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broadbarrel at 13:58 PM on 16 April 2017Debunking Climate Myths from Politicians
Skeptical Science Please add Scott Pruit to the politicians list. Pruitt was quoted as saying: “The American people are tired of seeing billions of dollars drained from our economy due to unnecessary EPA regulations, and I intend to run this agency in a way that fosters both responsible protection of the environment and freedom for American businesses.” Quote is from url: https://www.washingtonpost.com/news/energy-environment/wp/2016/12/07/trump-names-scott-pruitt-oklahoma-attorney-general-suing-epa-on-climate-change-to-head-the-epa/?tid=a_inl&utm_term=.254fc501733e
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broadbarrel at 13:56 PM on 16 April 2017Debunking Climate Myths from Politicians
Skeptical Science, Please at President Donald Trump to the list of politicians. “For too long, the Environmental Protection Agency has spent taxpayer dollars on an out-of-control anti-energy agenda that has destroyed millions of jobs, while also undermining our incredible farmers and many other businesses and industries at every turn,” This has been quoted from url: https://www.washingtonpost.com/news/energy-environment/wp/2016/12/07/trump-names-scott-pruitt-oklahoma-attorney-general-suing-epa-on-climate-change-to-head-the-epa/?tid=a_inl&utm_term=.254fc501733e
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Haze at 10:47 AM on 16 April 2017New study shows worrisome signs for Greenland ice
This piece commences "As humans put more heat-trapping gases into the atmosphere, like carbon dioxide, ice around the planet melts. This melting can be a problem, particularly if the melting ice starts its life on land." In view of this it is surprising that a recently published paper claims the Antarctic Peninsula is cooling. This paper (Oliva, M., et al., Recent regional climate cooling on the Antarctic Peninsula and associated impacts on the cryosphere, Sci Total Environ (2016), http://dx.doi.org/10.1016/j.scitotenv.2016.12.030) states "from 1998 onward, a turning point has been observed in the evolution of mean annual air temperatures across the Antarctic Peninsula region, changing from a warming to a cooling trend,". This is not an isolated observation as others (Carrasco, J.F. 2013. Decadal changes in the near-surface air temperature in the western side of the Antarctic Peninsula. Atmospheric and Climate Sciences 3: 275-281). and Turner, J., et al 2016. Absence of 21st century warming on Antarctic Peninsula consistent with natural variability. Nature 535: 18645.} have also shown a decline in Antarctic Peninsula temperatures. Warming in the Antarctic has been claimed to be due to atmospheric C02 but it now seems that CO2 may in fact cause cooling in the Antarctic Peninsula (Holger Schmithusen, Justus Notholt, Gerd Konig-Langlo, Peter Lemke, Thomas Jung. How increasing CO2 leads to an increased negative greenhouse effect in Antarctica. Geophysical Research Letters, in press, 2015. doi: 10.1002/2015GL066749.)
Moderator Response:[DB] Please keep your comments on-topic to the OP of the thread.
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chriskoz at 07:58 AM on 16 April 2017New study shows worrisome signs for Greenland ice
Anyone studied the flood frequency in Greenland? The 2012 one in Kanger was well publicised but I think we are dealing with substantial increase here rather thana one in a century event like 2012 with unprecedented surface melt.
I think all infrastructure there maybe at risk of distuction by exponentially increasing flood frequency. So to those silly statements claiming some parts of the world would benefit from warming, in particular "Greenland will become greener" I would say: ain't necessarily so. "Greening" will not happen when country is about to be ravaged by serious floods. But I don't have any data confirming my fears over future of Greenland population. Obviously their culture - the disappearance of glaciers they admire and worship - is undisputable here. But on top of that their very existence maybe at stake. Will they adapt to more frequent flooding?
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joe - at 04:07 AM on 16 April 20172017 SkS Weekly Climate Change & Global Warming News Roundup #15
Just weeks after a high court in the Indian state of Uttarakhand granted legal personhood to the Ganges and Yamuna rivers.
An Indian court says glaciers and rivers are 'living entities.' Could the same approach work in the US?
