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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 126601 to 126650:

  1. An overview of Antarctic ice trends
    Very good post. That´s something I occasionally mixed up too. As usual, with the relevant references. Thanks John.
  2. An overview of Antarctic ice trends
    Mizimi, I talked about mass balance not precipitations or whatever. As for albedo, given that sea ice grows during winter when there's almost no sun, I doubt it will have any significant effect.
  3. An overview of Antarctic ice trends
    Riccardo: but the extent of sea ice affects precipitation in the interior, so I do not see that you can realistically separate the two. In addition, sea ice growth affects albedo whereas land ice decline does not ( at least until bedrock is uncovered).
  4. High CO2 in the past, Part 2
    re #12 There's a huge amount that can be pointed out in relation to your comment HumanityRules. Here's a few relevant points: (i)The data in Figure 2 above is an extremely broad scale analysis from a model of atmospheric CO2 based on estimated weathering/continental positions etc with a 10 million year resolution, compared with a massively smoothed proxy record. The aim is to demonstrate at extremely low resolution, the broad change in radiative forcing resulting from a combination of progressively increasing solar constant and very broad range variations in atmospheric CO2. (ii) A realistic analysis of the relationship between atmospheric CO2 levels and climate can only be made by considering discrete proxy temperature and proxy CO2 data, and causal relationships can only be assessed where these temperature and CO2 proxies are contemporaneous. If this is done [see review by Royer (2005) – click on link in John Cook’s summary above ; this should actually be Royer (2006)!), there is a broad correspondence on a much tighter time resolution relevant to greenhouse gas-climate coupling. (iii) This analysis has been extended in recent years, and indicates a number of further examples where contemporaneous temperature proxies and CO2 proxies have been analyzed. In general where CO2 levels are high, temperature proxies are high, and onset of cold/glacial conditions are associated with reduced atmospheric CO2. I’ve dumped a number of more recent papers just below [*]. There is now also a wealth of papers defining the onset of glacial conditions in the Miocene associated with the drop of atmospheric CO2 levels below thresholds that allow build up of polar continental ice sheets. (iv) focussing on the Carboniferous and your specific comment. While it was thought previously that there was a single Carboniferous glaciations/cold period associated with a long slow and rather massive pull down of atmospheric CO2 into plants (and their deposition and eventual burial under conditions where oxidative decay was suppressed), this period seems to be separated into an early glacial period and a later cold period, separated by a warmer spell. Unfortunately there is only one atmospheric CO2 proxy contemporaneous with this warmer spell in between the two cold periods, but this proxy indicates a CO2 level around 1500 ppm. So it seems not only very likely that the cold Carboniferous periods were the result of massive pull down and sequestration of CO2 from the atmosphere, but that the intermediate “non-cold” interval was associated with a period of raised CO2. This is described in Royer’s review (click on John Cook’s link above and see section 3.4). [*] Since Royer’s compilation of proxy CO2 data and Phanerozoic estimates of earth temperature regimes, there has been a large amount of new data which supports a broad coupling of earth temperature and atmospheric CO2 levels: R.E. Came, J.M. Eiler, J. Veizer et al (2007) "Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era" Nature 449, 198-202 W. M. Kurschner et al (2008) “The impact of Miocene atmospheric carbon dioxide fluctuations on climate and the evolution of the terrestrial ecosystem” Proc. Natl. Acad. Sci. USA 105, 499-453. D. L. Royer (2008) “Linkages between CO2, climate, and evolution in deep time” Proc. Natl Acad. Sci. USA 105, 407-408 Zachos JC (2008) “An early Cenozoic perspective on greenhouse warming and carbon-cycle dynamics” Nature 451, 279-283. Doney SC et al (2007) “Carbon and climate system coupling on timescales from the Precambrian to the Anthropocene” Ann. Rev. Environ. Resources 32, 31-66. Horton DE et al (2007) “Orbital and CO2 forcing of late Paleozoic continental ice sheets” Geophys. Res. Lett. L19708 (Oct. 11 2007). B. J. Fletcher et al. (2008) “Atmospheric carbon dioxide linked with Mesozoic and early Cenozoic climate change” Nature Geoscience 1, 43-48. etc. etc.
