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Comments 69501 to 69550:

  1. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    That's some dramatic graph.
  2. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    I have a question - was the original figure in Monckton Pink or did you recreate it that way? ;) Happy Thanksgiving to all here who celebrate it.
    Response: [JC] It's the original colour. So "Monckton pink" is the official term for it now, is it?
  3. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    perseus : "I doubt a 'zero' carbon economy will be as easy as you suggest. It will get progressively more difficult and expensive as renewable penetrations become higher, 'carbon leakage' becomes significant and we obtain diminishing returns from improving thermodynamic efficiencies further" Again, I agree with you. We all remember nuclear energy "too cheap to meter" and other unrealistic optimist projections, very usual in energy litterature since the XIXth century. Energy transitions are slower than we like to imagine, and that's true since the first wood to coal transition of industrial period. We can accelerate the pace by political will, but there are heavy constraints from the installed energy infrastructure and their socio-economic implications. Furthermore, electricity is just a small part of the problem because fossil fuel are also used for transport and heat, and they are uneasy to substitute in metallurgy, production of cement, plastic, glass, etc. Of course, scientists work on alternative solutions in all process, but the deal for a 450 ppm scenario is not just to replace a coal plant by a wind or solar farm. In last resort, such considerations also depend on the total energy production we aim, which itself depends on material quality of life and growth targets (your paper!). Humanity consume now approx. 500 EJ/year so, if you wish it consumes 250 EJ/year in 2050, it will be far more easy to achieve a zero carbon economy. But if you target 750 EJ/year at the same year, no hope with current technologies – we are not even sure there would be enough cheap fossil reserves to reach and sustain this level! Concerning "austerity" (we will probably discuss it with the 2nd part of the paper), the problem seems to me on first approach : who decide of the 'fair' level of individual, national or global austerity ? As we can observe in climate negociations rounds, it's as uneasy to convince emerging countries that they are already sufficiently "rich" as it is to convince rich populations policymakers that they must downsize their GDP for climatic reasons. And as we observe in everyday life, few people diminish spontaneously each year their carbon or energy footprint so as to divide it by 4 in 30 years.
  4. Climategate 2.0: Denialists Serve Up Two-Year-Old Turkey
    I think the issue of whether publicly funded science should be open is more complicated. Sometimes governments fund research/science with the idea of selling the concepts to a commercial company later or sell the technology. If you made everything public, then such projects could not be sold off later. The other issue is national security. Indeed weather forecasting can be considered a military intelligence issue. Better forecasting can result in military advantage during conflict or used to predict the enemies actions. It can also be used in misinformation and counter intelligence. The issues are wide ranging and far from simple, so complete open access to publicly funded research is unlikely, only special cases such as climate science are likely to be published.
  5. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Kevin C, It was warmer than present in Greenland during the MWP according to Kobashi et al. 2011 (includes Jason Box). Around 1100 AD it was warmer than present for most of a 50 year period and then around ~700 AD it was significantly warmer than present for ~100 years. (More than 1°C for most and 2°C warmer for a short period) (Nearly the difference from present to the LIA in Greenland).
    Response:

    [DB] An open copy may be found here:

    http://www.leif.org/EOS/2011GL049444.pdf

    Section 5.3 is relevant to this discussion.

  6. Ice age predicted in the 70s
    I just ran across this paper, (Damon & kunen 1976) "Global Cooling?" In the abstract is the following: Because of the rapid diffusion of CO2 molecules within the atmosphere, both hemispheres will be subject to warming due to the atmospheric (greenhouse) effect as the CO2 content of the atmosphere builds up from the combustion of fossil fuels. Because of the differential effects of the two major sources of atmospheric pollution, the CO2 greenhouse effect warming trend should first become evident in the Southern Hemisphere. The socioeconomic and political consequences of climate change are profound. Science 6 August 1976: Vol. 193 no. 4252 pp. 447-453 DOI: 10.1126/science.193.4252.447 Global Cooling? It seems that not only was the consensus recognizing global warming, but there was a warning with respect to socioeconomic and political consequences.
