Professor Galen McKinley at the University of Wisconsin-Madison has recently put up a web page which discusses the global carbon cycle and its connection to climate change. Within, is an applet in which the user can play around with various inputs of carbon sources and sinks, and see how this determines future CO2 concentration and global mean temperature. It might be worth playing around with for a while to see how various future scenarios might look.
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Climate Change 
Thank you. Although, if I understand what I’m looking at, the applet is just adding up all the user-defined sources and sinks, which is a fairly trivial calculation. I was hoping for a second that it’d be an integrated carbon cycle, where the ocean sink is a dependent variable, not an independent one.
This is marvelous. I can have each student setup their own scenario and run it and report on the results and why the projection proceeded as it did.
A web applet?
The CRU emails and code scripts are leaked. New Zealand and Australia both get caught doctoring their land temperature data to invent warming trends the hardware doesn’t see. Michael Mann, after getting caught using the Tiljander sediment data upside down to show warming where there was in fact cooling, publishes a new paper using Tiljander series upside down again as a giant middle finger to Steve McIntyre, and to demonstrate the power the climate peer review mafia has over the peer review process.
Don’t get me wrong, the web applet shows a lot of work even if it does present exact numbers when the feedbacks aren’t known to anything like the accuracy they are pretending. It just seems like talking about the applet when these monumental happenings are going on is like whistling as you walk past the graveyard.
Response– I’d prefer to stick to interesting science. I think enough people have already covered the East Anglia issue (if there was really something interesting to it aside from skeptics taking a handful of sentences dramatically out of context, then maybe I’d be more interested). And quite honestly, your opinions about where climate science has recently gone and the “doctoring of data” is…bizarre.– chris
Cool! Thanks for reporting!
What do you tnink about the temperature scale? I think that stabilisation in 450 ppm still gives a 50 % chances of exceding 2 ºC over pre-industrial levels. However, in the temp scale, 450 ppm matches about 0.6 ºC over current levels, i.e. 1.2 ºC over pre-industrial times. The same with 1000 ppm, for which our best guess is about 5,1 ºC, but in the applet it is about 4,5 ºC. I think that the scale may underestimate temperature change.
*The author warns that “The estimated global temperature response is a rough scaling based upon average IPCC AR4 (2007) model sensitivity to atmospheric CO2. It is for illustrative purposes only.”
You have a great site here Chris. Much good, well explained information that I’ve only just begun to explore. Thanks for your efforts.
On my (very long) to-do list is to build a java program to make a simple, carbon cycle model with user-adjustable parameters in order to explore past and future CO2 concentrations.
If I’m ambitious, I would like to include isotope data so that people can look at the C12/C13 and C14 effects, and maybe O2 data…
Part of the point would be to disprove Essenhigh, show Spencer that his “discovery” that C12/C13 varies interannually is unsurprising because forests and fossil fuels have the same C12/C13 signature. But part of the point would just be to have easy access to a several-box diffusive model for general educational and projection purposes.
And then projections could be compared to the Bern carbon cycle approximation.
-Marcus
(other java program I mean to write someday include one to calculate total radiative forcing and CO2 equivalents from input concentrations – that one is easy, I already have Excel spreadsheets that do it, but it seems to be a common question)
I’m a bit surprised that both the fluxes between the atmosphere and ocean have increased so much (carbon cycle tab on Galen’s website). Anyone know why that is?
Patrick: I note that 20/70 is actually a very similar ratio to 165/597, though I’ll admit that it didn’t look that way to me at first glance. So what we’re seeing is exchange with the oceans increases in approximate proportion to the total atmospheric concentration.
Or did I misunderstand your question?
Marcus (Thank you) – Okay, that makes sense, that the rate of CO2 diffusion across the water surface interface from either side would tend to be proportional to concentration on that side (with caveats about ocean chemistry) –
Gt C increase/ Gt C preindustrial = % increase:
atmosphere
165/597 = 27.6 % increase
flux from atmosphere to ocean
22.2/70 = 31.7 % increase
flux from ocean to atmosphere
20/70.6 = 28.3 % increase
BUT: surface ocean
18/900 = 2 % increase
18/? = 28.3 %
? = 18/0.2833 (using more accurate value of 20/70.6 for calculation) = 63.5
So if the largest possible fraction of the 900 Gt C in the preindustrial ocean that was in the same mix of forms (CO2, H2CO3, HCO3-, CO3–) as the additional 18 Gt C were somewhere around 63.5 Gt, would that make sense?
Bryan, I fully support what you said on 8th. Clmategate is being investigated on both sideof the Atlantic and those file that were leaked are much much more than just QUOTE: a handful of sentences dramatically out of context UNQUOTE as Chris put it.
Chris, in your reply to Bryan you said QUOTE: I’d prefer to stick to interesting science UNQUOTE so here’s a repeat of what I posted on yur “Consequences” thread which you chose to ignore. Was it too hard for you ?
From 30th November on “COnsequences.. “thread.
Chris, here is the abstract from Roger Taguchi’s revised paper. Roger has sent me a Wordperfect version of the entire document but I only have Word so cannot open it fully (the first few pages were OK).
I’ll try and get the whole thing converted and pass on to you.
Regards, Pete R
Abstract:
According to http://en.wikipedia.org/wiki/Climate_sensitivity “Without any feedbacks, a doubling of CO2 (which amounts to a forcing of 3.7 W/m2 ) would result in 1oC global warming, which is easy to calculate and is undisputed. The remaining uncertainty is due entirely to feedbacks in the system, namely, the water vapor feedback, the ice-albedo feedback, the cloud feedback, and the lapse rate feedback.” Here we show that the IPCC estimate of net feedback, namely 2oC (giving a total climate change of 3oC on doubling CO2 from 300 ppm to 600 ppm), is at least a factor of 4 too large when its prediction for climate change when CO2 increases from 300 ppm to 400 ppm is compared with real world temperature increases from 1750 to today. The generally accepted explanation for the greenhouse effect, which involves radiative exchange between CO2 molecules until infrared (IR) radiation can escape from a “220 K black body” layer in the upper troposphere, is seriously flawed. An alternative explanation is proposed for the outgoing IR radiation at the 667 cm-1 CO2 frequency measured by the NIMBUS satellites. It involves absorption by CO2 of incoming solar radiation at 2μ and 1.6μ, which excites molecules to higher vibrational levels of the bond-bending mode, followed by a downward cascade to the ground vibrational state. The most probable quantum jumps involve a change of 1 in the vibrational quantum number, resulting in emission of IR centered around 667 cm-1 and slightly lower frequencies (for v=3 to v=2 and for v=4 to v=3 transitions). In particular, this mechanism can explain the emission measured over Antarctica, which cannot possibly be explained by the standard textbook treatment and its variants. Once this is recognized, it becomes clear that the absorption by CO2 (as measured by the truncated spectrum) is underestimated by about 33%. Therefore the temperature change caused by CO2 alone (without feedbacks) is even higher, reducing the net feedback compatible with the historic record to nearly zero.
Regards, Pete Ridley
Response– Pete, I’m sorry, but there is absolutely no substance to Roger’s work. He simply does not understand the subject at all, that simple.– chris
Re Pete Ridley –
0. Where thermalization of molecular energy is rapid enough compared to photon absorption and emission rates (which is most of the atmosphere’s mass), the different effects of a gas or other agent at different wavelengths can be considered decoupled from each other. In other words, where CO2 molecules are absorbing solar radiation while at the same time absorbing and emitting terrestrial radiation, the effect is practically the same as it would be if there were two different gases, one absorbing solar radiation, and the other interacting with terrestrial radiation. The rapid thermalization means that all the molecules essentially pool their heat capacity into a collective whole (within any given unit volume that is sufficiently small so as to be nearly isothermal while sufficiently large to contain a large enough population of molecules), so that any absorption of radiation heats the whole unit mass within that unit volume and any emission of radiation cools the whole unit mass within that unit volume.
1. The fact that the absorption of solar radiation by CO2 – the SW forcing by CO2 (as opposed the the LW forcing, involving wavelengths longer than about 4 microns) is often not brought up does not mean scientists have forgotten about it. The reason it is often not pointed out is that it is a relatively minor issue compared to the LW forcing of CO2. However, to my knowlegde, I think climate models do include the SW effects of CO2.
Which are a bit complicated, actually. SW absorption by a gas in the stratosphere can actually lead to tropospheric and surface cooling. There are three competing effects – 1. the absorption of SW radiation above the tropopause acts to shade the lower layers, having a cooling effect. 2. The cooling effect is reduced by the resulting reduction in albedo – that is, the cooling is not equal to the increased absorption above (including any increased absorption of SW radiation reflected from below) but only that portion which otherwise would have been absorbed below. 3. the resulting heating of the stratosphere increases LW emission up to space and downward to the troposphere. Thus, after stratospheric equilibration, the cooling effect will be somewhat reduced.
For increased SW heating within the troposphere, the effect on tropopause-level forcing would only be the resulting decrease in upward SW flux due to absorption of SW radiation before or after it is reflected upward, plus some stratospheric LW feedback to that effect (decreased heating from SW radiation from below). Except for that, SW heating within the troposphere that would otherwise have been heating at the surface has no direct effect on tropopause-level radiative fluxes, and thus tends not to force the temperatures of the surface and troposphere one way or the other on average, though it could force a change in convective heat transport.
There are also much larger diurnal cycles in the SW forcing than there are for LW forcing.
The 18 Gt increase in the surface ocean is actually a typo (or ; another part of the website says 118 Gt (1 Gt = 1 trillion kg = 1 Pg).
118/900 = 13.1 %
Chris, your reply to my comment of 17th was, to put it mildly, pathetic. It obviously was too hard for you!
Patrick 027, thanks for that response, which suggests that you know what you are talking about. Who are you and what qualifications/experience do you have? – (name and affiliation will do, then I can check it out myself. I like to know the credentials of the people that I’m talking with). This is way out of my league, so I’ve passed it on to Roger Taguchi and suggested that he joins in here.
Chris will recall award winning science teacher Roger’s involvement in debate several weeks ago on Australian Senator Steve Fielding’s “Climate Change” thread. He has now revised his analysis of the greenhouse effect using a more rigorous approach which confirms his previous conclusions, including that the effect of a doubling of atmospheric CO2 concentration would only result in about 1C temperature increase.
It’s going to be interesting to see if the investigations on both sides of the Atlantic into the “Climategate” scientific scandal (Note 1) is more thorough and open than the “scientific” approach suggested by those leaked UEA CRU files. Relating to this, Roger forwarded a quote from “Some remarks on science, psuedoscience and learning how to not fool yourself” (Note 2). In this address the author was trying to explain the importance of scientific integrity and comparing it with what he calls QUOTE cargo cult science, because they follow all the apparent precepts and forms of scientific investigation, but they’re missing something essential …
there is one feature .. that is generally missing in cargo cult science. .. It’s a kind of scientific integrity, a principle of scientific thought that corresponds to a kind of utter honesty—… .. if you’re doing an experiment, you should report everything that you think might make it invalid—not only what you think is right about it: other causes that could possibly explain your results; and things you thought of that you’ve eliminated by some other experiment, and how they worked—to make sure the other fellow can tell they have been eliminated.
Details that could throw doubt on your interpretation must be given, if you know them. You must do the best you can—if you know anything at all wrong, or possibly wrong—to explain it. If you make a theory, for example, and advertise it, or put it out, then you must also put down all the facts that disagree with it, as well
as those that agree with it. There is also a more subtle problem. When you have put a lot of ideas together to make an elaborate theory, you want to make sure, when explaining what it fits, that those things it fits are not just the things that gave you the idea for the theory; but that the finished theory makes something else come out right, in addition.
In summary, the idea is to try to give all of the information to help others to judge the value of your contribution; not just the information that leads to judgment in one particular direction or another.
UNQUOTE:
This was the California Institute of Technology (CalTech) 1974 address by no less than Richard Phillips Feynman (Note 3), a highly respected American scientist who was awarded the Nobel Prize in Physics in 1965, but is totally relevant today. The full address should be made known to every would-be scientist and instilled into them throughout their training and during their professional development. It would appear that UEA CRU’s Professor Phil Jones; Michael E. Mann, Associate Professor at Pennsylvania State University; Dr. Kevin E. Trenberth, Head of the Climate Analysis Section, National Center for Atmospheric Research; Dr. Gavin A. Schmidt, of the NASA Goddard Institute for Space Studies; etc. have never been made aware of it.
Roger also advises that QUOTE: I mailed hard copies of my Net Feedback manuscript on Mon. Nov. 30 to the Chinese & Indian Ambassadors here in Ottawa, and to the Canadian Prime Minister & the Canadian Minister for the Environment for review and consideration. On Dec. 11, I sent a hard copy to the German Ambassador (Chancellor Angela Merkel has Ph.D. in physics, and a background in quantum chemistry, and may be the only
political leader capable of reading and understanding my document without advisors). ..
