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Comments 9601 to 9650:
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JWRebel at 04:15 AM on 27 September 2019CSLDF: Events at NOAA Highlight Strengths and Shortcomings of Agency Scientific Integrity Policies
I don't think this Dorian gaffe is a strong example, perhaps the weakest of the many serious instances in which this Administration has been trying to alter/silence/stop scientific voices, albeit probably the most well-known. The black cone was obviously a home-made extension of the official cone in the direction the hurricane seemed to be going, and not a "doctored" or "counterfeit" version, and Alabama was simply an amateuristic but not crazy or malign extrapolation. NOAA should have stuck to their forecasts without correcting Trump or entering into a dialogue with his Tweets. An official agency should simply ignore what other people are saying, especially if there might be a political angle to it. If reporters ask, just tell them: "No, not Alabama" without implying "There you have the dufus president going off like a loose cannon again", despite the latter also being a true statement (but not a meterological fact).
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MA Rodger at 00:01 AM on 27 September 2019CO2 effect is saturated
PringlesX @563,
The usual 'adding layers of insulation' analogy only works so far. It is the reduced temperature at the altitude where the IR emits into space that sits at the heart of the AGW mechanism. This is thus not akin to an extra insulating layer which maintains the outside layer temperature and boosts the inner layer temperature with more layers. Your idea of leaky outer insulation @549, or perhaps a space blanked backed by insulation layers, may be a way to a better physical representation in the analogy, but I'm not entirely sure it would greatly assist understanding.
Concerning a 'lecture', it depends if you are just describing the actual GHG mechanism (which would on its own take about 3 minutes to fully explain) or an actual 'lecture' which can be usefully stretched to include background stuff like the S-B relationship, Planck spectrum, depth of the atmosphere, IR path-lengths, outward radiation at the TOA, why GHGs are GHGs, why they operate at particular wavelengths, etc; stuff you are probably already familiar with.
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PringlesX at 20:02 PM on 26 September 2019CO2 effect is saturated
Scaddenp:
Analogies are a tool for promoting understanding by transferring understanding from a known process into a new area where the elements of the analogy are applicable.
They are especially useful for explaing things to people who lack the technical background to work through real process.I agree 100%. So is it possible in this case? If you were to have a lecture for a room of people with different backgrounds. What would you say is happening going from 285ppm to 400ppm to 500ppm?
Thanks in advance. -
PringlesX at 20:00 PM on 26 September 2019CO2 effect is saturated
Pringlesx,
It seems to me that your analogy fails becasue you used way too many sleeping bags. (100 bags with doubling CO2 equal to the hundredth bag).
A better analogy would be one sleeping bag with doubling CO2 equal to another bag.It has been demonstrated that the difference is happening in the TOA. The transmission layer. And the CO2 is saturated in its absorption band. And the athmosphere is not only CO2, GHE is mostly due to water vapour.
So go from one sleeping bag into two sleeping bags is very off. -
PringlesX at 19:53 PM on 26 September 2019CO2 effect is saturated
What you cannot do is disapprove a theory by inappropriate use of an analogy.
How do you feel about that the whole tread starts of with using an analogy of a water tank.
"Lets think about a simple analogy: We have a water tank."
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MA Rodger at 18:15 PM on 26 September 2019Climate's changed before
TVC15 @780,
Sea level during previous intergalacials has been the subject denialist blather preented on this thread before. This version is a little different from that @715 & @780 which asserted that all eight previous interglacials saw sea level metres above today's level. Of course there are only two previous interglacials that saw such sea levels - the Eemian (MIS-5e) and 400,000y bp the MIS-11.
The Eemian was significantly warmer than today in northern latitudes. The link @780 states the temperature became +8ºC warmer than today in northern Greenland. So if temperatures do rise like that, we should expect significant SLR. The denialist appears to be saying that such temperatures are going to arise naturally. Of course, all interglacials are different. That is why only two of the last eight had sea level higher than today.
MIS-11 is interesting because it was of longer duration than other interglacials. This resulted from the milankovitch cycle that triggered the interglacial being followed 20,000 years later by a stronger peak in the cycling extending the interglacial accordingly. A comparison of MIS-11 & the present Holocene is provided by Rohling et al (2010). The milankovitch cycles do not provide that extra boost for the Holocene so again there is no reason to have expected 20,000 more years of interglacial with sea level increasing above today's levels - not without AGW.
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TVC15 at 14:53 PM on 26 September 2019Climate's changed before
I meant angle!
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TVC15 at 14:52 PM on 26 September 2019Climate's changed before
@ 781 scaddenp,
Yes indeed what the heck! This denier portrays himself as being scintifically literate but he does not have me fooled. He's pompous and always results to insulting anyone's intelligence if they challenge the rubbish he put out.
That's a great angel you provide in asking does he think the causes of SL rise and ice melt from the past are the result of the forcing's at work today.
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scaddenp at 13:16 PM on 26 September 2019Climate's changed before
What the heck indeed. That they confuse MIS-11 with the Emenian maybe? That they think causes of sealevel rise and ice melt in past are the same as the forcing at work today?
Or more likely: their beliefs are not based on any rational analysis and that they are making 2+2=5 with motivated reasoning.
