That is why soft drinks give of CO2 as they warm. The volcanic cooling due to aerosols sufficiently cools the surface ocean that the oceans absorb more CO2 than the volcanoes emit. Consequently the statement you quote is typically true. (Coincidence of a strong El Nino with a volcano can cancel this effect.)
While the statement is true and does emphasize the small amount of total volcanic emissions, not to much should be read into it. In particular, as the ocean warms with the passing of the volcanic aerosols, the excess CO2 emited by the volcano will be outgassed by the warming oceans (or at least, 55% of it will, as with human emissions). Therefore the volcanic cooling has no long term effect. The volcanic emissions, particularly those of a single volcano remain small in annual terms relative to anthropogenic emissions.
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michael sweet at 10:23 AM on 13 October 20142013 SkS Weekly News Roundup #27B
Linus,
Googling "Oklahoma Earthquakes" yields this:
"4 earthquakes today35 earthquakes in the past 7 days131 earthquakes in the past month1,125 earthquakes in the past year"
They didn't have earthquakes before fracking. Many of the chemicals they use are known carcinogens (they keep the formulas secret partially for that reason) and there have been many recent news articles one of many (Business News of Dallas) about contaminated water. Perhaps you should google your key words and see what you find. Where did you hear these false claims? Why did you believe them?
I doubt Josh Fox has responded to his critics, it is a waste of time. The new data releases have proved him correct. Much of this data was hidden before his documentary.
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CBDunkerson at 09:45 AM on 13 October 20142014 SkS Weekly News Roundup #41B
Mike: It isn't so much that people are 'ruling out' effective CCS as that it doesn't exist. Similarly, no one is 'ruling out' cold fusion, cheap fission power, or any other hypothetical future development. However, until these things are actually developed and utilized there isn't any point factoring them in to analyses. There are billions of things that might happen. Most of them won't.
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Joel_Huberman at 09:42 AM on 13 October 20142014 SkS Weekly News Roundup #41B
Speaking of typoes, "epergy" in the first headline should be corrected to "energy".
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LuisC at 08:15 AM on 13 October 20142013 SkS Weekly News Roundup #27B
Haven't Josh Fox's particular claims about fracking (eg. that it ''causes cancer'' and ''earthquakes'', and that it ''contaminates water''), as expouded in his documentary ''Gasland'', been severely criticized and called into question by the testimony of the very community he was focusing on, as well as the EPA and the scientific community itself? Has he responded to the points raised by his critics? I would be very interested in reading his response.
Moderator Response:[PS] Much better. :-)
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wili at 06:31 AM on 13 October 20142014 SkS Weekly News Roundup #41B
The CC headline: "The $9.7 tillion problem: Cyclones and climate change" should read 'trillion.'
Recall that coal does other ecological damage than just CO2 emissions. In any case, CCS remains elusive. We've been hearing about its promise for about 20 years, yet there are only one or two plants in the world doing it seriously so far, iirc.
Burning coal must be seen as equivalent to atmospheric testing of nuclear weapons--something to be avoided for all concerned.Moderator Response:[JH] Typo corrected. Thank you.
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LuisC at 05:29 AM on 13 October 20142013 SkS Weekly News Roundup #27B
Isn't Josh Fox a demonstrated liar?
Moderator Response:[PS] Please read and conform to the comments policy. (eg No accusations of deception.)
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LuisC at 05:25 AM on 13 October 2014Volcanoes emit more CO2 than humans
This sentence doesn't seem to make any sense:
''In fact, the rate of change of CO2 levels actually drops slightly after a volcanic eruption, possibly due to the cooling effect of aerosols.''
Shouldn't that read ''...the rate of temperature increase actually drops slightly after a volcanic eruption, possibly due to the cooling effect of aerosols.''? -
scaddenp at 04:42 AM on 13 October 20142014 SkS Weekly News Roundup #41B
Jimb. The no. one issue for CO2 reduction is eliminating coal power stations. We have enough coal to seriously damage climate - much more so than oil. I dont think there is any CCS promoter that thinks CCS is "the answer". The issues with it are large, but there is also a lot of work going into solving them. There is absolutely no doubt that CCS makes energy generation more expensive. So do carbon taxes and similar schemes. If the problems can be solved, then there may well be situations where coal + CCS is a more economic solution then any other alternative. With appropriate costing of CO2, you can let the market make that decision.
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DSL at 04:39 AM on 13 October 20142014 SkS Weekly News Roundup #41B
GIS L-OTI for September is out: .77C. The warmest September on record and the 7th warmest month in the record. 2014 is now just a smidgen below 2010 and 2005 for warmest year. August/September MEI = .500.
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jimb at 02:56 AM on 13 October 20142014 SkS Weekly News Roundup #41B
CCS is still an idea in search of money.Even if CCS is deployed widely, it cannot capture CO2 from fossil fuel dependant things such as cars, trucks, trains, airplanes ships, home heating systems etc. How long are you willing to wait for the role of CCS to be less 'uncertain'?
