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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Recent Comments

Comments 20201 to 20250:

DrBill at 02:31 AM on 14 April 2017

Breathing contributes to CO2 buildup

Philippe Chantreau " I am not sure what you are trying to say. CO2 exhaled by animals is not, and can not be, a net addition to the carbon budget."

No one said it was a net addition to the carbon budget. And your clarification of what does add to the carbon budget actually helps identify my challenge to IPCC and their inadequate accounting/summarizing. [FWIW, the equation I showed, Tom, was directly copied from their 2005 Report that I used, and their dismissal of any CO2 but industrial has been shown multiple times in many forums, and informed my angry analysis.]

In any given year, CO2 comes into the atmosphere from industry, transportation and respiration. Its presence is all it takes to have any putative effect, not where it came from or what source. If the atmosphere reacts to the presence of CO2, it does so without regard for its history. The emphasis on its history is the bias in IPCCs conclusions.

While I'm at it, Tom, your analysis of what I said does little to change my point, as expressed in the paragraph just above. I said 40% more, and you want to argue 33%...tomayto tomahto...they found industrial CO2 and stopped accounting. On the other detail (D), I used UN herd records for my animal calculations, added to it some lesser quality estimates of insect population (rounded down not to be too shocking), and worked with the same kind of growth curve you posted earlier in Fig 5.

Tom Curtis at 16:50 PM on 13 April 2017

Breathing contributes to CO2 buildup

Dr Bill Hoffman @95:

A) You say:

"As we breathe in 400 ppm CO2, we do not exhale "about ten times that amount", so the premise is incorrect. We exhale some 100 times that amount, about 40,000 ppm (4% CO2)."

That is correct, but it is not a claim made in the Original Post. Rather, it is an error by the AGW denier, "Ian Plimer" which was merely neglected as being trivial relative to the gross error rebutted in the OP, and which you appear to repeat.

B) You further say the IPCC is "...they focused entirely on industrial production...", but that is simply false as shown by the IPCC's summary diagram of the carbon cycle shown below:

Note that the non industrial elements are determined by in-situ surveys, satellite observations, changes in isotope ratios, all of which are used to validate models. For example, here is a paper analysing measurements of Dissolved Inorganic Carbon and comparing the result to earlier estimates. And here is a review of data relating to anthropogenic emissions from LUC. Your assertion in your video that "LUC" represents simply "a factor to allow adjusting" (8:44), ie, is merely used to balance the books is simply false. At best it represents an overwhelming ignorance of the topic on which you chose to lecture. The equation shown at that point in the video is also entirely of your own manufacture, so far as I can tell. The IPCC TAR (2001), for example, shows the following elements in the carbon cycle:

(For clear image of each panel, go here.)

As the IPCC TAR was the report immediately preceding your presentation, your employment of a truncated equation of the carbon cycle that does not even include vulcanism shows you to be, at best, completely ignorant of what the IPCC claims. Never-the-less, you feel qualified to make repeated false claims about what the IPCC purports to understand, and how they arrived at those conclusions.

C) Your model as shown on the video purports to show 100 Gt-CO2/yr (27.3 GtC/yr) emissions from respiration in 2004 (13:35). You then show an estimate of the increase in CO2 emissions by animals of about 10 Gt-CO2/yr (2.7 GtC/yr) by 2004 relative to 1900(?) (14:36), which you claim (15:54) to be about 50% of anthropogenic industrial emissions. Anthropogenic industrial emissions in 2004, however, were 7.78 GtC/yr. Your "accelerated conversion" was, therefore, just over a third of industrial emissions, and less than a third of industrial emissions plus LUC.

D) Whether or not that represents a genuine increase in emissions depends on what you calculated, which is very far from clear. To avoid excess length, I will discuss it in a following post.

Philippe Chantreau at 11:58 AM on 13 April 2017

Breathing contributes to CO2 buildup

Yes it is just you. "Ad hominem" means that an argument is attacked on the basis of the character of the one who makes it. An example would consist of saying that someone is a sleaze ball and therefore what they say is wrong or invalid. That is a logical fallacy, as the character of an individual has no bearing on the validity of the argument, which is to be judged on its own merit. I am surpised that a "serious scientist" could be confused on that point. If an argument is indeed removed from rational thought, it has no merit.

As to the rest of the post above, I am not sure what you are trying to say. CO2 exhaled by animals is not, and can not be, a net addition to the carbon budget. The only way atmospheric carbon can see a net increase is by injecting some that was taken from an otherwise stable reservoir that kept it away from the atmosphere, such as the crust. Animals do not create CO2, nor do they have the possibility of fetching it in such reservoir, only humans have the power to do that. Furthermore, the majority of animals now existing on Earth are dmoestic animals, i.e. the result of human activity, many of them indeed the result of industrial agriculture. Industrial.