Could this same approach work in the United States - such a holding in a US court would be in direct conflict in Roe V Wade where a personhood doesnt exist until emergence from the womb.
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MA Rodger at 22:00 PM on 15 April 2017Science of Climate Change online class starting next week on Coursera
curiousd @24,
To recap my postion on your "Correction Number One" which concerns an underestimation by UoC MODTRAN model (aka MILA) of TOA IR flux due to the limits of the wavelength used in the UoC model.
@7 you calculated a potential value of this correction as 9W/sq m, roughly 3.6% of the UoC calculated average global value.
@18 I argue that this value is too high, presenting two reasons for my lower estimate of roughly 2% or 5W/sq m.
@24 you are now calculating the value for this "Correction Number One" as if the extented spectrum (beyond that used in the UoC calculation) has zero GHG acting in it. The value you calculate 14W/sq m is thus a maximum value for "Correction Number One" which would be valid only for a zero or very small GHG effect in the wavelenghts being considered. As the graph I linked @18 shows, there is a large GHG effect in these wavelengths and the large correction you suggest @24 is unjustified.
curiousd @26,
You state that your "Correction Number Two" has been discussed with me up-thread. My position concerning the existence of your "Correction Number Two" remains as stated @18 - "This I cannot believe. And I fail to grasp the logic of your correction." Our discussion has not developed beyond that point (other than sorting out some references).
Concerning your "Correction Number Three," I fail to see the origins of the "One km" IR Radiance values in the graph linked @25. The "Surface" values are evidently blackbody calculations which are thus much dependent on emissivity. Indicative of the emissivity value (E) is the Peak Spectral Radiance (PSR) which for a blackbody temperature of 288.2K would be:-
E/PSR, 0.92/0.125, 0.94/0.128, 0.96/0.131, 098/0.133, 1.00/0.136.
Examination of the UoC output file for 1976 US Std Atmosphere (288.2K) yields a maximum PSR of 0.133 W/sqm/sr/cm^-1 which indicates Emissivity = 0.98. The Band Radiance from the UoC calculations (43.589 W/sqm/sr for 500-800cm^-1) also suggests Emissivity = 0.98.
It is unclear to me how you are calculating the 1km Band Radiance values. (You give the Emissivity = 0.98 value for 1km as 42.7272 W/sqm/sr which I note is very similar to the UoC value for Band Radiance 490-860cm^-1 42.756.) It is also unclear why this would indicate an Emissivity of 0.92.
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curiousd at 18:53 PM on 15 April 2017Science of Climate Change online class starting next week on Coursera
Also, regarding to explaining correction three, the following comparison might be useful.
Modtran Light in the Atm SpectralCalc Modtran6
PRICE free $ $$$$
dist resolution 1 km 1 km < 1 meter
maximum alt up to 70 km error message if TOA
>"1 million point error" exceeded
if too much band width
or altitude. Therefore simulating a 54 degree angled path by multiplying the input concentration can be possible whilst extending path length not so much
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curiousd at 08:51 AM on 15 April 2017Science of Climate Change online class starting next week on Coursera
Refer to the image you get from post 25 above. For a CO2 only GHG atmosphere these are plots of the in band outgoing radiance, in w/meter sqd steradian, for wave number range 500 wn to 850 wn CO2 bending mode, versus Earth Surface thermal IR emissivity looking down from zero km and from 1 km. I use a 680 ppm CO2 concentration because this is the present day concentration of 400 ppm multiplied by 1/cos 54 degrees, and 1/cos 54 degrees is 1.7 . Therefore a vertical path with 680 ppm has the same optical length as 400 ppm at a 54 degrees angle relative to Nadir. Therefore I can use this application of the "diffusivity approximation" as a decent substitute for actually integrating over all angles when I multiply by pi streadians to obtain out going flux in W/meter squared. This has been discussed previously by myself and M.A. Rodger here. See posts above 9 and 24.
Of interest here is the sign of the difference between the 0 km and 1 km output. This difference is, for the MILA emissivity of 0.98, given in post 9 and is for the OLR where multiplication by pi steradians has been carried out, equal to 360.2 w/meter square minus 357.5 w/meter squared. Then the OLR at 1 km is about 2.7 watts per meter squared less than at zero km.
