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

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Comments 101801 to 101850:

  1. actually thoughtful at 14:23 PM on 10 December 2010
    Renewable Baseload Energy
    Source for PEW data above: http://www.pewclimate.org/technology/overview/buildings
  2. actually thoughtful at 14:21 PM on 10 December 2010
    Renewable Baseload Energy
    Quokka - I run a company that specializes in renewable based heating systems. So the we is me. Design temperature is -2F (-19C). Design temperature means the coldest temperature you reliably get every winter. I will publish my results in the next 6 months (in a trade journal - there is no new science here, just intelligently using current technology, with a few of my own innovations). According to the PEW Center - 51% of a buildings energy usage comes from HVAC and water heating. I found multiple sources for buildings using 39% of total US energy use was for buildings. So by cutting 1/2 of 40% by 75% we have as our total pie 15% of total US energy usage! So, following the basic rule of ethics - is it generalizable? Yes! If all buildings followed our recipe, we could cut emissions by 15% - that is basically the entire Obama commitment to climate change (obviously to weak). Now some caveats - our work reduces natural gas, electricity (for water heaters - site specific) and propane - natural gas is called the "cleanest" of fossil fuels, and propane is slightly worse, but not as bad as electricity. Not all buildings are ideal candidates for solar thermal (but there is always geothermal - more than one way to get to zero energy). However, reducing electrical loads is at least as easy. Obviously reducing the need for heating/cooling and electrical use is the easiest path to reducing building loads. But we can retrofit a building with solar space heating at a similar-if-not cheaper cost than replacing all the glass and upgrading all the insulation (both, with a smaller system from us is most preferred). And these improvements pay for themselves over time. A building's mortgage is fixed (does not go up with inflation) but fuel prices are variable (and in fact, for the last 43 years (as far back as the data goes) have increased at roughly double the average inflation rate (fuel rate of inflation is 6.5% per year). I am 100% against greenwash - and this is, indeed planetary scale. As in think globally, act locally. One greenwash myth is that we need utilities and governments to do this *for* us. Not true. Each of us can and should take action (as should utilities and governments). Our lives are improved by this act. There is a HUGE satisfaction to taking control of your own energy destiny in your own home or place of work. Try it before you talk it down.
  3. A Cloudy Outlook for Low Climate Sensitivity
    Daniel@ 120: I posted the url so that people could read the paper. The url you posted takes you to the publisher, and is not readable unless you are a member. The paper deals with observed cloud feedback verses modeled cloud feedback. Rather than inflect my opinion, I present the literature for each to interpret. As far as 119: We shall see.
  4. A Cloudy Outlook for Low Climate Sensitivity
    Re: Camburn (118) Generally it is both good form to provide some insights (if you have any) into what readers of a linked source can expect to find therein and to provide a link to the published version of the paper, not a submitted version. The Zhang paper is fairly long in the tooth (submitted in 2007, accepted in 2008, published in 2009) for a cloud paper. Compare and contrast it to this recent paper by Dessler et al (to which Albatross has already linked to previously in 114 and to which dana1981 has then referred to above at 117) which find a net positive contribution from clouds. (119) Enough data has come in on 2010 to make even the portion available for 1995-2010 (inclusive) statistically significant. So you are wrong on that. The Yooper
  5. Stratospheric Cooling and Tropospheric Warming
    Joe Blog @196, having now understood what you are saying, I will not procede to criticize it. First, although the mechanism you describe sounds plausible, you fail to account for the characteristic rates characteristic rates of convection and radiant transfer. Specifically, while it only takes a few hours to restore thermodynamic equilibrium in the atmosphere by conduction, it can take as much as 50 days to do the same by radiation. This difference of rates is the primary reason why convection dominates radiation as a means of energy transfer in the atmosphere, and is still relevant at the tropopause. Given the example in 195 of a warm air parcel rising to 8km altitude, this means it would reach an equilibrium temperature by radiation over the period of about a month, or more. But it would still be able to reach an equilibrium temperature with the surrounding air in a few hours by convection, ie, by continuing to rise. Consequently, on these grounds, we would expect convection still to dominate as a heat transfer mechanism within the atmosphere. Second, radiant transfer is related to the fourth power of temperature, while heat conductive heat transfer is related to the difference between the temperature of the heated or cooled air parcel (Tap) and the