Eclectic at 11:54 AM on 13 April 2017

Breathing contributes to CO2 buildup

DrBill, I watched the first half of your 30 minute Youtube presentation (from 2006).

Frankly, the arguments put forward were appallingly poor. So appallingly poor, that it woud be impossible for the second half of the talk to redeem the whole 30 minute venture and pull the fat out of the fire. The arguments put forward were so fundamentally wrong in science, as to make your presentation a nonsense. So much so, that it would be tiresome to enumerate & discuss all the errors.

You said you presented your ideas to Science magazine — and were rejected (as being "not of general interest"). DrBill, the Science editors were being polite to you. They should simply have posted your submission back to you, marked with a one-word red-pencil comment: "Nonsense".

Your youtube video is a complete waste of viewers' time.

Mal Adapted at 10:23 AM on 13 April 2017

Heartland: What's your story?

fishfear,

Whether you're a professional research scientist or an interested layperson, it's important to know what sources of scientific information are reliable. Texas State Climatologist John Nielsen-Gammon has spoken and blogged about Scientific Meta-Literacy:

But there’s an important lesson here about how we decide which scientific statements to believe and which ones not to believe. Those of us who are trained scientists but who do not have enough personal literacy to independently evaluate a particular statement do not throw up our hands in despair. Instead, we evaluate the source and the context.
We scientists rely upon a hierarchy of reliability. We know that a talking head is less reliable than a press release. We know that a press release is less reliable than a paper. We know that an ordinary peer-reviewed paper is less reliable than a review article. And so on, all the way up to a National Academy report. If we’re equipped with knowledge of this hierarchy of reliability, we can generally do a good job navigating through an unfamiliar field, even if we have very little prior technical knowledge in that field.

Shortest version: if you get your climate science information from the peer-reviewed reports of working climate scientists, you'll get the closest picture of the truth. For a highly credible review of all the evidence for AGW, however, no source can be considered more trustworthy than the US National Academy of Sciences, founded by Congress in 1862 "to advise the nation on important scientific matters." Since then the NAS has scrupulously resisted all efforts to politicize its advice. New members are elected by the existing membership, and only the most widely- and well-respected candidates are so honored.

Two years ago the NAS and the Royal Society of the UK (chartered by Charles II in 1662) jointly published a 34-page booklet titled Climate Change: Evidence and Causes. It's written for educated non-scientists like yourself, and is free to download at the link. It offers a brief tutorial on climate basics, and addresses 20 questions laypeople often have about anthropogenic climate change. Links to primary sources are provided throughout.

In the Foreword to the booklet, signed by the then-presidents of both societies, the first two sentences are [all-caps in the original]:

CLIMATE CHANGE IS ONE OF THE DEFINING ISSUES OF OUR TIME. It is now more certain than ever, based on many lines of evidence, that humans are changing Earth’s climate.

I have not made an argument from authority, but from scientific meta-literacy. If you don't trust the NAS and the RS, why would you trust anyone else?

DrBill at 10:11 AM on 13 April 2017

Breathing contributes to CO2 buildup

+RH It's nice to see the comment has not been removed on the basis that "it clearly puts you outside of any rational scientific debate". Seems to me pretty close to argumentum ad hominem, but maybe that's just me. Frankly I resent the implication that contradiction is "clearly" outside of anything.

First, the level exhaled you led with was completely erroneous, and you did not dispute that, so you make your entire argument that the C was always there and we just recycle it, and disregard your first error.

And I already answered that "recycle" argument. The CO2 exhaled by all animals (and their number is growing, along with their exhalation) is in addition to the CO2 created by industry for any given year, and, while isotope analysis can identify that produced by burning fossil fuels (less and less distinctively as exhalation goes on), any warming effect claimed cannot discriminate between that which has increased due to industry and that which is exhaled by increased population of terrestrial animals.

Thus, it is not enough to conclude that the world's industry it causing anything (the idea of CO2's effect is not for this thread), while any official body (such as IPCC) simply dismisses it, and your counterargument seems to support such dismissal.

I put it to you that if your bank were to say that it paid 0.5% on your average current balance, and then excluded 30% of your balance because it was too recent, you would not bank with them any more.

More significantly, imo, if any bank tried that, you would report them to the state banking commission. IPCC is that bank, and their accounting is that faulty.

RH, I'll ask you to keep the condescension down to a low roar. I am a serious scientist. I hope skeptical science has a few whose skepticism doubts the received wisdom of AGW alarmists and not somehow only that from "deniers". Doubt is the basis for advancement in the sciences. It should not preselect. That's just prejudice, not skepticism.

