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Unforced variations: Sep 2012

Filed under: — group @ 5 September 2012

Open thread – a little late because of the holiday. But everyone can get back to work now!

591 Responses to “Unforced variations: Sep 2012”

  1. 151
    Jim Larsen says:

    273 Chris D said on the arctic ice thread, “Suppose, for example, that CAFE standards have limited consumption”

    1. CAFE standards are broken. electrical vehicles are given a 2/3rds benefit for no reason at all. This means that CAFE increases just force emissions from oil to coal and methane. NO carbon reduction at all. It’s all about externalizing.

    2. My post was about the world, not the USA. Yep, drop US consumption of oil and oil prices will drop, but that will increase oil consumption, as oil production is based on essentially free production VS any old price. So, drop the price and producers scramble to INCREASE production to make up for the shortfall. Seriously, what will Saudi do if their GNP drops by ~60%? Drill, baby, drill.

    The potential market for oil at $25 a barrel is HUGE. Drop oil prices through conservation, and you just increase the market. All those 3rd worlders suddenly can afford to ditch the bicycle… (Damn them! So uppity…)

  2. 152
    Didactylos says:

    Jim Larsen, are you making the “long tailpipe” argument? You should know that’s flawed, even without making the further point that coal and gas also need replacing with renewables.

  3. 153
    Rob Dekker says:

    To change the subject from Arctic to Antarctic for a second,

    Many of you will remember the ‘skeptic’ blogosphere Steig-bashing frenzy after O’Donnell et al 2010 was published.

    New bolehole data is available from Orsi et al 2012, which again confirms Steig’s reconstructed trend at the WAIS divide.

    Over at WUWT, I am trying to get a scientific answer on what Orsi et al means for the results of the O’Donnell et al paper.

    Now, you need to kind of wrestle your way through the ad hominems and Steig-bashing (starting with the title), or you can start here where it gets very interesting :

    after which Nic Lewis eventually states this :

    The OLMC reconstruction 1957-2006 trend at Orsi’s borehole location is 0.13 C/decade below the mean of Steig’s and Orsi’s trends. Increasing the OLMC trend of the (infilled) Byrd station record by 0.13 C/decade to reflect that difference would leave the overall OLMC 1957-2006 continental trend below 0.07 C/decade – still insignificant.

    In other words, if the O’Donnell et al reconstructed trend at the WAIS divide would be adjusted to the Orsi et al borehole data, the overall trend result from O’Donnell et al for the entire continent would become +0.07 C/decade +/- 0.08 C/decade.

    Which reduces the claims that O’Donnell shows that “whole of the continent is not warming” to a rasor-thing margin.
    That’s quite interesting, no ?

    Now I have TWO co-authors (Nic Lewis and Jeff Condon) giving arguments that are over my head :
    “…PCA creates false resonances in the spatial temperature information. These show up as Chadni patterns…” and I am
    “confusing Steig’s reconstruction trend for the grid cell containing Byrd with Steig’s actual trend for the infilled Byrd station record”, and “Steig’s 1957-2006 trend for the infilled Byrd station record was only 0.135 C/decade, NOT 0.23 C/decade”.

    What does that all mean, and are these comments relevant to O’Donnell at al’s trend reconstruction in the face of new temperature data (such as the Orsi et al borehole data) ?

  4. 154
    Superman1 says:

    Didactylos #148,

    This may be a repeat; CAPTCHA is causing me problems.

    “I would expect to see unfounded optimism on certain websites out there, but hearing it from someone who has been reading RealClimate for some years is quite astounding.”

    Let me place your comment in its larger context. There is a belief on blogs such as this that if only the electorate were to get the Truth about climate change, there would be major actions taken to dodge the bullet. Further, the blame for no action on climate change is usually placed upon the ‘deniers’, the fossil fuel companies that they faithfully serve, and the politicians that are bought and owned by these companies. My ‘take’ is that this is all a game. The electorate knows reasonably well that harm is being done to the climate. The central problem is that this knowledge is insufficient to spur the electorate into serious action.

    Basically, the electorate is addicted to a lifestyle that requires the intensive energy use that only fossil fuel can provide today. Like any addict, they are willing to do whatever it takes to satisfy their addiction, even if it means sacrificing the survivability of their progeny. The deniers are what Lenin used to call ‘useful idiots’. I don’t believe anyone takes them seriously, or even listens to them. The energy addicts may point to the deniers’ ravings to help justify their continued addiction. But, it’s convenient to point to the deniers, or the fossil fuel companies or the politicians for the source of inaction, rather than to the real problem, ourselves.

    I personally cannot understand what makes the deniers tick, or why they would spend time on a Web site such as this spouting what is obvious nonsense. But, they are the ‘shell’, and if we are to get out of this stalemate, we need to concentrate on the ‘pea’.