Feel free to email my WordPerfect X3 or scanned attachments to anyone concerned (perhaps to the Australian MP’s who stepped down in protest over the carbon tax, to show that they have saved Australia from a wasteful, unnecessary boondoggle). ..
UNQUOTE.
Note the ultimate paragraph – if any of you would like a copy then perhaps Chris can find a way of getting his blog administrator to contact me with your E-mail address so that I can forward it, or you may like to open an E-mail account that can be closed if it starts being spammed.
I hope that Roger is not too busy posting his paper to those heads of state who’ve left Copenhagen in disarray. The UN, all of those heads of state, including our beloved Mr Gordon Brown and your equally loved Barack Obama achieved what? – nothing, despite all of their propaganda leading up to and during COP15. This was such a great success that the UK’s Telegraph today (Note 4) reports QUOTE: Gordon Brown has disclosed that world leaders in Copenhagen are drawing up a “Plan B” for an international agreement on climate change that excludes China. UNQUOTE. What a brilliant political manoeuvre! This will almost guarantee a stop to global climate change – master stroke. Exclude China, the world’s biggest emitter of CO2 which is going to emit more and more as its economy grows to become the biggest in the world within the next few years.
It look’s like it’s going to be another bitterly cold winter this year, even worse than last, which was bad enough. We just had overnight temperatures down to –2C and 8” snow with more to come and that’s just outside of London. It’s now mid-day and its still below freezing, despite the sun blazing away since 9. It’s going to be hell when that predicted mini-ice-age hits around 2020 (Notes 5/6/7/8). We may have reached one of those tipping points that politicians, environmentalists and some scientists keep trying to scare us with.
It’s all so worryng – all of this uncertainty about climate processes and drivers.
NOTES:
1) see http://en.wikipedia.org/wiki/Climatic_Research_Unit_e-mail_hacking_incident#Mann_e-mail_of_11_Mar_2003
2) see http://calteches.library.caltech.edu/51/2/CargoCult.pdf
3) see http://en.wikipedia.org/wiki/Richard_Feynman
4) see http://www.telegraph.co.uk/earth/copenhagen-climate-change-confe/6841260/Copenhagen-climate-summit-Gordon-Brown-has-Plan-B-to-beat-US-and-China-deadlock.html
5) see http://science.nasa.gov/headlines/y2006/10may_longrange.htm
6) see http://epw.senate.gov/public/index.cfm?FuseAction=Minority.Blogs&ContentRecord_id=a17defa8-802a-23ad-4912-8ab7138a7c3f&Issue_id=#update
7) see http://www.monstersandcritics.com/science/nature/news/article_1225169.php/Russian_scientists_predict_new_Ice_Age_in_50_years
8) see http://www.climatescienceinternational.org/index.php?option=com_content&view=article&id=31:vanishing-sunspots-prelude-to-global-cooling&catid=1:latest
Pete Ridley, Human-made global climate change agos(cep)tic
Patrick 027, here’s Roger’s response to your comment QUOTE: Obviously the responses show they misunderstood my argument:
I am not saying that SW absorption/LW emission in the upper troposphere
explains the greenhouse effect, but that it DOES explain the so-called
“220 K black body” radiation observed by the NIMBUS satellites. I guess
they have to read the whole manuscript, not just the abstract, but I
have no faith in their ability any more. UNQUOTE.
How about giving me your E-mail address and I’ll pass on Roger’s paper, but be aware that it is a Wordperfect document.
Regards, Pete Ridley
Response– I can follow along fine, but he’s just plain wrong. The greenhouse effect works by making the planet radiate to space at a temperature colder than the surface, with a difference in emission looking like sigma (T_s**4 – T_eff**4). As Patrick pointed out, the effects of solar absorption are indeed important (especially for ozone in the stratosphere, and even water vapor which has a SW component) but the greenhouse effect is not dependent on this, nor is CO2’s influence in the 667 cm-1 band working without LW absorption and emission. That simple. I’m just pointing out that his argument isn’t worth listening to in any detail, and the types of references and arguments you are choosing to cite in your posts make me think you need to start reading reports from IPCC, NAS, USCCP, etc if you really care about the issues– chris
Pete Ridley –
1. Quote from Feynman sounded familiar – also found here – http://www.realclimate.org/index.php/archives/2009/12/cru-hack-more-context/comment-page-2/#comment-146424
And have you applied that kind of utter honesty in your assessment of what those hacked emails actually show, or in your assessment that various scientists have failed to live up to such ideals?
2.
“The UN, all of those heads of state, including our beloved Mr Gordon Brown and your equally loved Barack Obama achieved what? – nothing, despite all of their propaganda leading up to and during COP15. ”
I suspect some of that is to blamed on a lack of leadership, and some on the failings of human nature, first and foremost, the tendency to take opportunities to screw other people. I wasn’t in the room, haven’t really seen the draft proposals, but the general impression I get is that there is a tendency to pursue patchwork-quilt policies that are not clearly fair or unfair from anyone’s vantage point. It would be better to start with some agreement on a general mathematical formula for allocating responsibilty and compensation, etc, that would be objectively fair assuming the right numbers are plugged into it. We can’t know the right numbers with 100 % accuracy but we know such values do exist and can try to find them or come close. Such an elegant formulation may not be amenable to all the complexities but might perhaps handle a large enough chunk of the issue to make the rest of it a smaller problem.
But one reason in particular that efforts, including the COP15, are falling short, is the partial success of a disinformation campaign waged by fossil-fuel interests and associated parties, which has given power to the such unwise and unhelpful, ignorant, dangerous and demented voices as Sarah Palin, James Inhofe, Rush Limbaugh, Anne Coulter, Sean Hannity, Glen Beck, James Dobson, James D. Kennedy (deceased), and Jon Stossel, to name a few.
3.”perhaps to the Australian MP’s who stepped down in protest over the carbon tax, to show that they have saved Australia from a wasteful, unnecessary boondoggle”
How do you know it would have been wasteful? If climate models are so inept (as is the implication here), why would economic models, which have to account for such an unpredictable, poorly understood, and immensely complex entity as human behavior, do much better? And if we fall back to simple models – ie the rational agent in a market economy with scare resources, etc, an emissions tax looks pretty good to me – internalizing the public cost of an externality would correct the market error, in the sense that externalities lead to an error wherein the market is ‘supposed’ to achieve some optimal performance. (There are ways to deal with international trade – tariffs on subsidies depending on differences in domestic emissions policies among countries. Note that applying the tax to one point on the economic pathways involved, such as, regarding the fossil C emissions (with corrections for those pathways that produce fossil C contained within materials that is not later (depending on how much later, since emissions thousands of years hence distributed over a long time needn’t be of great concern if not large) oxydized to CO2 and released), at the point of extraction of coal, oil, or gas, OR at some other point, such as at power plants and fuel distributors, would tend to have the correct effect, since whoever pays the tax will either raise the price or take a smaller profit, and the higher price will drive demand to more emissions-efficient alternatives, and the smaller profit will drive investment in the same direction, and either by itself will feedback to eventually pull the other with it, with the price signal naturally tending to be redistributed, via market forces, among the benificiaries of emitting activities in a fair manner. Thus the tax can be applied at points where there are large amounts managed by a small number of firms, thus making the enforcement much easier and more efficient than otherwise.) Of course, taking into account other imperfections of a free market, the policy may need to be adjusted, but I think a tax system could still form the core of a very effective and fair policy.
4.”It look’s like it’s going to be another bitterly cold winter this year, ”
So what? Individual climate model runs produce such wobbles about the forced trend – this is expected and seen in nature; it is internal (unforced) variability. Relative to the forced-trend signal, this is noise*, and is mostly averaged out when enough multiple runs are averaged together, leaving behind a smoother projection in response to smoother changes in forcing. This internal variability is an aspect of climate and may take a form that changes as the longer-term average climate changes (*see below), but individual events of such varibility is like ‘weather’, and like day-to-day weather, long-term predictions of specific timings of events are limited by the butterfly effect. However, scientists do study the general texture of such variability and compare observations of reality to model output.
* Noise – except to the extent that there are any changes in the patterns of the variability itself – ie slower or faster wobbles, different spatial-temporal shapes, bifurcations or mergers, or emergences or eliminations of various prominenent modes of such variability (I’m not saying that anthropogenic forcing will produce such a result, but changes in general have that capacity – for example, continental drift could eventually eliminate ENSO by shrinking the Pacific ocean) (a mode of variability is a particular favored pattern in which one or various parts of the system tend to shift in a coordinated manner – such as QBO, MJO, ENSO, NAM (AO) and NAO, SAM (AAO?), PDO, PNA, and AMO – of those, QBO, so far as I know, is the most close-to-periodic, almost like an internal clock; the mechanism which keeps it ‘ticking’ is quite interesting – it is a quasi-periodic downward-propagating reversal of winds in the equatorial stratosphere, which is caused by wind-dependent absorption of momentum transported upward from the troposphere via fluid-mechanical waves, wherein two types in particular (equatorial Rossby-gravity waves, Kelvin waves) transport westerly and easterly momentum, respectively, and are preferentially absorbed under opposite wind conditions. It is a self-organizing phenomenon – it can occur even if the fluid waves that drive it have no such periodicity themselves. On shorter timescales, there are the more familiar examples of cumulus convection and extratropical cyclones, among many others. Of course these are forced, but not in any practically predictable way by factors external to the climate system; however, the climatology or shorter-term tendencies of populations of these phenomena can be understood in part as being due to such forcings – for example, over land, cumulus convection is often more likely in the daytime, when solar heating has a destabilizing effect making such localized vertical convection more likely. But the physics is such that, rather than a horizontally-diffuse vertical overturning that varies smoothly over time according to the radiative forcing and feedbacks, the overturning tends to occur in localized updrafts that vary signicantly over periods of time far shorter than the diurnal heating cycle or, for that matter, larger-scale weather processes such as the development of a synoptic-scale low pressure system or the motion of a cold or warm front. Similarly, extratropical cyclones can develop and grow due to something called baroclinic instability (although latent heating can add fuel to their development, but were latent heating to do it alone, we’d get some other kind of weather, such as localized cumulus convection or a tropical cyclone) (baroclinic instability requires horizontal temperature gradients, or more abstractly, either baroclinic or barotropic instability requires at least one region with a PV gradient of opposite sign to one other region, with spacing and other conditions determining the wavelengths that are unstable), but the presence of baroclinic instability doesn’t directly generate the average weather – it doesn’t work like that; the physics are such that it generates variable weather (individual synoptic-scale low pressure systems with associated fronts, clouds, and precipitation, etc, that form and intensify in prefered areas, move, and decay at some point) that tends to have some average over time, so that forcing shapes these averages in part indirectly via the physics of these phenomena.
And of course, there is also some fluctuation in natural forcings such as the sun (and volcanic eruptions). I would not be surprised at all to find out that a recent reduction in solar brightness has led in part to some relatively cool years – BUT this is relative to other very recent years; the overall upward trend in global average temperature is still quite clear, and the change in solar forcing over the longer-term has not been large enough to explain more than a fraction of the global warming of the last century or two – CO2 forcing change alone is several times larger (the most likely value for change in net anthropogenic radiative forcing in the global average since preindustrial times is almost the same as for CO2 alone, as the larger anthropogenic greenhouse effect is partly cancelled by aerosol cooling, which itself is the net of both cooling and warming effects – though it should be pointed out that aerosol cooling doesn’t just cancel the warming effect of greenhouse gases and leave everything else the same (among perhaps other things, the reduction in solar heating of the surface would, as I understand it, tend to reduce precipitation, more than would a cooling by reducing the greenhouse effect) (one of the contributing reasons why injecting sulphates into the stratosphere might not be such a good idea), but that’s getting beyond what I can give time to right now).
——–
more later…
“Roger’s response to your comment QUOTE: Obviously the responses show they misunderstood my argument:
I am not saying that SW absorption/LW emission in the upper troposphere
explains the greenhouse effect, but that it DOES explain the so-called
“220 K black body” radiation observed by the NIMBUS satellites. I guess
they have to read the whole manuscript, not just the abstract, but I
have no faith in their ability any more. UNQUOTE.”
I don’t know/remember all the details of which satellite looks at what; if the NIMBUS satellite is looking at black body radiation from the Earth/atmosphere, then it is looking at LW (not solar) radiation.
220 K is near a typical tropopause-level temperature, and so at those wavelengths where the CO2 opacity is nearly saturated at the tropopause with respect to radiative forcing (offhand I think this is about 1 micron to either side of the 15 micron (667 cm-1) center of the dominant LW band), we could expect to see a brightness temperature of 220 K as seen from space, except at those narrower portions where the CO2 is so opaque as to concentrate the source region (weighting function) of emission to space into the stratosphere and higher within it, so that the warmer upper stratosphere becomes visible at the expense of reduced visibility of what lies beneath.