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scaddenp at 13:04 PM on 26 September 2019Animal agriculture and eating meat are the biggest causes of global warming
Depended a bit on your definition of "underdeveloped" for both exporters and importers.
Export trade accounts for about 10% of meat production. Across all meats, exports (mt) 2017 are: (Source)
World 32711
United States 7718
Brazil 7023
EU 4983
Australia 1905
Canada 1897
India 1736
Thailand 1113
New Zealand 991
China 590
Argentina 554and top Importers are:
China 5423
Japan 3635
United States 2195
Mexico 2167
Viet Nam 1667
Korea Rep of 1317
Russian Fed. 1290
EU 1286
Saudi Arabia 976
Canada 762 -
BTGovier at 11:47 AM on 26 September 2019Animal agriculture and eating meat are the biggest causes of global warming
Skeptical Science, you mentioned “... less in developed countries (e.g. 3% in the USA)”. But how much of the meat consumed in developed countries comes from undeveloped countri?
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scaddenp at 11:10 AM on 26 September 2019CO2 effect is saturated
Analogies are a tool for promoting understanding by transferring understanding from a known process into a new area where the elements of the analogy are applicable. They are especially useful for explaing things to people who lack the technical background to work through real process.
What you cannot do is disapprove a theory by inappropriate use of an analogy.
If you want to prove some theory is wrong, then you need to show that correct application of the theory results in predictions that are incompatible with observation. Radiative theory so far spectacularly matches observation. You need to focus on understanding rather than looking for some reason to dismiss science.
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Eclectic at 10:34 AM on 26 September 2019Was Greenland really green in the past?
JDG @31 ,
I certainly agree with your last paragraph. (But not so much your final sentence ~ "boom and bust" sounds like a business sector. The Greenland Viking saga was closer to "extinction event". )
From a climate point of view, it was a rather small decline in temperatures from the Medieval Warm Period . . . and it should not have been enough to extinguish the Viking colonies.
As you have noted, it was a combination of factors (including a failure of appropriate adaptation) which caused the collapse. I used the word "geopolitical" as an umbrella term for the various events: an increasing southward push by the Inuit; taxational pressure from Copenhagen; increased competition from Russian suppliers of walrus ivory & renewed elephant ivory supplies from Africa. Including a societal change in Europe ~ there was a gradual fall-off in demand for ivory as a luxury good.
Like the average plane crash: a number of adverse circumstances came together.
The climate Take-Home Message is that the decline of the MWP was too trivial a matter to finish off the Greenland Vikings.
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TVC15 at 08:37 AM on 26 September 2019Climate's changed before
Thank you both so very much!
I shared the information that you both offered and a snarky denier came back as spouted off this at me.
Nothing is unprecedented. Try science.The science is settled:Palaeo data suggest that Greenland must have been largely ice free during Marine Isotope Stage 11 (MIS-11). The globally averaged MIS-11 sea level is estimated to have reached between 6–13 m above that of today.
[emphasis mine]
https://www.nature.com/articles/ncomms16008
“Even though the warm Eemian period was a period when the oceans were four to eight meters higher than today, the ice sheet in northwest Greenland was only a few hundred meters lower than the current level, which indicates that the contribution from the Greenland ice sheet was less than half the total sea-level rise during that period,” says Dorthe Dahl-Jensen, Professor at the Niels Bohr Institute, University of Copenhagen, and leader of the NEEM-project.
[emphasis mine]
https://www.nbi.ku.dk/english/news/n...e-of-the-past/
The sea levels are going to rise and you can't stop it, so stop pretending you can.
What the heck can I make of this denier's snarky reponse?
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Climate denier scientists think these 5 arguments will persuade EU and UN leaders
Impressive letter coming from 500 "scientists"! There are 14 "ambassadors" signing the letter so let's have a look. Richard Lindzen? OK, he's a scientist though of course one that has been wrong repeatedly. Now HERE's a name that stands out; "The Viscount Monckton of Brenchley, United Kingdom". Yes indeed, the bug-eyed man who is literally nuts is one of their "ambassadors." That's more than enough for me to dismiss the entire thing without even attempting an analysis.
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michael sweet at 05:00 AM on 26 September 2019CO2 effect is saturated
Pringlesx,
It seems to me that your analogy fails becasue you used way too many sleeping bags. (100 bags with doubling CO2 equal to the hundredth bag).
A better analogy would be one sleeping bag with doubling CO2 equal to another bag.
You also use a base concentration of CO2 as 400 ppm. The pre-industrial revolution concentration of CO2 was 270 ppm so it will be doubled at 540 ppm and not 800 ppm as you stated.
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PringlesX at 04:48 AM on 26 September 2019CO2 effect is saturated
It seems like i wasnt alone to make that analogy.
If possible, please change the scenario in any way you like, that explains what you believe is happening during a CO2 increase.
https://www.acs.org/content/acs/en/climatescience/climatesciencenarratives/a-greenhouse-effect-analogy.htmlhttps://skepticalscience.com/SkS_Analogy_09_Greenhouse_effect_stack_of_blankets.html
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michael sweet at 04:43 AM on 26 September 2019CO2 effect is saturated
Bob,
Your link to Eli Rabbit was very informative. I had not previously seen data on how many collisions are needed to relax a CO2 molecule. Previous discussions I have seen suggested 5-10 collisions. Eli Rabbit provided data showing 105 collisions were needed!! That meant that there are only about 100,000 relaxing collisions before the average time of emission and not many millions as I posted above. The rate is a little lower at the escape altitude because it is colder and the concentration of molecules is lower.