Moderator Response:

[JH] Sloaganeering and moderation complaint deleted.

Please note that posting comments here at SkS is a privilege, not a right. This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter.

[RH] Bill, while your original post was worthy of a complete deletion, it is sometimes instructive for other readers to leave such egregious examples where people think they know more than the entire rest of the global scientific community. That said, your tone and approach to this conversation are rapidly headed toward you being banned.

We encourage open dialogue here at SkS with caveat that people stick to the science. Drop the aggressive rhetoric and you might have a productive learning experience here.

chriskoz at 07:23 AM on 13 April 2017

From the eMail Bag: A Deep Dive Into Polar Ice Cores

I have a question:

What's the reason Δ-age on Figure 6 varies so much with time? For example WDC core used to have Δ-age ~500 at 19ka and then dropped to 200 at 17ka. How did we find that Δ-age varies so much?

The article explains the Δ-age is the consequence of the surface parameters that dictate the speed of firm to ice transformation. Then it explains the Δ-age distribution. But it does not clearly explain how we know the actual value of Δ-age - or its mean value if we're talking about a statistical variable - as shown on Figure 6. Can the Δ-age be actually measured, e.g. by comparing the isotopic fingerprints of some components of gas boubles and surrounding ice?

Bob Loblaw at 11:10 AM on 12 April 2017

Welcome to Skeptical Science

curiousd:

Images have to be located on a web-accessible server somewhere, not on your local hard drive. Then switch to the Insert tab and click on the picture of the tree (on the left). Enter the URL for the image (hence the web-accessible restriction) and complete the form. Try to make sure the image isn't too wide (500 pixels).

More hints are available on the Comments Policy page (link in red just above the Post a Comment box...)

ubrew12 at 10:43 AM on 12 April 2017

Heartland: What's your story?

fishfear@18 said "I have a BS in Physical Science...[and] a MBA..." The issue here, as the author relates, and as I picked up on earlier, is that our children have neither. They go to elementary school to learn what we, in general, accept (for example: we live in a 'Democracy'). The subtleties must come later, after the BS (well, more like a 'Dollarocracy', but close enough). With the vast expert consensus (and consilience) for anthropogenic global warming, do you really want us to teach our kids that your BS is relevant (I mean, to more than just yourself)? I think, at first blush, most people would think that profoundly egotistical of you. You're not the only person who has studied Science, after all. Go ahead and own your skepticism, just don't tell the rest of us (and especially don't preach to our children) that it 'trumps' the overwhelming scientific consensus on Climate Change by people who have actually competed to make the team of 'experts' on the subject. It's like saying if only you'd been made Quarterback of the Atlanta Falcons, they would have won the last Superbowl.

curiousd at 10:33 AM on 12 April 2017

Welcome to Skeptical Science

Hello All,

I used to know how to post figures and graphs. There was some web site that lets you post small images which have a URL, I think. I may be needing to do this in the section on Modtran Infrared Light in the Atmosphere. Could someone refresh my memory on how to post images in Skeptical Science posts?

Curiousd

DrBill at 08:51 AM on 12 April 2017

Breathing contributes to CO2 buildup

Since I addressed this very topic at length in my YouTube video https://www.youtube.com/watch?v=9ixT-_MYZgY&spfreload=10 I will only spend a couple of moments addressing the main subject of this thread.

1. As we breathe in 400 ppm CO2, we do not exhale "about ten times that amount", so the premise is incorrect. We exhale some 100 times that amount, about 40,000 ppm (4% CO2).

2. It is not a few cows that have CO2 (and I didn't even consider the trivial issue of flatulence that so fascinates the AGW humorists), but all the herds of animals, and all terrestrial animals, including rodents and insects, that contribute CO2 to the atmosphere. Indeed the mass of all other living things on land far exceed and far exceed in CO2 production, human exhalation. I had no basis for calculating marine sources, and for that matter did not include the direct release of CO2 by oceans, springs, grottoes or even volcanoes.

3. The CO2 production that I found in my meta study as shown in the video was growing, and growing at the same rate as the CO2 reports put out by IPCC showed (what a surprise as the curve is the same shape for human population growth), but *they focused entirely on industrial production* in intentionally misleading people imo, and my data showed that the total terrestrial animal production was 40% as large as that produced by industry. It's a sum because the industrial production data is well developed and not dependent on measuring Mauna Loa, and the other calculations are straightforward as well, so there's no confusion of what's a total produced (with my limitations as shown) and what's reported by measurement at 13000 feet.

4. Nor is it to be fobbed off as just part of the carbon cycle...ALL carbon comes from other carbon...but if the CO2 is being ascribed a causative action (a la Anthropogenic Global Warming theory by IPCC), then ALL the sources need to be accounted for, not just some summary presumption (I say presumptuous, tendentious, presumption), if for no other reason than to modify any so-called "forcing" effect, which if it operates at all, does not do so only in response to industrial CO2.