  5. An overview of Antarctic ice trends
    OFF TOPIC (but only just) Interesting paper in GRL about artic ice "Extraordinary September Arctic sea ice reductions and their relationships with storm behavior over 1979–2008" Interesting because it looks at different mechanisms for ice loss in the artic than temperature. In short they found a relationship between artic ice minimum and cyclone activity (strength). Of course this only shows a relationship in doesn't give cause or effect. Although the authors, as is their right, seculate on this. The simple idea that hotter planet=less artic ice maybe too simple to explain reality. An inconvinient truth?
    Response: Thanks for the link. I've updated the link to a publically accessible version. Simmonds 2009 is an interesting paper - it basically confirms the results of Gascard 2008 who found cyclonic conditions in 2007 transported sea ice out of the Arctic. It also repeats the conclusion of Nghiem 2007 who found that similar cyclonic conditions have occured before but that with the long term trend of thinning Arctic sea ice, the sea ice is much more vulnerable to getting broken up and transported out of the Arctic. I go into more detail elsewhere explaining Arctic sea icemelt - I suggest you post any on-topic comments there.
  6. High CO2 in the past, Part 2
    I wonder about the relevance of this sort of analysis based on that sort of timescale. In the first paragraph you mention the last ice age was 11,000years ago. I don't know what that means in terms of mean global temp or change in radiative forcing but I'm going to speculate a noticable shift in terms on the vertical axis of the graph above. And I think we would agree some (I'd say most) of that shift has been due to natural causes. So the end of the carboniferous/start of the permian represents maybe +10million years of low radiative forcing, two periods of glaciation but obviously intermediate periods of non-glaciation. How did the earth come out of those glaciation periods when the radiative forcing remains low? Surely there is some lack of detail in these numbers particularly as you go further back in time. The relative smooth movement of the data early on and the more up/down in recent times suggests that. On a superficial level it tells a nice story but I'm not sure it really details the movement of earths climate over that period.
  7. It's freaking cold!
    On this issue, "climate change" is more apt than "global warming". And "climate is weather averaged over time" is more explicit than "weather is not climate." The 'weather' skeptic's defense will be: "They do it too. If there's a warm spell, the believers will say its due to global warming." After years of temperature increases, it is harder for believers to restrain such statements. But they should be restrained. Weather IS variable. In addition, maybe policymakers should just whisper among themselves, about a current event occurring more frequently in a global warming future...to avoid the shortening misquote, that GW caused the event??? WEATHER'S ONE MONTH EFFECT... ...even averaged over a month, local weather anomalies (dynamical fluctuations, more-or-less independent of forced long-term climate change) are much larger than the global mean temperature change of recent decades. Weather fluctuations or 'noise' have a noticeable effect even on monthly-mean global-mean temperature, especially in Northern Hemisphere winter. Weather has little effect on global-mean temperature averaged over several months or more. The primary cause of variations on time scales from a few months to a few years is ocean dynamics, especially the Southern Oscillation (El Nino-La Nina cycle)... Columbia.edu COLD EXTREMES HAVE WARMED MORE... In the last 50 years for the land areas sampled, there has been a significant decrease in the annual occurrence of cold nights and a significant increase in the annual occurrence of warm nights...Decreases in the annual occurrence of cold days and increases in hot days, while widespread, are generally less marked. The distribution of minimum and maximum temperatures have not only shifted to higher values, consistent with overall warming, but the cold extremes have warmed more than the warm extremes over the last 50 years. IPCC AR4 WGI FAQ 3.3 REGIONAL EXCEPTIONALISM FOR GW FUTURE COLD SPELLS..? It is also likely that a warmer future climate would have fewer frost days (i.e., nights where the temperature dips below freezing)...There is likely to be a decline in the frequency of cold air outbreaks (i.e., periods of extreme cold lasting from several days to over a week) in (Northern Hemisphere) winter in most areas. Exceptions could occur in areas with the smallest reductions of extreme cold in western North America, the North Atlantic and southern Europe and Asia due to atmospheric circulation changes. IPCC AR4 WGI FAQ 10.1
  8. Antarctica is gaining ice
