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Comments 9301 to 9350:
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TVC15 at 15:31 PM on 29 September 2019Climate's changed before
MA Rodger @ 788
Thank you so much!!!!!
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ERRATA at 12:29 PM on 29 September 2019There is no consensus
Hi all!
First of all, thanks for this magnificent website, lots of interesting material and comments, but still a lot left to read and learn.
Please, allow me to quickly introduce myself, I live in a place around 66 degrees north and I'd refer to myself as "sceptic", rather than "denier", although I've been labeled in many different ways just because of a different opinion. I would consider myself as some sort of "environmentalist" since I am aware of the planet I live since my young ages and I took care of my actions to preserve my environment as much as possible. Today, I work for a company closely related to environmentalism and I'm trying to teach my child to be aware of our planet, however, in a very different way than other kids of his age are doing every Friday on the street. I am not a scientist of any sort, but I do consider myself fairly smart, especially because I'm in love with scientific method of "question everything" since the same young age, and this is the reason I consider myself a sceptic nowadays, not only when the issue of climate change is in question.
The same "question everything" method inspired me to register here and ask few questions. I hope that people here are more reasonable and doesn't look at other people's questions as some kind of trolling tactics, as it is happening more and more often in "social media" places. All my questions will be honest and without no bad intentions. They might be silly and "ignorant", but hey, I joined here to learn something new, so apologies in advance for any stupidity coming from my mouth :) Honestly, I am very confused at this point regarding climate discussion because of constant opposing statements, studies, conclusions, I hope I'll get some clarifications here.
Now, in past 2-3 days, I'm reading a lot around here, especially "Climate Myths" section and all the comments around. Seems like there's lots of smart people here with lots of knowledge about the topic, but what I didn't see often (actually probably never) is someone who would leave an impression of "questioning everything". Why is that so? Especially if someone presents material from contrarian scientists which is trying to "question" the opposing statements. It looks to me like one side is not quite ready to have a debate, while the other one is desperate for it and to send a message which is constantly being silenced. This kind of behaviour is moving me away more and more from my currently shaky belief in climate change, no matter how crazy that sounds.
I am very happy that I came across this website because it started to bring back some logical conclusions in my mind, but then, just today, I noticed 2 articles which again started forcing me not to take anything written here for granted.
To make it more interesting, one of the articles is from Myles Allen himself. It's not that he is denying anything, but he is somewhat confirming that lots of people got some things wrong and jumped to wrong conclusions (https://theconversation.com/why-protesters-should-be-wary-of-12-years-to-climate-breakdown-rhetoric-115489). The other article talks about my other point about the debate, and it really sounds to me like lots of other scientists are silenced and no one cares about their opinion. How in the world is that possible in the "science" in the first place? (https://climatechangedispatch.com/500-scientists-no-climate-emergency/). So, I assume that my other question would be, what are your opinios on those 2 articles?
Thanks for your time and for all the answers!
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Dimiter at 07:58 AM on 29 September 2019Water vapor is the most powerful greenhouse gas
Please update the link to the article from Santer 2007 --> https://www.pnas.org/content/pnas/104/39/15248.full.pdf
Moderator Response:[PS] Thanks very much for that. I have updated the Held 2000 link in the rebuttal as well.
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MA Rodger at 18:33 PM on 28 September 2019Climate's changed before
TVC15 @787,
This graphic has already appeared up-thread and is snatched from the web but originates from this webpage. (You need to click the top-left icon to get the 800,000 year version.) The underlying study is Spratt & Lisiecki (2015).
If your denier who is "trying to say that Milankovitch Cycles are irrelevant" actually manages to achieve such an assertion, perhaps he should be asked what would trigger ice ages if not milankovitch cycles?
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Eclectic at 18:19 PM on 28 September 2019There is no consensus
JBeez , please also edit/correct: "exacerbated". If English is not your first language, then you can make a post in your Mother Tongue — but you may be slow to get replies. There are a few posters who make their post that way; but they are usually wise enough to make an English subscript, even if it comes across a bit clumsily (still, readers are tolerant enough to make the best of it).
If you wish to improve your knowledge of the relative efficacies of CO2 and H2O, then please make your post in an appropriate thread [not this thread].