In the figure for the URL given above, the multiplication by pi steradians has not yet been carried out and for emissivity of 0.98, the surface upward in band radiance exceeds that of the same quantity at 1 km by 43.5764 minus 42.7272 or 0.8492 watts /meter squared steradian. Multiply this quantity by pi steradians to obtain a result which is 0.8492 times pi and rounds off to 2.7 watts per meter squared, in agreement with post 9 above.
However, note in my figure you can see at the URL I refer to above, the value of the one km in band radiance decreases at a rate less than that of the zero km in band radiance as the emissivity is decreased. In fact, for surface emissivities of 0.93 or less the upward in band radiance at 1 km is greater than the upward in band radiance from the surface.
I was surprised at this result, but it has to do with Correction Three since the sign of the difference between OLR surface and OLR 1 km changes sign between emissivity of 0.98 and 0.92.
The "apparent " emissivity of MILA obtained just by looking at the output without knowing the settings of the underlying program or knowing about the 100 wn to1500wn truncation, is not 0.98 but 0.92.
This can lead astray anyone wishing to check if they are using Schwarzchild's equation correctly to compute the CO2 outgoing flux, by usig MILA. And where else can the user find a set of OLR values such a at MILA to test if she/he is doing things correctly?
I will let this post "subilate" a bit before proceeding. The finding that one can have OLR at 1 km greater than at zero km seems surprising, and my only justification so far is that: 1. I use a procedure with SpectralCalc that give good agreemen with MILA and gives an expected CO2 climate sensitivity of ~ 4 watts/meter squared. 2. That applying that procedure to low emissivities of 0.93,0.92,0.91, 0.9, and 0.89, gived me the result that the OLR from 1 km exceeds that from the surface.
I believe that desert aras have such low emissivities.
Of course an emissivity in the thermal IR less than one implies some scattering or reflection, so that likely must be considered. BTW SpectralCalc gives the caveat that they do not deal with scattering in any way; just absorption and emission.
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Philippe Chantreau at 08:11 AM on 15 April 2017Breathing contributes to CO2 buildup
I understand the idea Tom. You expand quite well on what I described a little too quick as "shuffling carbon around." My opinion is that the kind of biomass change that would be required to explain the past 100 years increase in atmospheric carbon is so immense as to preclude a major role in this change, especially while the oceans are still acting as a sink. The idea that all of the increase could be due to biomass changes is simply not believable.
Perhaps Dr Bill is trying to make the argument that the biomass contribution is underestimated, although the bulk of what he said was innuendo on IPCC intentionally skewing the issue, which was unwarranted, as you showed. My understanding is that there is quite a bit of litterature on the subject and that the range of possible contribution of biomass changes is fairly well constrained. I don't see at first glance that Dr Bill has anything revolutionary to overturn the current state of knowledge on the subject.
www.epa.gov/ghgemissions/global-greenhouse-gas-emissions-data
Intesresting discussion here:
www.newscientist.com/article/dn11638-climate-myths-human-co2-emissions-are-too-tiny-to-matter/
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curiousd at 07:48 AM on 15 April 2017Science of Climate Change online class starting next week on Coursera
http://IMGUR.com/a/UMUR1
Please highlight, right click,and go to the URL. I could not get the image to load directly. Sorry.
This image has to do with the last correction,"Correction Three" to MILA
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Rob Honeycutt at 04:52 AM on 15 April 2017Breathing contributes to CO2 buildup
Here's a video from NASA on this topic.
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David Kirtley at 11:24 AM on 14 April 2017From the eMail Bag: A Deep Dive Into Polar Ice Cores
Great questions, chriskoz. I'll have to try to dig up some answers. I skimmed the paper which had the Delta-ages graph: WAIS Divide Project Members (2015) as well as Bender et al. (2006) but I need to read them more closely. Another paper I found and skimmed also looks promising: Buizert et al (2015) The WAIS Divide deep ice core WD2014 chronology
Sorry to just throw papers at you but at the moment, and for the next 3-4 days, I won't have any time to dig any further. But I wanted to give you something in case you want to do some digging yourself.