The point that most excited CO2 molecules relax and distribute their energy to nearby molecules and do not re-emit the photon still stands.
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PringlesX at 04:42 AM on 26 September 2019CO2 effect is saturated
The hole tread starts with an even simpler analogy of a water tank with pipes used to try to debunk the saturation effect.
With little googling, i found my analogy is used elsewhere, so it seems i wasnt that far out anyway. (see links)
So i am interested if its possible to debunk the saturation effect by setting up the scenario in the more correct way.
https://www.acs.org/content/acs/en/climatescience/climatesciencenarratives/a-greenhouse-effect-analogy.html
https://skepticalscience.com/SkS_Analogy_09_Greenhouse_effect_stack_of_blankets.html -
Was Greenland really green in the past?
Part II...
4) As for Norse relations with the Inuit, we have the Inuits' recollections (see Rink's Tales and Traditions of the Eskimo). The Inuit themselves paint a mixed picture of relations with the Norse, sometimes friendly, sometimes hostile. It probably varied from tribe to tribe and time to time. They certainly didn't think of the Norse as maladapted. Diamond also mischaracterizes a case of an Inuit, who was found mortally wounded after a raid on a Norse settlement, as the victim of some Mengele-like medical experiment (see Gad).
As for why the Norse settlement failed, the arrival of the Little Ice Age didn't help, nor did occasional fighting with the Inuit (and possibly the Basque), but there were other factors. The Norwegian government placed high taxes on trade with Greenland, and required visiting traders to buy Greenlandic goods, which hardly helped. The biggest factor was the competition for walrus ivory with elephant ivory during the 14th Century. Greenland simply went bust, like many a boom economy.
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Was Greenland really green in the past?
Daniel Bailey:
"If you want further proof and readings about what the Viking settlements failed, read Jared Diamond's "Collapse"…"
...and Eclectic:
"In the Greenland section of Jared Diamond's book "Collapse", he describes the Norse settlements in Greenland as failing owing to cultural factors rather than climate.
The rise & spread of Muslim power (in Africa and the Middle East) blocked or impeded the European import of elephant ivory. Consequently the Norse Greenlanders initially became quite wealthy by harvesting and exporting walrus ivory to Western Europe. But that trade later altered as "geopolitics" changed.
Some aspects of Norse farming methodology were not well suited to Greenland conditions, and there was necessarily a swing to more reliance on wildlife hunting and especially the harvesting of seals.
The Norse despised the aboriginal Inuit as heathen & uncivilized. Intermarriage with Inuit and prudent diplomatic relations with Inuit did not happen. The reverse — there were increasing hostilities with the Inuit, skirmishes and even some pitched battles (casualty numbers small but of course higly significant for such a small population of Norse. *IIRC*, Diamond equated the Norse warriors lost in the worst battle, as representing the U.S. Army losing 3 million men in a single battle).
In short, the Norse failed to live with their Inuit neighbours and failed to make full use of the "technology" which had sustained the Inuit in Greenland over thousands of years. A lesson for us all..."
Using Daiamond's Collapse is problematic.
1) Diamond's argument (actually, McGovern's, see "The Fate of Greenland's Vikings", Archaeology) that the Norse should have adopted the toggle harpoon for ring seal hunting ignores that fact that even the Inuit (Eskimos) couldn't make them work for coastal fishing during this time, since the ice wasn't thick enough (see Gad, History of Greenland, Vol. I, p. 166).
2) Diamond's (and McGovern's) claim that Greenland Norse didn't fish is ridiculous. When asked by a journalist, the archaeologist Jette Arneborg literally laughed (see Brown, The Far Traveler, 153). If Diamond had properly studied the Farm Beneath the Sands study, he would have realized that the reason so few fish bones were found is that they are very fragile, so the archaeologists weren't even looking for them at first. Once they started, despite the inherent difficulty, they found them (Enghoff, 7, 19, 48, 88). They also ignore Greenland Norse fishing gear, and the Norse accounts of fishing.
3) Diamond claims that the Norse over-forested and -grazed Greenland. Georg Nyegaard studied a Norse farm, and found it had minimal effect (see his talk with Brown in The Far Traveller, 159-160). It certainly wasn't bad enough to drive the Norse to starvation. Even Diamond admits that there is evidence for only one Greenland Norseman who may possibly have starved to death (Collapse, 267), even as he describes the easily found evidence for entire families of the supposedly well adapted Inuit starving to death in their igloos (264, 273). Apparently, the guys who weren't starving to death in droves were supposed to take tips from the guys who were.
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Mal Adapted at 02:33 AM on 26 September 2019Using fallacy cartoons in a quiz
Fun quiz. I got 14/15 correct 8^}. Do I have to be a Twitter user to find out the aggregated results?
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Bob Loblaw at 01:45 AM on 26 September 2019CO2 effect is saturated
PringlesX @ 548:
You say you "found a [sic] interesting site from chicago university that simulates the band saturation."???
How did you find it? That is the exact link I gave you in comment #540. You are reading the comments people make in response to your posts, aren't you?
