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Unforced Varations: Aug 2012

Filed under: — group @ 2 August 2012

Once more with feeling…


571 Responses to “Unforced Varations: Aug 2012”

  1. 1
  2. 2
  3. 3
    Pete Dunkelberg says:

    Temperatures of the instrumental period graphed easily by Kevin C.
    http://skepticalscience.com/watts_new_paper_critique.html

  4. 4
  5. 5
    David B. Benson says:

    Pete Dunkelberg @2 — I found the piece well balanced. The problem is there simply is not enough suitable coastline to make much of a CO2 impact. For the requisite scale, read
    Irrigated afforestation of the Sahara and Australian Outback to end global warming
    http://www.springerlink.com/content/55436u2122u77525/
    wherein the link to the full paper is free for everybody.

  6. 6
    Brian Dodge says:

    Re BEST/WUWT kerfuffle -

    http://www.internationalclownweek.org/ – “Our purpose is to celebrate, promote, and inform on International Clown Week, the First week in August, every year.” Ah, NOW I understand.

  7. 7
    don gisselbeck says:

    Professor Muller was interviewed on Democracy Now today http://m.democracynow.org/stories/12971 . Congratulations to him for catching up to late 20th century climate science and the data analysis skills of a good dozen bloggers. He sounded like one of those people who show up on a backcountry ski trip and start lecturing the guide about avalanches. I can’t imagine him finding this classic funny; http://xkcd.com/793/

  8. 8
    Chris Colose says:

    While we’re all posting links, I’ll post my own article on the water vapor feedback…enjoy

  9. 9
    Kevin C says:

    Pete Dunkelberg: Thanks! I couldn’t have done it without Caerbannog’s clear description of the common anomaly method, which I think he got from one of Tamino’s lost posts.

    65 lines of code can probably be beaten though. May I suggest a competition?

    (Suggested rules: Any language. Using purpose-built libraries, such as Steve Mosher’s R library, is cheating. General purpose libraries such as SciPy are fine. Special category for long-dead languages such as APL or 6502.)

  10. 10
    Pete Best says:

    http://www.democracynow.org/2012/8/2/climate_skeptic_koch_funded_scientist_richard

    Is Muller characterising Mann unfairly where he is mentioned in ths Democracy Now video or is he just a Professor who went to the press first and awaits peer review second for some other reason? Is he following te right way of doing science here.

    Although he now appears to accept Global Warming as fact where he did not before and his BEST study uses data going back to the 1750s and involves statistical techniques deployed by Saul Permutter (Universe expansing physcist) and others he is still questioning wether certain weather events can be attributed to ACC/AGW at all!? I have seen recently that some papers and comments here and other places have stated that the odds of the European 2003 heatwave and the 2010 Russian one were statistically more likely with 100 ppmv of C02 added to the atmosphere than before it was so is Muller still stalling here?

    Its all damm intruiging but where does climate science stand on this work and claims please

    [Response:By my count, Muller told at least 8 fibs in that interview (including false statements he made about me and my work). Please see either my Facebook page (http://www.facebook.com/MichaelMannScientist) or twitter feed (@MichaelEMann) for further details. Thanks. --mike]

  11. 11
    Kevin C says:

    The BEST team have posted a temperature reconstruction for Antarctica:
    http://berkeleyearth.lbl.gov/regions/antarctica
    (Unfortunately no gridded data, but someone with MATLAB-fu might be able to generate one.)

    How does this compare with the Steig and O’Donnel results?

    [Response:The mean trends are directly comparable to Steig et al, and about twice that of O’Donnell et al. That’s satisfying to me of course, but it would be interesting to know whether they have any additional data we didn’t have; if not, then I wouldn’t put much weight on it. In any case, O’Donnell et al. has already been shown to be quite wrong, by independent borehole T data — see the brief write-up we did, here.–eric

  12. 12
    Icarus62 says:

    Suppose we decide that the only safe target for atmospheric CO2 is 280ppm – the pre-industrial level. We aim to sequester the existing ~110ppm of additional CO2, plus whatever we produce from industry, transport etc. in coming decades, plus whatever comes out of the warming oceans and other carbon sinks. Basically we want to recover all of the ~1.2 trillion tons of CO2 we’ve put into the atmosphere in the last 250 years.