temperature of the ambient air (Te) by the relation such that, a = g(Tap-Te)/Te , where a is the acceleration on the air parcel, g is the gravitational acceleration, and a is the acceleration of the air parcel. Therefore, given a 1% rise in temperature, we would expect heat transfer by convection to increase by about 1%. Heat transfer by radiation, in contrast, should increas by about 4%. Because radiant transfer becomes more effective with rising temperature, if radiant tranfer dominated, we would expect a rise in temperature to decrease the altitude at which radiant tranfer first started to dominate. Consequently, if the altitude of the tropopause where determined by where radiant energy started to dominate for heat transfer, then incraseing atmospheric temperature should decrease the altitude of the tropopause. Instead, the tropopause is highest in the tropics and lowest at the poles. Indeed, even cold fronts will lower the tropopause. "As can be seen in the figure above, the tropopause altitude steadily drops from about 12.5 km to 11 km as the DC8 flies west from The Azores toward a cold front in the western Atlantic Ocean. At ~10:15 UT there is evidence of stratospheric tracers (O3, NOy up, CO down) from in situ sensors. At the same time, the tropopause altitude drops abruptly more than 1 km and MTP sees a warm finger of air extending through this tropopause drop, apparently because the descending stratospheric air is being adiabatically heated. Later, at 11:17UT the Langley Research Center DIAL lidar saw the beginning of a stratospheric intrusion at the same time that MTP saw a second tropopause altitude drop" (Caption quoted from source.) Finally, I think my comments about the mesosphere in 193 above are still relevant.
  6. A Cloudy Outlook for Low Climate Sensitivity
    Steven: As far as staticistical temps.....2010 is not over. I still stand by my statement. Also, 93% does NOT cut it.
  7. A Cloudy Outlook for Low Climate Sensitivity
    This paper addresses cloud feedback: http://www.esrl.noaa.gov/psd/people/dezheng.sun/dspapers/Sun-Yu-Zhang-JC-revised.pdf
  8. Renewable Baseload Energy
    395 actually thoughtfull Who is this "we" and where does this "we" live? If you want this sort of thing to be taken seriously, provide some data and references. As always, the only thing that actually matters is planetary scale emissions reductions not feel good greenwash.
  9. Stratospheric Cooling and Tropospheric Warming
    Tom Curtis lol, yup, but i did say transparent. Not non radiating, so this energy could be radiated away by magical atmosphere. But i recall coming to a similar conclusion thinking about a non radiating atmosphere.
  10. actually thoughtful at 12:06 PM on 10 December 2010
    Renewable Baseload Energy
    I should point out however, that solar water heaters can heat your home. Most people think about heating hot water - we are able to get over 75% of annual space heating and hot water from the sun. Right now, today. With payback less than a decade (and less than 20 years without rebates - meaning it is financially viable/smart now).
  11. Stratospheric Cooling and Tropospheric Warming
    Joe Blog @214, heat is also passed from surface to atmosphere by evaporation and transpiration. This, together with conduction would be enough to heat the lowest layer of the atmosphere to surface temperature, even in the absence of radiant heat transfer. And that in turn would be enough to generate convection. Even if only conduction were available, that would still raise the lower atmosphere's temperature to near surface temperatures. Because conduction is a slow method of heat transfer, the lower atmosphere would not have a large day-night cycle in temperature, although land surfaces would have a very large cycle. But even this slow method of heat transfer would heat the entire atmosphere up to at least the mesopause in the absence of any absorption of radiant energy by the atmosphere.
  12. Stratospheric Cooling and Tropospheric Warming
    Bob @201, as you surmise, temperature in the stratosphere is partially controlled by the mixing ration of Ozone to CO2, and if the flux of UV was constant with altitude, we would expect the highest temperature in the stratosphere to be where the highest mixing ratio was found. However, UV flux is not constant with altitude. Most UV-a, the most energetic form of UV, is absorbed above the level of maximum O3, apparently by the breakup of O2 (VGT @211). Considering UV-b, the next most energetic form of UV, nearly half is absorbed above 30km. Combined with the energy from UV-a, this should be sufficient to explain the temperature profile in the stratosphere. An interesting consequence of reduced O3 is that UV should penetrate further into the stratosphere. This should show up as a cooling at higher altitudes as they absorb less UV, but a warming at lower altitudes as more UV penetrates to the lower levels to be absorbed. The result is that in the lowest levels of the stratosphere, CO2 cooling is almost balanced by an ozone based warming, while in the upper levels they reinforce each other. PS: In preview, my first two images are not showing. I am leaving them in in case this is just a temporary bug, but in the mean time they can be found at the wikipedia article on the ozone layer.