In general, increasing opacity of a layer increases it’s ‘visibility’ at the expense of whatever lies behind it. If that layer is colder or warmer than the layer that was behind it, then at least in so far as emission and absorption at local thermodynamic equilibrium are dominating the matter-radiation interaction and what lies behind the layer in question is in total sufficiently opaque (looking down from space, even at locations and wavelengths of relative transparency in the air, there is still the Earth’s land/ocean surface beneath that; however, any degree of transmissivity through the atmosphere above any given level reveals the darkness of space to the layers below), the result is a reduction or increase in the radiant flux coming from that general direction as seen from just in front of the layer in question.
By the way (regarding LW radiation) :
At least for opacity from well-mixed gases, increasing opacity at wavelengths were stratospheric temperature variations lead to increasing emission to space has a cooling effect on the stratopshere but not a cooling effect on the troposphere, because the effect at the tropopause is simply to approach a net LW flux of zero (the upward and downward LW fluxes approach the same value as the opacity becomes such that all that can be ‘seen’ at that level is within a very short distance and thus all at very similar temperatures).
After the center of the CO2 band is saturated for tropopause-level forcing, adding CO2 continues to widen the interval of wavelengths for which a given layer of air exceeds a given level of opacity.
…
And I would be interested in reading the whole manuscript if I suspected I would get something from it worth the time (as it is, I want to spend more time reading such things as:
)
That last bit – I want to spend some time reading this sort of material (I just copied and pasted the titles and authors etc, hence the odd formats and occassional number):
Click to access bengtsson_etal2006.pdf
Storm Tracks and Climate Change
LENNART BENGTSSON, KEVIN I. HODGES, ERICH ROECKNER
Click to access i1520-0442-15-16-2163.pdf
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F1520-0442(2002)015%3C02163:STD%3E2.0.CO%3B2
Storm Track Dynamics
Edmund K. M Chang, Sukyoung Lee, Kyle L Swanson
http://www.pnas.org/content/97/4/1412.abstract
Click to access Hartmann.pdf
Can ozone depletion and global warming interact to produce rapid climate change?
Dennis L. Hartmann, John M. Wallace, Varavut Limpasuvan, David W. J. Thompson, James R. Holton
Two paradigms of baroclinic-wave life-cycle behaviour
C. D. Thorncroft, B. J. Hoskins, M. E. McIntyre
Click to access Thorncroft_1993.pdf
Click to access io0301.pdf
Orlanski, Isidoro, 2003: Bifurcation in eddy life cycles: Implications for storm track variability. Journal of the Atmospheric Sciences, 60(8), 993-1023.
Click to access io0501.pdf
Orlanski, Isidoro, 2005: A new look at the Pacific storm track variability: sensitivity to tropical SST’s and to upstream seeding. Journal of the Atmospheric Sciences, 62(5), 1367-1390.
Click to access i1520-0469-35-3-414.pdf
http://ams.allenpress.com/perlserv/?doi=10.1175%2F1520-0469(1978)035%3C0414%3ATLCOSN%3E2.0.CO%3B2&request=get-abstract
The Life Cycles of Some Nonlinear Baroclinic Waves
Adrian J. Simmons, Brian J. Hoskins
Click to access Methven_2009.pdf
An Interpretation of Baroclinic Initial Value Problems: Results for Simple
Basic States with Nonzero Interior PV Gradients
HYLKE DE VRIES, JOHN METHVEN, AND THOMAS H. A. FRAME
Click to access HHJAS07.pdf
Relating Overreflection and Wave Geometry to the Counterpropagating Rossby Wave
Perspective: Toward a Deeper Mechanistic Understanding of Shear Instability
N. HARNIK AND E. HEIFETZ
Click to access wittman_etal2007_pub.pdf
The Effect of Lower Stratospheric Shear on Baroclinic Instability
MATTHEW A. H. WITTMAN AND ANDREW J. CHARLTON
Click to access Heifetz_et_al_2004_1.pdf
The counter-propagating Rossby-wave perspective on baroclinic instability.
I: Mathematical basis
By E. HEIFETZ1, C. H. BISHOP2, B. J. HOSKINS3 and J. METHVEN3¤
Click to access Heifetz_et_al_2004_2.pdf
The counter-propagating Rossby-wave perspective on baroclinic instability.
II: Application to the Charney model
By E. HEIFETZ1, J. METHVEN2¤, B. J. HOSKINS2 and C. H. BISHOP3
Click to access Methven_et_al_2005_3.pdf
The counter-propagating Rossby-wave perspective on baroclinic instability.
Part III: Primitive-equation disturbances on the sphere
By J. METHVEN1∗, E. HEIFETZ2, B. J. HOSKINS1 and C. H. BISHOP3
Click to access Methven_et_al_2005_4.pdf
The counter-propagating Rossby-wave perspective on baroclinic instability.
Part IV: Nonlinear life cycles
By J. METHVEN1∗, B. J. HOSKINS1, E. HEIFETZ2 and C. H. BISHOP3
Click to access i1520-0469-50-14-2159.pdf
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F1520-0469(1993)050%3C2159%3AMFFSAT%3E2.0.CO%3B2
Momentum Flux, Flow Symmetry, and the Nonlinear Barotropic Governor
Noboru Nakamura
Click to access i1520-0469-49-10-861.pdf
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F1520-0469(1992)049%3C0861%3ANBIOTS%3E2.0.CO%3B2
Nonlinear Baroclinic Instability on the Sphere: Multiple Life Cycles with Surface Drag and Thermal Damping
Jeffrey R. Barnes, Richard E. Young
Patrick 027 (and Chris) Patrick (and Chris), herewith the latest response from Roger Taguchi. QUOTE: Yeah, but the Antarctica emission shows radiation HIGHER than that emitted by the really cold 200 K surface (my main point in the article). Pete, can’t you send him my scanned pdf file? It’s obvious he doesn’t understand my arguments, really. When in real science there is such a clear-cut dispute between two explanations (here, the greenhouse effect), the arguments should be open to discussion by everyone, and not arbitrated by only one side. UNQUOTE.
Why don’t you engage properly with Roger on this by letting me E-mail to you his WordPerfect paper. All that I need is an E-mail address. Meanwhile, I attach to this the Word interpretation of the first three sections of his paper for your consideration as these have not been distorted by Word. When you have responded to those I can send the next 2 sections but there are still several, plus graphs, that Word has not reproduced.
Data
The thermal emission spectra of the Earth as measured by the IRIS Michelson interferometer instrument on the NIMBUS spacecraft of the 1970’s are reproduced at
http://www.ukweatherworld.co.uk/forum/forums/thread-view.asp?tid=16928&start=81
for spectra over (a) the Sahara, (b) the Mediterranean, and (c) the Antarctic. They may also be seen by going to http://climateaudit.org/phpBB3/viewtopic.php?f=4&t=268 and clicking “posted it”. The emission spectrum over Guam is reproduced at http://www.climateaudit.org/?p=2572 .
The general appearance of these spectra is replicated by MODTRAN computer models; for example, one calculated for a surface temperature of 288.2 K (15oC), surface emissivity = 0.98, and outgoing spectral irradiance at 300 ppm CO2 of 260.12 W/m2 is reproduced at
http://en.wikipedia.org/wiki/Radiative_forcing .
Calculation of Temperature Sensitivity (assuming no feedbacks)
For a grey body with emissivity ε and absolute temperature T, the power/m2 emitted is given by the Stefan-Boltzmann Law:
j = εσT4 where σ = 5.67 x 10-8 J.s-1.m-2.K-4 is the Stefan-Boltzmann constant.
Therefore dj/dT = 4εσT3 .
Dividing both sides by j = εσT4 and replacing differentials by differences gives Δj/j = 4ΔT/T,
or ΔT/T = 1/4 Δj/j.
This says that the relative (or %) change in temperature is 1/4 the relative (or %) change in power/m2 emitted. If T = 288.2 K, and j = 260 W/m2, then ΔT = 0.277 Δj. Because T and j are assumed accurate to at least 3 significant digits, we are justified in quoting 3 digits for the proportionality constant obtained from first principles, not an experimental correlation. Equating Δj with ΔF = 3.7 W/m2, the radiative forcing corresponding to a doubling of CO2 from 300 ppm to 600 ppm, the predicted temperature change is 1.02 degrees, assuming no feedbacks. This agrees with the IPCC document which says that 1oC is undisputed.
IPCC Estimate of Net Feedback
Water vapor is responsible for about 70% of all atmospheric absorption of radiation, according to
http://www.lsbu.ac.uk/water/vibrat.html . As global temperatures rise, the saturated vapor pressure of water rises approximately exponentially, as given by the Clausius-Clapeyron Equation:
P = Po .exp(-ΔHvap /RT) where ΔH vap = 40.65 kJ/mol is the latent heat of vaporization,
R= Ideal Gas Constant = 8.315 J/(K.mol),
T = absolute temperature in K,
exp = exponential function, and
Po = a constant
For an increase from 20oC to 22oC, the saturated vapor pressure rises from 17.5 mm Hg to 19.8 mm Hg, an increase of 13% [Handbook of Chemistry and Physics]. Since relative humidity is roughly constant (at around 50%), this means that the concentration of greenhouse water vapor is very sensitive to temperature change, providing a positive feedback mechanism which would amplify the effect of CO2 changes. Against this would be the negative feedback due to possible increased cloud formation which would reflect incoming sunlight before it could be absorbed at the Earth’s surface.
The IPCC estimate of a 3 degree climate change on a doubling of CO2 from 300 ppm to 600 ppm incorporates a guesstimate of 2 degrees net feedback added to the undisputed 1 degree due to CO2 alone. This is reinforced by correlations that purport to show a 3 degree change on doubling CO2 , but correlations are not the same as cause-and-effect.
Regards, Pete Ridley, Human-made global climate change agos(cep)tic
PS: Patrick , I hadn’t read the posts that followed my last one before I posted the latest. There’s a lot to look at but I will simply mention one of your comments relating to those computer (crystal-ball) models. QUOTE: why would economic models, which have to account for such an unpredictable, poorly understood, and immensely complex entity as human behavior, do much better? UNQUOTE. They didn’t do very well with regard to the current economic crisis, did they.
Those global climate models cannot be relied upon until they have been subjected to independent and professional Verification, Validation and Test (VV&T) and been proven to work. This is normal practice in any large commercial organisation before bringing into operation and relying on their computer systems.
I’ll forward to Roger those responses you gave on 19th/20th. Thanks for the effort you are putting in.
Regards, Pete R
0.
“They didn’t do very well with regard to the current economic crisis, did they.”
Well, I think someone actually did predict this – was that just luck though? Haven’t looked further into it.
But in some ways this current crisis may be a bit like the 1998 El Nino. It couldn’t have been predicted ahead of time outside of some time horizon, that a El Nino of that size would occur at that time. But it can be predicted that there will probably continue to be El Ninos of varying intensities.
And anyway, it’s still true that people who have money are generally willing to pay money to buy food.
But my own point was mainly against those who say that we don’t know enough about global warming (or the economic effects of it, for that matter) to justify mitigation policy, but yet are quite confident that those efforts will result in some great harm to the economy or people. Of course, it would be possible to devise a policy that does hurt more than it helps, but it doesn’t follow that all policies would be like that…
1,2
“Those global climate models cannot be relied upon until they have been subjected to independent and professional Verification, Validation and Test (VV&T) and been proven to work. This is normal practice in any large commercial organisation before bringing into operation and relying on their computer systems.”
1.
Well, yes, but we aren’t trying to land on the moon using climate models.
What I mean is that in projecting climate change as a function of human and other effects, just being in the general ballpark of reality provides some valuable information. Of course there is room for improvement and more accurate and precise modelling will help both in better estimating the public costs of emissions and giving better guidance to adaptation measures. But what we have is a lot better than nothing.
(For many purposes, relativistic corrections to Newtonian physics is not necessary; the Earth may be described accurately as being spherical, even though more accurately is is an oblate spheroid, and more accurately still it is…)
2. And climate models are tested. They can’t be tested in the most obvious way before the fact, which is unfortunate because we need to know what happens before it happens regarding any proactive effort to deal with climate change. But:
Climate models can be tested in whole against past climate changes. They can be tested for conditions on other planets.
Climate models can be tested in whole for observations to date. For example, the earliest model(s?) (not computer models, but models in the general sense) from over a hundred years ago predicted sufficient CO2 emission would cause warming. It happened. Modelling from just a couple decades or so ago (James Hansen) projected warming similar to what has happened for a forcing scenario somewhat different than what has happened, but not too wildly different (finding a need to make adjustments to theory or model is not quite the same thing as overturning a theory or showing a model completely fails). Climate models can be tested in how they simulate the effects of a volcanic eruption (against observations around the time of the Pinatubo eruption).
Climate models can be tested in various details – the diurnal cycle, the seasonal cycle, regional variations, modes of internal variability. My impression is that because of all the physical connections, accuracy in these details gives some confidence in simulating other things like global warming. And perfection is not necessary for at least some level of usefulness.