    Are their similar precedents in history? Take smoking, for example. In the early 50s, when I was at the smoking initiation age, it was well known that people who had been smoking for a few years had numerous sore throats, and some developed ‘smoker’s cough’. It was also well known that people who had smoked for a number of years could have emphysema or circulatory problems such as Burger’s Disease. and, we all knew people in their 40s and 50s who had developed lung cancer. Nevertheless, I don’t believe any of us were dissuaded from smoking because of the knowledge of potential adverse consequences. It was the macho thing to do, and there was strong peer pressure to do it. Advertisements bolstered the positive images.

    Smoking had its myriad deniers, bought and paid for by the tobacco companies. But, smokers would only reference them to help justify continuance of their habit; nobody believed their nonsense.

    In 1964, the Surgeon General’s Report on smoking was issued, documenting its myriad problems. The evidence was probably ‘harder’ than that for some of the climate change predictions today. What impact did this relatively ‘hard’ information have on the smoking community?

    According to an interview I heard a couple of years ago with the NYT reporter who covers the tobacco industry, the answer was essentially none. 42% of the adults in 1964 smoked, and essentially none discontinued as a result of the report. What dropped the smoking rate to the 21% level today was economic penalties such as higher taxes and prices, mandates such as smoking exclusion zones, and some advertisement effect.

    Now, one might argue that the 1964 Report enabled the economic penalties and the mandates. I would argue that it helped, but the real reason the penalties and mandates were enacted was that 60% of the adult population did not smoke, and many, like myself, were offended by the smell. It was the will of the majority that smoking should be penalized and confined, and the Report was the tool that was used to justify the ‘will’.

    In the intensive energy use case, the numbers are amplified and reversed. Rather than 42% addicts as in the smoking case, we probably have 95% or more addicts in the intensive energy use case. That’s why no action will be taken, no economic mandates or penalties will be issued, and no political initiatives will be taken. Unlike smoking, the energy addicts are the super-majority, and they will determine what actions the politicians take and what is done to the fossil fuel companies.

    So, while your quote above is certainly valid, it’s being wasted on a nonsensical comment. We are the problem, and until we can be persuaded to alter our energy addiction radically, the problem will not be solved. As my other posts have shown, I believe we have gone past the point of no return already, but even if we haven’t, I see no initiatives to stop the train from going over the cliff.

  5. 155
    Hank Roberts says:

    >> climate models today don’t incorporate many,
    >> if not most, of the positive feedback effects.

    Citation would be helpful.
    Got a list of what’s identified and weighed but not in the models?

  6. 156
    Steve Fish says:

    Here is some kryptonite for Superman 1’s argument. Read “The Carbon Buster’s Home Energy Handbook,” by Godo Stoyke, where one can learn how to save money while reducing atmospheric carbon. The charts of such things as embodied energy and maintenance energy are fascinating, and the savings can be considerable.

    The actual cost of a pair of polyester pants and a superhero costume is pretty high. Steve

  7. 157
    Patrick 027 says:

    Re 151 Jim Larsen –

    Jevon’s paradox?

    An element of truth, of course. At least for the more familiar supply-demand slopes, If someone reduces their consumption, prices tend to fall, so others will tend to consume more.

    But if others consumed exactly as much to keep the total consumption the same, prices would tend to remain the same (or at least on the same trajectory). The price has to stay lower in order to sustain the increase in consumption, so the increase in consumption must be limited somehow. That depends on the slopes of supply and demand. Add in the effect of some country also voluntarily reducing their production – the price would have to rise to keep global production the same.

    PS yes, EV’s mpgs are weird.

  8. 158
    Hank Roberts says:

    for ‘Solutions’ (not saying this is the best price on the thing or that I know anything about it, except I’ve read these things exist — people who monitor their electricty use realtime reportedly use less)

  9. 159
    Hank Roberts says:

    > solutions
    Or there’s the much less expensive tool that’s been around a while: Kill A Watt™, for example

  10. 160

    “Nature always seems to exxaggerate these changes, prior to a pull back, and similar to five years ago, I would expect that the sea ice minimum will be higher next year.”

    Expect away, Dan. You may be right, but forgive me if my expectations differ–I expect we’re in really new territory here, and what we have seen in the past may not be much of a guide to what comes next.

    Some reasons I think so can be gleaned from an article I just published:

    (And, FWIW, statements beginning with “Nature always seems…” always seem to make me, er, skeptical.)

  11. 161
    Chris Dudley says:

    The description of a new National Academies book on Himalayan glaciers starts: “Scientific evidence shows that most glaciers in South Asia’s Hindu Kush Himalayan region are retreating,”

    Andy Revkin translated this as “The bottom line — in sync with other recent analysis — is that the region is seeing a mix of changes, with glaciers growing in some places and shrinking in others and impacts on water supplies mostly inconsequential for decades to come.”

    Must be an election year.

  12. 162
    Patrick 027 says:

    Re 130 Ron R. – a solution not for AGW in the near term, but maybe in some future situation(?): Giant space mirror/shade. Alternative – a lot of little ones (remote controlled steering with gyroscopes and solar-powered…?) . Key point: preferentially block the solar IR – specifically/especially the parts that tend to get absorbed by water vapor in the troposphere – therefore a cooling effect without the same reduction in global precipitation that one would get with aerosols (also may be important in considering photosynthesis and solar energy, depending on just how much cooling we’re trying to accomplish – although if the problem is the brightenning sun (~100s of millions of years from now?), simply blocking the whole spectrum may be just fine).

