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Comments 1301 to 1350:

  1. Skeptical Science New Research for Week #7, 2021

    jamesh:

    Look to the top of any page here. Under the "Skeptical Science" banner, you  will see a row of menu items, saying :Home   Arguments   Software..."

    Below that is a box. It says "Search". You can type in that box, and then click on "Go" below it.

    You can also  read further down below that, where it says "Most Used Climate Myths". If you don't find what you want there, at the bottom of the thermometer you can click on "View All Arguments...".

    ..and as to your comment about "stratospheric aerosol injection", since we know the effects of adding aerosols to the stratosphere - because, well, scientists have studied it and understand it, and know the principles involved - then yes, it is geo-engineering.

  2. Skeptical Science New Research for Week #7, 2021

    I did read the the complete posting on geoengineering and did not perceve that strataspheric aerosol injection had anything to do with engineering. Engineering always deals with known scientific principals.  In any case I wish to move on to the issue of the melting of polar ice sheets.  How do I access postings on that subject?

  3. Philippe Chantreau at 09:02 AM on 19 February 2021
    Skeptical Science New Research for Week #7, 2021

    Even as it is, James statement is only partially true, since enhanced geothermal can work in a much larger variety of situations, as in Soultz Sous Foret.

  4. Skeptical Science New Research for Week #3, 2021

    Jamesh,

    The "scientific consensus" argument was popular about 10-15 years ago.  That horse was flogged untill there was nothing left.  Read the articles the moderator has highighted.  There is a scientific consensus when a great majority of scientists agree that the problem has been solved.  Scientists agree that CO2 causes global warming.  The question is exactly how much it will warm and what the consequences of that warming will be.

  5. Gillett et al. (2021) global warming attribution study

    jamesh@5:

    You are not expressing yourself sufficeintly clearly. For example, you first say

    "Dr. Mann in his publication dated 01 April 19 Titled Global-scale temperature patterns and climate forcing"

    [emphasis mine], and then you say:

    "the atmosphere could not have forced the sequesteration of carbon in the earths sedimentary rocks."

    The two uses of the term "force" have entirely different meanings in these contexts.

    Mann's statement - and any statement that has to do with CO2 forcing climate changes - is due to the radiative properties of greenhouse gases. They absorb and emit IR radaition, which alters the flows of energy, and do this in such a fashion that the global balance between absorbed solar radiation and emitted IR (to space) is affected. As a result, the earth warms in response to increased atmospheric CO2.

    In your second use of the term forced, you seem to be talking about changes in the global carbon cycle. How the carbon cycle responds to the burning of fossil fuels is a different question from how increased atmospheric CO2 alters the radiation transfer.

    To claim that CO2 cannot force climate because the atmosphere cannot force geological carbon sequestration is a non sequitur.

    There are threads her that discuss the carbon cycle and how we know that the burning of fossil fuels is leading to increased atmospheric CO2. There are other threads where the role of CO2 as a greenhouse gas is discussed, including how the greenhouse gases lead to a warmer surface.

    Such confusion in what you write needs to be clarified. We can only know your thoughts by how you express them. If your writing is confusing, we have no way of knowing if you are just expressing yourself poorly, or whether you are failing to understand some aspect of the science. Right now, it looks like there is a lot you do not understand.

  6. Skeptical Science New Research for Week #7, 2021

    Geothermal energy will be practical in some areas of the US and impractical in others, the same way a "traditional" thermal generation plant will be more or less practical, dependent on such matters as fairly ample water supply. 

    Jamesh, I'm wondering: why are you reviewing/remarking on geothermal energy here? There are no articles on geothermal energy in this batch of papers and the "editorial content" ahead of this week's list has no relevance to geothermal energy systems. 

    It looks as though you've found your way to the wrong page and hence accidentally created a non sequitur.  What thread did you have in mnd?

    Moderator Response:

    [TD] I think Jamesh read only the "Geoengineering" title of this post, and assumed that meant geothermal. I let Jamesh's comment stand, because we sorta let the New Research posts act as entry points for commenters who have not yet found their way to more appropriate posts' threads. But if Jamesh continues to comment without actually reading anything first, we will start deleting the comments.

  7. Skeptical Science New Research for Week #7, 2021

    With respect geothermal, it is not new technology, and it does work but there are technical limitations.  One is efficiency,  which varies dependent on temp. difference source and discharge.  And this brings up another problem.  When you have ground water,  the source of heat has to be well below ground water in order to have an efficient system.  I know from personal experience what difference ground water can have.  Early in my career I worked in mine in Arizona where their wes no ground water,  at least above 2000ft.  At 2000ft rock in the work area was over 90dF.  I later worked in a mine in Virginia where the ground water extended below 1000ft.  Workers needed extra cloths to keep warm. My experience tells me that geothermal would not be practical in many areas of the US.

    Moderator Response:

    [TD] I removed the extra blank space at the bottom of your comment, and changed your double spacing to single spacing. Do those things yourself next time please.

  8. Skeptical Science New Research for Week #3, 2021

    My guess is that your moderator will call the following comment political, but I think my opinion counts for something so I ask your honest comment on the following;  I do recall a time when Scientists did not band together to support a view of scientific facts.  Scientists were on their own, (this was true even in The old USSR. Yosenko was Stalins favorite scientist, other scientists kept their mouthes shout)  so when they came up with a theaory they  knew they had to have facts and present a reasoned analysis.  As a good example of how the system did work I suggest you google  Steven J. Gould  and you will see the old system at work.  