    My question is: Do the laws of physics dictate that this process requires as much energy to achieve it as we gained by burning all that carbon in the first place? Are there ways to ‘cheat’ and convert the CO2 into some kind of stable form using far less energy than we gained during its production? I know that the biosphere can help us, as it already has done, by using photosynthesis to draw down CO2, but if we’re going to encourage that, we still have to convert the biomass to some inert form (biochar?) to stop it decomposing and returning the carbon to the atmosphere. Presumably harvesting and processing that biomass will require considerable energy in itself.

    What’s likely to be the least energy-intensive way of recovering a large amount of CO2 from the atmosphere?

  13. 13

    A promised update: my “summary review” article on “The Hockey Stick And The Climate Wars” is once again available; apologies to any who may have gone looking while it was in limbo. (It got yanked as a ‘duplicate’ by the publisher, due to an unauthorized (and unattributed) repost. But now, though the repost remains, the original is ‘certified original,’ and back up online.)

    Enough of that–link:

    http://doc-snow.hubpages.com/hub/Michael-Manns-The-Hockey-Stick-And-The-Climate-Wars-A-Summary-Review

  14. 14
    Pete Dunkelberg says:

    Keven C @ 9
    “65 lines of code can probably be beaten though.”

    Clearly, since much of it is comments. But that’s a good thing.

    I think this should become a whole separate post at Skeptical Science.

    David Benson @5, thanks for that input.

    don gisselbeck @7 and all, also see this remark by cro magnon at tamino’s
    http://tamino.wordpress.com/2012/08/01/much-ado-about-nothing/#comment-65035

    I don’t know what’s up with Muller but the matter bears watching.

  15. 15
    Chris Dudley says:

    Andy Revkin pointed me to this article linking very high sea surface temperatures in 2010 to the heatwave and flooding in Urasia that year.

    Climate extremes and climate change: The Russian Heat Wave and other Climate Extremes of 2010 by Kevin E Trenberth and John Fasullo

    Abstract:

    A global perspective is developed on a number of high impact climate extremes in 2010 through diagnostic studies of the anomalies, diabatic heating, and global energy and water cycles that demonstrate relationships among variables and across events. Natural variability, especially ENSO, and global warming from human influences together resulted in very high sea surface temperatures (SSTs) in several places that played a vital role in subsequent developments. Record high SSTs in the Northern Indian Ocean in May 2010, the Gulf of Mexico in August 2010, the Caribbean in September 2010, and north of Australia in December 2010 provided a source of unusually abundant atmospheric moisture for nearby monsoon rains and flooding in Pakistan, Colombia, and Queensland. The resulting anomalous diabatic heating in the northern Indian and tropical Atlantic Oceans altered the atmospheric circulation by forcing quasi-stationary Rossby waves and altering monsoons. The anomalous monsoonal circulations had direct links to higher latitudes: from Southeast Asia to southern Russia, and from Colombia to Brazil. Strong convection in the tropical Atlantic in northern summer 2010 was associated with a Rossby wavetrain that extended into Europe creating anomalous cyclonic conditions over the Mediterranean area while normal anticyclonic conditions shifted downstream where they likely interacted with an anomalously strong monsoon circulation, helping to support the persistent atmospheric anticyclonic regime. This set the stage for the “blocking” anticyclone and associated Russian heat wave and wild fires. Attribution is limited by shortcomings in models in replicating monsoons, teleconnections and blocking.

    Andy considers this evidence that attribution is not coming together. The success of the approach of Hansen et al. http://arxiv.org/abs/1204.1286 would seem to argue against that interpretation.