Now, given that you have provided a series of graphs from that model "that simulates the band saturation", can you please provide us with an explanation of:
- exactly what in those diagrams "shows" what you claim is "saturation"? and
- exactly what the significance of that "saturation" is, with respect to CO2 and the greenhouse effect?
Right now, it looks like you are just throwing stuff at the wall hoping something sticks.
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Bob Loblaw at 01:35 AM on 26 September 2019CO2 effect is saturated
GwbS@542:
Please do not make strawman arguments. I explicitly said that the diagram in comment 529 applies to the absorption ONLY of radiation, and that I have not considered emission. In comment 534 I give a list of other factors that must be considered. #3 is the mission of radiation. You do yourself no favours by arguing against a position that I have explicitly addressed as incomplete. When ONLY considering absorption, the decay is indeed exponential, and when considering the probabilty of a surface-emitted photon reaching space in one step, absorption is the only relevant factor. Photons emitted in the atmopshere above the surface are - by definition - not emitted from the surface..
You also refer to "reflected" IR radiation. IR radiation is not reflected. Reflection results in photons travelling in a different direction, but remaining at the same wavelength/frequency as they were before reflection. IR radiation is first absorbed, then re-emitted. The emission, as others have stated, is not dependent on the wavelength of the radiation that was absorbed - it depends on the temperature and characteristics of the molecule that is doing the emitting.This may be another CO2 molecule, but it may also be another greenhouse gas. It almost certainly won't be the exact same molecule that did the absorbing. This distinction between "reflection" and "absorption/re-emission" is critical in understanding atmospheric radiation transfer, and you do yourself no favours by conflating the two.
In 547, you state "They may be absorbed, but are emitted again within a fraction of a second". This is basically true, but the amount of time it takes a CO2 molecule to lose the energy by collision is a lot shorter than a "fraction of a second". Eli Rabett has done the math for us:
http://rabett.blogspot.com/2013/04/this-is-where-eli-came-in.html
The time estimate between collisions is 10 us. A CO2 molecule that absorbs IR radiation almost always loses it to other molecules via collision. CO2 molecules that emit IR radiation are almost alwys getting that energy from other collisions.
You also state "the fraction exiting at the top is inversely proportional to the length of the column (or the density)." Physical measurements in units of distance are irrelevant. What matters is the number of particles/molecules/etc. along a path. This varies with altitude depending on the local absolute concentration (not ppm, but molecules/unit volume).
Proper radiation calculations take this into effect.
I repeat what I said in post 534: "The only "saturation" that occurs is for useless and innacurate descriptions of the process." That specific wavelengths show zero direct tranmission of radiation from the surface to space is not an argument against the effects of increasing atmospheric CO2.
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Ebel at 00:14 AM on 26 September 2019The Consensus Handbook: download and translations
Im Fazit des Handbuchs steht "mit Zahlenbelegen". Das erscheint mir zu wenig. Es sollte ein kurzer Abriß der Zusammenhänge gebracht werden. Stichworte: Änderung der Tropopausenhöhe, Schwarzschild.
In the conclusion (p. 21) of the manual it says "clear numeric terms". That seems too little to me. A short outline of the connections should be brought. Keywords: Change of the tropopause height, Schwarzschild 1906.
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richieb1234 at 20:34 PM on 25 September 20192019 SkS Weekly Climate Change & Global Warming Digest #38
Moderator
Thanks. I will try that.
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michael sweet at 11:50 AM on 25 September 20192019 SkS Weekly Climate Change & Global Warming Digest #38
Ritchieb,
Unfortunately, I am a dinosaur at extracting images.
I am doing well. I have moved off grid onto a sailboat and will be out of the country until December. I will infrequently post untill I am back.
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AlexDeBastiat at 11:36 AM on 25 September 2019We're heading into an ice age
Thanks for your posts. I'm starting to see your points on this.
In the past, the orbital cycle must've had enough effect to start a feedback loop to begin the glaciation cycle. As the ice sheets grew, it reflected more and more solar energy. At the same time, carbon based life increasingly died off due to the temperature change, trapping CO2 on earth. When the orbital cycle reversed, all of this CO2 was released back into the atmosphere again through its own feedback loop (life begetting more and more CO2). This warming feedback loop is also proof that CO2 plays a very large role in warming as there is no other reason to explain how the temperature could spike so much during the interglaciations.
Now in the last 150 yrs or so...Humans have created a new mechanism which allows for a substantial amount of pre holocene CO2 (which was trapped deep under the ground) to be emitted back into the atmosphere....and this likely has altered the normal feedback loops we have seen in the data for the holocene.
Since there is so much CO2 in the atmosphere now, these cycles may now likely be broken and meaningless as our CO2 concentration are out of the norm for the holocene. This makes sense to me given that we are using CO2 from periods(jurassic, etc.) where temperatures were much hotter then the holocene.
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richieb1234 at 11:13 AM on 25 September 20192019 SkS Weekly Climate Change & Global Warming Digest #38
Michael Sweet
How are you? Nice to hear from you again. I have the PDF, but I cannot extract the images. I was hoping someone knew where to find them at another location.
Moderator Response:[PS] Try here for suggestions on extracting images. Many images in that report are sourced from elsewhere so you could larger version by going to source.