    Moderator Response:

    [TD] Read the post The 97% Consensus on Global Warming. Actually read it. The whole thing, not just the title. Basic, Intermediate, and Advanced tabbed panes. Then if you still want to comment on that topic, do so there, not here.

    [TD] I changed your double spacing to single spacing. Do that yourself next time please.

  9. Gillett et al. (2021) global warming attribution study

    michael sweet @7,

    In calling N2 "a GHG and that it is 300 times more effective than CO2," the commenter @5 is probably in this particular confusing N2 and N2O, the latter of course being a GHG and with current atmospheric concentrations, providing 10% of the forcing level of CO2 from 2000-times less increase in oncentration. The "300 times more potent than carbon dioxide" can often be found on-line, this being a rounded-up value for the 100 year GWP.

  10. Gillett et al. (2021) global warming attribution study

    Hi Jamesh,

    If you want to engage successfully it helps if you do some background reading first.  For example, diatomic molecules like N2 (78% of atmosphere) and O2 (21%) do not absorb IR radiation and are not greenhouse gasses.  (Monoatomic atoms like argon (0.9%) also are not greenhouse gasses).  This is a pretty basic mistake and makes everything else you say look questionable.  Triatomic molecules like H2O and CO2 and higher order molecules like SF6 absorb IR radiation and are greenhouse gasses (< 0.1%).  This was figured out by scientists in about 1850.

    Good luck in your effort.  I suggest you read some of the basics first like the Interactive History of Climate Science at the upper left of this page.

  11. Gillett et al. (2021) global warming attribution study

    Rob

    I think you missed my point.  My purpose was to address the scientific

    basis for Climate forcing.  I think this is a valid issue,  inasmuch as DR.

    Mann raised the issue in his paper titled Global-scale temperature 

    patterns and climate forcing etc.  published 01 April 1998.  I do'not

    want to address my concerns to anyone in particular,  I just want to

    talk about applicable science.

     

    Moderator Response:

    [PS] Take this to an appropriate thread.  No more offtopic comments here please. You have already been pointed to more appropriate thread. Take the time to read the science before commenting.

  12. Gillett et al. (2021) global warming attribution study

    Bob

    My intent was to engage our audience in a discution of scientific facts.

    The central issue is climate forcing by atmospheric CO2.  The term was

    used by Dr. Mann in his publication dated 01 April 19 Titled Global-scale

    temperature patterns and climate forcing.  I think it is fair to look at the

    science behind climate forcing.  My purpose in citing geologic history

    was to illustrate a long period when CO2 in the atmosphere could not

    have forced the sequesteration of carbon in the earths sedimentary 

    rocks.  Inasmuch as the physical laws of nature haven't change I figured

    scientists might agree that CO2 in the atmosphere could not possibly

    force climate change.  To confirm the foregoing alledge fact,  anyone 

    can go online and with the aid of google,  find that N2 is also a GHG

    and that it is 300 times more effective than CO2.  All of this does make

    if one keeps in mind that at 400ppm CO2 is present in the atmosphere

    that it weights in at o.o4 percent.  N2 comes in at 80percent.  If we go 

    to the driest place on earth, probably the Sahara, we are told that night

    temps. are known to drop as much as 36deg F.  The moderating effects

    of H2 and CO2 are nowhere to be found.  Also there was an opportunity

    to run a GHG test on effecity of CO2 by running a series of tests,  starting

    with sundown  and running to sunup.  A series could have been run, but

    it was not done.  Again, I am not looking to engage any one person 

    specificately, I only want to discuss the scientific facts (as I see them)

    Moderator Response:

    [TD] Your comment is off topic, as was your previous one. Find appropriate posts for your comments, with separate comments on separate posts.

    For your claim that N2 is a greenhouse gas, you should read the American Chemical Society's post "Which Gases are Greenhouse Gases?", and if for some reason you disagree with the absence of N2's listing there, maybe post your objection in the SkepticalScience thread off the post "CO2 is main driver of climate change."

    You must also back up your claims with evidence. For example, your claim that CO2 and H2O do not affect temperatures of deserts plainly is false, but if you want to claim otherwise you need to provide evidence, along with whatever rationale you can muster for squaring that claim of yours with your note that deserts are dry. I for one cannot figure out how the cooling of a desert with a dearth of water vapor demonstrates that the presence of water vapor fails to prevent cooling.

  13. Gillett et al. (2021) global warming attribution study

    James... If I understand your question correctly, this might be a better thread to comment on. John Mason does a good explanation of carbonate-silicate rock weathering thermostat processes here:

    https://skepticalscience.com/weathering.html

  14. Gillett et al. (2021) global warming attribution study

    Jasmesh:

    Your statement " I cannot imagine..." is an argument from incredulity. It carries no weight. I don't even know what "the process" is that you are talking about.

    If you have specific things to state related to specific aspects of climate science, please use the Search function to find a topic, and place comments on that topic.

    Your comments should deal with something raised by the blog post - if not, it's probably off topic there and you need to find another topic. This topic does not discuss distant geological time - only the recent past.

  15. Gillett et al. (2021) global warming attribution study

    I appologe for the snarky remark.  Will abide with the rules next time.

     

    Moderator Response:

    [PS] Offtopic. Maybe start with "Co2 levels were higher in the past" but more detail on past CO2 and past climate on many other threads. Use the Search button on top left or review the "Arguments" page.