  16. 16
    Chris Dudley says:

    Icarus62 #11,

    The brightness temperature of the night sky in Antarctica is low enough to allow carbon dioxide to be frozen out of the atmosphere using mirrors to shield from the ground temperature. So, hardly any energy is needed to remove carbon dioxide. But, it is unlikely to stay sable in that form for long enough.

  17. 17
    John E. Pearson says:

    8 Chris: Thanks for that article.

  18. 18
    John E. Pearson says:

    12 Icarus on sequestration:

    Google for Klaus Lackner. Geosequestration requires less energy than was obtained from the fossil fuels in the first place.

    http://www.earth.columbia.edu/articles/view/2523/

  19. 19
    John E. Pearson says:

    10: There isn’t a right way of doing science that dictates when a scientist should report his results to the press. In the VAST majority of cases the press will not be interested in any case. Most journals do not send out press releases on new papers either. “High Profile” journals like Science, Nature, Cell, PNAS, and a few others do, but mainly that isn’t done. There are far too many scientific papers published for them all to be of interest to the media. Indeed I believe that the majority of scientific papers aren’t even of interest to other scientists but I might be off a little on that.

  20. 20
    Hank Roberts says:

    Comparing Muller on Forum with Muller on DN, the talking points do emerge rather starkly, don’t they?

    I suppose “clean fracking” is the replacement for “clean coal” from the talking point crafters.

    “Anything but the IPCC.”

  21. 21
    muoncounter says:

    Anyone remember last year’s CLOUD kerfuffle?

    Update: The neutron monitor database at Oulu, Finland shows that cosmic ray counts have decreased ~12% since their peak in May-December, 2009. That’s a significant decrease; under the ‘it’s cosmic rays’ hypothesis, cloud fraction should be on its way down.

    It isn’t. Cloud fraction data are available in CSV form here. Compare, for example, July 2009 and July 2012. No statistically significant changes noted. Once again, with feeling: It’s not cosmic rays.

    I guess with all the other things deniers are busy backtracking on these days, this slipped through the cracks in their arguments.

  22. 22
    SecularAnimist says:

    Icarus62 wrote: “What’s likely to be the least energy-intensive way of recovering a large amount of CO2 from the atmosphere?”

    Organic agriculture and reforestation.

  23. 23
    Anonymous Coward says:

    @Icarus62 (#12),
    “Do the laws of physics dictate that this process requires as much energy to achieve it as we gained by burning all that carbon in the first place? Are there ways to ‘cheat’ and convert the CO2 into some kind of stable form using far less energy than we gained during its production?”
    There are chemical reactions which use up CO2. Strictly speaking, they don’t require energy (at naturally-occuring temperatures anyway). But getting the right naturally-occuring molecules in contact with atmospheric or oceanic CO2 (or its byproducts) would require energy in practice, as would producing molecules especially for the purpose. These reactions can also be slow.
    There’s lots of litterature on this and some geoengineering proposals are being looked at. Check “Urey reaction” for instance.

  24. 24
    trrll says:

    Icarus62, the laws of physics tell us that if we sequester CO2 by converting it back into a reduced hydrocarbon, it will cost us as much energy (more, actually due to entropic cost) as we gained by burning it. But it does not prohibit us from sequestering the carbon in its oxidized form (i.e. as CO2). Alternatively, we could use solar energy to reduce the carbon and then store the biomass containing the reduced carbon compounds somewhere that it will not rapidly be re-oxidized into CO2. While this ends up using more energy than was gained by burning the fossil fuel, it is solar energy, so it does not add to atmospheric CO2. Basically, this could be seen as a roundabout and inefficient way of using solar energy, with energy costs at both ends. Of course, it would be more energy efficient if we could use the solar energy directly and leave the fossil fuel in the ground.