    Sure chris, I did not mean to suggest that ice loss is _not_ happening, just to point out that we should be careful. The last thing the public debate needs, is accusations of "alarmism" with some degree of justification to them. Which could easily happen if this ice mass change, for instance, turns out to be a quasi-periodic phenomenon somewhat akin to the PDO. Another thing I am wondering about, is the net effect of the situation underlying the (rather slow) increase in sea ice. Albedo should be increasing a little bit, but what about the heat loss from sea? Could the extra warming of the sea and the increasing sea ice be two aspects of the same circulatory phenomenon? Maybe a stupid question, I'm not very much into this :-)
  9. CO2 is not the only driver of climate
    Gord, re 216 it is not the temperature of the atmosphere that inhibits the cooling of the surface, but its chemical composition. As to why this should be impeded for the simple reason that some IR is absorbed before it can be emitted to space. I think that amount of energy emitted to space must eventually balance with the amount of energy received from space. Your heat sink example misses the relevant issues of the GH effect namely the lapse rate and the fact that some IR energy is absorbed prior to emission. No one is arguing that energy in shouldn't equal energy out. THe point is that one can potentially have many different operating temperatures for *the surface of the microprocessor* depending on how efficiently it can radiate its heat energy. If the microprocessor is less efficient at radiating its heat energy(perhaps because it is wrapped in insulation), then its temperature goes up, but not because the temperature of the heat sink warmed it, but because it could not radiate *its own heat* as effectively. Just so you have a relatively complete picture of what happens in the atmosphere per my POV- a GH gas free atmosphere would dissipate heat directly from its surface, giving it an average surface temperature of ~-18C. Now, when we add more GH gases to the atmosphere, *the surface cannot radiate that heat as effectively* so in order to balance the incoming and outgoing energy higher levels of the atmosphere must radiate more energy than they would OTW. The only way the higher levels of the atmosphere can do this is by raising their temperature. However, given that the Earth has a lapse rate, *the only way for the temperature of the atmosphere to go up is for the temperature of the surface to go up higher than that of the atmosphere*. This explanation has nothing to do with the temperature of the atmosphere increasing the temperature of the surface anti-thermodynamically(by heat flowing from cold to warm), as you seem to think. All heat energy comes from the sun, however, the physical properties of the atmosphere and the need to balance the incoming and outgoing energy combine to raise the surface temperature by changing *how heat moves from hot to cold*. Cheers, :)
  10. An overview of Antarctic ice trends
    Mizimi, this post was actually devoted to clarify the difference between sea and land ice. Mass balance should be done for land ice, being sea ice seasonal and formed by compleately different processes.
  11. An overview of Antarctic ice trends
    According to the graph, antartic sea ice has grown in area by some 0.7 x 10E12 m2 in 23 years, so I would expect a measurable increase in albedo. Also pertinent is the mass of sea ice. Assuming a mean ice thickness of 62cm this equates to .45 x 10E12 m3 of ice...or 450 Gtonnes...about equal to the land loss from 2002 to 2005. Agreed the rates of growth/loss are not in balance, but would we expect them to be? As sea ice extends, so I would expect less snowfall in the interior and thus less replenishment of land-ice melt. Are there any longer time series for Antartic ice cover?
  12. Antarctica is gaining ice
    yes, agreed SNratio (re #11). However there are longer term measures of Antarctic ice mass loss from altimetry that are consistent with a nett mass loss in Antarctica (which is still pretty small in relation to the vast amounts of Antarctic ice) [*]. We should also note that the corrections applied by Bevis et al. (2009) suggest that a bias in ice mass loss from GRACE measurements amounts to ~33 Gt/yr [**]. This is a significant, but small, proportion of the total Antarctic ice loss determined by GRACE (see figures in John Cook's summary above): [*] E. Rignot et al. (2008) Recent Antarctic ice mass loss from radar interferometry and regional climate modelling Nature Geoscience 1, 106 - 110 (2008) [**]Bevis et al. (2009) para [19]; page 9:
    We can estimate the potential magnitude of the ice mass biases by noting that if the average velocity prediction bias of ~5 mm/yr evident in Figure 5 is developed over ~2 × 10^6 km2, an area somewhat smaller than that of West Antarctica, this would cause an apparent but spurious ice loss of ~33 Gt yr-1, which is a significant fraction of all published ice mass rates derived from GRACE [Velicogna and Wahr, 2006; Chen et al., 2006; Ramillien et al., 2006; Sasgen et al., 2007a]. However, it is not possible to arrive at an accurate numerical estimate of the impact of our geodetic measurements on GRACE ice mass change solutions without finding a reliable means to interpolate between our point measurements of vertical crustal velocity.