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Tom Curtis at 10:41 AM on 14 April 2017Breathing contributes to CO2 buildup
Imagine a model system in which plants are grown in a sealed, airtight compartment. Suppose conditions are such that the growth of the plants is limited only by energy input (ie, sunlight). As the plants grow we feed in CO2 until the plants are mature. We then seal the system so that any further growth of plants can only be achieved by reducing CO2 concentration within the model system. After a period of time an equilibrium concentration of CO2 will be achieved. Plant growth will be CO2 limited, in that addition of further CO2 to the system would allow an increase in plant biomass within the system, but as CO2 was fed in until the plants were near maturity, the CO2 limit on further growth will not be much below the energy limit on further growth.
What happens when we introduce a small population of herbivores, predators, and such other organisms so as to allow a stable ecology in to the system?
The obvious first effect is that plant biomass will be reduced, and replaced by animal biomass.
However, there will not be a one-for-one replacement of animal biomass for plant biomass. That is because of the energy pyramid. As you proceed up the trophic levels, from plant to herbivore, from herbivore to carnivore etc, each level converts energy to biomass with an efficiency of about 10%. As an example, suppose in our model system, equilibrium is reached when the herbivores reduce total plant biomass by 10%. Then of the energy stored in that plant biomass, only about 10% will be converted to herbivore biomass. Similarly, only about 10% of the energy storage of herbivore biomass consumed will be turned into carnivore biomass. Consequently the total biomass in the model system will be reduced.
The difference between the carbon content of the original plant only biomass and the plant plus animal biomass will by stored in other carbon reservoirs. That may be as soil carbon, but due to the processes of animal respiration and decay, some of it will be as an increased CO2 concentration.
This is the mechanism explicitly mentioned by Grumpymel @93, and possibly is the mechanism discussed by DrBill @95. To the extent that it is the mechanism envisioned by DrBill, his claim that increased animal biomass will result in increased atmospheric CO2 is correct, although his calculation of the effect is not necessarilly valid.
Ignoring for simplicity the potential increase in Soil Organic Carbon, and any uptake by standing water, and other carbon compounds, the increase in atmospheric CO2 in our model system will be:
(((Final plant biomass - initial plant biomass) x % of carbon by weight in plant biomass) - ((final animal biomass - initial animal biomass) x % of carbon in animal biomass)) x 44/12
The final factor can be ommitted if you measure the CO2 concentration by mass in units of GtC rather than Gt-CO2.
With regard to the IPCC's treatment of this, the first thing to note is that they do report on the change of Carbon due to the change in plant biomass. Specifically, in IPCC AR5 they report that plant biomass has decreased by 30 +/- 45 GtC. That means that, unless animal biomass has decreased, they have over estimated the total change in biological carbon reservoirs (ignoring the controversial issue of SOC). Further, the total change in animal biomass, which has increased; represents a further reduction in CO2 available for other reservoirs including the atmosphere.
So, if this is what DrBill is drawing attention to, he is right that the mechanism can increase total atmospheric CO2 (by reducing plant biomass); but wrong in assuming it is neglected by the IPCC, who do their best to quantify the positive side of the equation (ie, the loss of plant biomass) even if they neglect the much smaller (by an order of magnitude) negative side from the increase in animal biomass.
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Philippe Chantreau at 09:19 AM on 14 April 2017Breathing contributes to CO2 buildup
Dr Bill, I don't see any clarification with this addition of words. The issue is the physically nonsensical argument that the CO2 from respiration is of a same non-polluting nature as that which is produced by oxydation of fossil fuels previously sequestered in the crust. The implication of Plimer's quote is that some of the atmospheric CO2 we are experiencing is due to animal respiration. You seem to concur with that, without clearly stating it, so far as I can recall.
I see nothing in your contribution here that would actually support this argument. I see no explanation of how animal respiration can cause a net increase in atmospheric CO2, which is the real problem, as I have stated above. I see no possible source for animal generated carbon other than the atmosphere itself, you offer no alternative.