Climate models can be tested for sensitivity to parameterization variations. Some aspects of the system that can’t be explicitly resolved to the grid scale (limited by computing power, generally improving over the years) must be parameterized. These paramerizations are generally based on repeatable observations of small-scale processes themselves, or when they are tuned to produce global conditions better, they are not tuned to reproduce the trend, just the average. Thus they are not tuned to reproduce observed global warming.
See also
http://www.realclimate.org/index.php/archives/2008/11/faq-on-climate-models/
http://www.realclimate.org/index.php/archives/2009/01/faq-on-climate-models-part-ii/
And then there is the question – do we expect results to change much if we make the models ‘this’ much better?
—–
Anyway, from an earlier post by yourself, it appeared that Roger was not arguing that climate sensitivity to an amount of CO2 was lower, but that the CO2 forcing was higher and thus the same response to the same CO2 could occur with less positive feedback – which would make it all the harder to argue that solar forcing has made a sizable difference in the centennial-scale trend.
——
Now I’ll have a look at those graphs…
http://www.ukweatherworld.co.uk/forum/forums/thread-view.asp?tid=16928&start=81
POST”coolhansnl Posted 30/9/2007 16:47 (#253758 – in reply to #248318)”
Spectra looking down from space (NIMBUS) over:
Sahara, Mediterranean, Antarctic
No big surprises there. Where the atmosphere is closer to transparent (between about 8 and 12 microns (roughly ~ 830 giver or take to 1000 , emission seen corresponds more to surface temperature, modulated by surface emissivity (generally 0.9 or higher in LW portion of spectrum).
With the general decrease in temperature with height (below the tropopause), we generally see smaller brightness temperatures where the atmospheric opacity (via absorption/emission) is greater.
(Even though the surface emissivity is less than 1.00, increasing atmospheric opacity even just a little still tends to reduce the brightness temperature seen from space, except wherein emission from within the atmosphere is from a substance concentrated near the surface. For well-mixed optically-relevent agents: for the smallest nonzero opacity, the weighting function of emission to space is concentrated at the surface, with the atmospheric portion being evenly distributed over height (thus including the cold upper troposphere), except for the distortion due to differing line broadenning amounts (for gases) with height, which will skew the weighting function closer to the surface at most wavelengths but will do the opposite near line centers. As opacity increases, more and more of the weigthing function is transferred from the surface to the atmosphere, and more of the atmospheric portion is concentrated towards higher levels, except for the atmospheric portion that is due to reflection from the surface (for the nonzero LW albedo), which is concentrated closer to the surface. This picture remains qualitatively true if the opacity is due to a combination of scattering and emission/absorption, except then a portion of the weighting function goes back into space; if the greenhouse effect is entirely due to scattering, then none of the weighting function is within the atmosphere, and increasing opacity transers more of the weighting function for what is seen from space back into space (and that for what is seen at the surface goes to the surface).)
Hence, the dips in brightness temperature associated with CO2 (from roughly 500 or 550 per cm to roughly 830 per cm), and ozone (near 1000 per cm), and water vapor (wavenumbers above about 1250 per cm or so, and also lower than 500 or 550, and also everywhere else not dominated by another gas, though in varying amounts (not so much between about 830 per cm and 1250 per cm – when humidity is not too high and clouds are absent, this portion of the spectrum is (except for ozone) somewhat transparent, but even at high specific humidity, wherein molecular interactions give rise to additional absorption lines that fill in this ‘atmospheric window’, even when the water vapor concentration is so great as to block nearly all LW radiation from the surface, the concentratio of water vapor near the surface still limits the reduction in brightness temperature as seen from space or from the tropopause level.
But, wherein opacity is high enough for the well mixed CO2, the brightness temperature goes back up a bit because of emission from the stratosphere – as seen in the narrow spike near 667 per cm. The greater concentration of ozone in the stratosphere relative to the troposphere also raises the brightness temperature over it’s absorption band relative to where it would be for a well-mixed gas (even on the wings of the band).
With that in mind, you might guess what’s going on in the Antarctic case. Under various conditions – at night over land surfaces (espcecially with clear skies, low humidity, and high elevation), and in the polar regions (especially in winter), the surface temperature can be/is lower than the atmosphere at some level in the troposphere. This is an inversion. Inversions can occur in some other conditions, such as with fronts or with subsidence above the boundary layer (in those cases, the increase in temperature with height might not actually reach the surface, but the inversion might be strong enough so that at the top of the inversion, the temperature is still higher than at the surface).
The increase in brightness temperature associated with the CO2 band, and the O3 band and presumably the water vapor bands or parts thereof (depending on how water vapor is distributed relative to the inversion) is readily explained by the presence of such an inversion.
An inversion near the surface is readily seen in the vertical soundings from the Arctic region also posted in that comment.
The Following comment (“DeWitt Posted 30/9/2007 16:52 (#253760 – in reply to #253576)” also has some interesting graphs. Note the brightness temperatures seen from the surface looking up (which will be higher when opacity is greater and temperature decreases with height). The spectrum from Barrow Alaska shows evidence of an inversion within the troposphere – there is a general increase in brightness temperature going into the CO2 band from either side, as the darkness of space is replaced by emission from the atmosphere, but then near the center of the band, the tendency reverses, presumably because the weighting function is then being compressed into the inversion so that further opacity increases blocks more of the radiation from the warmer air near the top of the inversion.
______
Note that these inversions don’t invalidate the concept of surface and lower atmospheric warmth via a greenhouse effect, because a decrease of temperature with increasing height is still the overall tendency of the atmosphere.
The simplest radiative-convective model would be a single column of atmosphere wherein convective fluxes are adjusted to maintain a convective (adiabatic, or moist adiabatic in those layers with cloud) lapse rate whereever radiative fluxes alone would create a lapse rate higher than that. This is a good first approximation of reality.
Over the whole globe, there are parts of the troposphere that are not being convectively mixed locally, which can be because the temperature profile is stable to convection (although the role of water vapor in changing the convective lapse rate allows convection to not occur even when it could; so long as the lapse rate is stable to dry convection, moist convection must be initiated first before it can sustain itself).
But the whole troposphere is still convectively linked; in areas that are convectively stable, generally warmth found aloft is transported horizontally from areas where there is convective transport of heat from the surface. And some convection takes place as large-scale overturning.
“The greater concentration of ozone in the stratosphere relative to the troposphere also raises the brightness temperature over it’s absorption band relative to where it would be for a well-mixed gas (even on the wings of the band).”
No, wait, that wasn’t quite right. Depending on latitude and season, a significant thickness of the lower stratosphere can be about as cold as the tropopause, and … well, it depends on just how much ozone there is and where it is within either layer; it’s possible that in at least portions of the band, the brightness temperature is reduced more than it would be if it were well mixed; I don’t know enough of the specifics offhand to say which it is and when and where.
Patrick 027, I have no argument against much of what you say but I think that either you merely overlooked some important little words of mine or you deliberately ignore them.
QUOTE: But my own point was mainly against those who say that we don’t know enough about global warming UNQUOTE.
My position is that we do not know enough about the causes of any global temperature changes that may be taking place to justify a global taxation system based upon one improbable cause. The politicians (and environmentalists) are proposing to impose a tax on our use of the cheapest form of energy that is available to the majority, in particular to those who can hardly survive, never mind enjoy the privileges that you and I enjoy. In the process they are creating an artificial financial market that contributes nothing worthwhile to global economies but could make the privileged few – e.g. Al Gore – very very rich indeed (and at who’s expense? – yours and mine – no thanks).
Response– Nonsense. The predictive and explanatory power of CO2’s influence on climate change is overwhelming. See Richard Alley’s latest AGU talk for a geologic perspective. Read the extensive literature as summarized by the AR4, National Academies, USCCP, Copenhagen report, and thousands of documents over the decades in the refereed literature which demonstrate with very very high confidence a dominant anthropogenic signal in the climate system. Not only does this paradigm make specific predictions which have been borne out, but no other competing hypothesis is remotely as powerful.– chris
QUOTE: .. climate models. .. what we have is a lot better than nothing. UNQUOTE. This is only opinion. To many of us they are little better than crystal ball gazing due to the enormous uncertainties surrounding climate processes and drivers.
Response– It isn’t opinion. Climate models now do a terrific job of simulating the key features of climate change on Earth, and the important aspects of CO2’s influence on climate will not be undermined by the things we don’t know. It’s physics, pure and simple. This is what we do in science…you have a specific hypothesis which has a theoretical ground, you test it with observations, you feed numerical models, etc and the best answer is that the current science is not significantly off the mark. The blogosphere or Roger’s astrology science are not going to change this. If you pick out a specific model from a specifc group who are interested in a specific variable, I guarantee that if you can actually try, you’ll find something in the literature which examines it–assesses the models usefulness and weaknesses– etc. USCCP has a report on Strengths and Limitations of Climate models, AR4 has a whole chapter on model evaluation. Let’s do some research before we express our “opinions” about crystal balls.– chris
QUOTE: And climate models are tested. UNQUOTE. Yes they are, but by whom? You seem to have missed the words “independent”, “professional”, “verification” and “validation”. The importance of those words is underscored by the “Climategate” scandal.
Response– No it isn’t. ClimateGate only succeeded at making the angry people angrier and the conspiracy nuts nuttier. Because of the mass attention, it has also served as a distraction to people who have better things to do, but nothing in the e-mails points to any conspiracy or any fundamental flaw in the data used to assess global temperature anomaly or anthropogenic attribution. It’s just served as another chance for skeptics to mislead, distort, and attack. As for models, well, depending on what you’re looking at, everyone (the sea ice people, the radiation people, the carbon cycle people, the water vapor people etc) are trying the best they can to get things right and get observations and models as close to reality as possible. No one has anything to gain by artificially creating some pre-conceived answer. This does nothing for science, and it’s impossible that such a widespread “scam” would survive the self-correcting nature of science and people looking hard at the data and models– chris
You provide links to RealClimate, but those “Climategate” E-mails indicate that Gavin and his associates may be less than open-minded and fair in their approach to debate on climate science. The investigations being undertaken on both sides of the Atlantic, if independent of political influence, should expose the truth about what was being done in the name of science.
Response– Yea, ok– chris
QUOTE: Roger was not arguing that climate sensitivity to an amount of CO2 was lower, .. positive feedback.. … UNQUOTE. As I understand it, Roger argues that empirical evidence shows that the positive feedbacks clamed by the IPCC are seriously exagerated.
Response– Roger is currently taking issue with fundamental physics of how the greenhouse effect operates, but on another note, no empirical evidence supports this notion about sensitivity. In fact, the past climate record is the cornerstone upon which the IPCC sensitivity estimates are based on– chris
You seem not to have noticed my repeated use of the word “significant” with respect to the impact of our emissions of greenhouse gases.
Thanks for the link to http://www.ukweatherworld.co.uk/forum/forums/thread-view.asp?tid=16928&start=81 which I’ll have a look at and pass on to Roger along with your comments.
Regards, Pete Ridley, Human-made global climate change agos(cep)tic
Chris, your comments are more akin to dogma than science.
“Thanks for the link to http://www.ukweatherworld.co.uk/forum/forums/thread-view.asp?tid=16928&start=81 which I’ll have a look at and pass on to Roger along with your comments.”
You provided me with that link. Thank YOU. 🙂
—–
My position – see Chris Colose’s in line comments.
But I’ll just add/emphasize:
It’s extremely reasonable to expect that adding x CO2 will cause y +/- z degrees warming and various attending diurnal, latitudinal, seasonal, regional, interannual, etc, shifts in weather pattern tendencies, circulation and rainfall and temperature variations, etc.
Is there uncertainty? Of course (especially in some regional effects – which is not really all that comforting – it makes proactive adaptation harder, and tilts the balance towards mitigation being better* ). But there is a big difference between admitting some nonzero possibility that the response to a doubling of CO2 could be less than 2 deg C or more than 4 or 4.5 deg C (before large ice sheet feedbacks and biogeochemical feedbacks), and insisting that either is likely, or especially one of those is very likely and not the other. Some contrarians tend to emphasize that sensitivity is likely closer to 1 deg C – could it happen – I suppose it could (maybe the present day arrangment of continents and extant species etc. creates by some unlikely luck an anomalously low climate senstivity within some range of temperatures warmer than recent interglacials (the glacial-interglacial variation corroborates model results for climate sensitivity), via mechanisms as of yet unidentified or unquantified – but how likely is that, really?), but they have no good basis to *expect* that.
And if we prepare for that small possibility, should we not also prepare for the small possibility of something considerably more catastrophic than is generally produced by models (huge CH4 positive feedbacks (with catastrophic methane hydrate/clathrate releases triggering tsunamis), CO2 feedbacks that amplify the anthropogenic additions, massive sea level rise by 2100 (more than the 1 or perhaps 2 m generally expected, which is still plenty to be concerned with, and note that sea level rise is not expected to stop at 2100 – it’s a question of how fast will sea level respond, perhaps at least as much as where it ultimately goes), reduced oxygen in the oceans…?).