    Moderator Response: [Daniel Bailey] Fixed links. TIP: When linking to Wiki graphics, make sure you click on the graphic itself, bringing up the page with just the desired graphic and no text. If you see text still, click on the graphic again to bring up the source storage position for that graphic. That should take care of it.
  13. Renewable Baseload Energy
    @392 archiesteel
    Re: RSVP's last bunch of tro...I mean, comments, I'd be curious to hear how quokka would respond to the "argument" put forth.
    I'd say RSVP is numerically challenged. Some things don't pass the smell test. But if pressed, I would suggest that the effects of a rise of 2-3 degrees in global temperatures on renewables is most likely unknown. Changes in cloudiness could affect all types of solar but which way?, PV might be slightly less efficient due to temperature, CSP relying on a heat engine may be slightly less efficent, wind - who knows? Regional climate change might be the major factor. Overall effect likely to be small. As for solar hot water systems heating the planet - don't make me laugh.
  14. Stratospheric Cooling and Tropospheric Warming
    Joe Blog at 214 And on refection I also fully with 214
  15. Ice data made cooler
    JK: the application file is Flash (.swf) which can be run by any browser that supports a flash player plugin. The code is written in Flash's scripting language called ActionScript. Contact me at my blog (http://www.brightstarswildomar.blogspot.com/) and we can figure out how to exchange files. jg
  16. Stratospheric Cooling and Tropospheric Warming
    Joe Blog at 215 I fully agree with that.
  17. Ice data made cooler
    JG: thanks for the comment. of course now everything is clear. The programme I was requesting is the one which generates the graph ... (is it in Java or Javascript or C++ or fortran?)
  18. Ice data made cooler
    RSVP, Oxygen is not very soluble in water while carbon dioxide is very soluble in sea water. Therefor the ocean can outgas a lot of CO2 but not much O2. In addition, since the amount of CO2 in the atmosphere is small relative to oxygen, releasing the same amount of both gases would substantially raise CO2 while leaving O2 essentially unaffected. A person with your level of understanding of science should refrain from speculating about changes in the climate and atmosphere on a science blog.
  19. Ice data made cooler
    The relative important of various feedbacks the magnify the NH milankovic cycle is still significant area of research as far as I know. The lack of land in SH temperature zone has to involved to explain why there global glacial cycle isnt a seesaw between NH and SH. Beside ocean feedbacks, there is of course albedo (limited in SH because little land available to cover with ice. Australia is too low and too far north) but also note the biogenic methane is clearly a feedback. Swamp methane,(increases with warm, decrease with cold) which then oxidises to CO2. The effect of vegetative change on the CO2 feedback also appears to be significant(see Kohler et al
  20. Models are unreliable
    Chris, first note that models are scenarios based on amount of GHG in the atmosphere. ie if CO2 is 450ppm, then climate looks like x. Now if against all paleo icecore data we have situation whereby warming world REDUCED pulls more CO2 from atmosphere than a cooler one, the result would be that the emissions scenarios need revised. ie for a given rate of fossil fuel consumption, then the rate of accumulation of CO2 in the atmosphere would reduce. However,I am unaware of any modern or paleo data to support the idea that increased temperature would decrease CO2 - in fact all of the evidence I have seen to date shows the opposite.
  21. A Cloudy Outlook for Low Climate Sensitivity
    Damn, I wish Dessler's paper had come out a week earlier! Maybe I'll have to do a new blog post as an addendum to this one...
  22. Ice data made cooler
    Hi Tony, thanks for the reply. Yes, having done a fair bit of reading on Milankovitch Cycles, I can honestly agree that it is *extremely* robust-& fits extremely well into the climate cycles of at least the last 1 million years. My question was more seeking clarification of exactly how Milankovitch cycles work. Judging from John's reply, I was close, but not quite on the mark ;). Certainly the uniformity of recent warming events is yet more proof that Milankovitch cycles cannot be blamed this time around ;)!