    The authors (Bevis et al, 2009) also point out that GRACE should make reliable estimates of any further enhanced acceleration in ice mass loss (or sudden jumps in ice mass loss), since the post-glacial rebound (that has to be corrected for in mass change estimations) doesn't vary much on the interannual timescale.
  13. An overview of Antarctic ice trends
    I'd also like to add this papers regarding sea ice in Antarctica: 1) Stratospheric ozone: Shindell & Schmidt 2004 2) Freshening (and stratification) of surface waters: Jacobs et al 2002 3) Snow turned into ice: Cavalieri et al 1997, where they say: "The observed hemispheric asymmetry in these trends is consistent with a modeled response to a carbon dioxide-induced climate warming". Markus & Cavalieri 2006 (pdf available here
  14. An overview of Antarctic ice trends
    Regarging sea ice increase in Antarctica, there's also a good summary in this NASA note. They also mention that flooded sea ice turns snow to ice.
  15. An overview of Antarctic ice trends
    Clearly these disparate phenomena (land versus sea ice) are better explained by the Sun than by greenhouse gases because, uh, actually no, it's all because of ocean cycles and stuff and, erm, or really this is all just a case of unreliable data and analyses -- the scientists are just trying to get more funding by producing confusing results! More seriously (but perhaps still trivially), has this measurably increased the albedo of Antarctica and thereby provided any negative feedback at all? Or, more generally, are there important impacts (besides effects on sea ice) of warmer salty water being overlaid by a thicker layer of cold fresher water?
  16. CO2 is not the only driver of climate
    Gord, for a Stefan-Boltzman calculation of an atmosphere-free Earth's temperature (i.e., naked exposure of the Earth's surface to the infinite heat sink of outer space), see the web pages by Nolan Atkins that are part of his Lyndon State College course, but only the two sequential web pages here and the next one. Let's first come to understanding only with that case before adding the atmosphere. (So please don't reply with calculations about what happens with an atmosphere.) Do you agree with the calculations, results, and interpretations on that short sequence of two web pages?
  17. CO2 is not the only driver of climate
    Gord, your example is missing a piece from its initial condition. At the very beginning, before you add the atmosphere as a heat sink, you must have outer space as a heat sink.
  18. CO2 is not the only driver of climate
    Shawnhet - re:your post 215 Yes, it has been covered before....many times. Why would you even think that the colder atmosphere would somehow cause the Earth's surface to not cool as quickly? How can a cooler atmosphere impede the Earth's radiation when the Earth provides the energy to heat the colder atmosphere? The Sun HEATED the Earth, and the Earth's radiation HEATED the the atmosphere and all the Radiation is then transferred to cold space. Look, let's examine a common device known as a Heat Sink. It is used to cool electronic devices like the Microprocessor in your computer. The electrical power (Sun) heats the Microprocessor (Earth) just like the Sun heats the Earth. Lets say the Microprocessor operates with (and has to dissipate) 10 watts of power (Sun) and it's surface area is 0.01 m^2. The Electromagnetic Field radiated by the Microprocessor (Earth) is 10 Watts/0.01 m^2 = 1000 w/m^2. The surface temp of the Microprocessor can be calculated by the Stefan - Boltzmann Law. Power/Area = Boltzmann's Constant X Temp^4 Temp^4 = 1000 w/m^2 / 5.67 X 10^-8 = 1.76 X 10^10 Temp = 364 K or 91 deg C We want the Microprocessor to drop in temp by placing a Heat Sink on it that will only be heated to 25 deg C or 298 K A Heat Sink (atmosphere) is initially at room temperature (20 deg C) and is placed on the Microprocessor (Earth) with a slight air gap so heat transfer by radiation is dominant. The Heat Sink has to have a larger surface area. Power/Area = 5.67 X 10^-8 X 298^4 = 447 w/m^2 Area = 10 Watts/447 = 0.022 m^2 The Microprocessor and the Heat Sink will now operate at a temperature of 25 deg C. So what happened here? The Electrical power provided is 10 Watts (the Sun). The Microprocessor (Earth) that was operating at 91 deg C transferred heat energy to the cooler Heat Sink (atmosphere)(initially at 20 deg C) raising it's temp to 25 deg