  7. Arkadiusz Semczyszak at 00:08 AM on 25 November 2011
    Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    For me, work Kinnard (2011) only authorizes them to this conclusion: “Our reconstructed warming of ~2°C since the LIA matches the reported temperature increase of the Arctic Atlantic Water Layer (AAWL), obtained from observational data of the past ~120 years (21) (Fig. 3C). At present, there are no subcentennial-scale open ocean proxy data series available to document the temperature evolution of AAWL in the Arctic Ocean proper in the preceding two millennia.” and: “Although we cannot quantify from our data the variability of previous AW inflow to the Arctic by volume, our temperature data series and the above observational link suggest that the modern warm AW inflow (averaged over two to three decades) is anomalous and unique in the past 2000 years and not just the latest in a series of natural multidecadal oscillations.” And what of the “millennium oscillations”? Without these data (first citation) - how can so much speculation: "We know that the Arctic is the most sensitive region on the Earth when it comes to warming, but there has been some question about how unusual the current Arctic warming is compared to the natural variability of the last thousand years," said Marchitto, also an associate professor in CU-Boulder's geological sciences department. "We found that modern Fram Strait water temperatures are well outside the natural bounds." I think I wrote a clear and without errors ...
  8. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Thanks Rob: That was the information I was after. AnotherBee: Thanks for clarifying the distinction between the mythical warm Greenland and the real one. The version in my head was much closer to the real one, but given how these myths propogate I should have been more precise in my question. So your comment was well made.
  9. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Arkadiusz Semczyszak - I know it's the language barrier, but I always find it hard to figure out what you're on about. But I'll have a stab at it. - Error bars. That's the large guava-coloured area in figure 1. Notice how it enlarges the further back in time one goes? - Kinnard (2011) state: "These results reinforce the assertion that sea ice is an active component of Arctic climate variability and that the recent decrease in summer Arctic sea ice is consistent with anthropogenically (human-caused) forced warming" - Kaufman (2009). Yup, orbital factors saw a decline in Arctic summer temperatures from the Holocene Climatic Optimum onwards, until humans started burning fossil fuels like crazy. Spielhagen (2011) state: "We find that early–21st-century temperatures of Atlantic Water entering the Arctic Ocean are unprecedented over the past 2000 years and are presumably linked to the Arctic amplification of global warming."
  10. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Kevin C - I suspect that your recollection is wrong, or, at least, misleading. The narrative we remember for the Viking Greenland settlements goes "The Vikings farmed Greenland, therefore it must have been much warmer. Later the settlements got buried under glaciers." The first part of that is correct, but the rest of the narrative is wrong. They did farm, but they farmed in two settlements in limited coastal fringes, and it was worse-than-subsistence farming (because the farming and building eroded the fragile top-soil). The same sort of farming seems to have been possible for much of the intervening time, therefore the farming cannot be taken as direct evidence of warmer conditions. The Viking settlements did not get buried under glaciers (google Hvalsey Church). One got burried under wind-blown sand. Thus the failure of the settlements cannot be taken as direct evidence of cooler conditions.
  11. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    perseus, one of the main reasons for the disproportion in male/female births is selective terminations. One of the main objectives of a focus on later family formation is that it actually requires a higher valuation of women's work and worth before general social and economic improvements. So instead of sitting back and waiting for better health and increasing prosperity to advance the causes of lower birth rates and improving women's status, you do the status and education first. And this always leads to better health for children and the community at large. Hey presto. Fewer children born further apart and all much healthier than before. There's at least one program working very well in Africa where the focus is on education for girls and later marriage for both men and women. One surprising outcome of this, then not so surprising when you think about it again, is that the boys are tremendously relieved that they don't have to take on the burdens of providing for a family as soon as they leave school. Everyone wins.