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michael sweet at 10:59 AM on 25 September 2019CO2 effect is saturated
GwsB,
At 547 you said:
"It is based on the idea that photons don't just disappear. They may be absorbed, but are emitted again within a fraction of a second. So I have problems with the first paragraph of post 546 by Michael Sweet which seem to suggest that there is no conservation of photons." my emphasis
This is incorrect. The CO2 molecule has many collisions (millions or higher) with other molecules before it can emit a new photon. The collisions convert the photon's energy into heat in the surrounding molecules.
As soon as a photon is absorbed by a CO2 molecule, the energy of the photon is converted into vibrational energy in the molecule and the photon no longer exists. The collision rate is many orders of magnitude faster than the emission rate so the energy is distributed by collisions to other molecules in the air. Other CO2 molecules, that are boosted into the excited state by molecular collisions, emit photons that effectively replace the original photon.
This is the primary mode of heat transfer in the atmosphere so it cannot be considered negligible.
It is my understanding that little heat is "reflected" back. Energy is absorbed by a layer of the atmosphere. Then new photons are emitted, both up and down, according to the temperature of the layer as described by the Boltzmann equation.
It seems to me that you are trying to model a system you do not understand well. I recommend you read what specialists in the field say to learn faster how the greenhouse effect works.
The emission altitude (about 10,000 meters) is the key point for the greenhouse effect. Here the atmospheric pressure is only about 25 kPa, 1/4 sea level pressure, and the temperature is -50C. The cold freezes out water (vapor pressure of .0039 kPa versus 1.2 kPa at 10C) and the effective CO2 concentration is 1/4 sea level concentration. Saturation is not an issue at 10,000 meters, nor is overlap of water bands. Discussing saturation at the Earth's surface is incorrect.
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michael sweet at 10:09 AM on 25 September 20192019 SkS Weekly Climate Change & Global Warming Digest #38
Richieb,
GOOGLE suggests a PDF of the report is here
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michael sweet at 09:50 AM on 25 September 2019CO2 effect is saturated
Pringlesx:
You raise an interesting question. Fortunately, the answer can be easily calculated.
According to this web site, insulation r values add. I am a cheap SOB so I buy cheap R=1 m2 T/W sleeping bags (metric units). Since I have 99 cheap sleeping bags the total R value is 99 m2 T/W.
To calculate the internal temperature we use the equation:
Watts = m2 x deltaT devided by R
My sleeping bags are 2 meters long and 2 meters around so they have a surface area of 4 meters square. A human body generates about 100 watts of energy while sleeping.
Plugging the data into the equation I find the temperature difference after you stay in the bags to equilibrium is 100W x 99R devided by 4 = about 2475 degrees C. If it is -50C outside than the center of the bag is 2425C. That is hot enough to melt steel!! If you add a cotton layer it would have little effect on the temperature (R<<1), but you would be dead after a night in your 100 sleeping bags. If I buy better quality R=2 sleeping bags it will be 5,000C at equilibrium.
We will all be dead if we follow your advice to do nothing about Global Warming.
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scaddenp at 08:05 AM on 25 September 2019CO2 effect is saturated
Well if you want to push the sleeping bag analogy, increasing the insulation strength will always increase the temperature (Fourier Law). However, you cannot push the analogy too far. The key to understanding the saturation argument is undertstanding the importance of the temperature profile to absorption. The Modtran outputs you posted looked fine so I only assume you are not understanding how they work. Try this discussion.
Ultimately though, it is great to try and understand the impact of the equations, but it is unreasonable to deny the lab and field tested solutions. When you can directly measure the increase in radiation from added CO2, then obviously the effect is not saturated.
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scaddenp at 06:56 AM on 25 September 2019We're heading into an ice age
"Secondly, there is no hard data offered in this argument to show why the tilt and orbit are weak for this time period."
I am not I following this. The astronomical cycles are very strongly established by observation (look up Milankovitch cycles or see the animations here). The effects on irradiation of the surface were calculated by hand by Milankovich (while in jail from memory) and have been repeated and checked numerous times.
An analysis of the current glacial cycle is in Berger 2002 but rather moot given our CO2 levels. Remember that Milankovich cycles have been around for a long time, but can only induce glaciation when CO2 levels drop to level where summer snows dont melt at around 65N during low irradiation. The last time we had 400ppm was pliocene and there was no glacial cycle.
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Eclectic at 05:26 AM on 25 September 2019CO2 effect is saturated
PringlesX ,
sorry, but your "sleeping bag" analogy simply doesn't fit the situation.
And there seems to be no connection between Greenhouse and the "hockey stick".
Since the Hockey Stick has been well validated by a number of subsequent scientific studies (even without tree-ring data) . . . then it sounds like "Manhattancontrarian" is probably just one of those many clickbait blogsites. You know ~ one of those clickbait sites with stuff like "Scientists prove Earth is flat" . . . "Infrared photos show English Queen is a Lizardperson" . . . "Russian lasers show Moon is green cheese" . . . and so on.
Really, PringlesX, if Mr Manhattancontrarian has some astounding new earth-shattering information on The Hockey Stick (info is which strangely unreported by the world's media) ~ then please, please give us readers a succinct summary of it. On the appropriate SkS thread, of course. Let's not go down the brainless clickbait path !