  25. 25
    Jeremy says:

    #7 – well if it’s linking comics about physicists week:

    http://www.smbc-comics.com/index.php?db=comics&id=2556

  26. 26
    Hank Roberts says:

    > the least energy-intensive way of
    > recovering a large amount of CO2

    The natural method appears to be extreme weather events causing greatly increased erosion, exposing unweathered rock that reacts chemically to bind some CO2, while extreme rainfall moves large amounts of surface material that gets washed into the oceans fertilizing blooms of organisms that die and settle out as sediment.

    Consider the US West where you can see huge erosion fans below many mountainsides formed the last time climate changed fast (end of the last ice age); most of them are not currently active and often have been built up with houses; those will become floods and landslides again (and zoning people are mostly aware of this).

    Probably it’ll be much more dramatic; look at the end of the PETM: http://www.wunderground.com/climate/PETM.asp

    This is scary; google for a full text and the illustrations, they’re out there: Abrupt increase in seasonal extreme precipitation at the Paleocene-Eocene boundary

    The only thing we seem to learn from paleoclimate studies is that we are unwilling to learn from paleoclimate studies.

  27. 27
    Unsettled Scientist says:

    Interesting paper coming out on the link between a warming climate and ozone loss in the stratosphere.

    UV Dosage Levels in Summer: Increased Risk of Ozone Loss from Convectively Injected Water Vapor

    The observed presence of water vapor convectively injected deep into the stratosphere over the United States fundamentally changes the catalytic chlorine/bromine free radical chemistry of the lower stratosphere by shifting total available inorganic chlorine into the catalytically active free-radical form, ClO. This chemical shift markedly affects total ozone loss rates and makes the catalytic system extraordinarily sensitive to convective injection into the mid-latitude lower stratosphere in summer. Were the intensity and frequency of convective injection to increase as a result of climate forcing by the continued addition of CO2 and CH4 to the atmosphere, increased risk of ozone loss and associated increases in UV dosage would follow.

    For those of us who lack access to Science, Science News is always a great resource and have coverage of this paper.

    Stronger storms may destroy ozone, Extra water vapor up high could trigger destructive chemical reactions

    “For 30 years, we’ve studied the problems of ozone loss and climate change separately,” says team leader James Anderson, a Harvard atmospheric scientist. “Now it’s pretty clear that climate change appears to be linked directly to the loss of ozone.”

    Anderson and his colleagues stumbled on the unexpected connection while studying strong summer storms fueled by rising heat. During missions from 2001 to 2007, NASA planes flying close to the edge of space spotted water spewed high into the sky by convective storms over the U.S. The goal was to gather useful measurements for figuring out how high-altitude clouds form and trap heat.

    [It's gotta be a lot of fun to fly in those planes. What a job!]

  28. 28
    Eric Rowland says:

    Hank Roberts @ 20 – I found Muller’s conversion as he called it in the NYT op-ed somewhat suspect but his reasons became more plausible as he’s trotted out the “clean fracking” advertizing slogan on various programs. Only time will tell if this is the first volley in a long term campaign to promote the benefits of fracking…I mean clean fracking.

  29. 29
    Hank Roberts says:

    > OZONE

    The abstract ends:
    “… Were the intensity and frequency of convective injection to increase as a result of climate forcing by the continued addition of CO2 and CH4 to the atmosphere, increased risk of ozone loss and associated increases in UV dosage would follow.”

    Editors, editors!

    The hypothetical conditional is meant to be used when “a future action or state is a consequence of some unlikely, hypothetical prior action or state”

    That phrasing is not meant to describe situations where you’ll get to where you’re headed if you find no way to stop.

    http://www.usingenglish.com/articles/conditional-sentences-in-english-4.html

    Shorter: oooooh, shit. Just talked to folks from New Zealand who already are getting way too much UV during normal daytimes.