  12. Arkadiusz Semczyszak at 22:48 PM on 24 November 2011
    Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    As usual: "shortcuts" (even for the post - definitely “too big”). If the authors in the abstract of their work they put such a statement : „... although extensive uncertainties remain, especially before the sixteenth century ...” It is worth mentioning … although. Of course, the authors mainly say that: „...both the duration and magnitude of the current decline in sea ice seem to be unprecedented for the past 1,450 years.” but they add that there are doubts - the margin of error. “... and may result from nonlinear feedbacks between sea ice and the Atlantic meridional overturning circulation. These results reinforce the assertion that sea ice is an active component of Arctic climate variability and that the recent decrease in summer Arctic sea ice is consistent with anthropogenically forced warming.” - write Kinnard et al. 2011. Granted, with the addition that this is not limited to: „recent decrease” and „anthropogenically forced warming.” Kaufman et al., 2009 argued that: in the period between 5600 and 3600 years BP (0 BP = calendar year 1950) energy flows in summer (JJA) at 65°N was reduced by 7.1 W • m-2 - demonstrating the fundamental role orbital factor in creating the natural decreasing trend in Arctic temperatures. The Earth now began to "orbit" closest to the Sun during the year in January - instead of in September as it did 7 thousand. years ago ... So for the past thousands of years in the summer months, gradually decreased the intensity of sunlight “arriving” at the Arctic. Summer Arctic became cooler at a rate of 0.2°C per thousand years. It should be noted however that this trend was many times interrupted for 200 years and even 400 years (by the trend positive) just through: „... nonlinear feedbacks between sea ice and the Atlantic meridional overturning circulation ...” - changes in amount of heat transported to the Arctic along Atlantic waters. We do not know precisely reasons for these historic natural disturbances. Spielhagen et al., 2011.: “Northward-flowing Atlantic Water is the major means of heat advection toward the Arctic and strongly affects the sea ice distribution. Records of its natural variability are critical for the understanding of feedback mechanisms and the future of the Arctic climate system, but continuous historical records reach back only ~150 years.” "Disturbances" trend can be so natural, and the current unprecedented "disturbance" questionable. The Kaufman “unprecedented” - it was one of the biggest disputes in science in recent years.
    Response:

    [DB] The prudent reader will note that in this discussion of Arctic Sea Ice (being by definition at sea level) Arkadiusz introduces a common "skeptic trick"/technique of introducing data from a local ice core in Greenland to "muddy the waters".  The issue, beyond the core data representing but a single geospacial location and thus by itself not representative of the whole (and much larger) region in which it resides, is that the core is near the Greenland summit (in order to get the deepest profile of the ice possible) and therefore at an elevation of over 2 miles above sea level.

    Permissum lector caveo (let the reader beware)...

  13. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Kevin C - This global map is from Mann (2009) and is compared to a 1961-1990 baseline. Much of the present summer sea ice retreat seems to be from warm Atlantic water moving into the Arctic and getting at the ice from below. There's simply much, much more warm water available in the Atlantic today. Both Kinnard (2011) and Spielhagen (2011) show this anomalous ocean warming.
  14. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Yes, I was surprised. I had it in my head that there was real evidence of Greenland being significantly warmer at some point during the MCA, although the effect was localised. Does this mean that it was sufficiently localised not to cover the arctic too, or is my recollection wrong?
  15. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    Kevin I doubt a 'zero' carbon economy will be as easy as you suggest. It will get progressively more difficult and expensive as renewable penetrations become higher, 'carbon leakage' becomes significant and we obtain diminishing returns from improving thermodynamic efficiencies further. I fear that in placing all our eggs in the same environmental technology basket we risk the same over optimism as when we predicted 'cheap' nuclear energy, routine space flight and artificial intelligence. I'm not saying these won't happen eventually but we need to combat AGW now to avoid tipping points, and our best chance is to tackle it on several fronts. Good points in posts 4 and 5. However, austerity tends to be relative not absolute. We already have more than enough in the developed world. It is hardly unreasonable to expect people to avoid waste and excess and a great deal of our GDP is just that, it adds little of true value but creates environmental problems. Even the so called green technologies can generate pollution especially if it is done on the cheap: pollution casts shadow over Chinese solar rare earth metals technology boom Yes carbon is not the only issue, we live on a finite earth with limited resources and sinks, perhaps we also have a responsibility to other species as well and the more we consume the greater stress we place on these habitats.
  16. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    WUWT claims that "during the peak of MWP glaciers were smaller than today" found here does not apply to arctic with very high certainty. Interesting to note, that on the graph above, arctic ice looks on average larger during peak WMP (1000-1300AD) rather than for LIA (1550-1850AD), although probably not statistically signifficant. Still, from that observation with counter-intuitive outcome, we can say that both MWP and LIA were local events while arctic ice could have enjoyed different conditions.