    If we were going to emit aerosols I’d suggest something like crushed dunite. If it falls out to quickly at least it may take some CO2 with it – it would be interesting to compare the size of the two effects.

  13. 163
    Jim Larsen says:

    152 Didact asks, “are you making the “long tailpipe” argument?”

    Heavens no. I’m saying that fossil fuels are way cheap except externalities. Thus, every barrel, every ton of coal, every cubic foot of methane WILL sell to somebody at some price. Yep, current electric cars produce more CO2 than fossil fuel cars, and that will remain the case for as long as current cars are still on the road, so every electric vehicle sold today makes global warming worse, but that’s minor. More important is that fossil fuel producers have no choice but to sell at any price. $100 a barrel? $50 a barrel? $25 a barrel? Still the same decision for the producer – drill, baby, drill before somebody stops the party by taxing fossil fuels out of the market and enforces the decision by embargoing nations that continue to consume. Coal is the current example. We as a nation chose to drop our coal consumption. This had little effect on coal production. We can drop our oil consumption as well, and similarly it will have little effect on oil production. Seriously, can you imagine a scenario where Saudi Arabia decides pumping oil for $2 and selling it for $25 isn’t worth the effort? Can you imagine a scenario where $25/barrel oil isn’t snatched up by somebody? Can you imagine renewables dropping to the actual cost of production for fossil fuels ($2-20/barrel)? If not, then obviously pricing or national policies can’t change oil/coal/gas production enough to matter, and there will ALWAYS be a willing buyer at a price above the cost of production. Drop the price, and producers MUST increase production. If the US burns coal and methane instead of oil, it just frees up somebody else to snatch up even more oil at a lower price.

    The math is clear. 350 million = 25%. 7,000 million can slurp up 100% easily even if billions abstain.

    The marketplace simply can’t drop fossil fuel production, and since we don’t have a one world government, there will always be willing consumers. All we can do by electrifying our cars is make gasoline cheaper for other folks, which means more gas will be consumed. (If the consumer is poorer, then producers will drop prices to match the ability to pay, and increase production to maintain profits.)

    We tend to focus on the inelasticity of demand, but the REAL issue is inelasticity of supply. Drop consumption by 10% and prices will plummet. Producers simply can’t drop their production – even a cartel like OPEC has to struggle to drop production a couple percent. Once drilled, a well is essentially free money. Who’s gonna shut off their free-money machine?

  14. 164
    John Mashey says:

    re: 159 Kill-a-Watt, etc
    These things are so hard to use :-)
    A 12-year-old girl next door and her friend did a 2-week project where they checked their houses, found different profiles, vampires, etc, wrote up a nice project for school.

    I think they knocked off 20% of the usage just by having measured.
    Everybody I know who has ever done this has been surprised and gotten easy savings.

    Jevons is highly over-interpreted.
    The number of miles someone drives is not directly proportional to the gas price, that is, there is an elasticity curve and it is not linear. Nobody would spend every minute in their car just because gas price went to zero.

    Some electric utilities used tiered pricing, and if someone does efficiency improvements that lower their tier, they don’t turn around and try to use more to get back into a more expensive tier.

  15. 165
    Jim Larsen says:

    “Jevon’s paradox?”

    Not exactly. Fossil fuel producers are surely aware that they are a doomed species. 100 years from now nobody is going to be buying fossil fuels. Thus, producers have a great incentive to sell as much as possible as soon as possible. Since fossil fuels are like software – essentially no cost per unit sold – price is irrelevant to production. This totally destroys the stereotypical demand/production curves.

    The result is that price simply doesn’t matter. It’s a game. Charge as much as you can while pretending you could withhold production if prices were lower, but regardless of market forces, you WILL produce as much as humanly possible, and lower prices actually provide incentive for increased production. It’s amazing that the oil companies have been able to collude enough to prevent over-capacity. Seriously, can you imagine a FREE marketplace where a product sells for 1000% of its cost and yet production doesn’t increase beyond demand?

  16. 166
    Dan Riseborough says:

    If I may, I would like to ask a very open-thready question, otherwise completely off topic.
    It’s a basic question about atmospheric CO2. I occasionally talk to undergraduates about soil carbon storage, and relative global quantities in the air and ground comes up. To give perspective, I’ve estimated that if all the CO2 in the atmosphere was reduced to a layer of dry ice at the ground surface, it would be about 4 mm thick. Can anyone with a more knowledge confirm/refute this?

  17. 167
    wili says:

    “can you imagine a FREE marketplace where a product sells for 1000% of its cost and yet production doesn’t increase beyond demand?” hmmmm…cigarettes?