Patrick 027, of course, anyone can dream up any scary scenario that they choose, but there iss no justification for over-reacting to it, which is what the politicians who support the UN would have us do. Why do they want this? The UN’s COP15 fiasco is nothing to do with controlling global climates but everything to do with:
– enhancing the status, power and finances of the privileged few,
– establishing a framework for global government,
– redistributing wealth from the taxpayers in developed economies to the privileged few in underdeveloped economies.
If you are interested in talkiinmg about the politics of climate change then join us on Senator Steve Fielding’s “Climate Change” thread at http://www.stevefielding.com.au/forums/viewthread/125/P5865/
* – what could tilt the balance back in favor of adaptation is the potential for significant unforced variability, or naturally forced variations that are sufficiently large. For the later, orbital forcing is too slow to worry about in the same way, and volcanic and solar forcings don’t tend to be so big. My understanding is that internal variability can cause significant regional variations without much of a global average temperature change. Except for sea level variation and … well, not all, but a significant portion of the concern of climate change involves regional effects.
But shorter term variability doesn’t produce the same kinds of concerns as longer term variability (river flows and lake levels, especially downstream in large basins, should tend to reflect average conditions over longer time periods and over distances) (as with climatic states, a mature climax community ecosystem can be defined to include some continual small-scale disruption – a downed tree here and there, etc. – it is different when there is large-scale deforestation or tree-death, etc.)
As for longer term variability … well how much is there?
If the natural variability caused meanderings of storm tracks and associated precipitation belts large enough to shift such features completely into and out of a region, then one could say that the variability is saturated in at least one respect, and global warming wouldn’t make it ‘worse’ per se.
But where are any cases of such saturation (on the relevant timescales)? I don’t know of any offhand. But I still haven’t read through most of Ch 6 of IPCC AR4 WGI (this discusses past climate changes).
And, even with some such saturation, other things can still change – the variation between precipitation – evaporation between the center of high precipitation belts and the centers of dry zones can change, and also, with global warming in general, even though temperature doesn’t necessarily increase much everywhere at all times, some regions and seasons will likely emerge with temperatures higher than any previously existing, and the fraction of days exceeding any high temperature threshold can increase, while the coldest environments and periods will tend to dissappear.
Also, I’d suggest that the naturally-supplied uncertainty in the future doesn’t saturate the potential for uncertainty. And note that uncertainty makes proactive adaptation more difficult. What if we forecast that some region will get wetter and some region will get dryer, and taking into account soils, etc, we invest in some aquaducts, reservoirs, and desalination plants, etc, and then find out that we were wrong and now we’ve wasted money and effort and, if other changes occured, still have a problem to solve – yet, if our best estimate is a particular set of changes, it makes little sense to do nothing to prepare.
And why is change necessarily bad?
Well, it isn’t entirely and generally.
But adaptation tends to be more costly when it must be done rapidly. This goes for ecological succession and biological evolution. Rapid change that is large and, I’d think, reaches into relatively unfamiliar territory (as in hasn’t occured for x thousands or x millions of years, etc.) is more likely to cause ecological stresses and extinctions.
… and there’s more but I have to take a break. Could be awhile…
“Patrick 027, of course, anyone can dream up any scary scenario that they choose, but there iss no justification for over-reacting to it”
And what’s your justification for under-reacting?
—-
By the way – besides biased distorted emphasis on uncertainties, the contrarian/denialist/’skeptic’ arguments generally rely on one or more of:
1. illogical argumentation
2. wrong facts or very poor understanding of the physics (or chemistry, etc.)
3. To the extent that they get the facts and logical reasoning correct, they can only get to the conclusions they reach by ignoring some other facts. In other words, everything that the contrarian community knows that is actually correct is also known by the mainstream community of climate scientists, but in addtion to that, the mainstream community knows more – often much more.
Contrarians are the people who find an elephant’s trunk and continue to insist that it is a hose even when they are shown the tusks and legs, and fecal material. They find a corner of the Mona Lisa which contains none of the face and show it as evidence that the painting is not the Mona Lisa.
Patrick 027, herewith Roger Taguchi’s response to your comments of 21st at 12.46 & 12.54 a.m.
QUOTE:
“Explaining” the spectrum over Antarctica as due to a “temperature inversion” explains nothing: it just means that the inversion is noted, without explaining why or how. By contrast, the temperature inversion in the stratosphere is well-understood as due to absorption of incoming Solar ultraviolet (and visible) light by ozone which by collisional transfer and by recombination of O atoms with O2 molecules heats up the air at that altitude. What is desperately missing is a similar understanding of molecular processes involved in the greenhouse effect in the lower troposphere. Just because this is not yet in the textbooks does not make it wrong.
The ukweatherworld discussion continues to repeat the “measurement” of temperature by the height of the peak of absorption, which .. is garbage. This non-understanding of “black body” temperature is behind the mistake attributing the truncation of the CO2 667 wavenumber absorption as a measurement of “220 K black body” radiation, when in truth almost complete absorption by CO2 is masked by upper-atmosphere emission by CO2 molecules (which, unlike near the Earth’s surface, don’t undergo enough molecular collisions to be quenched, and so lose energy by emission). These upper-atmosphere CO2 molecules are excited not from the Earth’s surface, but by incoming Solar radiation at higher frequencies (lower wavelengths).
I’m afraid continuing to “dialogue” with these people is like discussing Darwinian evolution with a creationist. UNQUOTE.
Ref. your comment on 21st at 02.06 p.m. I submitted too quickly and unfortunately Chris’s thread, unlike Senator Fielding’s, does not allow editing. As for those un-quantified changes QUOTE: .. y +/- z degrees warming and various attending diurnal, latitudinal, seasonal, regional, interannual, etc, shifts in weather pattern tendencies, circulation and rainfall and temperature variations, etc. UNQUOTE, the point is what is their significance in relation to natural changes? Although QUOTE: It’s extremely reasonable to expect that adding x CO2 will cause .. UNQUOTE will have some impact, how significant is that 4% of CO2 added by humans significant when compared with the 96% increase due to natural sources? As the article “Water Vapor Rules the Greenhouse System” (Note 1) says QUOTE: Just how much of the “Greenhouse Effect” is caused by human activity? It is about 0.28%, if water vapor is taken into account– about 5.53%, if not. UNQUOTE – trivial really.
Note 1) see http://www.geocraft.com/WVFossils/greenhouse_data.html
Regards, Pete Ridley, Human-made global climate change agos(cep)tic
PS: If I don’t get back before the 25th, have a great Xmas and all the best for 2010.
Roger Taguchi misunderstood the point …
Patrick 027, perhaps if you find tme yu can explain what point Roger misunderstood.
I’ll get back to Roger Taguchi’s stuff later; for nw:
http://www.geocraft.com/WVFossils/greenhouse_data.html
– this website is complete Bull S–t!
“Water vapor constitutes Earth’s most significant greenhouse gas, accounting for about 95% of Earth’s greenhouse effect (4). Interestingly, many “facts and figures’ regarding global warming completely ignore the powerful effects of water vapor in the greenhouse system, carelessly (perhaps, deliberately) overstating human impacts as much as 20-fold.”
W R O N G.
Water vapor is the dominant gas, but it is NOT 95 % of the greenhouse effect. Furthermore, if all the CO2 were removed, the water vapor feedback would involve a large reduction in the water vapor greenhouse effect. WATER VAPOR IS NOT IGNORED BY THE IPCC OR ANY SERIOUS SCIENTIST.
See http://www.realclimate.org/index.php/archives/2008/08/are-geologists-different/comment-page-5/#comment-97023
and
http://www.realclimate.org/index.php/archives/2005/04/water-vapour-feedback-or-forcing/
and/or
http://www.skepticalscience.com/Evaporating-the-water-vapor-argument.html
and
http://www.scholarsandrogues.com/2007/07/23/anti-global-heating-claims-a-reasonably-thorough-debunking/
and/or
http://scienceblogs.com/illconsidered/2006/01/water-vapor-is-almost-all-of.php
AND PLEASE SEE
(Note the graph of anthropogenic radiative forcings. These things are computable!).
and
AND
Click to access RadiationBudget.pdf
(NOTE TABLE 3) – BUT ALSO NOTE that the Kiel and Trenberth radiation budgets don’t state what the tropopause-level forcing is, and are based on some approximation (the surface is not actually a perfect blackbody in the LW spectrum), but nonetheless a good place to start (and I don’t think the approximations wouldn’t amplify the importance of one gas over another all that much).
(links to those four can be found here:)
http://www.realclimate.org/wiki/index.php?title=Water_vapor_accounts_for_almost_all_of_the_greenhouse_effect
(note that there is overlap among greenhouse agents. Removing all CO2 from an atmosphere with clouds and water vapor will cause less radiative forcing than removing that same amount of CO2 if the clouds and water vapor were not present but keeping temperatures the same**. Similarly, after some initial amount of CO2, due to what you could call additional amounts result in progressively less radiative forcing per unit amount (but approximately the same per doubling, at least within some range) – at least if the tropospheric and surface temperatures are kept the same, but allowing stratospheric equilibration.** (** large changes in radiative forcing can be different between forward and reverse changes because radiative forcing depends on the current state of the climate system, including overlapping agents, etc, and, for LW forcing, a direct dependence on the temperature distribution. However, the feedbacks are also different, and if and when there is no hysteresis in the system, allowing climatic equilibrium to be reached before and then after the change, the forward and reverse change will take the system back to where it started. As an example of this, considere the effect of tropopause height. There might be some difference due to spatial-temporal variations, but for the 1-dimensional model averaged over latitude, the day and the year, etc, if there is no greenhouse effect, than all LW cooling must occur at the surface, which means the atmosphere will tend to be isothermal with the surface or, if there is some direct solar heating of the atmosphere, temperature will increase in height from the surface. Adding CO2 or another greenhouse agent to such a situation will actually result in either a zero radiative forcing at the top of the atmopshere, or a negative forcing if the atmosphere is heated directly by the sun. But there is no troposphere in this situation – until there is a troposphere, we can consider tropopause-level to be at the surface, and note that the radiative forcing there, even after ‘stratospheric equilibration (in which the atmopshere above the tropopause – in this case, the surface – has a temperature reduction), is positive at the tropopause level – in this case the surface. The tropopause level eventually lifts off the ground and rises with height as the the greenhouse effect is increased (I’m not trying to suggest that the tropopause height is only affected by the greenhouse effect – I think greater solar heating of the troposphere and surface will also tend to raise the tropopause level). Also and perhaps more obviously, the relative lack of water vapor at cold temperatures will increase the radiative forcing of additional CO2 relative to what it would otherwise be – but then, the water vapor feedback due to the same amount of water vapor addition will be smaller by the same amount. And so on. Note that the entirety of the greenhouse effect (including clouds) keeps the surface about **33 K warmer than it otherwise would be, but this doesn’t include albedo feedbacks (including clouds); if all the greenhouse effect were removed, the Earth would freeze over, and at some point, the climate sensitivity actually goes through infinity and becomes negative (indicating an unstable equilibrium – in this case, between two other stable equilibria) as the edge of the sea ice/snow/etc reaches sufficiently low latitudes (depending on meridional heat transports); once frozen over, a thaw requires greater forcing (solar or greenhouse) than would have prevented the freeze-over; hence there is hystereris in this case (‘Snowball Earth’). There is some hysteresis involved in glacial-interglacial transitions; vegetation feedbacks (ecological succession) might also provide a hysteresis mechanism regarding regional precipitation changes. A more subtle form of hysteresis would be if after each freeze-thaw cycle (not going into Snowball territory), the meltwater altered oceanic circulation in such a way as to cause the next ice sheet to form in a different location – this could result in a periodic attractor or a strange attractor – but that’s hypothetical, I know not of such a condition. However, biological evolution provides a sort of generic hysteresis to the whole thing.)
(absent historesis, one can define a single unique climate sensitivity (as a function of climatic state or of total forcing) by considering climate response to gradual forcing changes such that the climate remains near equilibrium, or alternatively by following a series of small forcing changes, allowing equilibrium to be reached after each step.)
** 33 K is calculated based on zero horizontal or temporal (diurnal, seasonal, interannual and intraseasonal and synoptic-scale, mesoscale variations, etc.) temperature variation. Such temperature variation generally allows a colder equilibrium global average temperature because of the nonlinear relationship between blackbody radiation and temperature. However, I estimated that for the Earth’s surface, realistic temperature variation only makes a difference on the order of 1 K, and note that in much of the atmopshere, horizontal and seasonal and especially diurnal temperature variations (over land – could be the opposite over water, but that’s perhaps a small variation in the air over no variation at the ocean surface) are smaller than at the surface.
“Human activites contribute slightly to greenhouse gas concentrations through farming, manufacturing, power generation, and transportation. However, these emissions are so dwarfed in comparison to emissions from natural sources we can do nothing about, that even the most costly efforts to limit human emissions would have a very small– perhaps undetectable– effect on global climate.”
W R O N G.