  17. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    The BEST confirmations, Climategate 2.0 looking like a squib, and now yet another bloody Hockey Stick! Not looking to be such a festive season for some, is it? ;-)
  18. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    The "Ice Hockey Stick." Startling stuff but are we truly surprised?
  19. The Debunking Handbook Part 4: The Worldview Backfire Effect
    Shibui, 'skeptics' seem to be able to believe just about any nonsensical thing... so sure, I suppose they could see the hockey stick as 'confirmation bias'. It just wouldn't make any sense given that it has been replicated by numerous studies, analyzed and confirmed by the NAS, and even matched by a few 'skeptic' analyses that set out to disprove it. All of which demonstrates the very opposite of confirmation bias, but that isn't going to stop 'skeptics' believing otherwise.
  20. Climategate 2.0: Denialists Serve Up Two-Year-Old Turkey
    Tom Curtis @ 12 - that brings back memories. Is that now a "skeptic" training video?
  21. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    Yes perhaps we should stick closer to the topic. Adelady. Yes there are other factors affecting population growth. In India the low proportion of females to males born is yet another, which will of course reduce population growth. However, it is notable that all of the methods if overdone could lead to social or economic instability in later years.
  22. The Debunking Handbook Part 4: The Worldview Backfire Effect
    Don't John or Stephan feel that the Hockey Stick could be seen by sceptics as an example of Confirmation Bias?
  23. Climate sensitivity is low
    Eric (skeptic) @245, the rapidity with which a system adjusts to a new equilibrium depends not just on thermal inertia, but also on the magnitude of the disequilibrium. With the enhanced greenhouse effect, the disequilibrium is small, being approximately 1 W/m^2. This is because of both the small initial perturbation and the fact that the full effects of positive feedbacks are not felt until the system approaches the equilibrium temperature. In contrast, in the model analyzed by Lacis et al, the initial perturbation is around 30 W/m^2. Consequently the system adjusts towards equilibrium much faster because of the much larger disequilibrium. Even so, as skywatcher @246 points out, the system has still not reached equilibrium after 50 years. Further, Lacis et al state that they use the Q-flux ocean model with a 250 meter mixed layer depth. Had they used a model with deep diffusion, time to equilibrium would have been significantly extended (by a few centuries, I suspect), but the early changes of the system would have been unaffected. It just would have taken longer to close the last 0.1 W/m^2 of disequilibrium.
  24. Climate sensitivity is low
    Depends what you call equilibrium Eric - the temperature units on the Lacis diagram are pretty large, and it clearly hasn't reached perfect equilibrium even after >50 years. Why you suggest it supports a 10 year equilibrium mystifies me. From the diagram the change has reduced to being relatively slight after ~25 years, but equatorial regions are still cooling after 50 years.
  25. Newcomers, Start Here
    Eric (skeptic) @151, no it means it is a very weak positive feedback. By reducing the difference between polar and tropical temperatures it makes the escape of energy from Earth less efficient. Because the energy escape is less efficient, the global means surface temperature must be higher for the same amount of energy to escape. However, this effect is so small (for the temperature changes involved) that it is extremely dubious that it could be detected against background noise in the coming century.
  26. Newcomers, Start Here
    No, it's a positive feedback (less uneven -> less radiation -> more warming)
  27. Newcomers, Start Here
    Tom, you said "Bodies with very uneven temperatures radiate heat far more efficiently than bodies with very even temperatures." Does that mean that polar amplification (makes temperatures less uneven) is a negative feedback?
  28. Climate sensitivity is low
    A quote from the Climate-time-lag.html article: "How long does the climate take to return to equilibrium? The lag is a function of climate sensitivity. The more sensitive climate is, the longer the lag. Hansen 2005 estimates the climate lag time is between 25 to 50 years." While reading through Lacis et al regarding CO2 as a control knob, I noticed this diagram

    Taking less than 10 years to cool to equilibrium suggests a short lag. That is for full removal of CO2, etc and I don't know if the time constant would be different for a change in CO2. But if the lag time is much shorter than the 25 to 50 years suggested above, then climate sensitivity is also lower than estimated by Hansen.