Moderator Response:[PS] Please refraim from discussing "hockey stick" on this topic. Discussions of that belong here.
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richieb1234 at 05:16 AM on 25 September 20192019 SkS Weekly Climate Change & Global Warming Digest #38
The report "Global Climate 2015-2019" has a number of very useful graphs and other images. Does anyone know how I can get electronic copies of them?
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PringlesX at 03:45 AM on 25 September 2019CO2 effect is saturated
We seem to agree on that the effect lays in the TOA and the transmission curve at high altitudes.
So, just for fun, is it possible to explain the argumented athmospheric big effect with some analogy? :-)
If i am outside in antartica in 100 layers of sleeping bags. But the most outer sleeping bag is only a cotton layer so it radiates a lot from this layer at all its internal altitudes with the wind blowing though it etc.
Double the amount of CO2 to 800ppm corresponds to exchanging that 100th cotton layer into a regular sleeping bag. So now the transmission curve has changed drastically of the top layer.
But i was already in 99 nice sleeping bags. Could you alter the effect in this scenario that corresponds to what you believe is actually happening? -
PringlesX at 03:13 AM on 25 September 2019CO2 effect is saturated
Many of those spectrum in previous comments, is not showing the whole infrared transmission spectrum below 400 1/cm. Why? It seems be manipulative if there isnt good reason for it.
Anyway, I found a interesting site from chicago university that simulates the band saturation.
http://climatemodels.uchicago.edu/modtran/
(The site used in the following video:)
https://www.youtube.com/watch?v=ZMgNYDtueKQModerator Response:[DB] Please limit image widths to 450. Subsequent violations will be removed.
Inflammatory snipped.
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Daniel Bailey at 00:57 AM on 25 September 2019Climate's changed before
In the spirit of transparency and full context, the basins of the Great Lakes are the product of repeated and successive glaciations, and not just the most recent. From Larson and Schaetzl, 2001:
"The basins that contain the Great Lakes are the product of repeated scour and erosion of relatively weak bedrock by continental glaciers that advanced into the Great Lakes watershed beginning perhaps as early as 2.4 Ma. Most of the scouring, however, probably occurred after about 0.78 Ma when episodic glaciation of North America was much more extensive, with ice cover sometimes extending as far south as Kentucky."
A full perusal of this fine document reveals that the southern lobes of the Great Lakes were ice-free at the near peak of the Last Glacial Maximum at 25,000 years BP and that the most southern advance of the ice during the last glacial phase occurred well after the LGM and during the deglaciation phase of the Laurentide Ice Sheet, when cold (dry) ice processes had shifted over to wet processes (promoting ice flow). From Figure 8:
Full copy available here.
The point is, it's pretty easy to show the interested onlooker just how uneducated your particular pretend-skeptic actually is by doing some digging. The plus side to all that digging is in the self-learning you accomplish.
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Daniel Bailey at 00:36 AM on 25 September 2019Climate's changed before
"Alaskan Glaciers started receding big time around 1750 to 1900"
As opposed to those promoting misinformation, looking at the full context of the Holocene, Alaska glaciers have only been recently declining, reversing a 8,000 year period of growth and expansion:
Per McKay et al 2018 - The Onset and Rate of Holocene Neoglacial Cooling in the Arctic
"Arctic summer temperatures have decreased for the past 8,000 years, before rapidly warming over the past century. As temperatures cooled, glaciers that had melted began to regrow throughout the Arctic, a phenomenon and a time interval known as Neoglaciation.
This study seeks to understand the nature of this cooling and whether or not this indicates a tipping point in the climate system. Specifically, we use a large database of records from ice cores, lakes, ocean sediment, and more paleoclimate archives to detect patterns of cooling. We investigate these patterns, and climate model simulations, to determine what parts of the Arctic experienced Neoglaciation at the same time, how rapidly it cooled, and what climate models indicate about the causes of cooling.
We find that the Arctic did not cool simultaneously, but different regions cooled at different times and that the climate models perform well when simulating both the timing and amount of Arctic cooling."
Full copy available here.
Further, recent climate warming in the central Yukon region has surpassed the warmest temperatures experienced in the previous 13,600 years (and therefore likely the past 100,000 years).
Porter et al 2019 - Recent summer warming in northwestern Canada exceeds the Holocene thermal maximum
News release here.
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Eclectic at 00:18 AM on 25 September 2019We're heading into an ice age
AlexDeBastiat @395 ,
Of the glaciation/deglaciation cycles of the last million years, each cycle has been unique in structure, because the precise relations of orbital eccentricity and planetary tilt have been subtly different.
So every cycle has been an "N of 1" . Yet the paleo evidence shows that these climate variations have nevertheless operated within narrow limits of conformation. And from those past cases we know that the present Interglacial would "naturally" last something upwards of 25,000 years without the human intervention which has now occurred. ( It is perhaps rather too early to say whether the current high levels of CO2 will cause a complete "skip" of the next scheduled glaciation. )
Alex , if you have some definite contrary evidence (i.e. a scientific paper in a respected journal) then please cite it.
Alex , your third paragraph is rather jumbled in its ideas. Could you please clarify what you mean?
On your fourth paragraph: I would be interested to hear whether (and how ) you would compare the dangers to humanity from the present-century very rapid global warming . . . compared with the dangers to humanity from a very slow ( 10,000 to 20,000+ years' duration ) of global cooling. [Though this cooling scenario has now become abstract & hypothetical.]