    Keep in mind that it’s not just the private companies, bad as they are. A lot of the top oil producers have state-owned companies like ARAMCO. And of course these same countries have formed OPEC specifically to control prices.

    As to your other argument, it seems to boil down to “if I don’t do it, somebody else will”–not generally considered the highest level of moral justification for despicable behavior (burning up our children’s future).

    (reCaptcha: come one do wel)

  18. 168

    Science works by refutation of the hypothesis. The contrarians’ hypothesis is that our CO2 will not cause serious problems because Climate Sensitivity (CS) is low. They are coy about putting a number to it, but some go for 0 – 0.5*C.

    This figure, and any figure below 1.5*C is refutable, is it not?

    Would it not help (to some extend at least) for the climate science community to issue a monograph that decisively refutes the contrarian hypothesis? Although nothing will stop the core ideologues, there are many genuinely confused journalists and politicians who are influenced by the obbligato of doubt played by the fossil fuel lobby.

    They may not fully understand the science, but they can understand “disproven”, and a wider perception of the fact that the contrarians have no elastic in their low CS knickers may help us all to move on with the business of decarbonising the world economy.

    Worth a shot?

  19. 169
    MARodger says:

    Dan Riseborough @165
    4mm sounds a bit on the low side to me!
    CO2=c400ppm at 2.13GtC/ppm = 850GtC = 3,200GtCO2.
    Dry ice sg = c1.5 so your layer has volume = 2,400e9 m^3 & area 510e12 m^2.
    Thus thickness = 2.4/510 = 0.0047 m = 4.7 mm.
    But then I may have placed a decimal point upside down here, or forgotten to divide by the number I first thought of. Arithmetic never was a strong point of mine.

  20. 170
    Steve Fish says:

    Re- Comment by Jim Larsen — 12 Sep 2012 @ 11:55 PM and — 13 Sep 2012 @ 2:12 AM:

    Take a deep breath, have some milk and cookies, and take a nap. Then, start referencing your statements. E.g. – “current electric cars produce more CO2 than fossil fuel cars;” – 25$ or 2$/barrel petroleum production cost; -“Drop the price, and producers MUST increase production.”


  21. 171
    Steve Fish says:

    Re- Comment by Dan Riseborough — 13 Sep 2012 @ 8:10 AM:

    A good teaching gambit when talking about how a small amount of CO2 can have a big influence on temperature is to compare this to the effect of a 1 mil (250 micron) plastic sheet covering the earth that was either silvered or flat black. Like tetrodotoxin, a small amount can be dangerous. Steve

  22. 172
    Hank Roberts says:

    Patrick 027 says:
    > orbiting … Key point: preferentially block the solar IR

    What? What’s the point of blocking the solar IR?

    The infrared from the atmosphere is most of our problem.

    A citation every now and then to support ideas would be helpful

  23. 173
    Ray Ladbury says:

    Jim Larsen:”…essentially no cost per unit sold – price is irrelevant to production.”

    Say what? Uh, Dude, if this were true, would it make sense to drill in deep water? …in the Arctic? And then there are refining costs. Methinks somebody needs to review supply and demand.

  24. 174
    Dan Riseborough says:

    MARoger @169: Thanks – I consider getting within 20% pretty good at this point. I based my calculation on a unit area at the surface, which underestimates the volume of the column. I was most concerned about getting the order of magnitude right.

  25. 175
    Ron R. says:

    Patrick 027 at 11:37 PM.

    It may be that we might not even need to block out that much sun. Consider that the hottest point on the planet at any given time of the year is the point directly facing it. Areas with glancing rays are a lot cooler, with cooling increasing in proportion to angle. Thus summer and winter. If we simply focused on the focal point, keep the filter in a solar (not geo obviously) orbit, say mid way (not clear on that) between the earth and the moon such that that point is, wherever it is on the earth at any given time of the year, shaded that may be enough to offset increased warming due to CO2.

    Perhaps easier said then done.

  26. 176
    simon abingdon says:

    #169 MARoger #165 #174 Dan Riseborough

    Or, slightly more accurately,

    CO2=c391ppm at 2.13GtC/ppm = 833GtC = 3,054GtCO2.
    Dry ice sg = c1.56 so your layer has volume = 2,308e9 m^3 & area 510e12 m^2.
    Thus thickness = 2.308/510 = 0.0045 m = (perhaps only about) 4.5 mm.

  27. 177
    dbostrom says:

    Ron R. re extraterrestrial solar shading: Perhaps easier said then done.

    A solidly qualified candidate for understatement of the year!

  28. 178
    Steve Fish says:

    Re- my comment — 13 Sep 2012 @ 10:00 AM:

    Oops, I screwed up my decimal. 1 mil would be 25 microns. 25.4 to be exact. Steve

  29. 179
    Hank Roberts says:

    > sun. Consider that the hottest point on the planet at any given time
    > of the year is the point directly facing it

    Using your own logic?