  16. Gillett et al. (2021) global warming attribution study

    I am an engineer by training and experience,  so I do have a scientific 

    background.  At this time, I want to point out a few scientific facts. The first

    is from a text on historical geology.  They list all of the geologic divisions

    from the permian going back about 350my to the cambrian.  We know

    that most of the carbon that is sequestered in geologic formations was

    deposited as coal, limestone and shale during that period.  Also the 

    atmosphere benefited by O2.  I think it is obvious that the process would

    have required a lot of CO2, which everone knows is the product of 

    volcanic action.  I cannot imagine that any scientist would alledge that

    CO2 has the power to drive the process,  but be my guest.

    James h. shanley, environmental safety engineer

  17. Tips on countering conspiracy theories and misinformation

    Sorry - retraction: I see that clicking downloads the .pdf! Didn't notice the little green arrow.....

  18. Tips on countering conspiracy theories and misinformation

    The links to the English versions merely point to the same page, and viewing the image has such a low resolution that it's unreadable

  19. It's waste heat

    Yes. Another give-away is the use of the term "equivalent climate change..." in front of each "boundary layer" term in the text I quoted.

    Equivalent to what?

    Equivalent to Finnegan's Finnagling Factor, or Cook's Constant, or less formally, the Fudge Factor - the ratio between what he really got and what he wanted to get.

    "If I put these totally unrealstic coefficients into my model and label them like something real, I can fit global temperatures."

    Tamino's blog is full of take-downs of this sort of curve-fitting.

    Of course, we true curve fitters know that the real explanation is Pirates.

  20. It's waste heat

    Bob Loblaw @202,

    There is, of course, the old SkS favourite when debunking nonsense like this - the identification of curve fitting. The grand modelling exercise carried out by Bian runs 1965-2018 and shows a pretty constant increase in FF+nuclear Primary Energy and also in surface temperature.

    Look more closely and, of course are we are familiar with this, the surface temperature was flat for the first few years of this period and indeed was effectively flat 1940-1970. But FF+Nuclear Primary Energy was rising at a costant rate from 1950 with a far slower rise prior to that. So pre-1965 Bian's curve-fitting would be looking a lot less than a good fit.

    Global Priamry Energy

  21. It's waste heat

    MA Rodger:

    You dug further than I had the time to do. I did look at the web page for the 2019 article, and I saw that is has information on the review. I did not take the time to examine the article or the reviews, but it may be entertaining to do so.

    I did look at the editorial board for Environmental Systems Research and did not see a single name I recognized, so it's hard to know what their background is.

    The International Journal of Environment and Climate Change is also an unkown entity. Searching Beall's List of Predatory Journals there are 690 hits for "International Journal of" and 4 hits for "International Journal of Environment", but "International Journal of Environment and Climate Change" is not on it. BIan's article from 2019 is listed as being in volume 9, and the journal seems to go back to 2011. The publisher (Science Domain International) is on Beall's list, though.

    https://beallslist.net/

    https://beallslist.net/standalone-journals/

  22. It's waste heat

    Bob Loblaw @200,
    The craziness engendered in this thesis set out in both Bian (2019) 'The Nature of Climate Change-equivalent Climate Change Model’s Application in Decoding the Root Cause of Global Warming' and Bian (2020) 'Waste heat: the dominating root cause of current global warming' is profound. Other than having access to more recent data, the second account sets out nothing new that I can see, and there is little point in spending much time examining such madness.
    I note the citations made by the second account (which are quite sparce) include two to SkS webpages, this one and 'What does past climate change tell us about global warming?'.
    So from this SkS webpage the author does appreciate that the global primary energy use amounts to just 1% of the positive forcings from AGW. Indeed, this disparity he considered too small as, in the universe inhabited by Qinghan Bian the energy employed in "useful work" is somehow swept from the planetary climate system and will not contribute to a planetary energy imbalance. Given the "perspective of thermodynamics" invoked at this point in the narrative, the blundersome efforts of Qinghan Bian seem to know no bounds.

    You point to the climate being modelled as having a pond-depth of ocean and a similar height of atmosphere. Adopting such nonsense allows temperature increases to be equated to global Primary Energy Use (bar the 20% that magically disappears in "useful work").
    The earlier account gives annual values for the energy employed heating the various components of the planet. Thus in 2017 there is 1,500Kj x 10^14 warming the ocean surface layer. The OHC measurements give the 0-2,000m warming for 2017 as a little low relative to earlier years, averaging out at 7.8Zj annual. So in Bian-money, that is 78,000Kj x 10^14.
    Some may consider this comparison a little unfair given ΔOHC is usually seen as being perhaps 80% of the heating resulting from AGW. This would put the total planetary on-going warming at some 100,000Kj x 10^14 which would compate with the 4,000Kj x 10^14 of Bian but only if the global temperature rise so far is ignored. The +1ºC extra planetary temperature which requires maintaining. If this AGW-delivered-so-far is also factored in, the extra energy flux out into space would be balancing 3.7Wm^-2 of forcing/feedback (and presumably with a ration of perhaps  1:2) giving a figure for the global forcing (20Zj  balanced forcing+ 10Zj imbalanced forcing still heating) at 300,000Kj x 10^14. So very roughly the 1% value of [Primary Energy Use]/[AGW] appears again.