Human activity is the cause of approximately all the 100 ppm CO2 increase in the atmosphere since preindustrial times. This has a calculable radiative forcing. …
THIS WILL HAVE TO BE CONTINUED LATER, in the meantime:
see also:
http://scienceblogs.com/illconsidered/2008/07/how_to_talk_to_a_sceptic.php
An optimal climate?
http://www.realclimate.org/index.php/archives/2008/08/are-geologists-different/comment-page-6/#comment-97423
http://www.realclimate.org/index.php/archives/2008/08/are-geologists-different/comment-page-6/#comment-97535
Patrick 027, so, in your humble opinion http://www.geocraft.com/WVFossils/greenhouse_data.html QUOTE: .. is complete Bull S–t! UNQUOTE. Your modesty is no doubt only surpassed by your beauty.
“Water vapor constitutes Earth’s most significant greenhouse gas,” – this would seem to be CORRECT if we can believe what Gavin Schmidt’s comment (Note 1) that QUOTE: Making some allowance (+/-5%) for the crudeness of my calculation, the maximum supportable number for the importance of water vapour alone is about 60-70% UNQUOTE.
“accounting for about 95% of Earth’s greenhouse effect” – more CORRECT then WRONG if we can believe the comment by Robert H. Essenhigh, Professor of Energy Conversion in the Department of Mechanical Engineering, Ohio State University in the American Chemical Society “Viewpoint” QUOTE: water accounts, on average, for >95% of the radiative absorption UNQUOTE.
“many “facts and figures’ regarding global warming completely ignore the powerful effects of water vapor in the greenhouse system” – CORRECT and verifiable by doing a Google of “global warming” (but ignoring the Wikipedia entry, since “Climategate” has cast doubt upon anything on that site relating to climate change (Note 2) QUOTE: Connolley, one man in the nine-member team who is a U.K. scientist, a software engineer and Green Party activist, took control of Wikipedia’s entries to see that any trace of the true climate history would be erased. UNQUOTE (I see that your Realclimate hero Gavin Schmidt is also given a mention). One of those articles “World View of Global Warming” (Note 4) mentions CO2 8 times but water vapour not once.
While following up on this part I came across an interesting item on recent satellite measurements (Note 3) which included a link to an article “Is “several degrees” of warming “virtually certain,” as NASA claims?” which questions the validity of the claim that CO2 is a well-mixed gas. In that article is a link to a paper “Climate Change: Driven by the Ocean not Human Activity” (Note 5) by William M. Gray, Professor Emeritus, Dept of Atmospheric Science, Colorado State University.
You chose to ignore my earlier request for you to let me know what your science credentials are so I have to assume that they are not very significant as far as climate processes and drivers are concerned. On the other hand, Professor Essenhigh and Professor Gray have achieved reasonable academic levels. Who would you take notice of if you were in my shoes, Patrick07 or Professors Essenhigh and Gray?
Muist go – the boss is callng for assistance with the Xmas preparations.
NOTES:
1) see http://www.realclimate.org/index.php/archives/2005/04/water-vapour-feedback-or-forcing/
2) see http://www.wnd.com/index.php?fa=PAGE.view&pageId=119745
3) see http://www.globalwarming.org/2009/12/17/is-%E2%80%9Cseveral-degrees%E2%80%9D-of-warming-%E2%80%9Cvirtually-certain%E2%80%9D-as-nasa-claims/
4) see http://www.worldviewofglobalwarming.org/
5) see http://typhoon.atmos.colostate.edu/Includes/Documents/Publications/gray2009.pdf
Regards, Pete Ridley, Human-made global climate change agos(cep)tic
MERRY XMAS TO ALL
Response– Actually Patrick is correct, and there’s no need to believe anyone’s word (but if I had to pick, I’d take Patrick’s word over Essenhigh’s or Grays). Of the greenhouse effect, roughly 50% of the infrared opacity is due to water vapor, 25% to clouds, 20% to CO2, and about 5% to the other trace gases (ozone, methane, etc). The “95% fact” is just a made-up figure that cannot be verified by any radiative transfer calculation. Still further, these simple numbers don’t really do full justice to the relative importance of various gases, since the non-condensable GHG’s provide the skeleton by which water has most of its effect. If you were to remove all the CO2, O3, methane, etc from atmosphere then you’d also lose much of the water vapor effect and result in a collapse of the terrestrial greenhouse effect.– chris
Yes, what Chris said.
1.
And- “so, in your humble opinion ” – an opinion shared by anyone who knows about this stuff, though often expressed with different verbage.
“You chose to ignore my earlier request for you to let me know what your science credentials are so I have to assume that they are not very significant as far as climate processes and drivers are concerned. ”
I didn’t ignore but chose to go to other issues first. Anyway, I don’t have an advanced degree, but I do have a degree in the subject (atmospheric/oceanic science). But I am standing on the shoulders of giants – which is not to say that I am taking their word for it; I seek to understand, not just to memorize.
You don’t have to take my word – look it up in textbooks, etc. (and think, does this make sense?), read through the Kiehl and Trenberth study and judge for yourself whether it’s way off or approximately correct.
I suspect I know considerably more than Singer or Essenhigh regarding radiative forcing of climate. It’s not that hard, really. Have either of them even had any formal training on atmospheric radiation? If they have, it doesn’t show. And note that a few of Singer’s own references blatantly contradict him ( See again http://www.realclimate.org/index.php/archives/2008/08/are-geologists-different/comment-page-5/#comment-97023 )
(Atmospheric radiation – for me anyway – is qualitatively one of the easiest things to wrap my mind around; I find it very intuitive. For me, the fluid mechanics aspect of the climate system has been and still is much more diffilcult to understand – but it is very interesting.)
As for Gray, well, he was important in his field so far as I know, but he’s lately been cutting his own reputation apart for being, let’s say, a bit off the mark.
And what are your qualifications, again? (feel free to take that as rhetorical).
___
2. back to Singer’s errors, where I left off:
A.
Data on C isotope distributions and CO2 fluxes help illuminate how C cycles through the system. There are things that we (not me personally, per se) actually know about where C is coming from and where it is going and why, including oceanic chemistry (CO2, H2CO3, HCO3-, CO3- -; PS a point of confusion for myself – can CO2 exist in water as CO2 – in other words, when dissolving CO2 in water, are the going into solution and formation of H2CO3 two seperate steps or the same step? Anyway, there are chemical equilibria between H2CO3 and HCO3-, and between HCO3- and CO3- -, … bunch of interesting stuff there, maybe check out links from this website we’re on?)
We know human activity has removed C from land vegetation (deforestation) and from fossil fuels, and addeed that C to the air (mainly as CO2).
We know there has also been some subsequent reforestation and also some fiddling with the N cycle, etc, that has reduced the net anthropogenic emission of CO2.
We know that there is a CO2 fertilization effect, and that plus some (but not all) changes in climate could cause an increase in organic C stored on land. However, it is not the case that surface organic C changes in proportion to atmospheric CO2; an increase in photosynthesis can lead to an increase in subsequent respiration/oxydation, … and other climate changes can cause C losses from vegetation and soil.
We know that adding more CO2 to the air increases the partial pressure and thus increases the equilibrium concentration of CO2 in the water. However, CO2 doesn’t exist in water solely as a dissolved gas. There is a time-dependent limit to how much how fast the upper ocean can take up from the atmosphere and exchanges with the deep ocean are slow.
Different reservoirs of C have different isotopic ratios (C-14 decays according to time spent outside the atmosphere; C-14 is produced in the atmosphere by cosmic rays; the production has some variability but C-14 ages can be callibrated to calendar years by C-14 dating of tree rings, etc.), and some processes involved in transfering C from one reservoir to another exhibit isotopic fractionation (photosynthesis produces organic C depleted in C-13 relative to the source CO2, with some variation between C-3 and C-4 photosynthesis). The effects of anthropogenic emissions include C isotope ratio changes among the reservoirs that depend on how the C cycle works, and C isotope measurements can be used to clarify the picture.
C has accumulated in the atmosphere and in the ocean; there is no significant non-anthropogenic decling in C anywhere that would be alternative candidate for the source of the additional CO2.
Of course, it could be argued, in the absence of knowledge to the contrary, that were it not for some warming, perhaps natural warming, or some other natural change, or something else, then perhaps much more of the additional CO2 would have gone into the oceans or otherwise elsewhere besides the atmosphere, and that it is this other change which is truly responsible for the increase in atmospheric CO2. However:
a. since the last ice age, for several thousand years, CO2 has remained relatively constant, only to shoot up ~ 100 ppm (AND COUNTING) just as anthropogenic emissions exploded. (By the way, this increase has been much faster than what occured as feedback during the last deglaciation.)
b. The simple temperature feedback wherein colder water can dissolve more CO2 is actually relatively weak and could not account for the recent change; it also cannot by itself account for most of the glacial-interglacial CO2 feedback – even with the temperature change solubility feedback (which is partly counteracted by a salinity-solubility feedback (increasing masses of fresh water, such as in ice sheets, would have left behind somewhat saltier oceans)), the upper ocean’s CO2 (in all forms) would have decreased going from interglacial to glacial conditions in order to be in equilibrium with the lower atmospheric CO2; the actual gain of C occurs in the deep ocean. It takes time for C to accumulate in the deep ocean.
c. We (not me personally per se) know some things about the physics and chemistry and biology and can have reasonable expectations for how the C cycle works based on that, and see again above points about measurements of C isotope ratios, etc.
B.
What Singer might be thinking overwhelms the anthropogenic emissions are the natural fluxes between the atmosphere and ocean and between the atmosphere and land vegetation and soil. True, these fluxes together in either direction (to or from the atmosphere) are roughly 20 times the anthropogenic emissions. However, they are balanced, or tend to be over time – except for imbalances that redistribute the CO2 accumulation from the atmosphere to the ocean and vegetation+soil.
Also, so you know, anthropogenic emissions are many times larger than geological emissions. Over time, geological emissions tend to be balanced by geological sequestration, which is typically dominated by chemical weathering + carbonate mineral formation with about 20 % of geologic sequestration being organic C burial, but that ratio can fluctuate a bit over geologic time. There is a generally** negative feedback to climate change via chemical weathering rate changes, due to warmer conditions with greater precipitation (global average), but this is typically*** a slow acting feedback (evidently unable to prevent glacial-interglacial fluctuations).
** – it also depends on the aligment of regional climate conditions with landscapes. Greater land area (note, this tends to occur during glaciations – however, this may be accompanied by an increase in geologic emissions from oxydation of exposed continental shelf organic C) and more mountainous terrain (Himalayas now, Appalachians during cold part of Ordivician) can lead to increased weathering unless they are in dry or cold places. Note that erosion by glaciers can enhance chemical weathering rates downstream if it is warmer there and still wet (also a potential long-term positive feedback to ice ages?, or is it important for there to be glacial-interglacial fluctuations in order for this to work from continental ice sheet erosion?). Chemical weathering and organic C burial are also affected by biological evolution. And organic C burial is affected by climate and geography. Continental drift and plate tectonics, and biological evolution, can force changes in climate in part via changes in chemical weathering and organic C burial. A change in geological emissions tends to change climate with the general tendency to change chemical weathering; the new climate equilibrium is reached when atmospheric CO2 levels stabilize at a new value.
*** – the proposed aftermath of a Snowbal Earth episode could be described as a hot carbonic-acid sauna; given the extreme heat and the abundance of left-over glacial debris (high surface area), chemical weathering could occur rather fast in such cases.
(However, if it gets two hot, the thermodynamic stability of various carbonate minerals decreases, inhibiting the geological sequestration of CO2. How hot? It depends on the minerals – See
“Initiation of clement surface conditions on the earliest Earth”
http://www.pnas.org/content/98/7/3666.full )
—
Please note that, where I have been talking of anthropogenic CO2 accumulation in the atmosphere and other places, I was discussing amounts of CO2, not the identical CO2 molecules. It would technically be more correct to say that the net CO2 accumulation in the atmosphere and the upper ocean, etc, has been caused by emissions. The distinction is that the actual molecules get redistributed by CO2 fluxes, some of which are quite rapid, but the net accumulations are determined by imbalances.
My understanding is that for each unit of emission of CO2 into the atmosphere at one time, there is some initial drawdown that is rapid, removing perhaps half or a bit more of that addition and transfering it to the upper ocean and to land organic C (via CO2 fertilization). I’d expect this initial drawdown occurs on the timescale of the residence time of CO2 molecules in the atmosphere. The residence time is the amount in a reservoir divided by the flux out of the reservoir (this doesn’t mean all molecules in the reservoir at an initial time leave the resevoir over one residence time; rather, for a well-mixed reservoir such as the atmosphere, the number of molecules remaining exponentially decays on that time scale, while for the deep ocean, there may be a somewhat less random clustering of times spent by each molecule depending on ocean currents, but the idea either way is that the residence time is an average).
This initial drawdown approaches some equilibrium among the atmosphere and ocean at least, but this doesn’t correspond to the same percent increase in both because CO2 doesn’t simply go into the ocean as a dissolved gas and the total oceanic C uptake is limited by other factors.