  30. 30
    David B. Benson says:

    Icarus62 @12 — The least energetic way to remove the CO2 from the active carbon cycle is not necessarily the most efficient or effective. First, read the paper in the link I posted in an eariler comment. Second, to energize that process or one of several others, nuclear power plants might be more economic than solar PV (by most measures it currently is). Niether requires buring stuff so is low carbon.

    Another possibly is sequestering CO2 deep inside rock formations. This has not been tried, precisely, but in several locations the geology suggests this would result in fairly rapid mineral carbonization (permanent storage).

    Briefly, the techincal means are available. What is lacking is simply will.

  31. 31
    John e Pearson says:

    16 and 22 Dudley and trrl on sequestration:

    “Icarus62, the laws of physics tell us that if we sequester CO2 by converting it back into a reduced hydrocarbon, ”

    “So, hardly any energy is needed to remove carbon dioxide. But, it is unlikely to stay sable in that form for long enough.”

    These are sort of irrelevant versions of sequestration. Lackner’s proposal sounds plausible to this armchair dabbler.

    Google for Klaus Lackner. Geosequestration requires less energy than was obtained from the fossil fuels in the first place.

    http://www.earth.columbia.edu/articles/view/2523/

    David Archer once hinted that he’d do a thread on geoengineering. I assume he’ll discuss these points.

  32. 32
    Chris Dudley says:

    John #31,

    Some years ago I discussed that with Lackner and he described an idea for stabilizing ice sheet bases using dry ice. I was coming at the question on energy more from the perspective of disposing of nuclear waste, which if properly done through transmutation, would indeed cost as much or more energy as was derived in creating the waste. Nuclear energy is kind of not really energy at all if you have to pay it all back. For carbon dioxide, the removal part is, in principle, not an energy sink. Find some exposed serpentine in Antarctica and you could even build a heat engine using that and the carbon dioxide as fuel to produce carbonate ash.

  33. 33
    Thomas says:

    benson @30.
    I think it is more than simply will. I think it is energetically and financially feasible to enhance silicate weathering by breaking up near surface rocks with explosives. However given that many abandoned hard rock mining sites must be remediated to control heavy metals and other toxic materials, I doubt the environmental cost would be acceptable.

  34. 34
    Ron R. says:

    Eric Rowland — @ 1:45 PM

    I don’t like to look a gift horse in the mouth and hope this “conversion” was genuine, but if you notice the white piece of paper in the corner of the room to the right of the bookcase and above Muller and daughter’s heads you can see, now somewhat hidden, what apparently was Muller’s previous talking point.

    http://news.yahoo.com/blogs/lookout/former-climate-change-skeptic-now-says-global-warming-134617449.html

  35. 35
    Justin Daniel says:

    Any insight into the new Watts et al. paper on the surface station temperature data? I am 99.9% confident something really fishy is going on with it but I am not knowledgeable enough to know what.

  36. 36
  37. 37
    Edward Greisch says:

    Chris Dudley: “Nuclear energy is kind of not really energy at all if you have to pay it all back.”
    WRONG. And off limits. Leave it alone.

  38. 38
    Harmen says:

    Found this very informative video online..

    EGU2012: Climate change and the problem of climate sensitivity (PC11)
    2 aug 2012 EuroGeosciencesUnion

    Press Conference at the 2012 General Assembly of the European Geosciences Union. (Credit: EGU/CNTV.at)

    The European Geosciences Union (EGU, http://www.egu.eu/) is Europe’s premier geosciences union, dedicated to the pursuit of excellence in the Earth, planetary, and space sciences for the benefit of humanity, worldwide. It is a non-profit interdisciplinary learned association of scientists founded in 2002.
    ………
    http://www.youtube.com/watch?v=c9FOiPOSgu0

  39. 39
    Bobl says:

    MikeS@ 553 Unforced variation July Says
    Bobl, According to http://www.nrel.gov/csp/pdfs/32160.pdf, about 65 sq km is necessary for gigawatt (just under half your estimate). I’m not sure if that affects your claim (the authors of the report think solar is appropriate for baseline generation in much of the western US), but I thought I’d throw it out there.