  23. Ice data made cooler
    jp Excellent work! Don't worry about comment #3. I don't have the exact numbers at the moment but the same release from the oceans that makes CO2 raise from 250 to 400 ppmv as a product of the warming process makes oxygen, for instance, to rise from some 209,000 to 209,030 ppmv, so the conclusion is pretty obvious: much below other error margins. About eccentricity, Laskar et al have taken care of it, so the conclusion is: done. There are a few things that ""should"" be considered along the content of comment #3, but I'll better comment in your blog as many "eager skeptics" use to hang raw comments in sites like this just to have them corrected so they can publish them in other sites as arguments (the "throw everything at the wall and see what sticks" strategy described here by dana1981)
  24. Ice data made cooler
    RSVP: Thank you for elaborating. I'm not qualified to give you an answer. I can only make a comparison. Forgive my not looking the name up, but there are a couple lakes in West Africa notorious for their sudden outgassing of CO2 that has sufficated nearby inhabitants. Somehow it was possible for thsese bodies of water to build up CO2 in ratios not typical of the atmosphere and then release it, also in ratios not typical. I have a few articles that describe the role of outgasing and the ocean's biological pump. One mentioned that a mechanism building up CO2 could be the reduction of ocean's biologoical pump. As I understand the biological pump, it's the growth of phytoplankton that take up CO2 die and sink to the bottom. A lot of recycling of nutrients happens in the 100 meters before the dead plankton sink, but the net sum of what gets through and buried can change, and this process is selective. In fact the scientific literature is full of processes that selectively operate on different chemicals and elements. Thank you for encouraging me to ponder this. jg
  25. Steven Sullivan at 08:34 AM on 10 December 2010
    A Cloudy Outlook for Low Climate Sensitivity
    Camburn @64:"1. Statistically, and this is important unless you want to throw statistical analysis out with the wash, we have not warmed for the past 15 years." Leaving aside the disingenuousness of totally ignoring a *93%* level of significance for said warming: Start from when Phil Jones made that comment, and go back to 1995 -- *16* years instead of 15. Voila: warming, at or better than the 95% significance level. Or: Start from when Phil Jones made that comment. Go back to 1995 (15 years) Add the rest of 2010 since he made that comment. Voila: warming at or better than 95% significance level. Still feeling lucky, Camburn? Btw, I can see that at this point, having lost on the substance of Dana post, you're just robotically going down the same old well-worn list of 'skeptic' talking points. The Jones quote; the Trenberth quote; can 'hide the decline' be far behind?
  26. Ice data made cooler
    @RSVP: you seem to be ignoring the gigatons of anthropogenic CO2 being released in the atmosphere each year...
  27. We're heading into an ice age
    @NQoA: "That's pretty much what the "Climate Change Deniers" have been saying all along." Actually, that isn't true. There are still many deniers/politically-motivated skeptics who still dispute we are in a warming trend. Indeed, many of those who have been trying to prop up the failed manufactured Climategate scandal (which has now been thoroughly eclipsed by Cablegate) are saying just that. The fact that you seem to believe warming should be linear is also a sign you are gravely mistaken: complex systems do not react in linear fashion. Look at the Stock Market if you don't believe me...
  28. Ice data made cooler
    jg #8 "The release of oxygen tempering the effect of CO2 releases is new to me." To me too, since I made it up on the fly. I am referring to the fact that all components of the atmosphere dissolve in water, so when CO2 is released as a function of warming so is everything else, thereby increasing partial pressures of all gases. If all partial pressures increase in unision, its not clear why the ppm of any one component should go up. In fact, you would expect the partial pressure of the more abundant gas to go up higher in proportion to its overall percentage, so that in fact ppm of CO2 being so small should go down. But I am no expert, so this is pure conjecture bases solely on skeptical logic.
  29. Ice data made cooler
    Anyone wanting to exchange files can contact me at my blog. Go to http://www.brightstarswildomar.blogspot.com/.