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What's the role of the deep ocean in global warming? Climate contrarians get this wrong
#1 StBarnabas:
Good point!
I used this water density calculator to create the graph below showing how one kilogram of sea water expands with temperature. Note that the expansion per °C of warming doubles from 0°C to 5°C and nearly doubles again from 5°C to 15°C.
I wonder if the nearly constant sea level rise the last two decades despite increased melting of land ice can partly be explained by this difference in thermal expansion. If some of the ocean heat uptake during the last 20 years has shifted from the shallow and warm parts to the deeper and colder parts this would reduce the total thermal expansion even if the total heat flux into the oceans remained the same. (not all Joules of OHC is equal!) This reduced thermal expansion may have offset the increased sea level rise from melting ice sheets, but that situation won’t last. Either changes in the ocean circulation will lead to more upper ocean warming again, or increased melting of land ice will overwhelm the reduced thermal expansion and accelerate the sea level rise.
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Mike3267 at 00:41 AM on 13 October 20142014 SkS Weekly News Roundup #41B
It is not necessarly the case that we "need to phase out fossil fuels," as stated in the opening sentence of the first story above. The need is to phase out GHG emissions, especially CO2. What role CCS will play is this is uncertain, but climate activists should be warry of alienating people needlessly.
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Christopher Gyles at 07:02 AM on 12 October 2014What's the role of the deep ocean in global warming? Climate contrarians get this wrong
Okay, the "deep" ocean and the "abyssal" ocean are the same thing--but is the "deeep" ocean even deeeper than that? :)
Rob Painting @ 4
Looking forward to the three-tiered rebuttal.
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cosmicomics at 06:59 AM on 12 October 2014How did the UK grid respond to losing a few nuclear reactors?
michael sweet
The new Swedish government was formed on 2 October. It's a minority government consisting of Socialdemokraterna (S) and Miljöpartiet (MP), the environmentalist party. The decision concerning nuclear power isn't directly to close the plants, but to make demands that will affect the profitability of some of the oldest plants, thereby causing them to close down.
(I stedet for konkret at gå efter lukning af bestemte reaktorer kommer energiaftalens øgede sikkerhedskrav og forhøjede kerneaffaldsafgift fra 2,2 til 3,8 øre pr. kilowatttime ifølge Miljøpartiet til at betyde, at de fire ældste reaktorer lukker.)A spokesman for MP said that a parliamentary majority wouldn't be hard to find.
(Det bliver ikke svært at finde flertal for det i Riksdagen, fortæller Miljøpartiets talerør, Åsa Romson.)The aim is to increase last year's renewable production of 18 TWh to 30 in 2020.
(S og MP er blevet enige om, at mindst 30 terawatttimer (TWh) el i 2020 skal komme fra vedvarende kilder. Sidste år var det 18 TWh, og det nuværende mål er 25 Twh.)
(Danish quotes from Knockout..., cited above.)In the French case the difference is that what before was intention has now become law.
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michael sweet at 03:28 AM on 12 October 2014How did the UK grid respond to losing a few nuclear reactors?
Cosmicomics,
Thanks for the references. It appears France announced that they are pulling back on nuclear last June. I am surprised no one mentioned it before on this thread. They have undoubtedly considered their neighbors successes and failures with renewables and the nuclear build they are currently doing in Finland.
It looks like Sweden might be more of a political move The Greens wanted nuclear out as part of an agreement to join the government. Perhaps that could be reversed in the future if nuclear pans out.
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Dikran Marsupial at 23:04 PM on 11 October 20142014 SkS Weekly Digest #36
Dr McKitrick wrote "instead I was aiming to measure how far back the hiatus apparently started."
his method clearly doesn't do that. Here is a plot of the RSS data, along with trend lines showing the trend over the whole period, and the trend over the last 26 years, which McKitrick claims to be "trendless" according to his test:
There doesn't seem any evidence whatsoever of any change in the rate of warming starting in 1988 (a decade later perhaps), and the trend since 1988 is almost exactly the same as the long term trend.
The problem is that Dr McKitrick simply doesn't understand that a failure to reject the null hypothesis does not mean that the null hypothesis is probably true, and never has done.
All Dr McKitrick needed to do to see this problem was to plot the data with the trendlines, and it is pretty hard to understand why he obviously failed to perform that basic sanity check before publishing a journal papers (although perhaps it explains the choice of journal).
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cosmicomics at 21:56 PM on 11 October 2014How did the UK grid respond to losing a few nuclear reactors?
Re. Sweden:
Headline:
Knockout til svensk atomkraft: Nye reaktorer droppes, og gamle må lukke
(Swedish nuclear energy knockout: New reactors dropped, old ones to shut down)Headline:
Sverige overhaler Danmark på vindkraft i 2014
Sverige har færre, men større vindmøller og regner med at have mere kapacitet end Danmark, når året er omme.