See the video. Ask questions there or here as you see fit. Just one more thing. [snip] I am not the first person on this thread to doubt some (or all) of the not-so-skeptical-science of the blog, but I see that they have disregarded those comments and not changed a thing. Is it characteristic of "skeptics" to be hardened in their skepticism, or is it that they call themselves skeptics as a false-flag clickbait hewing to the AGW belief system? FWIW, I will be keeping a copy of this post in my file in the (unlikely) event that it somehow violates the Comments Policy, by its contradiction of skepsci's assertions.

Moderator Response:

[RH] I would suggest that you re-read the comments policy. Pre-complaining about moderation is still a moderation complaint.

This issue has been thoroughly addressed and you're not adding any new relevant material. The carbon you exhale comes from carbon in the current active carbon cycle. It's not adding any new carbon to the carbon cycle.

When we burn fossil fuels we are extracting ancient sequestered carbon from the earth's geology and, through combustion, are reintroducing that carbon to the modern carbon cycle.

This is a very simple concept which is accepted across the board. For you to dispute it clearly puts you outside of any rational scientific debate.

fishfear at 08:14 AM on 12 April 2017

Heartland: What's your story?

I was going to list dozens of things that would indicate to a curious person that something isn't right but I'm sure my comment would be deleted so why bother.

I have a BS in Physical Science paid for by your tax dollars. I also have a MBA paid for my your tax dollars.

I'm a global warming agnostic... Meaning I agree with the data but not the cause and I choose to think the problem is far from being solved as it's much more complicated than we pretend it is.

So you feel the title of this book is a lie?

I propose that your website is also misleading. You are not skeptical as it's clear you and the folks here absolutely know the ocean level increase and temperature increase since 1900 is directly correlated to the increase in CO2 even though man's contribution didn't kick in until the 1950's.

I don't and thus I'm a denier.

I'm told I can't read data correctly.

I'm told by NASA their own chart that shows more ice growth over nearly all of Antarctica is actually showing melt.

When raw data and methods are not made public even when funded by the government I wonder.

Stay skeptical!

PS The 100 ppm increase in atmospheric CO2 is nothing. However that's a 33% increase for plants which is massive. NASA has been documenting the greening of the world from space. More plant growth, more water vapor, more heating?

Moderator Response:

[JH] Sloganeering deleted.

Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter.

Kiwiiano at 07:39 AM on 12 April 2017

Heartland: What's your story?

Anyone who has watched a courtroom drama on TV is familiar with consilience even if not the word. "His fingerprints were on the murder weapon, me lud, plus the victim's blood on his jacket, he's clearly visible on the security camera and he will inherit $1,000,000 from the victim's will." Convergence of evidence from multiple sources.

Kiwiiano at 07:33 AM on 12 April 2017

Heartland: What's your story?

Any chance of a larger copy of the COMET chart, it's not accessible to we lesser mortals?

nigelj at 06:46 AM on 12 April 2017

Heartland: What's your story?

One Planet has a point. If you were to just start using the word consilience, in a popular public forum, most people wouldn't know what it meant.You would have to define what it meant, especially in relation to climate.

That's ok though, because it applies to all sorts of other things and illustrates a more general point. It's a worthwhile word to learn.

curiousd at 05:58 AM on 12 April 2017

Science of Climate Change online class starting next week on Coursera

O.K...but think that in correction number one I used the unscreened output of the 1500 to 2200 wn band. I think that this does not represent the actual output if water vapor is included. Also recall that in correction number one the output is for 255 K.

Using the SpectralCalc black body calculator set at 0.98 emissivity one obtains:

The unscreened output is 19.35 watts per meter squared for a temperature of 288.2 K for a band from 1500 wn to 2200 wn.

For a band from 1500 wn to 1850 the unscreened output is 14.752 watts per meter squared.

The band from 2 wn to 100 wn produces an unscreened output of 2.02 watts per meter squared.

(a) Total corrected (unscreened by water vapor) flux is then for 2 wn to 1850 wn

260.2 + 14.752 + 2.02 = 276.9 watts per meter squared.

(b) Total corrected flux (unscreened by water vapor) for 2 wn to 2200 wn band is then

260.2 + 19.35 + 2.02 = 281.57 watts per meter squared.

The second total is too large. If I replace the 260.2 watts per meter squared by your 265.9 watts per meter squared then (a) becomes 282.672 watts per meter squared and (b) becomes 287.27 watts per meter squared and now both (a) and (b) are too large.