  30. Ice data made cooler
    paulm, Good suggestion. I'll add that feature to the list. There some enjoyable irony in that I built this program so that I wouldn't accidently mix up time periods. JK: The insolation values are for June (northern hemisphere) and December(southern hemisphere). So though both plots are of the same latitude, one is what you would measure at one point in Earth's orbit, and the other, six months later. So as long as there is some eccentricity, these values would be different, that is, except for times when the equinoxes are at right angles to the semi-major axis, e.g., at 135kyr (second diagram). When I first collected the data, I included plots that could compare +65 June to -65 June, and quickly decided this wasn't as valuble of a comparison as N. Summer (Jun) to S. Summer (Dec); However, I may add these graphs. Your request for a copy of the program--that was for Mike's global warming game, correct? jg
  31. Ice data made cooler
    Hi Mike, this is a very interesting and fascinating program. Thank you. Can I get a copy of it? Just for teaching astronomy and climate physics. However I do not understand the following: When you - only - click insolation on 0º NH and simultaneously on 0º SH - I would expect equal plots. However they have a "phase shift" of - say it simple - 180º .. Could you explain that please? kind regards JK PS: I made a screenshot of this phenomenon - how could I provide that to you?
  32. Models are unreliable
    It appears that not quite half of the photosynthesis occurring on the earth is in the oceans. Search for 'Global' http://en.wikipedia.org/wiki/Primary_production "Using satellite-derived estimates of the Normalized Difference Vegetation Index (NDVI) for terrestrial habitats and sea-surface chlorophyll for the oceans, it is estimated that the total (photoautotrophic) primary production for the Earth was 104.9 Gt C yr−1.[12] Of this, 56.4 Gt C yr−1 (53.8%), was the product of terrestrial organisms, while the remaining 48.5 Gt C yr−1, was accounted for by oceanic production." So, I hope to read that these negative CO2 feedback effects are also being modeled for algae as well. Chris Shaker
  33. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio at 04:25 AM The ozone's thinning can and has been quantified, variable UV through the solar cycle, also effects stratospheric T's, UV is the most variable wave length through the cycle. But smarter people than me, have done studies on these things... there is that paper that by Johanna Haige, that a thread was done on here that may impact these. But the reason why raising co2, should cause the stratosphere to cool, is because it causes more energy to be lost from the stratosphere through radiation. VeryTallGuy - 212 Yes (-:
  34. Models are unreliable
    Older research on the topic, and it appears, more controversy http://www.sciencedaily.com/releases/2007/12/071211233441.htm "Interestingly, warming temperatures in response to rising carbon dioxide levels could make more nitrogen available, said Xiaojuan Yang, a doctoral student in Jain’s lab. This factor must also be weighed in any calculation of net carbon dioxide load, she said. “Previous modeling studies show that due to warming, the soil releases more carbon dioxide through increased decomposition,” she said. “But they are not considering the nitrogen effect. When the soil is releasing more CO2, at the same time more nitrogen is mineralized. This means that more nitrogen becomes available for plants to use.”" Chris Shaker
  35. Models are unreliable
    Found several articles lately about plant growth providing negative feedback against CO2 increases, including this recent NASA model update. I've also read a paper saying that rising temperatures will also make more nitrogen available for plant growth. These new models seem to make increased temperatures from a doubling of CO2 much more modest than previously claimed. Do these new models also include the negative feedback from the ocean equivalents of green plants, ie - photosynthetic creatures like algae, diatoms, coral, etc? The huge biomass in the oceans would seem to be more important than terrestrial plants? The Science Daily report on the NASA study http://www.sciencedaily.com/releases/2010/12/1012080 Here is the abstract from the paper http://europa.agu.org/?view=article&uri=/journals/gl/gl1023/2010GL045338/2010GL045338.xml&t=gl,bounoua "Several climate models indicate that in a 2 × CO2 environment, temperature and precipitation would increase and runoff would increase faster than precipitation. These models, however, did not allow the vegetation to increase its leaf density as a response to the physiological effects of increased CO2 and consequent changes in climate. Other assessments included these interactions but did not account for the vegetation down‐regulation to reduce plant's photosynthetic activity and as such resulted in a weak vegetation negative response. When we combine these interactions in climate simulations with 2 × CO2, the associated increase in precipitation contributes primarily to increase evapotranspiration rather than surface runoff, consistent with observations, and results in an additional cooling effect not fully accounted for in previous simulations with elevated CO2. By accelerating the water cycle, this feedback slows but does not alleviate the projected warming, reducing the land surface warming by 0.6°C. Compared to previous studies, these results imply that long term negative feedback from CO2‐induced increases in vegetation density could reduce temperature following a stabilization of CO2 concentration." Chris Shaker
  36. Stratospheric Cooling and Tropospheric Warming
    mars at 19:39 PM on 9 December, 2010 says "The atmosphere at low levels is transparent to nearly all of the incoming radiation." I took that as a given, i was talking about LW. Mars says "The atmosphere is heated by contact with the surface. As a result a parcel of air close to the ground forms which is warmer than the surrounding air." The air is heated, by conduction and radiation, and as a result of the air being opaque to LW radiation in the lower troposphere, this energy is trapped, if it was transparent, it would simply pass through at the speed of light. There is nothing wrong with your description of convection, but the properties of the lower atmosphere are taken as a given, radiation is not considered, because the lower troposphere is opaque to the passing of LW, but at 6000m, radiation is the dominate means of energy transport(this is the average altitude of equilibrium with incoming and out going energy), not the sole, but dominate. As you rise further, the atmosphere becomes more and more transparent, and convection less and less important.