Look at the upper left corner of this page :- "MOST USED Climate Myths" . . . and (from more than 100 threads) choose the best fit. You might care to select Myth 30 or Myth 36 , perhaps. Read the Basic (and more Advanced versions) and also look through the 100's of comments (some trashy, some very informative).
That will help you in getting up to speed, on the science of Greenhouse. Starting from your base position, you may well need rather more than that. But, it will be a good first step in understanding what the scientists are talking about.
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JBeez at 14:12 PM on 28 September 2019There is no consensus
*their, since i can't edit
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JBeez at 14:10 PM on 28 September 2019There is no consensus
Unfortunately, CO2's effects on weather are overly exacerbated by scientists who haven't taken the time to study the behavior of matter in depth with respect to radiation. Until they stop talking about CO2 being responsible and move the conversation to H20, they're consensus doesn't mean anything. Study the matter before you make assumptions. CO2 is a miniscule GG compared to H20 and there's not enough of it to make a comparison at this point.
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TVC15 at 10:04 AM on 28 September 2019Climate's changed before
MA Rodger @ 780
Where can I find easy to understand data that shows that only two of the last 8 eight had sea level rise higher than today?
Also a denier is trying to say that Milankovitch Cycles are irrelevant. Where do they get idea that from I wonder?
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nigelj at 06:50 AM on 28 September 2019CSLDF: Events at NOAA Highlight Strengths and Shortcomings of Agency Scientific Integrity Policies
More administration interference in good science: Clean-air scientists fired by EPA to reconvene in snub to Trump
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Bob Loblaw at 05:56 AM on 28 September 2019CO2 effect is saturated
What michael sweet said...
Also, pressure is simply the weight of all overlying gases. If air density were constant, air pressure would drop linearly with height. Air density isn't constant, because pressure drops with height. In the end, air pressure basically decreases logarithmically with height (to a first approximation).
https://en.wikipedia.org/wiki/Atmospheric_pressure
In atmospheric models, they often use pressure as the vertical coordinate. Layers spaced equally in pressure would be roughly equally-spaced on a log(height) scale, or logarithmcially-spaced on a linear height scale.
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vrooomie at 05:17 AM on 28 September 2019Using fallacy cartoons in a quiz
Well-done, as always!
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michael sweet at 04:19 AM on 28 September 2019CO2 effect is saturated
You are progressing a little.
Concentration is measured as Molarity which is moles per liter. Ppm is a fraction of particles of dry air and is not concentration . For gases, molarity is directly proportional to pressure. This varies with height. Sometime pressure is used for concentration.
It is a waste of time to attempt to model systems you do not understand. The system is not saturated.
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GwsB at 01:14 AM on 28 September 2019CO2 effect is saturated
The model in 542 is wrong I have to admit. It is wrong for two reasons:
1) My impression was that vibrational energy and the kinetic energy mv2/2 were systems with little interaction. That is not the case. Michael Sweet in post 553 and Bob Loblaw in post 554 correct me here. Here is another reference (which gives a proportion of 10**9 instead of 10**5)
https://sealevel.info/Happer_UNC_2014-09-08/Another_question.htmlSo in the new model the photon at a wavelength of 15 μm travels an average of 25 m before being absorbed by a CO2 molecule which goes into a vibrational state, and which then collides (whatever that means (distance between the centers of the molecules less than the minimum of the two radii?)) with a Nitrogen or Oxygen molecule and falls back into the zero vibrational state (why?) and transfers the vibrational energy into kinetic energy over the two molecules. So CO2 transforms the energy of photons of certain wavelengths into kinetic energy of the atmosphere close (around 25 m) to the position where the photon was emitted.
2) According to Fig 1 in Zhong & Haigh (2013) of the 239 W/m2 outgoing longwave radiation only 22 W/m2 comes directly from the earth. This is from Trenberth & Fasullo (2012). In Tremberth, Fasullo & Kiehl (2009) it is still 40 W/m2.
Looking down from outer space for each photon leaving the earth system at TOA (which is 100 km above the surface according to Google. Is that correct?) one should be able to specify its wavelength and the level above the earth surface where it originated. Around 9% originate at the surface. It would seem that 90% originates close to the surface, say less than 1 or 2 km, except for the wavelengths around 15 mm, which originate at 10 km. (In figure 4 in Zhong and Haigh (2013) the red line follows the Boltzmann-curve for 290K rather than 260K, see figure 3, the temperature at 5 km).