    Try citing an actual measurement; this may help:

  30. 180
    MARodger says:

    simon abingdon @176
    Goodness. You appear to be demonstrating arithmetical skills almost as dire as mine. The operative phrase you use is certainly “slightly more accurately.
    The most significant of the errors I managed @169 was in converting weight to volume. Dry Ice sg is actually rather variable (I see 1.4 – 1.6 quoted on Wikipedia & down as low as 1.2 elsewhere). But my attempt to divide by a quoted 1.5 turned into dividing by 1.333. So all in all, at 1.5sg it appears Dan Riseborough’s 20% error pretty much shrinks, not to your 12.5%, but to a massive zero. Hurrah.

    For the record as graphed here, average annual CO2 is now above 393ppm.

  31. 181
    Hank Roberts says:

    > filter in a solar (not geo obviously) orbit, say mid
    > way (not clear on that) between the earth and the moon

    You’re thinking of L1:

  32. 182
    Ron R. says:

    Hank, what that page talks about is records. Sure there are individual places that are hotter than others. However you will notice that those record breaking locations are latitudinally all very similar. That’s because that’s where the sun hits the earth most directly. Place a screen on that trajectory between the earth and sun.

    I know you know this but here’s quote:

    The same also holds for the Earth. The rays of the summer sun, high in the sky, arrive at a steep angle and heat the land much more than those of the winter sun, which hit at a shallow angle. Although the length of the day is an important factor in explaining why summers are hot and winter cold, the angle of sunlight is probably more important. In the arctic summer, even though the sun shines 24 hours a day, it produces only moderate warmth, because it skims around the horizon and its light arrives at a low angle.

  33. 183
    Ron R. says:

    Hank Roberts at 3:10 PM: You’re thinking of L1:

    Ah, thanks. Hadn’t seen this comment before. That looks about right. I note though this:

    Side-effects include that, if this lens were built and global warming were avoided, there would be less incentive to reduce greenhouse gases, and humans might continue to produce too much carbon dioxide until it caused some other environmental catastrophe, such as a chemical change in ocean water that could be disastrous to ocean life.[12]

    Anyway, that’s one solution. Maybe we should start lighting candles rather than just cursing the darkness.

  34. 184
    Ron R. says:

    Sorry. Looking at that wiki page I think I got distracted and forgot my point. The picture of the L1, yes, but that shows it shielding the entire planet. I’m not sure that would be necessary. Again, maybe just shielding a portion of it, at the latitude where it hits the most directly would be enough. Much more doable at least.

    The idea of using mirrors or blocking it out entirely at a certain point though would not be advisable of course for a variety of reasons. But filtering it, allowing a diminished percentage of rays through which, taking into account the fact that more is bouncing around within the atmosphere due to the greenhouse effect, one could adjust the light to reflect normalcy I would think.

  35. 185
    David B. Benson says:

    Summer Rain More Likely Over Drier Soils, New Satellite Data Show
    which comes as a surprise?

  36. 186
    Superman1 says:

    I’m trying to estimate how far down are we in the climate hole we have dug, and is it possible to dig our way out. If we use pre-industrial temperature as the base, we are about 0.8 C above that today. Already, we are seeing a sharp increase in extreme events, as Hansen’s recent paper has shown, we are probably seeing the disappearance of at least the Summer Arctic sea ice, and we are seeing substantive increases in Arctic methane emissions from the permafrost, wetlands, and water column. What is the evidence that precludes our being at the initial stages of a runaway positive feedback loop even at this level of temperature increase?

    Irrespective of future CO2 emissions, we have a ‘climate commitment’ of temperature increase from CO2 already placed in the atmosphere of about 0.7 C, due to lags in the system. That brings us to a temperature increase in a few decades of about 1.5 C. What is the evidence that precludes our being at some stage of a runaway positive feedback loop at this more substantive level of temperature increase?

    Now, in the limiting case that we terminate CO2 emissions tomorrow, the fossil sulphate aerosols that were placed in the atmosphere from fossil fuel combustion will be naturally flushed in a relatively short time. These aerosols had a cooling effect on the Earth by effectively increasing its albedo, and the cooling effect will now be gone. The full heating due to the CO2 forcing will now be displayed. Different papers give different values for this aerosol increase, due to different assumptions on climate sensitivity and aerosol forcing, but recent papers estimate it could be as much as 1.0 C, or even higher. So, in a few decades, the total of the above temperature increases would be on the order of 2.5 C, with the possibility of being perhaps slightly higher.

    Now, these estimates are for what we have done to the climate so far. They do not include future CO2 increases, nor do they include the major positive feedbacks. Is there any evidence that we can avoid a runaway positive feedback loop at the 2.5 C temperature increase, seeing the feedbacks that have already come into play? In other words, is the game over based on what we have done to this point in time, never mind the additional damage we will do with continued fossil fuel combustion?

  37. 187
    Neil says:

    RC community,

    Below is a segment from an email I recently received regarding statements made by a scientist at APL. I am not an expert at remote sensing, so would greatly appreciate your responses to the statements made below. Many thanks in advance.