  37. A Cloudy Outlook for Low Climate Sensitivity
    Ha! And here's some additional commentary from Dessler, addressing Spencer directly. My cup runneth over. Especially this part:
    And as far as my interest in influencing the policy debate goes, I’ll just say that I’m in College Station this week, while Dr. Spencer is in Cancun. In fact, Dr. Spencer had a press conference in Cancun — about my paper. I didn’t have a press conference about my paper. Draw your own conclusion.
  38. It's cosmic rays
    muoncounter, the low frequency is a good point. I don't what the frequency history is, but likely it varies between zero and small. But it is not random since the galactic structure was not random over time and our transit through the galaxy does not take us into random amounts of leftover particles. It is quite unpredictable, although not completely unpredictable. They are modulated by solar activity and of course solar activity itself has other effects, so it is worth studying and using GCR as a proxy. But this thread is about cosmic rays and (my addition) the effect they could have on sensitivity. The fact of CO2 warming is not in question here (or at all), just sensitivity and I would greatly appreciate your opinion on my final sentence in #29.
  39. A Cloudy Outlook for Low Climate Sensitivity
    Hot off the press: Dessler (2010) "Estimates of Earth's climate sensitivity are uncertain, largely because of uncertainty in the long-term cloud feedback. I estimated the magnitude of the cloud feedback in response to short-term climate variations by analyzing the top-of-atmosphere radiation budget from March 2000 to February 2010. Over this period, the short-term cloud feedback had a magnitude of 0.54 T 0.74 (2s) watts per square meter per kelvin, meaning that it is likely positive. A small negative feedback is possible,but one large enough to cancel the climate’s positive feedbacks is not supported by these observations. Both long- and short-wave components of short-term cloud feedback are also likely positive. Calculations of short-term cloud feedback in climate models yield a similar feedback. I find no correlation in the models between the short- and long-term cloud feedbacks."
  40. We're heading into an ice age
    #168: "Argentine glacier advances... " Missed this little tidbit from the lead paragraphs of the article: Argentina's Perito Moreno glacier is one of only a few ice fields worldwide that have withstood rising global temperatures. Nourished by Andean snowmelt, the glacier constantly grows even as it spawns icebergs the size of apartment buildings into a frigid lake, maintaining a nearly perfect equilibrium since measurements began more than a century ago. -- emphasis added So to say that a glacier "advances" when it is merely maintaining equilibrium is a tad disingenuous. However, since NQoA has such definite opinions in the context of this thread, it would be interesting to see how he lines up on the question of 'are we heading into a new ice age?' Especially interesting if he could provide some actual substantiation (beyond a mis-read of a news clip) for what must be very strongly-held opinions. Because that would provide him some credibility; without credibility, opinions are ... just opinions.
  41. It's albedo
    #16: "Dr Malcolm" And who wrote Jurassic Park? Same guy who did this bit of work. At last we see how those deniers work, moving so seamlessly that one cannot tell where their non-fiction ends and their fiction begins.
  42. A Cloudy Outlook for Low Climate Sensitivity
    It looks like Spencer is pounding the table again today that "hen cloud changes cause temperature changes, it gives the illusion of positive cloud feedback – even if strongly negative cloud feedback is really operating!" I think Spencer's all wet, but I haven't seen a thorough analysis of this line of argument. Spencer basically argues that climate scientists have cause and effect all mixed up. Unlikely, but an interesting line of thought. I have not seen a really good response to e.g. Spencer & Braswell- is there one?