(Swedish wind power to pass Denmark's in 2014
Sweden has fewer, but larger turbines, and expects to have more capacity than Denmark when the year is over)I haven't tried to find articles in English. The bit about Sweden passing Denmark would interest Danish readers, but probably not most others. Articles about the reductions in English could probably be found with appropriate search terms.
Re. France:
I heard the news on Danish radio yesterday, but here are some corroborating links: 1, 2, 3.
I hope the links work (first time I've tried to do it this way) and that you find the information useful.
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KeefeandAmanda at 20:02 PM on 11 October 2014What's the role of the deep ocean in global warming? Climate contrarians get this wrong
I have some questions about the numbers that Greg Laden gave. He wrote [with my modifications for ascii text]:
"One of the key numbers is the energy imbalance where the ocean absorbs extra AGW produced heat. Energy imbalance is measured in terms of Watts per m^2. The present study yields a value of 0.72. A previous study reported 0.54. Other estimates have varied in this range. Llovel et al point out, however, that these differences may be due to differences in the ocean depth considered in each study and the time periods covered."
Before I ask these questions, I would like to quote what one named "BBD" said in the comments toward the end of the comments section at October 8, 2014 at 6:58 PM
for the article "A lot more heat is found in the ocean" posted Wed Oct 8 20154 at the site HotWhopper:
http://blog.hotwhopper.com/2014/10/a-lot-more-heat-is-found-in-ocean.html
Here is the quote from BBD's comment [with my modifications for ascii text]:
"...Nobody has claimed all of the extra heat has gone there although some of it obviously has. I hope you take the point, sloppy language here is encouraging sloppy thinking.
From Llovel14:
Therefore, we estimate the heat uptake by the upper 2,000m of the global ocean to be 0.72 +- 0.1 W m^2. Our estimate is slightly larger than the recently reported estimate of 0.54 +- 0.1 W m^2 for the upper 1,500 m layer computed over 2005-2010 and the estimate of 0.56 W m^2 for the 0-1,800 m layer over 2004-2011
The planetary energy imbalance is ~0.6 - 0.7W/m^2, so the OHU estimate in L14 would seem to account for all of it."
The first paragraph above seems to be a direct quote from the Llovel paper itself. The context of this comment above by BBD seems to be on Trenberth's "missing heat" that those who reject mainstream climate science say is still missing. But BBD seems to say that via the given numbers, seemingly directly from the Llovel paper itself, this paper more than closes the gap and so therefore there is no more "missing heat" problem.
My questions are mainly to those who have access to the paper itself:
Are Laden and BBD using the term "energy balance" differently or applied to different things? BBD says, "The planetary energy imbalance is ~0.6 - 0.7W/m^2" while Laden says, "Energy imbalance is measured in terms of Watts per m^2. The present study yields a value of 0.72." But the Llovel paper according to the above quote from the paper uses the term "heat uptake" for the 0.72 +- 0.1 W m^2 measure.
Also, BBD seems to say that since 0.72 is greater than the range ~0.6-0.7, Trenberth's "missing heat" is more than covered by the 0.72 +- 0.1 W m^2 heat uptake (as the paper puts it). Is BBD saying this and if so, is BBD right - does the Llovel paper do this and say this in this quote above from that paper?
Please, would someone with the requisite knowledge and access to the paper answer these questions and clear all this up? (And please feel free to include mathematically oriented information.)
Moderator Response:[PS] Fixed links
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Andy Skuce at 19:04 PM on 11 October 2014What's the role of the deep ocean in global warming? Climate contrarians get this wrong
Smith@2
From the Llovel paper:
"Nevertheless, the ocean layers above 700 m and 2,000 m represent only 20% and 50%, respectively, of the total ocean volume."
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Rob Painting at 14:58 PM on 11 October 2014What's the role of the deep ocean in global warming? Climate contrarians get this wrong
victorag - The uncertainty range in the Llovel paper is many times larger than their estimate, but from a physically-based perspective one has to wonder why, if the abyssal cooling trend is correct, geothermal warming in the abyssal ocean appears to stopped stone-cold dead. We would expect geothermal activity to be still be going on down in the very deepest parts of the ocean, as it's a component of the thermohaline circulation.
As for continued global warming (aka the pause):
And the remaining 1% which is warming the atmosphere:
The RSS satellite data appears to be the odd one out. We'll need more data to say for sure, but it looks like the atmosphere is still warming too, albeit at a slower rate than the previous two decades. SkS has a three-tiered rebuttal to this myth in the works.
That the climate models are remarkably close to the observed temperature trend over the recent decade, taking into consideration all relevant factors, is an explicit demonstration that we can get this temporary surface temperature slowdown even when the Earth's climate sensitivity is around 3°C per doubling of CO2.
As for climate policy, one needs to consider the ecological and agricultural impacts of warming and ocean acidification if one expects to be taken seriously.
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