  23. It's waste heat

    I have only taken a quick read of the paper, and I know nothing specific about the journal, but the paragraph on "Past Simulations" says the following (emphasis added):

    It is revealed that (Bian 2019) an equivalent climate change surface air boundary layer with a depth between 50 and 100 m (also referred to as the depth’s lower and upper layer limits), an equivalent climate change waters surface boundary layer with a depth between 0.1 and 0.2 m, and an equivalent climate change land surface boundary layer with a depth between 0.05 and 0.1 m can well characterize their respective temperature changes due to the heat entered air (Fig. 2), oceans and land from human activities. The simulations at these depths are well consistent with the observed temperature anomalies in these three components (Bian 2019). These depths are referred to as equivalent climate change boundary layers’ depths.

    The values for "boundary layer" depths are absurdly small for use in determining global temperature changes.

    • 50-100m of atmosphere is about 1% of the total atmosphere.
    • Average ocean depth is about 3700m, so 0.2m is about 0.005% of the total ocean volume. (If we only think in terms of the ocean mixed layer, which is roughly 60-100m deep,the 0.2m figure is less that 0.3% of the total.)
    • On an annual basis, land surface temperature changes extend to about 10 depth, so 0.1m is about 1% of that volume. (Over decades, the temperature changes would extend to greater depths, making 0.1m a smaller %.)

    The paper appears to model global temperature changes assuming that the waste heat is confined to those small portions of the earth-atmosphere system, and concludes that waster heat therefore "explains" global temperatures. As those very small proportions of the system are only a very small proportion of the amount that actually is heating up, the conclusion is absurd.

    It is the equiivalent of saying that the heat from a candle is capable of warming the air in a shoebox by X degrees, so when my house warms by X degrees the candle is the explanation (and the furnace is irrelevant).

    If someone can find some redeeming portion fo the paper that does any better, feel free to post it. The sole reference to the model used seems to be to another paper by the same author. It did not seem worth the effort to obtain it.

  24. It's waste heat

    I found a 2020 article on this topic.  It makes disparaging comments on the entire science of climate change based on the fact that we havent been able to stop the impact yet through our current efforts.  It discloses in the ethics section that it was completed by a guy at home in his spare time, so I also assume there is no reputable peer review.  I am just wondering if SpringerOpen online publishing is known to be a reliable, questionable, or downright fraudulent in whatbit published.  Here is the link to the report.  Thanks.  Best regards.  Brock

    https://environmentalsystemsresearch.springeropen.com/articles/10.1186/s40068-020-00169-2

    Moderator Response:

    [BL] Link activated.

    The web software here does not automatically create links. You can do this when posting a comment by selecting the "insert" tab, selecting the text you want to use for the link, and clicking on the icon that looks like a chain link. Add the URL in the dialog box.

  25. Veganism is the best way to reduce carbon emissions

    Klemet @10

    Could you please get in touch via our contact form and we'll figure out how to best proceed?

    Thanks!

  26. Veganism is the best way to reduce carbon emissions

    Over the years I've had a number of friends who tried to become vegetarian and failed. It wasn't for lack of trying or lack of discipline. They said their meat cravings became very intense after going veggie. Their bodies were telling them they needed it.

    Humans have been omnivorous for many hundreds of thousands of years. As I've read, our control of fire and access to calories through hunting game is largely responsible for the evolutionary development of our large brains. Suffice to say, to expect all of humanity to go vegan is to swim against a very strong current.

    We are going to have to find ways to reduce the impacts of animal agriculture coming decades, but as Michael Sweet points out, it's probably going to require economic benefit. Companies like Beyond Meat seem to be taking that strategy to heart.

  27. Veganism is the best way to reduce carbon emissions

    Klemet,

    Even if becoming a vegan was a huge benefit to the climate problem I doubt that very many people would choose to become vegans.  People like to eat meat.  Very little renewable energy was being built until it became economic.  They are not building record amounts of wind and solar in Texas to save the world.  They do it to make money.  I think that if we tell people that becoming a vegan is required to mitigate climate change they will just say no.  Most people will not become vegetarians when they are told it will improve their health.  Why would they become vegetarians to try to save the world?

    All the future energy plans with no CO2 emissions that I have seen include agriculture producing meat at the current rates.  A frequent poster here at SkS says that using the Savoy method of raising livestock you can sequester large amounts of carbon in the soil.  Do we really have to become vegans?

    My brother's family were vegetarians while raising their children.  They are well educated and ate balanced meals.  Their two children are both shorter than the parents.  To the casual observer it appears their height was stunted by their diet. 

    Good luck with your vegan message.  I think that we need to concentrate on messages that are more easily sold to the general public.  Like build out more renewable energy because it is the cheapest source of power and will cost less.

  28. Veganism is the best way to reduce carbon emissions

    Klemet... For me, becoming a vegetarian was more of a health decision I made for myself at the age of 21. Originally, I tried being a very strict vegetarian, for no other reason, I think, than youthful enthusiasm for the idea. Later, I spent a summer bicycle touring in the Alaska interior and was faced with eating fish on a number of occasions. Fish is a ridiculously healthy dietary choice, so I became what I believe is now called a "pescatarian." (Though, for me the nuances of labels is like arguing angels dancing on pin heads.)

    Later, I married a woman from China, which comes with a whole host of dietary adventures. One year we were in Chongqing for Chinese New Year. My wife's 80 year old grandmother got up at probably 5am on New Years day and proceeded to make pork dumplings for the entire, large extended family, as was obvious she'd done for most her entire life. I was faced with an interesting decision: do I say, "No thanks, I'm a vegetarian" or do share in this beautiful aspect of my wife's family and culture? The decision was simple to make.