The question of adjusting from the 1976 Standard atmosphere is one thing, and I'd want to learn more about this. Looks interesting. What is most clear, in my opinion, is that this correction cannot be carried out without putting the water vapor in there. For another thing one wonders: If the piece from 1850 wn to 2200 wn adds so much flux, how could Chen et al just eave it out?

This is all interesting and I appreciate your input and comments.

There is now a practical Skeptical Science question I have....A long time ago I knew of the way to make graphs and paste them into these comments, but now Ihave totally forgotton. I will ask in the Newbie section probably Tom Curtis to once more educate me on this.

uncletimrob at 05:07 AM on 12 April 2017

Heartland: What's your story?

I'm not intending to insult High School general science teachers as I've been one myself - although my prefered subjects are Maths and Physics - but perhaps consilience needs to be use more often in the science narrative in schools? Just a thought.....

uncletimrob at 04:57 AM on 12 April 2017

From the eMail Bag: A Deep Dive Into Polar Ice Cores

Thankyou! I had wondered about the resolution of ice core records, but having no expertise in that area, this article has cleared up most of my questions.

bjchip at 04:34 AM on 12 April 2017

Heartland: What's your story?

12:@onePlanet - I don't think there is much chance of "consilience" being misunderstood. As words go it is pretty unambiguous and more to the point, for the talking heads the need to look it up (in secret) may well surprise them (how many of us are still learning new words?) and the point more clear as a result. I have never, ever, had any backscatter from it, not from denialists, not from anyone.

Denialists can only ignore it (so far that is all they do).

The point I am making however, is not for the denialists. It is for the news readers and news reporters (assuming that there are still some people paid to gather and verify news... somewhere). People who are attempting to achieve "balance" without real knowledge. People who shape the information flowing from the American media.

Convince them, and let them use words that ordinary folks understand. We use the word in interviews and media encounters. That forces the pace for the media. They are obligated by their profession to at least try to be competent in their native language. Not something they can ignore and not something they will misunderstand.

To use it with the masses? Maybe you'd be right about that "elitist" stuff but I would not expect even that. It is an ordinary word that is not commonly used, not a Scientific term. For people so far gone as that, there is no hope as they would rather die than change their minds. The objective is not to let them decide what the rest of us will do.

THAT takes a reduction of ignorance in the electorate in general. Which takes the media and the schools. Only an informed electorate is going to UN-elect Lamar Smith and the T-rump. I've seen this word work for me and I think that in the main, it will do a good job... on my intended targets :-)

As for the brevity and punch-drunk, that'd be facebook and the twits. A form of self-induced attention-deficit-disorder. Zuckerberg created a monster to eat the brains of a generation. Getting careful analysis into a Facebook post is torture. As a result there are children I know who cannot at 18 years, tell me what an analysis is or perform one. They can have opinions though... that's all facebook provides for.

I don't think this story ends well. I will keep trying until my last breath, but I don't expect to succeed.

One Planet Only Forever at 02:32 AM on 12 April 2017

Heartland: What's your story?

Regarding Consilience. Use of a term that:

may need to be looked up
could be misunderstood
can be open to interpretation (and misinterpretation)
may lead a reader to be dismissive of the information being presented because it is "Elitist" or "From an Expert" (examples of terms that should never have developed negative connotations but now clearly are negative in the minds of many people due to the unethical PR successes of "Smart People" like Nigel Farage, Boris Johnson and the many members of Team Trump)

may not be as helpful as using more words to make a point.

The growing predilection with brevity and punchy unjustified, and even totally irrational, info-bites Winning popular support has developed many damaging consequences. An example is the popularity of America First, even though the majority of actions that have been taken and could be defended as being America First, such as the reversal of USA actions to reduce the production of additional CO2, are clearly contrary to improving the future for humanity.

ubrew12 at 01:51 AM on 12 April 2017

Heartland: What's your story?

You make an important point: In a debate, we expect troll behavior, meme's waiting in ambush to trip up the conversation ("Earth is old and climate cycles naturally!"). But our schoolchildren deserve more than knowing what isn't driving their modern climate. As in all things, they deserve our best explanation. It's why we send them to school. Judge Heartland "Heartless" on this one.

MA Rodger at 01:25 AM on 12 April 2017

Science of Climate Change online class starting next week on Coursera

Curiousd @19.
While we have now both sourced Pierrehumbert, are now looking at the same writing, and while you do say “I think we should get this straight before talking about the other issues“, do note my apprehension expressed @18 concerning the use of the 1976 US Std Atmosphere as a global average.