Basically, I am thinking that 10,000+ years is plenty of time for the human race to find technological solutions in dealing with such cooling . . . or perhaps even to revert to low-tech methods such as the well-proven anti-cooling technique involving burning a small number of gigatons of coal !
On the other hand: for dealing with the immediate & very pressing problems of rapid global warming during the next 50+ years ~ our politicians seem paralysed like rabbits in a spotlight.
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GwsB at 23:47 PM on 24 September 2019CO2 effect is saturated
Thank you MA Rodger for posting the figures in Zhong and Haigh (2013). Would it be possible to print 6(c) separately in a post so one can read the explanation inside the figure.
The black line in Fig 6(c) which is horizontal to the right of 10**2 shows the instantaneous relative forcing due to the central interval of the CO2 absorption 650-680/cm, which is 15 μm plusminus 2%. At the present level of 400 ppmv there is saturation. Fig 2 in Zhong and Haigh (2013) shows that 650-680 is the peak of the absorption coefficient for CO2 between 500 and 1500/cm. The absorption coefficient in the central interval lies between 100 and 1000. In the shoulders the absorption coefficient lies between 1 and 100 and in the wings it is less than one. This is a rough impression. Figure 2 is not very detailed. The statement: "At wavelength 15 mm there is saturation" is true. The statement: "The contribution of the shoulders compared to the central region around 15 μm is negligible" is also true if one looks carefully at Figure 2. It is only by looking better at Figure 6(c) that one sees that the shoulders 590-650/cm and 680-750/cm do make a significant contribution and that saturation at these wavelengths is still far off (it will occur at 40 000 ppmv).
Zhong and Haigh (2013) have used the latest version HITRAN2008 for the analysis which underlies their paper. It is possible that older versions give different results for which the absorption of the shoulders is weaker. The notion of saturation is based on the iconic figure in Wikipedia https://en.wikipedia.org/wiki/Greenhouse_effect which was removed from my post 525 since it was too large. Saturation is a serious objection and it takes a lot of work (see Zhong and Haigh (2013)) to counter it.
The post 542 tries to get at the basics of "absorption" or "reflection" for long wave radiation at around 15 mm. The model I describe is a basic description in terms of photons. Since I am a mathematician specialized in probability theory it seems quite natural to me to use a random walk. I was surprised to see how well it fits with Figure 6(c) in Haigh and Zhong (2013) where one looks at narrow bands of wavelengths. The logarithmic increase shown in Figure 6(b) between 50 and 5000 is a fluke. It is meaningless. It is the result of adding a constant function, two concave functions and three convex functions in Figure 6(c).
The basic description in terms of reflection in post 542 does not take secondary effects like temperature differences in the troposphere into account. It is based on the idea that photons don't just disappear. They may be absorbed, but are emitted again within a fraction of a second. So I have problems with the first paragraph of post 546 by Michael Sweet which seem to suggest that there is no conservation of photons.
My understanding is that the amount of heat (energy) due to the vibration caused by the absorption of photons at around 15 mm is negligible, and that it is the long wave radiation reflected back to earth as described in the random walk model which is the "greenhouse effect".
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AlexDeBastiat at 21:40 PM on 24 September 2019We're heading into an ice age
This answer is not adequate, and this is the one aspect of climate change that I can't get past. You are not using enough hard scientific facts to support your position.
Firstly, you say there was a similar condition as ours over 400,000 years ago that had a warming period of 30,000 years, but it is an N of 1. How can we rely on just one instance of data? I feel like this singular piece of data cannot be used as support for this argument.
Secondly, there is no hard data offered in this argument to show why the tilt and orbit are weak for this time period. When you are talking about thousands of years, the timing may be off by a couple decades. Just because you don't see things happening don't mean that they will not happen. This is a common falacy people have. Possibly the scientific community is measuring the wrong things? We should be looking at leading indicators of ice age activity.
Thirdly, there is also no discussion about the benfits of C02 which if it is stalling an ice age has likely helped save billions of lives as a new ice age would be catastrophic. Possibly there is a necessity for some C02 emission to prevent an ice age from forming.
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MA Rodger at 18:31 PM on 24 September 2019Climate's changed before
TVC15 @776,
The denialist asks about the features of two different times and asks what is different today.
20,000 years ago was the maximum glaciation of the last ice age, this the result of reduced solar radiation for the high-latitude Northern summers which 100,000 years ago triggered an increase in the amount of ice-covered land/ocean in high Northern latitudes. The level of ice was amplified by the increased albedo of the ice reflecting away greater levels of solar radiation and by the reduced GHGs (CO2 & methane) caused by the cooling global climate having a net draw-down of such gases. Thus we find the Laurentide & Cordilleran ice sheets covering mainly Canada and beyond, extending to cover the sites of today's Great Lakes. (The map below ignores changing coast lines.) It thus requires the Laurentide Ice Sheet to melt considerably before the Great Lakes can exist, their formation reportedly beginning 14,000 years ago.
We now leap forward to a time when the Cordilleran ice sheet has long gone. Over recent times the dynamics of glaciers is not always determined by local temperature. A sea-terminating glacier will likely spend most of its days slowing advancing and then, becoming unstable, undergo a short period of rapid retreat. And reduced/increased snowfall can cause a glacier to shrink/expand.