You stated yourself at #100 earlier that "No one said it was a net addition to the carbon budget."
This suggests that you are trying to hypothesize that the atmosphere can go from 300 to 400 ppm in a very short time without a net addition, only by shuffling carbon around (possibly by way of animals) and loosing sinks, while the ocean is still absorbing enormous amounts of it. If so, you must come up with a loss of sink so gigantic that no geological event in the relevant past could foot the bill, certainly not the known land use changes, subject of abundant litterature.
Meanwhile of course, the oxydation of fossil fuels is real and ongoing, regardless of any other hypothesis, as are the isotopic signature changes in the atmosphere and multiple other elements consistent with the net addition of fossil carbon.
I am not thus far enclined to spend any time on your YouTube vids.
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Tom Curtis at 09:05 AM on 14 April 2017Breathing contributes to CO2 buildup
Dr Bill Hoffman @100:
"[T]he equation I showed, Tom, was directly copied from their 2005 Report that I used ..."
The IPCC had only two reports in 2005, that on Carbon Capture and Storage and that on Safeguarding the Ozone Layer. I have skimmed the first of these and found nothing resembling your formula. Nor, obviously is there anything resembling it in the relevant chapter of the 2001 report (the current assessment report in 2005). The formula doesn't appear in the 1995 assessment report (SAR) either, although Table 2 (page 17) could be interpreted as supporting such a formula, however Table 2 is explicitly labeled as "...the anthropogenic carbon budget...", and makes no claim to be a complete carbon budget. With regard to that, it says:
"The estimate of the 1980s' carbon budget (Table 2) remains essentially unchanged from IPCC (1994). While recent data on anthropogenic emissions are available, there are insufficient analyses of the other fluxes to allow an update of this decadal budget to include the early years of the 1990s."
Looking to figure 4 (page 21) of the 1994 report (Radiative forcing of climate change) clearly shows the other fluxes to include global net primary production and respiration. These are also discussed in the First Assessment Report (1990), as can be seen in Figure 1.1 (Page 8).
In short, the formula is not justified by any IPCC report prior to 2006, and certainly in none after it. If you wish to maintain the contrary, you will need a precise citation, ie, the report by full title, together with the page number at which the formula appears.
"I said 40% more, and you want to argue 33%...tomayto tomahto...they found industrial CO2 and stopped accounting"
First, you claimed 50% in the video, not 40%. In otherwords, even at face value you exagerated the effect by 50%. If you think pointing out a 50% exageration is mere quibbling, you are no scientist.
Second, as clearly shown by my review of their literature above, the IPCC since day 1 (First Assessment Report 1990), have included "respiration" which includes respiration by animals and plants, along with the emission of CO2 by decay of organic matter and by fires. Since the fourth assessment report (2007), they have also included volcanic emissions.
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nigelj at 06:33 AM on 14 April 2017Scientists can be advocates and maintain scientific credibility
I think this depends exactly what sort of advocacy you mean. Let's say scientists make impassioned speeches in the media advocating renewable energy. As a lay person I would be comfortable with this to a point. I would expect climate scientists to support renewable energy, it would be very odd if they didn't, so it's probably not going to be a problem if they "ocasionally" advocate this. But too much of this might attract accusations of scientists not doing their main job. It's like anything, a question of balance
It will also work best if it comes from a scientist with a generalist physics degree, who therefore has credibility to talk about energy. It might not work so well coming from a geologist, with all due respect.
If you are talking about advocating for the science, then yes I think absolutely the more of this we see in the media the better. Every climate scientist I have seen doing this advocay in public has impressed me, although of course some are more natural at it than others.
I expect people to stick up for their beliefs and interests. I suspect experts have more credibility with the public, than politicians or lawyers trying to advocate for the science.
I think generally keep advocacy dialogue rational and measured, and don't get bogged down in detail. Having said this, there are times as a lay person I wish climate scientists would just occasionally show a bit of very public anger, at the nonsense we get from the denialists. If this is sparingly done, it has enormous impact.