In producing a better global average than the single values fo single the 1976 US Std Atmosphere, the UoC model does provide regional/seasonal alternatives for analysis. I have endeavoured to gain a global average by weighting these regional/seasonal UoC alternatives. Using the surface temperature outputs from the UoC model, the weighting that provided a parity of global average temperature is 50% tropics and 12½% for the 4 remaining latitude/seasons. This is not an unreasonable outcome. It would fit with global coverage 70ºS to 70ºN. (The Chen et al analysis coverage is 80ºS to 80ºN.)
The calculated TOA IR flux from the UoC model when weighted in this manner yield a global average global of 265.9Wm^-2, a significant increase on the 1976 US Std Atm output. If the 1½% to 2% is added to this sum (representing the additional IR in the 0-1800cm^-1 band used by Chen et al but excluded by the UoC model (your 'Correction Number One'), we arrive at a TOA IR flux range of 270-271Wm^-2. These values are now very close to the measured global value used by Chen et al (273.7Wm^-2) and their calculated values (271.7, 274.2, 277.0Wm^-2) . That the UoC calculator comes so close is pretty impressive for a webpage-calculator.

curiousd at 23:47 PM on 11 April 2017

Science of Climate Change online class starting next week on Coursera

Hi M A Rodger,

Look at http://cips.berkeley.edu/events/rocky-planets-class09/ClimateVol1.pdf

Unfortunately the thorough discussion of the various angles one might use under different circumstances on page 191 in my text does not appear to be in this. However, page 190 does have the statement after equation 4.69 "For strong lines the equivalent width is...." Note that within the radical is the symbol L sub S for the "strong path". Note that in equation 4.67 the set of terms q(p)/ g cos theta appear together. The q(p) is not a constant as it is for CO2 up to 100 km, but if I multiply by 1.7 the factor 1.7 being constant comes outside the integral. This complication does not come about for the CO2 case since q is constant and comes outside the integral.

I am assuming that SpectralCalc correctly takes care of the integral of q(p)dp between pressures.

BTW..One of the limitations of both MILA and Spectral Calc is that both have no ability for the user to resolve altitude steps less than 1 km. Of course, both MILA and SpectralCalc have a length resolution much less than this in the underlying program. For MILA I think I recall from the button for the underlying program that the length resolution is one centimeter. MILA is free, SpectralCalc is amazingly reasonable and Modtran6, which I have also purchased is expensive! But with Modtran six, one has a resolution in length at least down to a meter, a wavenumber range way more than I would ever need, and it deals with scattering. But although I am quite familiar with SpectralCalc I can now only do rudementary things with Modtran6, just because I have not studied the program very much. It is breaking in a new GUI interface, other wise I never would have purchased this package.

jgnfld at 23:30 PM on 11 April 2017

Sea ice falls to record lows in both the Arctic and Antarctic

My bad.

Extrapolation is _always_ suspect, true. but at least interpolation in this case can likely be attributed to observable temp/weather changes.

curiousd at 22:47 PM on 11 April 2017

Science of Climate Change online class starting next week on Coursera

Hi M A Rodger,

The reference is my well worn copy of "Principles of Planetary Science" ,Raymond T. Pierrehumbert, Cambridge University Press, third 2014 printing, ISBN 978 - 0 - 521 - 86556 - 2 Hardback. Some time ago in a completely different context I was given an URL for a free online copy by someone on SS. Maybe Tom Curtis??? Even then there is a strange thing...almost all of the ONLINE version is the same as the book, but some of the book material has been left out. Maybe I can dig up the URL to the on line version someplace on my computers, but no guarantees.

MA Rodger at 20:20 PM on 11 April 2017

Science of Climate Change online class starting next week on Coursera

curiousd @19.

It seems we discuss a work by Pierrehumbert. It would be good to be sure we are discussing the same work so a proper reference would be good. The work you reference should be listed here although likely it will be this work you offer up for discussion. (By the way, my initial thought @14 had been solely to provide the links, not to comment on them.)

curiousd at 11:26 AM on 11 April 2017

Science of Climate Change online class starting next week on Coursera

As I said, increasing the water vapor concentration by 1.7 is only because it has precisely the same effect on the radiation emitted as using a 54 degree angled path, even though I am using a vertical path. This is because 1 / cos 54 degrees is 1.7/cos zero degrees. The angle 54 degrees is by some measures, close to the optimum angle to do this.