So is there evidence that "Alaskan Glaciers started receding big time around 1750 to 1900"? Solomina et al (2016) who, in an analysis of global glaciers over the last two millenia, examine land-terminated glaciers in Alaska and see no sign of it. Their Fig 2 shows a GEI index indicating a fluctuation in local glacier size which peaked at about 1880AD. This would explain a "receding big time around ... 1900" but not the earlier 1750 date. Other research may give differing timings but it seems unlikely that there is any proper support for a 1750 to 1900 date. Can the denialist provide support for this bold assertion of his?
And "why is now any different"? The unprecidented global rise in temperatures will impact glaciers globally, including Alaska.
Moderator Response:[DB] Fixed image display issue
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Eclectic at 16:46 PM on 24 September 2019Medieval Warm Period was warmer
JP1980 @265 ,
as Scaddenp (@266) indicates, there is much that is wrong with KalteSonne's blog article.
In the first paragraph, the blog asserts that the MWP was hotter (or "similar") in temperature to today. Which is false. Various types of proxy temperature measurements show that the Medieval Warm Period was cooler than today's global climate. In addition, the land ice-shelves and glaciers were larger than today's, and the mean sea level was lower than today's. All these three types of evidence demonstrate the warmth of today and the relative coolness of the MWP.
KalteSonne is indulging in wishful thinking — not scientific thinking. Having made such a blunder to start with, it is not surprising to find that there are subsequent errors.
In the second paragraph, he [presumably he] goes on to present a misleading picture by taking quotes out of context. He misrepresents the message of the IPCC. And he fails to understand that the MWP was such a slight deviation of average world temperature, that one would of course not expect it to show up in a "hindcast" of computational models based on 20th/21st Century climate. (Hence his attack on climatologists' models — an attack which seems to be his underlying purpose in discussing the MWP.)
A further failure of KalteSonne, is his failure to acknowledge (to himself and to his readers) that the current warming event is not only larger and definitely worldwide . . . and that it is greatly faster & has a continuing steep upward trajectory ~ all of which is distinctly different from the MWP.
Clearly, he fails to understand the mechanisms causing climate change.
In short: KalteSonne's ideas are nonsense.
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scaddenp at 14:49 PM on 24 September 2019Medieval Warm Period was warmer
Where to start. Firstly as MA Rodger was pointing out, it is misrepresenting what the science says by selective quoting. Secondly, it is playing with a strawman fallacy in the title - CO2 is not the only driver of warming and model reconstructions can reproduce the pattern of warming.
An important contrast with today's warming is the lack of synchronicity globally. The CO2 science project hides that by going for very long time period and some very dubious baselining. There are numerous peer-reviewed papers which recontruct both NH and global temperatures which take a rigorous approach to handling the proxies (See the AR4 and AR5 for the list and plots) but of course these dont get the "right answer" for denialists.
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JP1980 at 14:11 PM on 24 September 2019Medieval Warm Period was warmer
MA Rodger @264
Other than your comment about the truncation of the last paragraph of IPCC AR5 Section 5.3.5, do you have an actual complaint with the article's arguments?
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TVC15 at 11:32 AM on 24 September 20192009-2010 winter saw record cold spells
Thank you both @19 scaddenp and @20 MA Rodger!
I found this graph as well that shows temps only rising in NY.
What I've learned in debating climate change deniers is that science deniers won't be convinced by evidence because their views are not based on a rational way of responding to evidence in the first place.
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TVC15 at 10:10 AM on 24 September 2019Climate's changed before
A question from a denier.
The Northern Part of the US was covered in Ice 20,000 years ago and the Great lakes were only formed 10-14,000 years ago.
Alaskan Glaciers started receding big time around 1750 to 1900.
What caused all of that and why is now any different ?
All insights are welcome. :)
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michael sweet at 02:12 AM on 24 September 2019CO2 effect is saturated
GwsB,
It may be the problem with your model is that the number of photons emitted from one layer is not related to the number of photons it receives from other layers. The number of photons emitted is determined solely by the temperature of the layer.
Esentially all of the photonic energy received is immediately turned into heat. Then photons are emitted according to the Boseman relationship (t to the fourth power). Higher layers emit less photons per m2 than lower layers because they are colder. Your model ignores the temperature differences. A single photon does not random walk to outer space. A modeled walk at light speed does not account for the time spent as heat.
When higher layers absorb more photons coming up (because the CO2 concentration is higher due to man made CO2) the escape altitude increases. The temperature is lower at the new escape altitude because the atmosphere cools as you go higher (at the lapse rate). This causes an energy imbalance because less energy is emitted at the cooler altitude according to the Bozeman relationship. The new altitude has to warm to return to energy balance. This warming is transmitted down according to the lapse rate and results in surface heating.
At the escape altitude the CO2 absorbtion bands are not saturated so increasing CO2 increases absorbtion. Water is essentially not present so overlap of bands with water does not count either. The escape altitude increasing is the key to understanding the greenhouse effect. The lapse rate is 6C per kilometer. The escape altitude is about 10,000 meters. If the escape altitude increases 100 meters the surface temperature increases 0.6C.
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