If you are talking about the anti - science issue dominating America, then I think scientists are absolutely entitled to march in the streets and strongly defend their position. Remember nice, quiet guys get walked over. I think you will get a lot of sympathy from the public. Of course none of us want to waste time marching in the streets, or in public relations, but sometimes it just has to be done.
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DrBill at 06:18 AM on 14 April 2017Breathing contributes to CO2 buildup
RedBaron Sorry, I never made a transcript. I had notes, but never typed them up. I am quite familiar with the summary data of Mauna Loa, thanks.
That said, it is not the summary data that matters in my analysis, and I suspect others have something of that confusion when they "do not understand what point [I'm] trying to make" {Phillippe}. The summary data collects all the CO2 from industry and breathing and all sources, less that which returns to biomass, terrestrial and aquatic, or to the oceans directly. It has many issues of validity, but that's not for here and now.
What is for here and now is that Mauna Loa is like the old flip-chart 'digital' clock, that flipped over once a minute. Real CO2 is the sweep hand of a better clock, counting continuously. The sun does not wait for the report from Mauna Loa, if it does anything, CO2s effect is there all seasons, all times, neither just when the sun's out, nor only when it's summer, nor only when industry is running. It's not that hard to see: the addition of CO2 by vastly accelerated conversion (as fossil fuel) or much slower accelerated conversion (as digestion/respiration) or still slower conversion (simple rot), leads to some measureable level of CO2 on a moment by moment basis, an increase, by the explanation I've given, that seems to cause much consternation. Any decrease, by plant growth or subduction in the sea around Antarctic would do something that made the final totals at monitoring sites change, but until such decrease took place, the CO2 from all sources I've mentioned is still in the air and still doing what CO2 does.
Moreover, it does not matter which process is faster and which slower, since the production rate is the sum of both industrial production and digestion/exhalation, like the sweep second hand (or if the circularity of the sweep overwhelms is graphic value of smooth and unrelenting, consider a pail with a hole in it, being dripped into by two sources (I actually might like that one better myself). At the moment we are not concerned by the drip, or even how full the pail might get, but only in the amount of something inherent in the water that might be able to do some harm. Would it serve to say we've identified the problem because we found a leaking faucet over the pail, while ignoring a smaller leaking faucet? Since the drip keeps the pail from filling up quickly, are we being good pail-monitors to just evaluate the level monthly and deny the smaller faucet?
As an OT, on this thread, I would enjoy finding a thread that addresses the process I have heard called "positive feedback loop". Where might I find it most discussed in terms of its physics? TIA
Moderator Response:[DB] "I would enjoy finding a thread that addresses the process I have heard called "positive feedback loop""
Unlike the simple example of positive feedback we learned in high school, the increase from every round of feedback gets smaller and smaller, in the case of the enhanced greenhouse effect. It is a significant factor in the overall warming, but it does NOT lead to a "runaway" trajectory for temperature.
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Philippe Chantreau at 04:21 AM on 14 April 2017Breathing contributes to CO2 buildup
I still do not understand what point you're trying to make. The net addition of carbon to the atmosphere is the problem, the only problem.
The net increase is the only thing that matters; it is not, and can not physically be caused by animals breathing. They get their carbon from the atmosphere, through organisms that have the ability to absorb it and integrate it in their structure. The bulk of these organisms is made of plants. How is the animal activity going to change the balance? Animals just shift the carbon around in short term small cycles. They do not add carbon to the atmosphere that wasn't taken out of it in the first place, so why does that matter when considering the bigger picture?
Moderator Response:[RH] Go to the link for Bill's video lecture and start about at minute 12:00. In a nutshell, he's attempting to say (not joking here) that the change in atmospheric CO2 levels is due to the increase in human population.
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RedBaron at 04:09 AM on 14 April 2017Breathing contributes to CO2 buildup
@Dr Bill,
Could you please link to a written transcript? The computer I currently have access has no sound. I do like a good lecture, probably more than most, but unfortunately can't currently follow your points until I get to a computer with speakers. I would love to see what this fuss is actually all about.
Regarding your comment above, "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."
That seems to be stating the obvious but in a way that is an attempt to obfuscate.