Here is another way of looking at it. Consider the equation for a "path" such as in equation 4.67 in Pierrehumbert for the strong line limit in the Curtis-Godsen Approximation. There is a factor in the equation for the "path" L_S which is q(p)/cos theta. The q(p) refers to the specific mass as a function of pressure. The equivalent width of a Lorenzian line is given by W = 2 x sqrroot (S(Tnought)*gamma (p0))* times L_S where L_S is the "strong path" (Pierrehumbert top of page 230.) Gamma (p0) is the line width at surface atmospheric pressure. S(Tnought) is the Line Strength analagous to a mass absorption coefficient at the surface of the Earth, where in this approximation one neglects the temperature dependance of the Line Strength. This is all part of an old way to estimate transmittance values without cranking out a line by line result. q(p) is a specific mass which may vary with height ; therefore pressure. Thus, it is a constant for CO2 up to order 100 km; however, water vapor is concentrated near the Earth surface. But no matter; a vertical path (cos zero = 1) ; using 1.7 times q(P)) is mathematically exactly the same as q(P) in the numerator and cos 54 degrees in the denominator. Now that we have SpectralCalc to hand us transmittance values on a platter, it is much easier and quicker to merely multiply the q(P) by 1.7 instead of actually changing to an angled path.

The chief technical person for "SpectralCalc" has told me that the same issue comes up in their radiance programs as in old ways of computing transmittance. Using a 54 degree angled path whilst multiplying the quantity with units of (watts / square meter steradian wave number) by pi is a" quick and dirty approximate way" of converting to diffuse upward flux by averaging over all angles.

The SpectralCalc expert has told me that the SpectralCalc way is to use a "fourth order quadrature" but what I do is a "quick and dirty way to proceed."

Bottom line..what MILA does is to angle integrate all angles and do it correctly. I do not know how to do this, so I use the old recipe for converting intensity to OLR by multiplying by p1 and effectively using a 54 degree straight line path.

(This is sometimes called the "diffusivity approximation" see Science of Doom under greenhouse effect, part 6 the equations , or page 171 in Grant Petty's text book for a drawing of the method. Also see in Liou, p. 127. Liou states that "in general a four point Gaussian quadrature will give accurate results for integration over the zenith angle"..but "for many atmospheric applications it suffices to use (shows equation involving the diffusivity factor.) See Pierrehumbert on page 191 who describes the method at length and even compares the various angles one might use.

Note that 400 ppm x 1.7 is 680 ppm. In my post 9 above you will note that for CO2 if I use a factor of 1.7 to multiply the 400 ppm present day CO2 concentration but do not integrate over angles then I get good agreement with MILA for 400 ppm where they do integrate over angles.

I think we should get this straight before talking about the other issues.

chriskoz at 11:15 AM on 11 April 2017

Heartland: What's your story?

For those who haven't read it or forgotten, it's worth to refresh one's mind by looking at CC Cluedo post to appreciate the extent of consilience in the science of climate change/AGW attribution. Especially the evidence matrix at the bottom.

Any comparison to the contrarian "arguments" by Heartland simply does not exist: any Heartland talk is just silly noise.

John Hartz at 09:35 AM on 11 April 2017

Heartland: What's your story?

Consilience is a very good word. Unfortunately, it is also "science-speak" and therefore it isn't a particularly good word to use in communicating climate science to the average person.

chriskoz at 08:55 AM on 11 April 2017

2017 SkS Weekly Climate Change & Global Warming Digest #14

ThanksTom for that video. Michelle is a very prolific talker, as for a scientist :)

The most remarkable is her admission in the last minute of the video: those deniers who invited her to talk on camera dsid first "probe" her what she would say on the subject of the show and then, when herr point did not suit their opinion, they simply did ask a different question on air: simply did not allow her to talk...

Tadaaa at 08:17 AM on 11 April 2017

Heartland: What's your story?

@ bigchip

to reinforce JH's point i even know, without looking it is an article by Micheal Shermer

conversly i can guess with a high degree of acuracy a denier link to science, just from the URL

it is usually the Zwally antartic study, or the recent "greening" study

nigelj at 08:10 AM on 11 April 2017

Heartland: What's your story?

Consilience is a good word. Everything points at fossil fuels causing a greenhouse effect, from many lines of evidence and different fields of enquiry. If it walks like a duck, and quacks like a duck, it probably is a duck.

Natural causes for the recent warming period have been exhaustively investigated, and ruled out. Every possible idea has been suggested, and evaluated (and this is a good thing). It seems very improbable that we have missed some natural cause.

We are 95% sure we are causing climate change, yet many don't take the problem seriously. This doesn't make sense, because with anything else 95% proof would be sufficient. If some local government authority said they are 95% sure the local river is polluted by bacteria from cows, I think most people would accept this as compelling enough, especially when the evidence is explained.

Of course theres a particularly ruthless campaign to spread doubt about the climate science.

Our other main problem is politicians captive to fossil fuel, business, and ideologically motivated lobby groups. You have to get this out of politics somehow, and tax payer funded election campaigns is one option. At the very least, make activities of lobby groups, funding sources, and donations to election campaigns very public and transparent, so the public can see what influence is operating.

bjchip at 07:28 AM on 11 April 2017

Heartland: What's your story?