  29. Newcomers, Start Here
    Eric (skeptic) @146, yes, imthedragon's point @141 is correct, if easily misinterpreted. In the absence of an atmosphere and ocean to both retain heat due to their heat capacity, and to spread heat around due to the motion of winds and currents carrying heat from the tropics to the poles (and to a much lesser extent, from day side to night side, the Earth would suffer similar diurnal temperature variation to that encountered on the moon, ie, between -157 degrees C and 100 degrees C. Instead of that 257 degree C range, we have diurnal temperature ranges of between 5 and 30 degrees C (approximately), and that is almost entirely due to the capacity of the atmosphere and ocean to absorb and retain heat. What is more, that capacity also warms the Earth. Bodies with very uneven temperatures radiate heat far more efficiently than bodies with very even temperatures. For example, even though the effective temperature of the moon, ie, the temperature it would need to be to reradiate the energy absorbed from the sun to space if it was all one temperature, is around 380 degrees C, its blackbody temperature is actually 270 degrees C. The difference is due to the very uneven temperatures on the moon. However, this has nothing to do with the 33 degree C difference between Earth's effective temperature and its mean surface temperature. If the Earth was of uniform temperature with no greenhouse effect, its surface temperature would be 255 degrees K. As the Earth's temperature is not entirely even, it would actually be slightly lower than that, a fact often ignored for simplicity. But without the greenhouse effect, the surface temperature could not be raised above the effective temperature, let alone by the 33 plus degrees that it has been raised. So, yes, the atmosphere apart from the greenhouse effect makes the Earth's surface temperature stable. And yes, the greenhouse effect does nudge the temperature higher. But the 33 degree K (12%) nudge is more than just a bit, and indeed is absolutely crucial to the possibility of life on Earth.
  30. The Debunking Handbook Part 4: The Worldview Backfire Effect
    Steve, I wouldn't put Myers approach to humiliation on the same footing as your 'concern trolls'. I'm not fond of humiliation as a teaching, tutorial or discussion technique, but I know it has many adherents and a long, not-so-glorious history in universities. It's an extension of not suffering fools gladly. Probably marginally useful in training where people are looking to enter professions (in medicine or the military for instance) where clear thinking and rapid judgments can be crucial. I see it as a form of intellectual bullying. Mainly because it tends to become an habitual, charmless style rather than an occasional startling wake-up call. It's only saving grace is that it's honest. The same cannot be said for the 'concern trolls'. Where I see such interventions in discussions, I'm prepared to bet my wardrobe that it's the thin end of a wedge which generally finishes up going in a very unpretty direction.
  31. Newcomers, Start Here
    I think I can answer one of my questions. Pressure broadening in wikipedia is "Impact pressure broadening: The collision of other particles with the emitting particle interrupts the emission process, and by shortening the characteristic time for the process, increases the uncertainty in the energy emitted (as occurs in natural broadening)[3]. The duration of the collision is much shorter than the lifetime of the emission process. This effect depends on both the density and the temperature of the gas." Apparently the heating of the rest of atmosphere by GHGs is one part of pressure broadening. Then the other effect of the rest of the atmosphere is stability from thermal inertia. Both imthedragn and I may have been conflating warming and stability.
  32. The Debunking Handbook Part 4: The Worldview Backfire Effect
    Question: Those of us most interested in the science are upset about political attacks on science and personal attacks on scientists. It happens that a lot of those attacks come from members of given political parties and people with strong political leanings, so a lot of us might identify those parties and leanings as being our enemies. Does this simple identification hurt our chances? Scientists may say, "The world is very likely X and it is very unlikely Y." Then someone jumps in from Political Group A and generalizes on the basis of their own conservation bias, "Yeah, those stupid Political Group B people are all idiots and deny logic and science." Are these people hindering progress by increasing the defensiveness with which anyone who identifies with Political Group B will approach the topic? Should we be trying to censor such supporters of science? Should we censor ourselves when identifying groups who resist the finding that "The world is likely X" and inhibit the dissemination of that finding? To make this 'real' in the context of internet discussions, are the 'concern trolls' correct about tone? Is PZ Myers wrong about the value of humiliation?
  33. Newcomers, Start Here
    Thanks skywatcher, I read the paper, but it merely repeats Tom's explanation about pressure broadening (as shown in Tom's diagram above). Is the lapse rate responsible for the 33C GH effect? If so, are changes lapse rate caused by uneven pressure broadening of increased CO2 (with more broadening at the bottom)? Seems like a valid but only partial explanation. What about heat transferred from CO2 to O2 and N2? I do not believe that can be ignored for both stability and warmth.