Of course it matters little the source of the CO2 as to the relative forcing. The source matters when calculating the relative net increase in atmospheric CO2. All fossil fuel CO2 is old carbon added to a roughly balanced system. So even though the biosphere is a self adjusting complex biological system, the quantity of old CO2 being released is greater than the biosphere's capability to adjust currently. The net CO2 concentrations rise. Higher atmospheric CO2 concentrations mean increase solar heat retained in the system. The “greenhouse” effect. The IPCC assessment may not be perfect, but that part they got roughly correct. Rapidly cycling CO2 in the biosphere does not have the same net effect on atmospheric CO2 concentration as slower old cycle carbon that has been out of the system for millions of years.
When it comes to respiration, that only results in a net increase in CO2 levels when the other side of the carbon cycle (photosynthesis) is simultaneously reduced as respiration increases. As long as we are careful not to reduce photosynthesis by destroying ecosystem function, then respiration can’t cause a net increase in atmospheric CO2 levels beyond a very short term peak usually disappearing in a matter of months. It is self limiting. This is what gives the graph a saw tooth pattern.
What gives the graph the smoothed out steady increase is a combination of fossil fuel use and ecosystem degradation, mostly due to agriculture.
If there is a blind spot in the IPCC assessment, it could be in underestimating the impact of agriculture in degrading ecosystem function. This is a case I have made elsewhere on this forum. However, the assessment is certainly correct in ignoring for the most part the short term biosphere cycle of photosynthesis and respiration as roughly canceling each other. There is no net increase in CO2 due to animals breathing. That’s just the natural carbon cycle signal, nothing to do with AGW. -
DrBill at 02:31 AM on 14 April 2017Breathing 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.
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Tom Curtis at 16:50 PM on 13 April 2017Breathing 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.
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Philippe Chantreau at 11:58 AM on 13 April 2017Breathing 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.
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Eclectic at 11:54 AM on 13 April 2017Breathing 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.
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Mal Adapted at 10:23 AM on 13 April 2017Heartland: 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?
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DrBill at 10:11 AM on 13 April 2017Breathing 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.
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chriskoz at 07:23 AM on 13 April 2017From 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?
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Bob Loblaw at 11:10 AM on 12 April 2017Welcome 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...)
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ubrew12 at 10:43 AM on 12 April 2017Heartland: 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.
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curiousd at 10:33 AM on 12 April 2017Welcome 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
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DrBill at 08:51 AM on 12 April 2017Breathing 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.
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fishfear at 08:14 AM on 12 April 2017Heartland: 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 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.
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Kiwiiano at 07:39 AM on 12 April 2017Heartland: 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.
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Kiwiiano at 07:33 AM on 12 April 2017Heartland: What's your story?
Any chance of a larger copy of the COMET chart, it's not accessible to we lesser mortals?
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nigelj at 06:46 AM on 12 April 2017Heartland: 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.
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curiousd at 05:58 AM on 12 April 2017Science 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.
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uncletimrob at 05:07 AM on 12 April 2017Heartland: 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.....
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uncletimrob at 04:57 AM on 12 April 2017From 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.
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bjchip at 04:34 AM on 12 April 2017Heartland: 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.
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One Planet Only Forever at 02:32 AM on 12 April 2017Heartland: 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.
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ubrew12 at 01:51 AM on 12 April 2017Heartland: 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.
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MA Rodger at 01:25 AM on 12 April 2017Science 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 2017Science 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.
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jgnfld at 23:30 PM on 11 April 2017Sea 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.
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curiousd at 22:47 PM on 11 April 2017Science 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.
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MA Rodger at 20:20 PM on 11 April 2017Science 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.)
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curiousd at 11:26 AM on 11 April 2017Science 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" LS 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 LS where LS 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.
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chriskoz at 11:15 AM on 11 April 2017Heartland: 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.
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John Hartz at 09:35 AM on 11 April 2017Heartland: 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.
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chriskoz at 08:55 AM on 11 April 20172017 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...
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Tadaaa at 08:17 AM on 11 April 2017Heartland: 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
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