    Ultimately, I believe diet has to be a personal decision for people. I believe it drives people away to tell them they're bad if they do one thing or another. Too often I see veganism taking that approach and I think it does more damage than good. Too often I've seen vegans trying to make the case that becoming vegan is a panacea for fixing climate change, when it's just not. 

    On the issue of full supply chain, I would disagree. Consider a world where overall diet remains unchanged but we completely decarbonize buildings, and surface and air transportation (yes, I know, big challenge on air, but consider it). Essentially, decarbonizing buildings and transportation are untethered to animal agriculture. So, what then is the impact of animal agriculture? I'm pretty sure you're back down to something on the scale of single digit percentages of current carbon emissions.

  29. Veganism is the best way to reduce carbon emissions

    @Rob Honeycutt : I apologize if I misunderstood your question, Rob. I'd say that I haven't see the IPCC clearly stating "animal agriculture is responsible for X% of emissions" anywhere; but as they use the FAO's numbers in their repport on the issue (which leads to their conclusions on the question, specifically about the sustainability of a vegan diet), I thought that this was enough of an endorsment.

    Regarding the rest of your comment, I'd say that you perfectly point out why we see so many different numbers when we talk about the impacts of animal agriculture on GHGs emissions, or on over environmental issues (e.g. water, land-use, etc.).

    Personnaly, I'm more of a "full supply chain" kind of person. For example, many questions and debates arise about the quantity of ressources (e.g. water) needed to produce a pound of meat/milk/etc. Advocates of animal agriculture will say that it's not that much, especially when it comes to water; but when you take into account that crops and forage has to be given in huge quantities to the animals in question (and that a lot of these ressources/energy are "wasted" as base metabolism, rather than becoming part of their bodies/secretions that we then eat), this changes everything. However, from my point of view, it is hard to argue that these crops and forage would be produced if not to be eaten by those animals. Hence, I deem it a part of the impact that animal agriculture have, just as transportation/building aspects. Might be naive of me, though.

    Concerning the nutritional value of whatever is used to replace, I fully agree. That's why I'm always fond of expressing GHGs emissions or environmental impacts per calorie or gram of protein rather than in kg of food produced.

    Still, and I might be wrong on that, but I think that we're starting to have a concensus on those aspects. Conclusion of articles such as the one from Poore and Nemecek are echoed in other meta-analysis (like the one from Clark and Tilman), and it kind of makes sense from my point of view : if you want to eat things coming from a step above in the "food chain" (i.e. animal bodies or secretions), then you have to contend with the fact that a huge amount of energy/ressources given to the species you feed are not going to become "food" for you, but are going to be lost in the transition from one step of the chain to another (e.g. metabolism, etc.). If I remember my ecology lessons, while the notion of "food chain" is now obsolete, there was still talk of about 80% of energy lost from one step to another (e.g. plants to herbivores, herbivores to primary carnivores, etc.). I don't know if this number still holds up today; but in any case, that makes for a low-yield ressources wise, which is what is reflected in those conclusions, I believe.

    40 years of being vegetarian is a pretty long time, though ! I don't want to ask to much personal questions in comments, but I'd be very curious to know what got you to change such a long time ago, where vegetarian diets were not the trend that they are today. But I do agree with you that science on the topic is very often misguided, and use as a weapon rather than as a learning tool. I guess that it's such an emotional topic though that it is to be expected. In my experience, listening to the fears that can arise from both sides (e.g. the fear of having animal products labelled as illegal in the future, or the fear of knowing that animals are killed without good reasons) can lead to some defusing of the issue.

    @BaebelW : If help if needed to maybe re-write some things or propose a more precise alternative, please let me know. Skeptical Science is a site I greatly admire, and as a PhD student, I should be able to write a proposition in a relatively proper manner. I imagine that authors must already have a ton of work on their hands, and I don't want to add to much to it. Still, thank you very much for the consideration, and thank you for all of your good work !

  30. Veganism is the best way to reduce carbon emissions

    Thanks everybody for your comments, which we'll need some to time to assess, given all the feedback and references included and the volunteer nature of our team.

  31. wilddouglascounty at 00:48 AM on 14 February 2021
    Scientists sceptical of new bat study linking climate change to Covid-19 emergence

    It is probably safe to say that anthropogenic induced changes in ecosystem composition have been major contributors to the changes in bat species in the region concerned, with climate change, habitat destruction, human population increases and related infrastructures both in this region and surrounds being in the mix of variables at play.

    I mean, really, is there not a place on the planet where human habitat destruction hasn't been a significant variable in determining the range and species composition of any given ecosystem?  And the same with the shift in climate?  Trying to attribute causality to either one or the other is kind of like attributing heads on a coin to the exclusion of the tails on the same coin.

  32. 2009-2010 winter saw record cold spells

    I misspoke in post 23.  There were hundreds of monthly records in the "Summer in Winter".  Since it was winter no all time hot records were set.  the summer was still hotter than the winter.

  33. 2009-2010 winter saw record cold spells

    John Hartz,

    Reading your link and then searching a while online I see reports that the cold spell you report is the coldest in Europe in the last 10 years.  I found a report that one country set a cold record in a different cold spell in the middle of January.

    Going to the National Climate Data Center (USA national) they have a record temperatures page.  Settting the page on global records (they do not have a European only page) I see in the last week there were 837 cold records and only 273 daily high records.  In the harder to achieve monthly records there were only 12 low records in the past 7 days with only 2 high records.  There was only 1 all time cold record globally in the last 7 days and no hot records. 