C. The Microprocessor (Earth) and Heat Sink (atmosphere) stabilize at a temperature of 25 deg C and 10 watts of power is still dissipated to the suroundings (analagous to cold space). Did the Heat Sink (atmosphere)impede the Microprocessor (Earth) radiation?....Of course NOT! Did the Heat Sink (atmosphere) cause the Microprocessor (Earth) to "not cool as quickly" and increase in temperature?....Of course NOT!...EXACTLY THE OPPOSITE OCCURED! ----------------------- The only difference between this example and the SUN - EARTH - ATMOSPHERE - COLD SPACE system is that the Heat Sink was assumed to have an emissivity of 1. If the Heat Sink (atmosphere) had an emissivity less than 1 it would not have absorbed all the heat energy of the Microprocessor (Earth) and would have had a temp lower than 25 deg C....just like the real atmosphere is colder than the Earth. ------------------------- This may be one of my last posts on this forum. Too much repetion is required explaining the same Physics over and over again and answering the same questions over and over. And, there is FAR too much censorship!
  19. Extreme weather isn't caused by global warming
    By mid-century, annual average river runoff and water availibility are projected to increase by 10-40% at high latitudes and in some wet tropical areas, and decrease by 10-30% over some dry regions at mid-latitudes and in the dry tropics; some of which are presently water stressed areas... Drought affected areas will likely increase in extent. Heavy precipitation events, which are very likely to increase in frequency, will augment flood risk. IPCC AR4 WGII Summary for Policymakers. In a warmer future climate...Models project increased summer dryness and winter wetness in most parts of the northern middle and high latitudes. Summer dryness indicates a greater risk of drought. Along with the risk of drying, there is an increased chance of intense precipitation and flooding due to the greater water-holding capacity of a warmer atmosphere. This has already been observed and is projected to continue because in a warmer world, precipitation tends to be concentrated into more intense events, with longer periods of little precipitation in between. Therefore, intense and heavy downpours would be interspersed with longer relatively dry periods... IPCC AR4 WGI FAQ 10.1 The warmer climate therefore increases the risks of both drought - where it is not raining - and floods - where it is - but at different times and or places. For instance, the summer of 2oo2 in Europe brought widespread floods but was followed a year later in 2003 by record-breaking heat waves and drought. The distribution and timing of floods and drought is most profoundly affected by the cycle of EL Nino events... ...overall trends in precipitation are indicated by the Palmer Drought Severity Index...which is a measure of soil moisture using precipitation and crude estimates of changes in evaporation. (The PDSI graph shown roughly increases below the "0" line until about 1977, after which its all above the line.) IPCC AR4 WGI FAQ 3.2 Drought is easier to measure (than heavy precipitation events) because of its long duration...The Palmer Drought Severity Index calculated from the middle of the 20th century shows a large drying trend over many Northern Hemisphere land areas since the mid-1950's, with widespread drying over much of southern Eurasia, northern Africa, Canada and Alaska...and an opposite trend in eastern North and South America...Decreases in precipitation over land since the 1950s are the likely main cause for the drying trends, although large surface warming during the last two to three decades has also likely contributed to the drying... IPCC AR4 WGI FAQ 3.3
  20. CO2 is not the only driver of climate
    Gord, re #210 (and I apologize if this has already been covered). If the atmosphere can absorb and emit IR radiation won't this imply that the surface will not cool as quickly as it would OTW? If not, why not? Put another way, wouldn't the complete absence of GH gases mean that all the incoming solar radiation would be radiated away from a lower height in the atmosphere(since there would be nothing to impede the radiation). Since Earth has a lapse rate(ie temperature decreases as we rise above the surface), doesn't any absorption of IR radiation in the atmosphere necessitate that the surface must get warmer? If not, why not? Cheers, :)
  21. Antarctica is gaining ice