    NREL is discussing thermal Solar (CSP) while we were talking about PV Solar, however as the NREL states, CSP solar doesn’t function with diffuse light, so they don’t derate properly for minimum insolation, thus the discussion assumes long term energy storage (which doesn’t exist at the moment) or backup generation to cover insolation gaps. So their 65 square km is not based on a “Reliable Baseload Equivalent Capacity” as my estimate is.

    Even assuming NREL numbers, 65 square km is a large area to carpet with mirrors for just 1 Gigawatt, The US installed capacity needs 1137 times this or 7605 Square km, little bit larger than the state of Delaware carpeted with mirrors (where nothing will live and birds will fry in the intense radiation fields) to replace current installed capacity, more if these is no backup.

    Horribly low energy density is the problem here. There is NO solution, NO waiting, Solar is a side game, and will always be a bit player in Energy, there just is no more than about 1000 Watts per square meter there to yield. The law of conservation of energy is your enemy and there is no prospect for bettering this unless you believe in fairies and perpetual motion

    Bob

  40. 40
    Pete Best says:

    Re #10 Why would a professor be so direct in his motivation to state that he has concerns regarding the science of climate when its all been examined and people exonnerated so many times?

    Was he offered money or does he have legitimate concerns and if he does why would he be making assertions about others people peere reviewed work? He makes little sense especially as he is saying that although ACC is real the actual events that have been linked to ACC (heat waves in Europe and Russia and perhaps the current one in the USA) are complete nonsense and then seems to be indicating that the USA is foolish to be doing anything about their emissions as China is the main one to blame.

    He has to be political in some sense surely ?

  41. 41
    Bobl says:

    I want to ask a serious question.

    I have been studying the feedback claims in the literature assuming a Nett gain of 3 over direct CO2 warming. I can’t see how that is remotely possible.

    This represents a loop gain in the climate system by the IPCC of 0.67 (in a linear system it would be 0.75). That’s practically impossible without gross instability. Not only this, we know there are large negative feedbacks operating in the climate (Direct Radiation to space, lapse rate) these Nett at a gain of about 0.2 (I understand from a Meteorologist I know), so that means that in the climate system there must be a Nett positive gain of about 15 (15 x 0.2) = 3. A Nett Positive feedback gain of 15 implies a positive feedback loop gain of over 0.9 and almost 0.95. That’s for all practical purposes impossible for a system as stable as the climate.

    The Negative and Positive feedbacks are caused by vastly different things, yet it is blithely assumed that they can be offset against each other, because the analysis done in climate is a scalar one.

    Since the lags are different the impulse responses will be vastly dissimilar, and you cannot just combine dissimilar loop gains gains like this. The temporal aspects need to be quantified. I contend that this requires Complex number math to solve. Scalar Climate models could therefore not possibly predict response of this system at all. There seems to me to be a huge gaping hole here…

    I have a lot of trouble accepting the assumed feedback can be factual, it seems to defy Physics?

    Comments anyone?

    [Response:You are misunderstanding the definition of feedback in this context. Climate feedback is defined as a multiple of the basic damped response due to the Planck feedback. An effect leading to a larger net response than that is defined as positive feedback, an effect leading to a smaller once than that is termed a negative feedback. But the overall feedback in the sense you are assuming is dominated by the Planck (longwave response). - gavin]

  42. 42

    “Scalar Climate models could therefore not possibly predict response of this system at all.”

    It sounds as though you could do a bit of reading on how climate models actually work. Sensitivity is emergent, not prescribed, for GCMs.

  43. 43
    deconvoluter says:

    Re: #41

    If you want it answered it would be better to set out the argument clearly , i.e. put away the handwaving and write out the algebra from first principles without reference to anything else. You will need to show why this gain of 15 is not a fictitious straw man.