  34. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    Back to the issue of economic growth influencing CO2 production, a headline in our local business section says "Oilsands output could triple by 2035", citing a report by the National Energy Board (Canada). Included in the article was a comment from the Pembina Institute that the government had to address mounting environmental challenges if Canada was to reach its 'energy potential'. So far it seems that economic growth is the main consideration.
  35. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    MA Rodger#19: "Hansen & Sato 2004 see the wobbly soak-up rate as important enough to spend one page of a six page paper discussing it." Not so much. Here's H&S' main point on that question: Year-to-year fluctuations of atmospheric CO2 growth must reflect fluctuations of the land and ocean sinks for CO2 and the biomass-burning source. Most of the rest is about other GHGs. "40% is a more usual number" Is it? Again H & S: Fig. 5A shows the CO2‘‘airborne fraction,’’ the ratio of the annual increase in atmospheric CO2 to annual fossil fuel CO2 emissions. Despite large year-to-year fluctuations, the airborne fraction has been remarkably constant at ~60% of emissions during the post World War II period Nor is there any mention of ENSO or either NinX in this paper. Again, I'm not seeing the point of this wobblometry.
  36. Newcomers, Start Here
    Eric, on temperature stability, I'm not sure what your point is. Have you read the Lacis et al paper DB linked to inline at #141? The remaining atmosphere without GHGs can provide a stable temperature ... if you like your temperature to be stable at -21C! Given the lack of water vapour in that atmosphere, I suspect the diurnal range would be pretty brutal round the mean figures too, though cloud cover would tend to moderate it.
  37. The Debunking Handbook Part 4: The Worldview Backfire Effect
    "Another way in which information can be made more acceptable is by “framing” it in a way that is less threatening to a person’s worldview. For example, Republicans are far more likely to accept an otherwise identical charge as a “carbon offset” than as a “tax”, whereas the wording has little effect on Democrats or Independents—because their values are not challenged by the word “tax”.6" Somebody should really forward a copy of this to the Labor strategists that allowed the "carbon tax" to become the commonly accepted way of referring to the policy.
  38. Newcomers, Start Here
    Tom, my understanding is that the CO2 more or less immediately transfers energy from outgoing IR to the rest of the atmosphere. Wouldn't that heating of N2 and the O2 raise the temperature of the atmosphere from bottom to top (more at the bottom) and thus explain the higher lapse rate? Another way to look at it is that the overall mass of the atmosphere dictates the heat capacity but additional CO2 raises it slightly. Thus I think that imthedragn's point about temperature stability (141) is valid.
  39. Climategate 2.0: Denialists Serve Up Two-Year-Old Turkey
    The bottom line: Hacked emails are a sideshow and cannot take away from what many business leaders already know and what the IPCC’s extreme weather report confirms. Climate change is real and we’d better buckle our seat belts for more costly extreme weather if we carry on with business as usual. Source: “IPCC Report Confirms What Businesses Already Know: Extreme Weather & Climate Change Has Economic Impacts” by Mindy Luber, President of CERES, Forbes, Nov 23, 2011 Click here to access this article.
  40. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    MA Rodger - sorry to butt in here, but I'm just joining in near the end of this to-and-fro. You are aware that ENSO affects atmospheric CO2 because of the extra rain that falls over land during La Nina stimulates vigorous plant growth, and cooling of sea surface temperatures? Conversely El Nino warms the sea surface (particularly the equatorial Pacific) which increases CO2 outgassing from the ocean, and the marked drying of the tropical basins diminishes plant growth, and therefore they too give up CO2 to the atmosphere. Volcanic eruptions tend to ramp up CO2 uptake by land-based plants because the diffraction of sunlight enables light to better penetrate the forest canopy. If none of this has anything to do with what you guys are debating, please disregard.