    Trying to measure a longer time in the past year there were 50,000 daily cold records and 109,000 hot records, hardly an ending of global warming.  For monthly records there were 2100 cold records and 7,000 hot records.  For all time records there were 32 cold records and 487 all time hot records.

    In Europe last week it was cold compared to the past 10 years of hot weather.  It was normal weather for 100 years ago.  The denialists can only remember the past ten years so they think it is cold when it is really not.  In addition, they often say record snow means it is cold.  Record snow is not the same as record cold.  Science predicts that in a warming world there is more precipitation.  In cold areas that means more snow.

    By contrast, the Summer in Winter in the USA and Canada (in March 2012) produced thousands of daily records and hundreds of all time records.  In some locations the low temperature at night was higher than any previously recorded high temperatures!

    Of course, regular readers of SkS are already aware of this.  The NCDC records page is a good location to counter this denier myth.

  34. CO2 lags temperature

    brneilsen @629,
    I'm curious as to the origin of your 'greenhouse gas response' equation T=3.2563ln(C)-3.0323. And if there were any merit in such an equation, I'd be interested to learn how it 'yields' a "0.95 degC" boost to global ice age temperatures resulting from a 190ppm to 280ppm rise in CO2. My abacus (which I would be the first to admit is not always reliable) 'yields' +1.26ºC using this bizarre equation.

    The usual calculation of CO2 forcing is ΔF = 5.35 x ln(CO2[1]/CO2[0]) which gives a forcing of +2.07Wm^-2 and a thus 'direct' impact on global temperature of+0.56ºC which would cause climate feedbacks that would perhaps triple this value to +1.7ºC.
    The global average temperature rise out of an ice age is usually reckoned at +5ºC to +6ºC so this calculated CO2 forcing would perhaps be responsible for a third of this temperature rise. And this result fits with assessments which find the contributions to deglaciation warming to be roughly 50% surface albedo, 37% GHGs (of which CO2 is the major player) and 13% atmospheric albedo.

  35. Increasing CO2 has little to no effect

    devcarr @427,
    You ask about the altitude of the planet's IR emissions out into space, this ERL as you term it. The physical altitude is dependent on wavelength so there is no single altitude.

    The graph below shows contours of absolute temperature and when these emission altitudes are within the troposphere, the altitude can be inferred from these temperatures. The big 'bite' out of the emissions spectrum at 666 Wavenumber is due to CO2, the smaller one at 1050 Wavenumber is ozone. Note the small central spike within each of these 'bites'. These are caused by the emissions altitude of the central region of these wave bands being so high that they are up in the stratosphere where the temperature starts to rise again. Thus the spike yields a higher emissions temperature than the rest of the 'bite'.
    Being up in the stratosphere means that as the central spike expands with additional CO2, this specific region of the affected wave band will act to cool the planet while other parts of the 'bite' expand to warm the planet. The net effect remains a warming one.

    emissions spectrum from Clive Best

    Significant change in CO2 concentration in the atmosphere will impact the shape of the 'bite' at 666 Wavenumber markedly, as well as kicking off other 'bites' (or perhaps 'nibbles') close to the ozone 'bite'. This is described in Zhong & Haig (2013) 'The greenhouse efect and carbon dioxide'.

  36. 2009-2010 winter saw record cold spells

    Here we go again!

    Climate deniers are using a spell of unusually cold weather in Europe to incorrectly argue that CO2 emissions are not warming the planet.

    How global warming can cause Europe's harsh winter weather by Jeannette Cwienk, Environment, Deutsche Welle (DW), Feb 11, 2021

  37. Increasing CO2 has little to no effect

    devcarr @427,
    I assume your surprise at the graphic @425Response showing the AGW temperature rise halting as soon as emissions stop because your questioning didn't expect the residual warming-yet-to-come to be pretty-much balanced by the reduction in climate forcing. Following the end of emissions, the GHGs are no longer being boosted by those emissions but instead falls as GHGs are naturally drawn out of the atmosphere.

    Perhaps your expected a response to your question @425 to be for the time for warming to end and equilibrium to be reached for a constant level of GHGs. This is of course a different question.

    The radiative imbalance is running at something like 1 Wm^-2 and if that were allowed to play out by keeping GHG levels constant, it would take a century or more before equilibrium is effectively achieved, with ECS=+3.0ºC suggesting an additional +0.8ºC. The time for this is uncertain as it is the longer-term processes that are poorly quantified when the ECS is assessed, and the value of ECS is famously poorly bounded.

    Hansen et al 2011 fig4

    The left-hand graphic here is Fig 4a from Hansen et al (2011) 'Earth’s energy imbalance and implications'. It shows a large part of the warming-to-come appearing in the first decade and that followed by a further large part in the following century. The big uncertainty is in the longer-term warming and this is the major cause of ECS being so poorly defined. And that long-term warming is not entirely a thermodynamic thing. Major longer term warming due in albedo can be caused by a minor and quite insignificant temperature imbalance acting over a long period. So any such long-term warming will result from the warming-already-achieved (+1.0ºC) as well as warming-to-come (+0.8ºC). And so if climate forcing were maintained, this longer term could then become quite significant.

  38. Increasing CO2 has little to no effect

    Devcarr:

    The emission altitude varies with the wavelength of IR light that you examine.  Some IR is emitted from the surface while other wavelengths are emitted from 15 kilometers up.  The average emission altitude is about 10,000 meters which is near the average height of the troposphere.  The top of the troposphere also varies in height.