    “As far as I know, there is no reliable measure of average Earth temperature from space. There are many long-term Earth based measurements of temperature and CO2 from a variety of places that are used to try to reconstruct the “average” surface temperature.

    The solar input is measured from space and there are about 30 years of high quality measurements by a half dozen or more spacecraft. However, the intercalibration among the separate satellites is not as good as needed. Each spacecraft has measurements of relative changes that are very good. They are looking at changes of 0.1% or less and the baseline offset from one spacecraft to another is larger than that. The lifetime of a single spacecraft is 3 to 10 years. So when they try to assemble a long-term trend they have to make their best estimate of the baseline offsets and some significant uncertainty remains. The NASA planned CLARREO mission is being designed to have the best absolute calibration of any mission so far. But it is still a few years off and it will then take a decade or more to start to get a measure of absolute solar input changes.”

  38. 188
    Unsettled Scientist says:

    >The picture of the L1, yes, but that shows it shielding the entire planet. I’m not sure that would be necessary.

    It shows a diffraction, not a shadow. It is not blocking the sunlight, it is dispersing it. You wouldn’t want to go the other way and concentrate the light.

  39. 189
    Patrick 027 says:

    Re Hank Roberts – 172 – see “Global Physical Climatology” by Dennis L. Hartmann, for example.

    A majority of solar (mainly SW) heating occurs at (or somewhat under, as in the ocean) the surface, but a significant amount does occur in the atmosphere – some UV heating in the stratosphere, of course, and a larger amount in the troposphere, where SW radiation (but not visible – it’s IR but not LW (not terrestrial) is absorbed by water vapor, and some by clouds, and other gases. If this were absorbed at the surface instead, it wouldn’t have any effect on tropopause-level forcing (setting aside the increase in albedo by allowing more radiation the opportunity to be scattered/reflected), but it would increase the net radiant heating of the surface and thus increase convective cooling. On the other hand, if this radiation were blocked from reaching the Earth entirely, it would contribute (negatively) to tropopause-level forcing without affecting convection (specifically refering to that portion which is absorbed – of course atmospheric absorption depends on the sun’s angle (thus on latitude and time of year as well as day) and atmospheric H2O and clouds (and surface elevation), etc, so in practice it may be hard to have a cooling effect without reducing solar heating of the surface at all.

    (PS if you are going to selectively block wavelengths of radiation from reaching the Earth, be careful in the UV, because – my understanding is – shorter wavelength UV is necessary to produce ozone, which then absorbs longer wavelength UV.)

  40. 190
    Unsettled Scientist says:

    > “As far as I know, there is no reliable measure of average Earth temperature from space.”

    Take it a step further even, there is no measure of Earth temperatures from space, at all. There is no such thing as a satellite thermometer, only a satellite model (as Stephen Schneider once put it).

  41. 191
    Patrick 027 says:

    re 143 Russell –

    I did a quick read-through; I may have skipped a few parts.

    1. a heads up – I only openned it up in a new tab, and I closed some sort of popup that appeared in front of it. When I minimized the windows that I myself openned, I found one that had appeared on it’s own, that said something like ‘Whoa, are you sure you want to go there’ – from my antivirus/security software.

    So make sure you’ve got something like a ‘Site Advisor’ running when you go to that (Russell’s provided link).

    2. I won’t go back and I’m probably not the best person to comment on it anyway, but …
    … I didn’t get how everything was derived or what exactly all the charts were about (it was a quick look that I took), but one thing that occured to me-

    if they averaged the PDSI for the whole country, or even just the 48 contiguous states (plus DC?), this would smush some floods into some droughts.

  42. 192
    Patrick 027 says:

    I found one that had appeared on it’s own, that said something like ‘Whoa, are you sure you want to go there’ – from my antivirus/security software.

    To be clear, there was the option of contuing to whatever that window was supposed to be. So the window itself was not openned by my security software – that just (I believe) prevented the window from going automatically to whatever it was supposed to be.

  43. 193
    Rob Dekker says:

    Ron R,
    A solar shield at L1 would not block the entire face of the sun, just enough to compensate for CO2 TOA forcing.

    Rather than a “solution” to reduce GHG induced global warming, it is more interesting to see what the cost would be per ton CO2 emitted.

    That puts a price on CO2, and thus we could balance that cost against alternatives.

    So here is my back-of-the-envelope calculation on how much it would cost to put a space mirror in place that compensated for forcing caused by one ton CO2 :

    To get an idea of how large the mirror would need to compensate for one ton CO2 emitted, we can calculate the ‘forcing’ that ton causes (since a doubling of CO2 in the atmosphere from 280->560 ppmv causes about 3.7 W/m^2 forcing).

    If you do the calculations with that it turns out that every ton of CO2 that we add to the atmosphere creates about 1 kW extra forcing (heating) for the planet and thus we need a space mirror of about 1 m^2.

    Next, the study below suggests that we could make autonomous operating space mirrors of micron-thin material which have a mass of only 4 gram/m^2. Current launch costs to bring a payload into high orbit (L1) is about $20,000 per kg. So the launch costs alone for a 4 gram 1 m^2 mirror which compensated for 1 ton CO2 is about $80.