Oy! A forceful placement of climate change - Interesting form that slip takes though, taking a chance.

bjchip at 07:25 AM on 11 April 2017

Heartland: What's your story?

Thanks Sarah and I am pretty sure most people here know it. The mainstream media needs to hear it. I expect that more than half the talking heads will be forced to look it up.

:-(

A forceful placement of climate chance as a "Theory" well substantiated and co-equal to other established and accepted theories (eg. Evolution) can cancel much of the noise being injected by the denialsphere.

Sarah at 07:09 AM on 11 April 2017

Heartland: What's your story?

Consilience is indeed an excellent term for the agreement among multiple streams of evidence for climate change.

We should use that word more often; it's a feature notably lacking in alt-theories of climate.

MA Rodger at 04:51 AM on 11 April 2017

Science of Climate Change online class starting next week on Coursera

curiousd @15,
I should confess that my comment @14 was quite a bit more than I had initially intended to say, and I can see I have erred in places (but only in places).

Concerning your "Correction Number One", the value presented by the UoC calculator as 'Upward IR Heat Flux' is calculated over the range 100cm^-1 to 1500cm^-1 and I think we can say with confidence that such a restricted spectrum will be ignoring 3.6% of 255K blackbody radiation spectrum. Of course, the TOA spectrum is only a very very approximate blackbody spectrum. I did a very quick scaling of this graph which plots TOA flux from 0cm^-1 to 2000cm^-1 and suggests there is somewhat less than 3.6% unaccounted, perhaps only a further 2% in the 0cm^-1 to 2000cm^-1 range leaving potentially 0.5% of unaccounted blackbody radiation above 2000cm^-1.

It seems I was in error interpreting what your "Correction Number Two" was about. On reflection, your second correction appears to be suggesting that MODTRAN does not correct for the horizontal component of radiative transfer. This I cannot believe. And I fail to grasp the logic of your correction - increasing water vapour by a factor of 1.7 (=1/cos54º, the angle being the average for the integral). If such a correction were to be made, surely it would also require a similar adjustment to all other GHGs.

Chen et al (2013) does indeed concern clear-sky data (specifically 2004 data) and thus is comparable with 'No Clouds or Rain.' Note that Chen et al compares observations with reanalyses which use MODTRAN5 to calculate the TOA spectra flux. The comparisons of flux over the spectrum 0 – 1800 cm^-1 are scattered either side of the observation with roughly 1% accuracy. This result suggests that MODTRAN in an apples-v-apples analysis does not need correction. The use of the 0 – 1800 cm^-1 spectrum also reduces the blackbody IR beyond the range 100cm^-1 to 1500cm^-1 to 2.8% and scaling that graph of TOA IR it reduces to 1.4%.
Concerning the use of 1976 US Std Atmosphere. This is a global average for the full annual cycle and with non-liner calculations such an average cannot be as acccurate as the Chen et al analysis. If the impact of using a spectrum 100cm^-1 to 1500cm^-1 is roughly 2%, a little under half of the descrepancy you set out @10, it may be worth considering if a less crude averaging method can be shown to reduce that remaining 3%.

There may still be other explanations. It is not impossible to believe that the UoC calculator contains simplifications (as yet undiscovered by us) even though it produces some very convincing-looking outputs.

John Hartz at 04:35 AM on 11 April 2017

Heartland: What's your story?

To get a basic understanding of what climate models are, check out this recently posted article...

Yes, we can do ‘sound’ climate science even though it’s projecting the future by Kevin Trenberth & Reto Knutti, Conversation US, Apr 5, 2017

Note: Trenberth & Knutti recommend using the word projection (rather than predicition) to describe the output of climate models.

DaveMartsolf at 03:40 AM on 11 April 2017

We're heading into an ice age

Deep thank yous to Yail Bloor, Tom Curtis, and scaddenp. Together you have cleared up all my questions regarding the interrelated processes that are bringing out an unfortunate future to our planet. I totally understand now why current and near future increased levels of CO2 will be around for centuries. And, scaddenp's link to Howard Lee's article describing an outcome of rapid CO2 increase that I did not think possible. I can understand why these facts have not been made into a movie, although they should be. I want to thank all of you for opening my eyes and for filling in all the blanks in my understanding. May our future generations find a way to survive The Once and Future Planet.

bjchip at 03:21 AM on 11 April 2017

Heartland: What's your story?

The word that nobody seems to know is

"consilience"

...and it is what makes the climate change theory an established theory, much like evolution, not a hypothesis.

https://www.scientificamerican.com/article/why-climate-skeptics-are-wrong/

Moderator Response:

[JH] Rest assurred that the SkS author team and most of our regular readers know the meaning of the word consilience.

John Hartz at 03:05 AM on 11 April 2017

Heartland: What's your story?