    The temperature in the troposphere varies according to the lapse rate.  The lapse rate is about 6C per kilometer (this also varies).  Temperatures have increased about 1.2C.   !.2 devided by 6 is .2 km or about 200 meters.  That is a very rough estimate.  I was very surprised when I first learned that the increase in the emission altitude is so small.  (the change is slightly different for different wavelengths of IR light).

  39. CO2 lags temperature

    typo corrections: Milankovitch; interesting

  40. CO2 lags temperature

    This has been interetsing, and explains a lot about the confusion in the general public because of prior missives that CO2-Ice core data were proof of a causive link, when it was more likely a result. NASA covers this in the section on Milankovich theory, but fail to actually split the response from CO2, which is easy to do, since the greenhouse gas response is easily modelled with the equation T=3.2563ln(C)-3.0323, where T is the Earth's average temperature in degC and C is the CO2 concentration in ppm. From the ice cores, the change from 190 to 280ppm yields a contribution of 0.95 degC, so minor compared to the overall change of 7-8 degrees.

  41. Increasing CO2 has little to no effect

    Thanks. I see it is also called the Effective Radiating Level (ERL). But I can't find information on how much is has increased in altitude.

    I am surprised by the graph showing that temperature rise stops almost immediately when emissions stop. I would think temperature would rise until the Effective Radiating Temperature, at the ERL, caused enough outgoing radiation to balance the incoming radiation from the sun. Does that happen so quickly that it can be ignored?

    Is the ERL very close to the top of the troposphere, below it, or above it?

  42. Increasing CO2 has little to no effect

    devcarr @424... I believe that's referred to as emission altitude or effective emission height.

  43. Increasing CO2 has little to no effect

    If we stopped emitting CO2, methane, and nitrous oxide tomorrow, how much would the average surface temperature rise before we reached equilibrium?

    Moderator Response:

    [DB]  Figure 3.9 (page 99) shows the persistence of elevated temperatures after emissions cease:

    "regardless of when emissions cease, GMST remains approximately constant for the subsequent millennium"

    Temperature persistence

    That's based on:

    Gillett et al 2011 - Ongoing climate change following a complete cessation of carbon dioxide emissions

  44. Increasing CO2 has little to no effect

    What is the term for the layer near the top of the troposphere, where most infrared actually radiates away from the earth, because the air above has too few GHG to stop it? Is it just called the top of the troposphere? How much has that radiative layer gained in altitude since the start of the industrial revolution? As I understand it, that is the "extra blanket" that has forced warming of the earth.

  45. 2021 SkS Weekly Climate Change & Global Warming Digest #6

    Xulonn:

    While I can appreciate your point that this use of "natural" has a long history, I think part of the idea of changing the term likely comes from the common "skeptical" argument that humans are not affecting climate because the changes are "natural" - i.e., calling it "natural" suddenly takes humans out of the equation.

    If you look at the Arguments list here at Skeptical Science (View all Arguments, in the sidebar near the bottom of the thermometer, or with this link: https://skepticalscience.com/argument.php), the word "natural shows up there a lot.

  46. 2021 SkS Weekly Climate Change & Global Warming Digest #6

    Certainly the motive for such a change in language is laudable, but the above proposal to rename "natural disasters" just doesn't resonate with me, an old guy with a degree in conservation of natural resources from a major university. 

    I prefer the use of pronouns than to try to artificially revise language using artificial "new-speak".

    The below general definition for "natural disaster" as used in the scientific community remains valid in my world.  One must also realize that "disaster" part of the phrase is related to the has nothing to do with the state of physical earth processes without humans, but only the fact that humans (or perhaps other species) are impacted makes it a "disaster":   

    Natural disasters are catastrophic events with atmospheric, geological, and hydrological origins (e.g., droughts, earthquakes, floods, hurricanes, tornados, wildfires, landslides) that can cause fatalities, property damage and social environmental disruption).

    Of course, some "natural disasters" have been caused by - or made worse for humans - for centuries, long before AGW/CC.  Consider dam failures, landslides, and wildfires caused by arson or accident, and they are still called natural disasters. 

  47. Increasing CO2 has little to no effect

    Here are the visualisations of 0.041% CO2 and the effect of molecules being so very small.

    VISUALISATION 1

    Although CO2 is only 0.041% of the atmosphere by volume, because air molecules are so very small, there is zero chance of a photon exiting from the surface into space without encountering a CO2 molecule; indeed many many CO2 molecules. This is simply because molecules are so small.

    Imagine if this were not so. Imagine if molecules were 12km in diameter and the atmosphere as a result a sheet of air just one molecule thick. Crazy but imagine.

    Only one part in 410 million of the world's surface would then have a giant CO2 molecule hanging over it. That is one part in 2,439. Thus from 99.959% of the planet, IR on a journey straight out to space would never encounter a CO2 molecule.

    But molecules aren't that big. For one thing, they are not arrayed shoulder-to-shoulder but have a bit of room to whizz about, and spin and vibrate. To scale*, a CO2 molecule relative to the volume of atmosphere it occupies would be roughly 1km in diameter we gave it 12km of room to sit in. And if we now allow for the empty space round our CO2 molecules, the chances of free passage straight out into space is 187-times more likely*. So we can say for a single-molecule-sheet atmosphere, the likelihood of free passage is 99.9997807%. and the chances of hitting CO2 is just 1-in-456,000.