  44. 44
    Hank Roberts says:

    > You are misunderstanding the definition of feedback in this context…. – gavin

    That’s the key for Bobi. Over and over, an engineer (or someone prompted by an engineer) comes here to explain that everything climate scientists know is wrong because they don’t understand feedback.

    Wrong. It has various definitions.

    Start by learning what the word means in the field being discussed.

    AIP:Discovery of Glob. Warm.Spencer Weart’s ‘Discovery of Global Warming’ book (first link under Science in sidebar) is basic — learn how this stuff got figured out. Hint, it took big computers and an understanding of much about the atmosphere.

    Also helpful: the links behind the Start Here button, top left corner of page.

    Engineers, take note — if you don’t understand the different meanings of the word “feedback”, odds are that you’re using the word wrong in this context.

  45. 45
    Hank Roberts says:

    “… strategies to rely on sequestration of CO2 as a mitigation strategy must recognize the high freshwater costs involved, implying that the key climate mitigation strategy must be to reduce emissions.”

    GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L15401, 8 PP., 2012

    doi:10.1029/2012GL051688

    The planetary water drama: Dual task of feeding humanity and curbing climate change

  46. 46
    Dan H. says:

    Bobl,
    In climate models, as opposed to other sciences, feedbacks are presumed to operate differently. Hence, rather large multiplier are possible, which would appear to defy physics. When you approach this from a purely mathematical direction, if seems impossible, as you state. However, when using the Planck feedback, it is entirely possible. You need to understand the concept of feedback defined by climate modelers.

  47. 47
    Susan Anderson says:

    Justin Daniel @~35

    Tamino went right into it. Coauthors are skittishly dancing away. It’s about, among doubtless other obvious flaws, the TOB (time of observation) and if I understood correctly, some issues with rural sitings which are less consistent and in some cases have been moved which must be factored in. One Victor Venema provides real, not fake, knowledge on the subject(see comments as well in link). It’s always easy to carp from the sidelines, cosmetic but not truthful:
    http://tamino.wordpress.com/2012/08/01/much-ado-about-nothing/
    http://tamino.wordpress.com/2012/08/01/much-ado-about-nothing/#comment-64952

  48. 48
    SecularAnimist says:

    I’ll leave the solar naysayers to willfully ignore the realities of today’s rapidly growing solar energy industry, and to their ill-informed assumptions and guesswork and back-of-the-envelope calculations. Thousands of consumers and utilities all over the USA are proving them wrong every day.

    I’ve got in front of me a proposal from a local solar installer for a 3.4 KW roof-mounted, grid-tied array of eighteen 190 Watt Suntech modules, with Enphase micro-inverters, that would cost about $12,500 after available tax credits, provide 27 percent of my current annual electricity consumption, saving me $489 per year on my electric bill plus $1,014 from the state’s tradeable Renewable Energy Credit program, for an annual savings of about $1,500, which is a 12 percent return on investment, and about an 8 year payback period (less if the price of grid electricity increases). The panels are warrantied for 25 years, so after the 8 year payback period I’ve got another 15 or more years of free electricity.

    Sounds good to me. And there would still be room on my roof for another 6 KW of those Suntech panels, or cheaper-and-better ones when available.

  49. 49
    Tom Adams says:

    The US state of North Carolina just banned the use of projections of sea level from planning for 4 years:

    http://hamptonroads.com/2012/08/southern-states-fight-estimates-sea-level-rise

    This is a watered down version of the earlier bill (with no time limit) that banned the use of projections that took future global warming projections into account.

  50. 50
    David Levitt says:

    In Muller’s recent interviews (see, e.g. http://www.rawstory.com/rs/2012/07/30/richard-muller-get-rid-of-coal-power-to-halt-global-warming) he states that “Natural gas produces one third the carbon dioxide of coal for the same energy”. Is this right? The figure I have usually seen is two thirds.brandt


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