    $80/ton CO2 is some $300/ton Carbon. And that’s just the launch cost.

    I’m sure that we can do much better things if we were only to recognized the real cost of repairing (some of) the disturbances that our carbon emissions cause.

    Either way, here is a NASA-supported study that investigates a hypothetical system that could possibly block enough sunlight to compensate for our current emission rate :

    Which proposes an 2km long electromagnetic canon mounted on a 5km mountain top, which fires a 1 ton payload (of about a million highly autonomous operating mirrors) into the L1 point.

    It needs fire every 5 minutes, non-stop, 24/7, just to compensate for our current emission rate.

    Great read.

  44. 194
    Ron R. says:

    Rob Dekker thanks for the link. Interesting. It may be a great idea but just reading your comments and the abstract, and playing devil’s advocate here, a few comments.

    1. I have doubts that “micron-thin material which have a mass of only 4 gram/m^2” would make it into space without major distortion or destruction.

    2. Shooting these mirrors from a giant cannon doesn’t sound terribly precise.

    3. Has their been an estimation about how many of these little mirrors would fail to make it into space and would fall back to earth? I’d guess it would be a lot of them. About how long these light weights would hover in the atmosphere with possible damage to airplanes, disruption to satellite signals etc? About the harm to animals such as sea fauna that might ingest them?

    4. What happens at reentry time (perhaps they’d burn up)?

    5. A discharge (which I assume would be mighty loud) every 5 minutes, non-stop, 24/7, just to compensate for our current emission rate? Wow.

    6. Honestly this sounds like it would be another undoable geoengineering “solution” which more closely resembles littering to me. And lastly,

    7. I’m not sure the $3,000,000,000,000 price tag for a mere 50 years is going to sit well with most people.

  45. 195
    Jim Larsen says:

    Ray and Steve,

    Steve, I used the Toyota Prius and Nissan Leaf as representative of state of the art for electrical VS gas vehicles. The Prius gets 50MPG and the Leaf gets 99/3= 33MPGe (Gotta divide by 3 to account for power plant inefficiency and transmission losses. I assumed that our mix of coal, n-word, CH4, and renewables is about as carbon intensive as oil. I welcome data if someone wants to do the figures.) Adjust the Leaf upwards since over its 15 year life renewables and CH4 will reduce the carbon intensity of the grid, but the Prius will still win the carbon game. (Unless Secular A is elected World President – then the Leaf wins!)

    The primary costs for oil and gas are from finding the field, drilling the wells, and building the infrastructure needed to get the product to market. Wells, super tankers and pipelines are heavy on capitalization cost and light on operating costs. I’m pretty sure refineries are similar. Once built, the entire supply chain has an incredibly high gross margin, and also has little residual value besides scrap (you can’t move a well, and what are you going to do with a super tanker besides ship fossil fuel?). My post is limited to the time period after the well is producing, and it totally ignores sunk costs, as business decisions also ignore sunk cost. Coal is different, so this analysis doesn’t apply to coal.

    Look at fig 3, which shows current fields’ production through 2035. That is our baseline, as it represents oil which has already been paid for. It is free energy, or at least pre-paid.

    The USA is attempting to slowly drop consumption while massively increasing production. Most every country with the ability is following the same policy. That effort simply frees up the current fields’ production for others to consume. Since the costs are paid up front, current field owners have an easy decision. Pump. Pump. Pump regardless of price – perhaps even at a net loss as long as operating costs are covered. This means the world is taking the next level shown in the figure, discovered fields which haven’t been developed yet, which is a serious danger, as it means CO2 emissions won’t decrease very much.

    We are at the decision point right now. The existing field production curve matches a reasonable worldwide carbon plan. Thus, drilling new wells is folly, as once drilled, their costs are pre-paid, and so they become free money machines as well.

    So every well drilled, every pipeline built, every tanker constructed from now on is pure-t-insanity. We already have all the fossil fuel production capacity that our planet can handle. We can stop fossil fuel development now, we can take Hank’s suggestion later (pay producers to not produce – won’t it be a hoot if we replace Saudi with expensive deep water wells and then have to pay Saudi anyway!), or we can bake the planet. So take your pick: cheap, incredibly expensive, or fatal.

  46. 196
    Hank Roberts says:

    ocean pH change is happening faster than atmospheric CO2 is increasing; a sunshade would make it worse, unless the sunshade is made out of frozen CO2 extracted from our atmosphere.

  47. 197
    Patrick 027 says:

    John M. Wallace, Peter V. Hobbs, “Atmospheric Science – An Introductory Survey”. Academic Press, New York, Toronto, 1977. [when, of the two closest cities, one is in the same country but the closest is not, which is the proper one to give?]

    Dennis L. Hartmann, “Global Physical Climatology”. Academic Press, New York, Toronto, 1994.