  43. It's cosmic rays
    #29: "they keep going back to solar and use GCR proxies as a solar proxy." Because solar magnetic activity is what causes the observed variation in GCR frequency. Are you reading anything in this thread and following links that we provide? "Although GCR's are modulated by solar activity, they are their own animal." What animal? GCRs are infrequent and random; they come from times long ago and places far away. The only important feature of GCRs in this context is that they "are modulated by solar activity", which is what you questioned one sentence earlier in your comment #29! #26: "Events like SSW" OK, so I looked at the website you linked, which is pretty nice. It would be interesting if you would try to match up the dates of their SSW events with anything else. However, there are fewer than 30 events in their entire database, which runs back to 1958. How much warming are we supposed to be getting from fewer than one event per year? I suppose if you pile up enough of these disparate straws, you will indeed be able to put together a modest-sized strawman. But it is stunning that one can cling to 'this might' and 'that could', when the answer, my friend, is blowing in the increasingly CO2-enriched wind (apologies to Mr. B. Dylan). Unless it is some preconceived idea that it just can't be CO2. In which case, you should be reading more here at SkS.
  44. Ice data made cooler
    Marcus The influence of Miankovic Orbital variations on Earth Climate are well understand and are robust. This was resolved with the publication of a paper in the 1970's by Hays and Imbrie. You can read about this in Imrie's book and in a book by William Ruddiman. I'm at work so can't provide details but this is enough if you hit amazon. Orbital variations do not change the solar radiation incident on the Earth over the year. They only change the distribution of that energy in time, depending on which season the Earth happens to be close to the sun (it is an eliptical orbit) and the tilt of the Earth relative the the plane of the Earth orbit. It turns out that when the solar insolation (look this word up) is weakest in the summer at about 65 degrees North Lat, then the winter snow accumulation will not melt very well and thus the ice sheet grows. Croll had the idea that orbital variations caused the ice ages but he thought that cold winters would do the trick. Milankovic's great insight was that it was cold summers which did the deed. All very fascinating and Imbrie has all the history of this discovery as well as being one of the discoverers Tony
  45. It's cosmic rays
    Riccardo, thanks for the link. That paper is broad, not deep, but I agree with their conclusion that it is inconclusive especially without good GCR proxy data earlier than the present and 130k interglacials. What is a little weird about the paper is that they keep going back to solar and use GCR proxies as a solar proxy. Although GCR's are modulated by solar activity, they are their own animal. My guess looking at fig 8 is that an interglacial requires both low GCR plus northern hemisphere sun (the other thread), it can't happen with just one or the other.
  46. Ice data made cooler
    Great stuff. How difficult would it be to ad two windows so you can inspect two period at the same scale....
  47. Renewable Baseload Energy
    Just to be clear, even though Toshiba owns the majority of Westinghouse Electric Company, it is still based in the US.
  48. Steven Sullivan at 05:11 AM on 10 December 2010
    How to explain Milankovitch cycles to a hostile Congressman in 30 seconds
    re: Santer at ~min 35 of http://www.c-spanvideo.org/program/ChangePa Santer starts his rebuttal with: "Dr. Michaels' analysis is wrong; it's just completely incorrect." THAT is how it should be done.
  49. Steven Sullivan at 04:53 AM on 10 December 2010
    How to explain Milankovitch cycles to a hostile Congressman in 30 seconds
    archiessteel "If anything, professor Alley's responses were still too wordy (bald spot excepted). When the (very partial) congressmen started his nonsense about Mars experiencing the same climate change as we do, he should have simply said it isn't. When demagogues make statements which they can't prove, you can simply call them on it. This puts the burden of proof on them, and since they *can't* support that position (due to a lack of facts) they'll simply stop using it as an argument." +1 We scientists have to be able to parry the rhetorical tactics that troglodytes like Rohrbacher use. That means *short, declarative* statement first -- that's right/wrong, that's true/false -- FOLLOWED BY the explanation. Alley too often doesn't do this. He went right to the explanation, often obliquely.
  50. Ice data made cooler
    Albatross, Thank you, and yes. I'll add the features you request. I'll probably have a new version released by the end of the holiday break. jg

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