    But molecules aren't 1km in diameter. So let's make them a bit smaller, say 1m in diameter. In a 12km-deep atmosphere, the chance of a free passage without hitting a CO2 molecule in one of the thousand layers of molecules sitting in their 12m square cubes above you is now 0.999997807^1000. So the chance of hitting CO2 is 1-in-3.

    The chance of a free passage is becoming less certain for an IR photon.

    But molecules aren't 1m big. And the smaller they get, the chances of a free passage shrink. With 1dm molecules, the chance of a free passage becomes less likely than not, 60-to-1 against. At 1cm, 645 quintillions-to-one against. The odds of free passage disappear as the size is reduced, at 1mm 1.25 x 10^187-to-1 against and quickly becoming so large that calculators cannot cope with such large numbers. And a CO2 molecule is actually 3 million times smaller than 1mm.

    I shoulkd add that while it is true that not all CO2 molecules will be in a state to absorb an appropriate IR photon, the odds are so great, that is not very significant.

    (*The usual number given for the size of a CO2 molecule is 0.33 nanometres diameter. From avogadro's number we can put the number of atmospheric molecules at 10^44 while our visualisation has an atmospheric volume of 510e12 x 12000 = 6e18 sq m. That would put each air molecule in a cube 4 nanometres wide. The box size is 12-times the diameter of a CO2 molecule. Within the projected box area of 16 sq nm, a CO2 molecule would project an area of 0.085 sq nm or one in 187 of the box projected area.)

    VISUALISATION 2
    There is today 3.2 trillion tons of CO2 in the atmosphere. The area of the earth is 510 million sq km or 510 trillion sq m so there is [3.2/510 =] 0.0063 tons CO2 above each square metre of the planet. The s.g. of dry ice is 1.7 so the volume of that 0.0063 tons CO2 in solid form with all the molecules stacked together is [0.0063/1.7 =] 0.0037 cu m. If you therefore spread this CO2 evenly over that square metre of planet Earth, you would get a sheet 3.7mm thick. And because there are [6e23 x 1 e6 / 44 =] 1.36e28 CO2 molecules per ton, the 3.7mm sheet will be 10.5 million molecules thick. (That puts the size of a CO2 molecule at 0.35nm.)

    Of course, in the real atmosphere, the CO2 is spread out up into the stratosphere but an escaping IR photon on a straight-up journey will still have to negotiate 10.5 million CO2 molecules for a clean escape. In the real world, a very large proportion will not impede an individual IR photon so the path length of an IR photon is greatly underestimated by this visualisation. But it does demonstrate that the 0.041% concentration does not in any way prevent CO2 acting as a very powerful GHG.

  48. Increasing CO2 has little to no effect

    Rob Honeycutt @421,

    I don't know of anybody attempting a model of Earthly climate without GHGs, with the exception of Lacis et al (2010) which modelled the cooling from present conditions up to the point when the ice-formation reached the ocean bed, that 50 years into the run. Their model still shows 10% of present atmospheric water vapour by that time.

    Regarding a role for water vapour, my own thoughts turn to our recent ice ages and how a cold planet moves water poleward to form very large polar ice caps. These would be larger still without GHGs. And without interglacials to melt them, the ice caps would presumably become in-the-main part of geology. Outside the tropics I'd assume there would be nowhere with noon-day temperatures capable of forming liquid water. And if it entered the atmosphere from there, any water (or indeed sublimed ice) would tend to be carried poleward.

    What the climate would be like with no GHGs, with atmospheric circulations no longer driven by high-altitude energy loss to space but solely by the larger surface temperature gradients? I think there are too many unknowns to speculate intelligently.

  49. Why does land warm up faster than the oceans?

    AerosGreen:

    Regarding ocean temperature gradients, I think you are missing the aspect that ocean circualtion at depth is also driven by salinity differnces (which cause density differnces)

    On an annual basis, land temperature cycles only influence the top 10m or so. The ocean mixed layer depth (mixed by surface winds - ie.. interacting more closely with the atmosphere) is more like 60-100m. So increased heat capacity plus much more volume.

    TIme constant for the mixed ocean layer is decades.

    For deeper oceans, we're talking hundreds of years for circulation patterns to run their course - so adjustment to surface changes is very slow.

  50. Why does land warm up faster than the oceans?

    Still confused about the answer above under "Warming Contrast". Specifically, "we would expect the contrast to disappear at equilibrium once the oceans have had sufficient time to warm up". Sounds like a statement made by a scientist that doesn't understand oceans.

    Change in temperature is a function of the amount of heat added (heat added over water is a bit less than the amount of heat added over land but we can ignore that for now) divided by the specific heat of the material (let's say that the ocean c is four times that of land) and mass of the material (the last one is a big clue).

    Land and oceans have opposite thermal profiles with depth and the mass of water is literally in a constant state of motion and mix.

    o Land has an internal heater so it warms with depth (about 3C per 100m). So the heat gained at the surface is primarily lost only to the atmosphere (at a rate propotional to the thermal gradiant).

    o Oceans cool with depth (nearly 1C per 100m for the first 1000m). And sea surface temperatures mix with other thermoclines via a variety of processes. So temperature is lost to both the atmosphere, which is on average always colder, and to deeper depths, which is also always colder. And once again, at rates that are propotional to their thermal gradients.

    If a model did show the contrast disappearing, wouldn't that be proof positive that the model is wrong?

    The statement going through the section on Heat Capacity was great. Add ocean turbulence (relatively rare on land) and I'm guessing those are the major factors.

    Think of it this way. Land is a sheet of aluminum foil laying next to your pond.

    How far off am I?  

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