  41. Newcomers, Start Here
    Sphaerica, with respect, I believe your explanation @143 is incorrect. Placing imthedragon's question into context, the Earth's atmosphere contains just 8% of the CO2 contained by Mars'atmosphere. Further, CO2 provides approximately 20-25% of the greenhouse effect on Earth, or about 7 degrees C of warming. If the Earth's CO2 was doubled 3.5 times it would equal Mars' CO2, so on a simplistic view, Mars' greenhouse effect should provide about be 11 degrees warming. That is approximately double the warming it actually provides. A major reason for the shorfall is the lack of pressure broadening. Increased pressure widens the absorption band at the expense of reduced probability of absorption in the central peak. (From Science of Doom) Because in the central peak the atmosphere of both Mars and Earth have an optical thickness greater than 1, the effect of reducing pressure is to increase the altitude of effective emission from CO2 to space. However, it also greatly reduces the bandwidth of that emission, thereby allowing far more heat to escape directly to space from the surface, thereby greatly reducing the greenhouse effect. Mars' surface pressure is 4 to 8.7 mb (depending on season), so the effect is far greater than that illustrated in the diagram above. There are two other significant effects reducing the greenhouse effect on Mars. The first is that the adiabatic lapse rate on Mars (4.5 degrees C per km) is less than half of that on Earth, and significantly less than the environmental lapse rate of approx 6.5 degrees C/km. By itself, this factor would reduce the strength of the greenhouse effect on Mars by about 30%. The second is simply the other gases in the atmosphere. Given a layer of CO2 sufficiently thick to absorb all IR light in its absorption band, if we add another gas that does not absorb IR sufficient to double the atmospheric pressure, the thickness of that layer of CO2 increases. In doing so, the effective altitude of radiation of that CO2 also increases. The strength of the greenhouse effect is most simply calculated by assuming that the temperature at the effective altitude of radiation to space equals the equilibrium temperature of the planet (ie, that temperature which will result in outgoing radiation matching incoming radiation), and then deriving the surface temperature by the lapse rate. Increasing the effective altitude of radiation by adding neutral gasses therefore increases the strength of the greenhouse effect. Consequently, the large concentrations of oxygen and nitrogen on Earth increase the strength of the greenhouse effect on Earth relative to Mars, in addition to the other effects. As a final note, while adding neutral gases does increase the strength of the greenhouse effect, they do not have a direct effect on surface temperature (other than by equalizing the distribution of temperatures). In the absence of a greenhouse gas, adding neutral gases would have no ability to raise surface temperatures above the equilibrium temperature as greenhouse gases do.
    Moderator Response: I suggest adding an Argument: "Why is Mars so cold when it has so much more CO2?" Include not just these reasons, but also an explanation that (and why) the amount of energy from the Sun reaching Mars is so much smaller than that reaching Earth. And give it a link to the Mars is Warming argument.
  42. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    @18 The links have picked up extranious characters. They are in order:- http://www.esrl.noaa.gov/psd/enso/mei/table.html http://cdiac.ornl.gov/trends/emis/meth_reg.html
    Moderator Response: (Rob P) Had to excise your last link, it was messing with the page layout.
  43. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    Muoncounter @17 Hansen & Sato 2004 see the wobbly soak-up rate as important enough to spend one page of a six page paper discussing it. It is as you say but an oscillation on a rising trend but big enough to reduce annual increases by 70% in consecutive years. The causal link – high MEI will restrict ocean absorption of CO2, low MEI will assist it setting the CO2 wobble in motion. (One comment – I was surprised to see the 55% figure for CO2 remaining in the atmosphere on your second graph @14. 40% is a more usual number. I linked back to the graph's origin & CO2 data source & saw two problems. The USEIA CO2 data is a bit low but more worrying, the emissions for land use change appear not to be included in the analysis.)
  44. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    Sphaerica @16 You're asking a bit too much here. The lag (always present) is variable in length and perhaps could be due to the season the El Nino/La Nina occur in. Also the ampitude. Or whatever. That use of an index like MEI comes so close to the CO2 rises with only a starightforward linear re-scaling I fine pretty impressive. And getting a better fit would require a step into the modelling arena, a major piece of work. The “2002 on” section – I wonder that if the next El Nino sees CO2 rises passing well above 3ppm pa, those wobbles wouldn't then look so odd. Your requested 'third line' will require a mix of annual data & monthly data so this is a little more of a task than something done over a cup of tea. And I do wonder what would be gained by plotting CO2 emissions as a separate line. If this does gain a place on my to-do list, I would see more to be gained by subtracting the emissions increase to leave the wobble without the trend. (Of course, it doesn't have to be me that creates the graph when the data is available to all.) MEI data monthly CO2 data CO2 emissions – FF & cement CO2 emissions – land use
    Moderator Response: [Sph] Links fixed. When you post links, try not to use "curly" (“curly” instead of "straight") quotes (or to copy from Word, which tends to automatically give you curly quotes). They aren't the same (to HTML) as straight quotes, and hence the problems (the "extraneous characters" were the curly quotes themselves).