    Hartmann, p.28:
    Location absorbed: % of TOA insolation ( 342 W/m2) absorbed
    Stratosphere: 3
    Troposphere: 17
    Surface: 50

    Hartmann, p.27:
    The stratospheric 3 % : mostly O3 and O2; ~ 0.5 % from CO2 and H2O vapor.
    The tropospheric 17 % : 13 % from H2O vapor, 3 % from clouds, 1 % from CO2, O3, and oxygen together.

    Hartmann p. 31 fig. 2.6, 2.7, and text p.30 –
    highest daily average insolation at TOA is approximately found at (or near?* – I could go through the calculation to verify but I won’t right now…) summer solstice poles (some deviation will be found due to eccentricity of orbit).

    Hartmann p. 49: O2 is dissociated by wavelengths shorter than about 200 nm; O3 is dissociated by radiation between 200 and 300 nm [I’d guess it could be dissociated by shorter wavelengths too, but those are perhaps blocked by O2].

    Wallace and Hobbs pp.328-:

    wavelengths shorter than 100 nm (3 ppm of TOA insolation) absorbed mostly above 90 km, ionizes N2, O2, and O.

    (footnote on p.328) near 120 nm, a “narrow spectral “window”” allows penetration down to 60-90 km, ionized nitric oxide, “believed” to produce D-layer.

    radiation from 100 to 200 nm (0.01 % of TOA insolation) absorbed 50-110 km, “virtually all absorbed” in photodissociation of O2.

    radiation from 200 to 310 nm (1.75 % of TOA insolation) absorbed 30-60 km, photodissociates O3.

    longer wavelengths – 98+ % of TOA insolation – about 17 % of that is absorbed by H2O vapor.

  48. 198
    Patrick 027 says:

    last part of last comment: should cite: Wallace and Hobbs pp.328-330:

  49. 199
    Jim Larsen says:

    173 Ray said, “Say what? Uh, Dude, if this were true, would it make sense to drill in deep water? …in the Arctic? ”

    You’re confusing profit with gross margin.

    A decision to drill is based on expected profit, all the while knowing that additional production will degrade the profitability of one’s current production. Once made, the decision is not revokable. This means that fossil fuel companies only drill if the expected profit is immense, ensuring that even if prices drop profits will still be made. After the well is drilled, everything changes. The producer is locked in, profit becomes irrelevant and gross margin rules. Since gross margin is huge in fossil fuels, dropping production is insane, assuming collusion isn’t involved.

    A well drilled is a well pumped dry. The only decision point is before a single drop gets to market. It’s like software. You spend big bucks up front, and every barrel/program sold doesn’t increase costs much at all, but one can have a gross margin of 90% and still lose money. In that situation, you still sell as much as possible, even though you’re losing money.

  50. 200
    Ron R. says:

    Well I read a bit more and was commenting when suddenly the page was gone as were my comments so I’ll try again.

    I see they address at least one of my prior questions about surviving the launch by proposing shielding for each “flyer”.

    Other quotes and comments.

    At the end of their life, the flyers will have to be replaced if atmospheric carbon levels remain dangerously high


    They also say: If it were to become apparent over the next decade or two that disastrous climate change driven by warming was in fact likely or even in progress…

    The author doesn’t sound too sure about that.

    And that “replaced” part, do they mean launching another 16 trillion flyers every 50 years?? Sheesh! I’m wondering if all that debris would be a hazard to future space travel or satellites and how much of it will be coming back to earth as high-tech litter.

    The dead ones that find their way back to Earth could present a threat to Earth-orbiting spacecraft, but hopefully no greater than the annual flux of a million, 1-g micrometeorites, or the 30 million debris objects in low-Earth orbit that weigh ≈1 g. This issue needs to be analyzed…. It seems, however, that this threat could be held to a level no more than that presented by the ≈100 1-ton natural objects that hit the Earth annually.

    Hopefully? The author’s reasoning here does not at all negate the issue. In what way does one unavoidable and undesirable occurrence excuse another intentional one? That kind of reasoning is akin to tobacco companies rationalizing away the deaths of tens of thousands of people a year because, hey, that many die from non-smoking related lung cancer anyway.

    To transport the total sunshade mass of 20 million tons [16 trillion flyers and 20 million armatures], a total of 20 million launches will be needed, given flyer payloads of 1,000 kg.


    The cloud cross-section would be comparable to the size of the Earth and its length much greater, ≈100,000 km.

    Again, wow!

    And if flyer construction and transportation costs each can be held in the region of $1 trillion total, then a project total including development and operations of <$5 trillion seems also possible.

    Hmm. What started out as “a few trillion” is now under $5 trillion – and that’s IF other costs can be held down.

    It would make no sense to plan on building and replenishing ever larger space sunshades to counter continuing and increasing use of fossil fuel.

    Sure it would if they could be made better, easier and cheaper than this – sorry – this boondoggle.

    To be honest this paper reads like an advertisement. It sounds like a bad idea.

    Personally, I don’t think we should be implementing any solution that cannot be easily undone if necessary.

    Anyway, while I don’t think it’s the best idea Rob, still, thank you for the link.