The remaining accumulation in the atmosphere remains considerably longer however, so that the perturbation timescale for CO2 amount is considerably longer than the residence time of CO2 molecules in the atmosphere.
From the C-cycle link in this webside ( http://carboncycle.aos.wisc.edu/ ):
Residence times of CO2:
Columns:
1 reservoir
2 preindustrial, years
3 % change since preindustrial,
4 % change since preindustrial excluding anthropogenic forcing (land-use changes, but not accounting for the portion of land uptake that is anthropogenically forced (ie reforestation, N-cycle changes – these are left in).
atmosphere ___________________:_____ 3.14 __|_ 12.2
vegetation, soil, and detritus____:___ 19.2 ____|_ -2.3 _____|__ -1.7
surface ocean _________________:______ 4.27 _|__ 2.6
marine biota __________________:______ 0.06 _|
All of the above as one reservoir:_____ 37.5 __|__ 4.8
intermediate and deep ocean __:____ 367 ___|__ 0.27
All of the above as one reservoir: approx. 200,000 ____|__ 0.84
(note this doesn’t include the carbonate weathering feedback to anthropogenic climate change)
“(note this doesn’t include the carbonate weathering feedback to anthropogenic climate change)”
That would only be important (if it is important) to the residence time of C in the combined reservoir (atmosphere + vegetation,soil,detritus + marine biota + surface ocean + intermediate and deep ocean).
Peter Ridley said:
“It look’s like it’s going to be another bitterly cold winter this year, even worse than last, which was bad enough. ”
And what relevance does this have??
It seems that you arrogantly make some statements that had some scientific interest and maybe some merit, then you wander into some bull about weather or the seasons of the hemispheres???
It happened to be a warm October in the UK this year. But that is just as irrelevant as pointing out that December is cold this year.
SI, in the humble opinion of Chris Colose and Patrick 027 I should ignore the opinions of Robert Essenhigh (Note 1) and Professor William M. Gray (Note 2) and pay attention to their own scientific interpretations. Let us take a look at the scientific pedigree of these four.
1) Chris Colose, who is QUOTE: .. a 21-year old college student pursuing an Atmospheric and Oceanic Science degree. UNQUOTE *
2) Patrick 027, who has a QUOTE: degree in .. atmospheric/oceanic science …UNQUOTE but who claims to QUOTE: .. standing on the shoulders of giants .. UNQUOTE.
* with no published peer-reviewed papers of any sort relating to any one of the many disciplines involved in developing an understanding of climate processes and drivers.
3) Robert Essenhigh, Professor of Energy Conversion, Dept. of Mechanical Engineering, The Ohio State University (PhD 1959, Fuel Technology and Chemical Engineering) has QUOTE: .. over 45 peer-reviewed research articles mainly in the area of combustion .. UNQUOTE (Note 3) resulting from many years of research ranging through QUOTE: heterogeneous reaction kinetics …. solid waste disposal; air pollution, and formation and control of pollutants UNQUOTE.
4) Professor William M. Gray (Ph.D. 1964 University of Chicago, Dept. of Geophysical Sciences) QUOTE: .. over 80 published papers and 60 more extensive research reports. Hundreds of Conference talks and conference proceedings. UNQUOTE.
Patrick 027, don’t insult the memory of Sir Isaac Newton. You don’t even reach up to the ankles of those “giants”. Enough said!
NOTES:
1) see http://www.mecheng.osu.edu/people/robert-essenhigh
2) see http://www.kevinlundberg.com/TheIssues/GlobalWarming/Index.html
3) see http://www.desmogblog.com/robert-h-essenhigh
Have a great 2010. Regards, Pete Ridley, Human-made global climate change agos(cep)tic
Response– And yet they remain wrong about water vapor in the atmosphere– chris
Re Pete Ridley – I’d wager the giants whose shoulders I stand on – okay, maybe I should say I’ve only climbed up as far as (? this analogy is getting awkward) – but from wherever I am I can see clear over the heads of Singer and Essenhigh regarding the C cycle and radiative forcing and the water vapor feedback.
Why should this be surprising. Look at the qualifications you give for Essenhigh. What insight would that give Essenhigh into matters of climate science?
Pete Ridley, I’m not challenging Essenhigh on the process of combustion. And if we aren’t allowed to intellectually benifit from other’s work, why are you even bringing other’s opinions and descriptions up – shouldn’t you be doing your own work?
Admittedly, I haven’t cited much (but have done a few).
Well, see my comment here: https://chriscolose.wordpress.com/2008/12/10/an-update-to-kiehl-and-trenberth-1997/#comment-1122 , where I list a fair number of college-level textbooks. You could also try looking at the Encyclopedia Brittanica macropedia entry “climate and weather”. Etc.
In as far as the C cycle is concerned, see here (still waiting for response), and note link to work by David Archer, who also has a book… –
http://www.realclimate.org/index.php/archives/2009/12/unforced-variations/comment-page-21/#comment-151663
More about your and Robert Taguchi’s prior questions about tropospheric inversions later (I didn’t forget).
Chris, in checking up on Assistant Professor McKinley’s pedigree I came across an interesting June 2007 article on the madison.com site (Note 1) operated by Capital Newspapers, publishers of the Wisconsin State Journal. This discusses McKinley’s disagreement with U of Wisconson – Madison professor emeritus Reid Bryson.
QUOTE:
.. the founding chairman of the department of meteorology at UW-Madison… known as the father of scientific climatology, considers global warming a bunch of hooey. .. Just because almost all of the scientific community believes in man-made global warming proves absolutely nothing, Bryson said. “Consensus doesn’t prove anything, in science or anywhere else, except in democracy, maybe.” .. There is no question the earth has been warming. It is coming out of the “Little Ice Age,” he said .. “However, there is no credible evidence that it is due to mankind and carbon dioxide. We’ve been coming out of a Little Ice Age for 300 years. We have not been making very much carbon dioxide for 300 years. It’s been warming up for a long time,” … The Little Ice Age was driven by volcanic activity. That settled down so it is getting warmer, he said. Humans are polluting the air and adding carbon dioxide to the atmosphere, but the effect is tiny, Bryson said. “It’s like there is an elephant charging in and you worry about the fact that there is a fly sitting on its head. It’s just a total misplacement of emphasis,” he said. “It really isn’t science because there’s no really good scientific evidence.” Just because almost all of the scientific community believes in man-made global warming proves absolutely nothing, Bryson said. “Consensus doesn’t prove anything, in science or anywhere else, except in democracy, maybe.”
So, if global warming isn’t such a burning issue, why are thousands thousands of scientists so concerned about it? “Why are so many thousands not concerned about it?” Bryson shot back. “There is a lot of money to be made in this,” he added. “If you want to be an eminent scientist you have to have a lot of grad students and a lot of grants. You can’t get grants unless you say, ‘Oh global warming, yes, yes, carbon dioxide.'”
Not so fast, say scientists: Galen McKinley, an assistant professor of atmospheric and oceanic sciences at UW-Madison disagrees with Bryson, whom she notes is a respected researcher and professor with a long history at the university. .. Carbon dioxide emissions have been increasing over the industrial period, about 200 years, and can be observed very clearly through about 100 monitoring stations worldwide, McKinley said. The concentration of carbon dioxide in the atmosphere is increasing consistently with the amount that humans are putting into the atmosphere, she said. “We know humans are putting it there, we understand the basic mechanism and we know that the temperatures are warming. Many, many, many studies illustrate that both at the global scale and at the regional scale.” ..
The huge changes in temperature that scientists are seeing are happening much faster than have ever been observed in the past due to the change from an Ice Age phase to a non-Ice Age phase, she said. “We know that humans are putting CO2 into the atmosphere at an incredibly fast rate, much, much faster than any natural process has done it in the last at least 400,000 years and probably more like millions of years.”
UNQUOTE
Just a moment, let’s go back to the McKinley page you linked to, which provides a link to the “Carbon Cycle” page (Note 2). Looking at that IPCC AR4 extract about it appears that QUOTE: .. the major fluxes in GtC/yr .. best estimates for the 1990’s .. UNQUOTE for:human-caused CO2 into the atmosphere (ignoring breathing) is
.. fossil fuels ……. 6.4
.. surface ocean …20
.. land use change .. 1.6
UNQUOTE. i.e. human-caused CO2 into the atmosphere is 28 GtC/yr, whereas for QUOTE: … pre-industrial ‘natural’ fluxes ..
.. respiration ….. 119.6
.. surface ocean .. 70.6
UNQUOTE, i.e. natural CO2 into the atmosphere is 190.2 GtC/yr.
Does this not indicate that nature puts CO2 into the atmosphere at a far greater rate than humans (190.2 GtC/yr v 28 GtC/yr)? I make that less than 15% of the CO2 going into the atmosphere is caused by humans, with only about 3% being due to our use of fossil fuels. This does not align with McKinley’s “We know that humans are putting CO2 into the atmosphere at an incredibly fast rate, much, much faster than any natural process has done it in the last at least 400,000 years and probably more like millions of years”. So I’m obviously doing my sums wrong here. Can someone explain to me where I’ve gone wrong? – otherwise I’m going to have to continue being persuaded by Professor Bryson’s sceptical arguments.
That article concludes that McKinley said QUOTE: “The scientific process is never 100 percent sure and it could be proven wrong,” McKinley added. “But I would say that the chances of that based on all of the
best information at this current time are incredibly slim. And even though that possibility is out there, it would be irresponsible of us as a society not to act based on the best scientific information we have at the moment, which is that humans are causing the warming of the planet,” she said. “If you saw smoke in your house, it would be irresponsible not to get your family out, right?” UNQUOTE. Well, if that smoke was coming from a candle that my wife had just lit up then I would feel like a proper twit when the fire brigade turned up!
That article is well worth reading. You may also be interested in looking at an A/V of an excellent 2007 debate on “Global Warming is not a Crisis” (Note 3) facilitated by Brian Lehrer, WNYC involving Chrichton (it’s a shame that he’s no longer with us), Richard Lindzen and Philip Stott (for the motion) versus Brenda Ekwurzel, Gavin Schmidt and Richard Somerville (against). It was also interesting to see the swing in audience opinion as a result of the debate – from 30% for v 67% against to 46% for v 42 against, i.e. following open debate of both sides of the issue, many more people come to realise that there is no crisis ahead!
Other A/Vs on that page are worth looking at.
NOTES:
1) see http://www.debunkers.org/Library/files/block_0/GlobalWarmingHooey.pdf
2) see http://carboncycle.aos.wisc.edu/global-carbon-cycle/
3) see http://www.youtube.com/watch?v=Fz8KiA-YMt8&NR=1
Regards, Pete Ridley, Human-made global climate change agos(cep)tic
PS: is no-one able to help me understand about that preferential fractionation thingey within those ice sheets and glaciers? I raised this on Chris’s “Richard Alley at AGU 2009: The Biggest Control Knob” at https://chriscolose.wordpress.com/2009/12/18/richard-alley-at-agu-2009-the-biggest-control-knob/#comment-1448 but no-one has responded. Come on you scientists, please help me out.
Happy and healthy 2010 to you all.
Pete R
PPS: Oh dear, I missed out an important point that is also puzzling me about the significance of our emissions of CO2. In that IPCC AR4 diagram (see Note 2 above) it says QUOTE: Gross fluxes generally have uncertainties of more than ±20% UNQUOTE. Does not this mean that the contribution that our use of fossil fuels makes is swamped by the uncertainties? Maybe it’s the celebrations last night preventing me thinking clearly.
“following open debate of both sides of the issue, many more people come to realise that there is no crisis ahead!”
Hey, but didn’t you post this:
”
Just because almost all of the scientific community believes in man-made global warming proves absolutely nothing, Bryson said. “Consensus doesn’t prove anything, in science or anywhere else, except in democracy, maybe.”
”
Scientists don’t reach consensus because they just wake up one day and decide to vote that way; they reach consensus because they’ve been swayed by the strength of the evidence and the logic of the theory.
And of the non-climate scientists who are swayed by a debate, what qualifications do they have to make such a decision**? You wanted to know mine, wouldn’t you like to know their’s?
A debate often is not about getting to the truth or seperating fact from fiction, it often takes the form of persuasion by any means necessary, including obfuscation and, as Sarah Palin would say, just making stuff up. If one party in a debat is being honest and another party is being dishonest and has practiced, how would an audience know? Or, more innocently (because I’m not going to claim to know whether certain people realize they are wrong or not), if one party is accurate and logical and one party is innaccurate and illogical, how is an audience which lacks sufficient background information and attention to logical detail supposed to be able to recognize the difference?
**(Anyone can have an opinion. You have a right to believe that clouds are made of fairy dust. (And I have a right to say that you would be wrong.) I’m really not trying to restrict your freedom of belief. But when you pay the bills, you don’t get to pay according to how much you ‘believe’ you owe.)
________
“Well, if that smoke was coming from a candle that my wife had just lit up then I would feel like a proper twit when the fire brigade turned up!”