  45. Bert from Eltham at 11:38 AM on 24 November 2011
    Pielke Sr. Misinforms High School Students
    I wonder if Pielke would think that it would be quite acceptable for me to urinate and defecate in my or any other street. Or maybe his street or front yard. Could I just throw my rubbish anywhere I liked? Say out in the same street. Surely as I am only some miniscule proportion of any large group this would not matter? There is no linkage proved with my waste and any disease or annoyance. So if we all did this and put billions of tonnes of this waste into the environment it has absolutely no harmful effect! My body waste and rubbish are very nutritious foods for all sorts of living things such as plants and bacteria and will neatly add to productive food for all! In the middle ages people used to throw their rubbish into the street and waste ran down the gutters. It did them no harm in fact they flourished along with rats and other benign native animals. They even grew grapes in Scotland! We just do not need sanitation or clean water as it costs far too much. Anyway nature or providence will take care of it. There is no evidence that all this expenditure will make an iota of difference! All these people worried about 'pollution' are just anally retentive. They have a secret agenda for world domination by regulating our lack of anal retention. Bert
  46. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    MA Rodger, I'm not seeing the point of this wobblometry. Hansen and Sato's 2004 analysis was reproduced here by D. Kelly O'Day. If you are suggesting there's some sort of causal relationship between MEI and deltaCO2, what is it and why does it work? And why would that be important, as it is little more than an oscillation on a rising trend?
  47. Climategate 2.0: Denialists Serve Up Two-Year-Old Turkey
    lurgee -- "Thus far, the most 'exploitable' line seem to be Phil Jones's comment about the IPCC being above national FOI requests, which seems a reasonable enough statement when referring to an international body" I'm sure that's covered in the first set of emails and jumped on by denialists last time (Caspar Amman, IPCC?), but probably just an email that wasn't cherrypicked for the first release. Zombiegate/Sloppy-seconds-gate/Whatevergate. Same crap, different conference.
  48. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    MA Rodger, What about 2002 on? What about amplitude, as well as an apparent "lag" in some cases but not others. Your eyecrometer seems to be malfunctioning. You are seeing strong correlation and stopping your thought process dead because, in your mind, it's "close enough." Again, why only include those two variables on your graph? Add emissions, then you can make your case more clearly and completely.
  49. Economic Growth and Climate Change Part 1 - Factors Influencing CO2 Emissions
    Sphaerica @14 My apologies but I'm at a loss what you mean by "a lot of major disconnects." This leads me to wonder what you are defining as "short-term". The CO2 increase trace is characterised by a series of wobbles superimposed onto a rising trend of increasing slope. With the exception of the volcano years (63, 82 &91) the MEI matches the CO2 wobble for wobble with perhaps the exception of 2005-8. If the wobbles are the short-term features, surely ENSO represented by MEI is "the major short term factor." That's where I'm coming from. Until I can grasp where you're coming from, thoughts of "a third line" (which will require the use of annual data on a month graph) would be premature.
  50. Newcomers, Start Here
    141, imthedragon,
    So it is really the atmosphere and not greenhouse gasses that provides the stability of the temperature...
    No. You are very grossly understating the role of greenhouse gases. As you already pointed out H2O is a very strong greenhouse gas and, as both skywatcher and I have explained, it dominates near the surface. So where do temperatures vary the most on earth, in a desert or in a rainforest? The latter has nice, cool trees to shade you, and yet it is stiflingly, achingly hot during the day and gives you little respite at night, too. The desert has burning sands in the day, but temperatures plummet at night. The difference lies in water vapor, the powerful greenhouse gas, that is pervasive in a tropical rain forest and prevents it from losing heat, but almost totally absent in a desert and so allows the heat to escape the moment the sun goes down.

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