The saturation of CO2 for certain wavelengths shown in the black blue and green graphs in Figure 6(c) in Zhong & Haigh (2013) suggest a transmission which decreases like the inverse of the concentration of CO2 as it approaches the limit value. That agrees with the model in post 542 but I do not see how the new model will give this result.
I think concentration (ppm) is the variable of interest, not density (parts per m3). The twenty layers of my original model each contain the same amount of matter. Their height may vary. The effective CO2 concentration at 10 or 20 km is the same as at sea level. See for instance Aoki et al. (2003) Carbon dioxide variations in the stratosphere over Japan, Scandinavia and Antarctica. Tellus (2003) 55B, 178--186. CO2 is 50% heavier than oxygen or nitrogen, so one would expect it to settle down at the bottom. If it did it would form a layer of pure CO2 more than three meters high. A hundred years ago that was only a bit more than two meters!
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Estoma at 21:32 PM on 27 September 2019Climate's changed before
I have to agree with TVC. The exchanges between the experts and the well informed and the deniers has given me a more detailed look at the different aspects of AGW.
I've been here lurkinga couple times a day since the inception of this blog site. I read most of the articles and love going to the commets where things get fleshed out.
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TVC15 at 11:32 AM on 27 September 2019Climate's changed before
MA Rodger @780
Thank you so much. I learn so much from you all when I post the denialist blather that deniers challenge me with.
Thanks for the link to the Rohling paper.
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scaddenp at 11:14 AM on 27 September 2019CO2 effect is saturated
" What would you say is happening going from 285ppm to 400ppm to 500ppm?"
Well simply that theory predicts that globally averaged irradiation of the surface will increase by 3.7W/m2 for every doubling of CO2; and that measurements OLR and DLR confirm these calculations.
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bozzza at 09:17 AM on 27 September 2019Using fallacy cartoons in a quiz
Where's the fallacy cartoon about Mont Blanc?
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bozzza at 09:05 AM on 27 September 2019CO2 effect is saturated
qball17, science has always been political: thats exactly how your mates got rich and powerful in the first place and why you are defending their right to remain so....
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bozzza at 08:48 AM on 27 September 2019CO2 effect is saturated
Thr insulation argument is nonsence!
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Doug Bostrom at 07:27 AM on 27 September 2019CSLDF: Events at NOAA Highlight Strengths and Shortcomings of Agency Scientific Integrity Policies
Indeed JWRebel, in an administration that has moved the Bureau of Land Management headquarters to share a builidng with Chevron Oil the Sharpie mark seems relatively trivial. But it's still worth considering the chilling effect overall when the twitstorm has passed on, leaving behind threats of retaliation against NOAA employees for telling the truth. Next time,they'll think of this and have to run an equation of "mortgage payment, or truth?"
Further to your point and CSLDF's and for detailed damage reports don't miss the link to the Silencing Science Tracker embedded above.
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scaddenp at 07:27 AM on 27 September 2019CO2 effect is saturated
"How do you feel about that the whole tread starts of with using an analogy of a water tank."
There are three level of explanation on this topic. Basic, Intermediate, Advanced. The Basic version starts with an analogy because it is trying to help someone new to the topic, without technical background, understand the issue.
You appear to be trying to disprove established science. Nothing wrong with that - science makes progress that way - but you cannot do that through pushing an analogy. Most break down at some point. You need to start with the Advanced and then move to a textbook on radiative physics if you have a strong reason to believe CO2 is saturated, but I dont think you have grasped the importance of the temperature profile.
Just remember, observations win in science. What we observe matches the theory.
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CO2 effect is saturated
PringlesX - CO2 is not saturated where it matters, at the TOA where emission to space occurs. And we have direct evidence of that, for example Harries et al 2001, which demonstrates that there is decreasing energy leaving the TOA at greenhouse gas absorption frequencies between 1970-1997, creating an energy imbalance between incoming and outgoing radiation that can only result in the entire atmosphere warming.
As to analogies - you can draw parallels between aspects of known and unknown systems with an analogy for instructive purposes, but the analogy isn't the real thing. You cannot disprove with analogies, only with the real science and system in question. In logic this is referred to as the False Analogy fallacy - easy to fall into, but best avoided.
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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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