Sure, so would you feel like a proper twit when you call the fire brigade in to put out the flames of innaccuracy in climate science when in fact the smoke was just from a few contrarians having cigars?
——-
“So I’m obviously doing my sums wrong here. Can someone explain to me where I’ve gone wrong? – otherwise I’m going to have to continue being persuaded by Professor Bryson’s sceptical arguments.”
First, I don’t think Bryson’s argument necessarily had anything to due with the cause of recent atmospheric CO2 level changes (which, remember, were nearly steady for thousands of years before the industrial revolution, and during the last deglaciation, increased far more slowly than the recent changes.).
Second, see any of what I previously wrote in respone to you regarding the C cycle.
To a good approximation, nearly 100 % of the recent ~ 100 ppm increase in CO2 in the atmosphere, plus accumulation of C in the ocean, and net depletion of organic C on land, is due to anthropogenic effects.
——–
Reid Bryson’s take on the unimportance of anthropogenic global warming appears to be some combination of:
1. lower climate sensitivity
and/or
2. larger centennial-millenial scale internal and naturally-forced variability.
and/or
3. climate is no big deal to anything much (?)
Well, although there is wiggle room (how much room I actually don’t know) for different spatial-temporal patterns involved in some internal variability and the more idiosyncratic forced changes (this doensn’t include solar forcing so far as I know), (and wherein significant regional effects could accompany variations with smaller global average temperature changes)… but
generally, larger variations in the past should tend to require higher climate sensitivity for the same forcings or for larger internal variability. Solar forcing variation estimates just are not that large for the little ice age. Some volcanic forcing variation too, but again, for ~ 0.5 to 1 K/(W/m2 forcing) climate sensitivity, is it combined with solar forcing enough to expect forced climate variations as large as 20th-early21st century warming thus far (? I’d be interested to see if you can show me that the answer could be yes; I think it is no.), and bear in mind the reasonably-expected change if we continue on the way to doubling or more the atmospheric CO2 level.
We have paleoclimatic data, historical records, evidence for past forcing levels, and a knowledge of physics. I don’t see how it’s possible for anthropogenic CO2 and other climate-change emissions not to have a substantial effect of the sort which is cause for serious concern.
Back to the candle analogy, regarding policy implications –
Would you buy car insurance if there is a 1% chance over a year that you’ll be involved in an accident?
Well, consider how much more you’d pay for insurance (if you continue to use a car) if there was a 90 % chance of being in an accident.
It just doesn’t make sense in general to require 100 % certainty to justifify action. What if we applied the same wait-and-see approach thus far used in response to the anthropogenic climate change threat for other matters. Where would we be if we decided not to due much to reduce the spread of HIV and treat the virus if we waited for that remaining person to decide that it is the cause of AIDS? If we refused to get vaccinated until we knew for sure that we would be the people who would otherwise contract a disease. If we never invested in money or time or effort at all in anything (there would be no food)? If most of us (not the ones who are actually terminally-ill) didn’t go to school because of the chance that we could die before recieving the benifits?
… Re –
“3. climate is no big deal to anything much (?)”
Well, I actually have evidence that this can’t possibly be Reid Bryson’s position. I was just holding it in my hand about 1 minute ago (from typing this line, not necessarily from the time I clicked on “Submit Comment”):
Reid A. Bryson and Thomas J. Murray.
“Climates of Hunger – Mankind and the world’s changing weather”. 1977.
Now I have to admit that I haven’t yet read the book, though I have read a brief review of the history of (largely natural, presumably) climate variations and their serious effects on human civilizations in none-other-than “Earth in the Balance” by Al Gore – now, lest you think this is ‘where I’m coming from’, bear in mind I have also studied using most of the textbooks I listed at https://chriscolose.wordpress.com/2008/12/10/an-update-to-kiehl-and-trenberth-1997/#comment-1122, and various other sources; frankly the time that has passed between my last signficant reading in a book by Al Gore and the first comment I ever posted at a blog is a few years.
But I will now put this (Bryson and Murray) and specifically the section of Ruddiman on millenial-scale climate variability back on my reading list.
From Bryson/Murray:
Prologue:
p.xi:
“In 1973 an international group of scientists wrote to the President”…”and they could see from the rhythm of past ice ages the possibility of another ice age within centuries, and almost positively within a few millenia. There is no imminent danger of a new continental ice sheet like the one that existed more than 10,000 years ago from the Arctic to the Great Lake and
(to be continued, but for this part, note that, while the event of that writing the President took place (I assume), it did not reflect a scientific consensus – there was never a consensus of imminent global cooling, and the potential of anthropogenic global warming was at that time being seriously studied; it is now understood that not all interglacials are so short and the next ice age, if we don’t prevent it, may not occur for tens of thousands of years, perhaps for 50,000 years.)
(continued)
…”from the Arctic to the Great Lakes and the Atlantic to the Pacific. These take millenia to grow- although we should not ignore changes on that time scale, because we are building dams and nuclear waste facilities with planned life-times of centuries and longer.”
“But climatic changes preceding the formation of such ice sheets are also extremely important, as are the fluctuations that occur throughout unglaciated times.”
a few other quotes:
pp. xi-xii:
(refering to the time between 1972 and this book) “During these years we have seen drought in the Sahel and in Central America, severe frost damage to Brazilian coffee, poor monsoons in South Asia,”…”the winter of 1977, with record cold in the midwestern and eastern United States, snow in southern Florida [this was before The Weather Channel’s “Guaranteed White Christmas” contest], and a continuing drought in the Great Plains and the West, emphasizing again the effects of climate on human activity.”
“Many of our food crops are very well adapted to the climate under which they are grown-for example, corn. This means that the best yield is obtained undeer climatic conditions like those of the recent past (often called “normal” climate). Any departure from “normal” brings a lower yield; any fluctuation is adverse for such well-adapted crops.”
and
“We should not think of the climate and weather of our lifetimes as an unchanging “normal.””
“Climate not only varies year by year but can change rapidly to a new multi-year average.”
“The climate, once changed, can stay changed for long periods of time. Within the last thousand years there has been a 200-year drought in the United States corn and spring wheat belt.”
p.xiii
“Records of past climates also show that those times in earth history when temperatures in high latitudes have been lower, have generally been times of greater weather extremes and erratic or absent monsoon rains in Asia. These would affect United States domestic and foreign policy as well as the people in those lands.”
“We cannot predict with certainty the shape of the climatic future. But then decision-makers rarely have the advantage of precise foresight. Any policy is an effort to make the most of the future, with all its unknowns.”
“Even climatic fluctuations that appear to be small in size can be significant economically. Our research at the University of Wisconsin-Madison shows that an increase of [ 1 deg C or 1.8 deg F ] in the summer temperatures in the northern plains can reduce the gross dollar income of the spring wheat farmers by $131 million, and a modest 20 percent shortfall of precipitation can cost another $137 million.”
There is an irony, I think, in how this next part is worded (my emphasis added):
“Climate variation, like death and taxes, is certain. We know of no century with constant climate. BUT A MORE IMPORTANT QUESTION is whether the climate will be APPROXIMATELY like that to which our activities have been adapted or whether we will be dealing with a MAJOR climatic shift.”
———–
Of course, science has advanced since 1977, but I don’t see any errors, so far as I know, at least in those parts I quoted, and wouldn’t generally assume the book contains big errors.
The points I will add:
1.
I’m not sure of greater variability of climate during colder periods is found in general over the globe or is concentrated in some regions; or for that matter, I wouldn’t assume that an overall warmer climate leads to reduced variability. Variability takes different forms. There may be variability in week-to-week, month-to-month temperature and rainfall. There may be gentle rain vs flash flooding. There are intraseasonal-interannual variations.
The monsoons in Asia obviously could not have been erratic before Asia existed.
I’ve gotten the impression that some of the glacial variability is specifically associated with pulsations of meltwater flow into the ocean from the Laurentide ice sheet, which we no longer have.
2.
A drought may be more or less severe than another. A storm track can shift more or less. A pattern of circulation can shift to varying degrees. Not to say that everything can be linearly superimposed, but even given some significant natural regional climate variations that can be expected to occur in general (perhaps without predictability of specific timings and intensities of specific episodes), this doesn’t mean that the regional effects associated with a forced big global average temperature change are not important. Unless the potential for change has been saturated, there is room for more change. We could get lucky at some times have natural floods on top of anthropogenic droughts, or we could get unlucky at times and have natural droughts on top of anthropogenic droughts.
Speculative, but interesting point: If the costliness of a variation increases more rapidly than linearly with the variation, than variations that average to zero superimposed on some average change will be on average more costly than the variations about an unshifted average by themselves.
To what extent do natural fluctuations in agricultural productivity tend to average out around the globe? (Not saying that this can’t happen naturally (it does, but time scale might be different **), but if the storm tracks shift poleward so that the subtropical dry belts generally introde into midlatitude farmlands, that would tend to be a global problem.)
“frankly the time that has passed between my last signficant reading in a book by Al Gore and the first comment I ever posted at a blog is a few years.”
The point being that I am not basing my comments on information from Al Gore.
Which was not to dump on Al Gore. I think Al Gore has done good work. Although I was embarrassed for him when I heard of the ‘million degrees down there’ debacle – but I suspect Al Gore is better educated about climate science than about geology.
——
The climatic fluctuations within the Holocene are something I haven’t studied in much depth.
In elementary school the desertification of the Sahara was explained by land use, but I have since learned that the Sahara was simply a wetter place 10,000 years ago or so – not that this is independent of vegetation – there is a vegetation feedback on rainfall patterns – but my understanding is that wet-dry variations in the Sahara are part of a pattern that has probably been forced by the ~ 20,000 precession cycle modulated by the ~ 100,000 year eccentricity cycle.
Other things I don’t know as much about.
But, in an indirect sort of way, I suspect that the regional effects expected from a few K of global warming are large enough compared to the regional variability associated with internal variability, etc, because there is concern of mass extinction (I would think at least a portion of which is not due to sea level rise or ocean acidification (two things that are not a big risk from natural climate variability); how big were any spikes in extinction rates during the Holocene, or during the entire Quaternary (older term, I know), for that matter?
(why wouldn’t ~ 5 or 6 or so K swings cause mass extinctions between glacials and interglacials? Perhaps because the first ice ages were less intense than the later ones, and life had time to adapt to global temperature fluctuations within the glacial-interglacial range? Perhaps because the changes were relatively slow…)
Well, not knowing offhand the relationship, some generalities:
For any regional climate dimension:
If we measure the range of natural variability as y, where y is proportional to some typical deviation from a longer-term average (perhaps y = k*standard deviation, where k = ?)
Where the prior average is used as a baseline, value 0.
And if the change from a global warming is x,
then, if y is not itself a function of x and the costs of dealing with climate change are linearly proportional to change,
Then an |x| 0 (x y suggests that both x+y and x-y conditions fall on the same side of zero, so that further increases in |x| require additional adaption to both x+y and x-y conditions, thus being a net cost.
BUT
1a.
If the cost of variation (var) from 0 is proportional to var^r, where r > 1, then there could be a net increase in cost for any increase in |x| even when |x| < y, because the decreased variation from 0 of one sign has less benifit than the cost of the increased variation from 0 of the other sign.
1b.
the costs of +y and -y could be different even if x=0, and also, the distribution of natural variability might not be symmetrical about 0.
2.
If we are to some extent prepared for the the range of conditions -y to y, then any nonzero |x| will devalue some of that preparation and require additional preparation for the the extremes in conditions of the same sign as x.
3a.
y could be a function of x. This could increase or decrease the net cost of an x, depending…
3b.
Of all the regional climatic variables that have such variations, y could change in different ways as a function of x for different variables on different timescales – in other words, the overall shape of natural variability could change, which (See point 2 above) would require adaptation not just to a new average but to changes in natural variability, even if an economically-weighted average y for all dimensions of variability were to stay the same or even decrease – though this is not so true if we have yet to prepare for any natural variability.
4.
if there is uncertainty in climate senstivity as defined by x/forcing, then there is a range of possible x values for a given anthropogenic forcing, which tends to increase for larger forcings. This will add to costs of increases in expected |x| values by way of increasing the potential difference between expected x and actual x.
——-
Some of that didn’t seem to come out right: Attempted redo
Then an
|x| less than y
suggests that the increased costs of conditions for when x and y are the same sign could be balanced by a decreased cost of conditions when x and y are opposite signs.
Whereas an
|x| greater than y suggests that both x+y and x-y conditions fall on the same side of zero, so that further increases in |x| require additional adaption to both x+y and x-y conditions, thus being a net cost.
BobFJ – I must thank you for that manual; I always figured there must be such a manual out there but never found it myself – once upon a time there was a blog that came with some such instructions but I didn’t pay much attention to it at the time.
Sorry, that was intended for another thread…
to patrick027 and others
DO NOT GIVE PETE RIDLEY PERSONAL INFORMATION ABOUT YOURSELF
Nice sharing though I am still confusing to figure it out