    It should be noted that the observational period here is quite short, so one should be careful about firm conclusions. And, the precise extent may be somewhat lower than presented: Geodetic measurements of vertical crustal velocity in West Antarctica and the implications for ice mass balance Received 20 May 2009; accepted 28 August 2009; published 13 October 2009. Citation: Bevis, M., et al. (2009), Geodetic measurements of vertical crustal velocity in West Antarctica and the implications for ice mass balance, Geochem. Geophys. Geosyst., 10, Q10005, doi:10.1029/2009GC002642. "We present preliminary geodetic estimates for vertical bedrock velocity at twelve survey GPS stations in the West Antarctic GPS Network, an additional survey station in the northern Antarctic Peninsula, and eleven continuous GPS stations distributed across the continent. The spatial pattern of these velocities is not consistent with any postglacial rebound (PGR) model known to us. Four leading PGR models appear to be overpredicting uplift rates in the Transantarctic Mountains and West Antarctica and underpredicting them in the peninsula north of 65°. This discrepancy cannot be explained in terms of an elastic response to modern ice loss (except, perhaps, in part of the peninsula). Therefore, our initial geodetic results suggest that most GRACE ice mass rate estimates, which are critically dependent on a PGR correction, are systematically biased and are overpredicting ice loss for the continent as a whole."
  22. The albedo effect
    re #17, so Palle's graph in 2004 shows a drop in albedo in 1997. Palle's graph in 2009, doesn't show a drop in albedo in 1997 [see Figure 2 (top) of Palle et al (2009) [*]; the pre-publication manuscript can be read by clicking on John Cook's "Palle 2008" link in the top summary)]. Palle's graph in 2004 shows a large rise in albedo in 2003. Palle's graph in 2009 doesn't show a large rise in albedo in 2003. My conclusion would be that Palle's determination of albedo measures isn't particularly robust (or at least wasn't in 2004), and the suggestion that there was a drop in albedo in 1997 coupled with an insinuation that this might have something to do with the very warm 1998, is flawed. After all if Palle has reinterpreted earler work that suggested a "distinct drop in albedo in 1997", to conclude in later work that there wasn't a "distinct drop in albedo in 1997", I don't see the point of pretending that the data still suggests a drop in albedo in 1997. Or do you have a good reason to reject Palle's own reinterpretation of his earlier work? [*] Palle et al. (2009) Inter-annual variations in Earth's reflectance, 1999-2007 J. Geophys. Res. 114, D00D03
  23. Philippe Chantreau at 16:28 PM on 7 November 2009
    CO2 is not the only driver of climate
    I think Gord is confused. He (or she) is confusing a physical phenomenon with the representation of it. He can apply formulas but lacks a real understanding of the physical phenomena they describe. I don't care whether he is an engineer, student engineer, whatever. He may be more skilled that I at playing with formulas but he does not understand the stuff he keeps on posting in the belief it answers pertinent questions. I am unimpressed. Everyone I could ask abouth this who studies or teaches physics confirmed my understanding of it. NASA confirms it, every single physics link out there confirms it as well if one looks close enough. He is considering one side of a heat transfer in isolation although that side does not exist in isolation of the larger transfer that makes it possible in the first place. The overall exchange of energy between the surface and atmosphere complies with the 2nd law. I believe that I made a number of petinent points in post #149 that were not answered appropriately. Gord keeps on repeating stuff that does not, in fact, support his interpretation. OK so the Sun heats the Earth, which then heats the atmosphere, what happens at night? If there is no such thing as a GH effect, why are the daily temps, nightly temps and average temps not similar to those found on the Moon? What do we have on Earth that prevents our temps to drop near absolute zero at night? Oceans? Why does Antarctica NOT drop near absolute zero during the Austral winter? Why is the surface of Venus warmer than Mercury's and how does Venus maintain nearly identical temperatures on its sunny and shady sides? Makes NO SENSE without a GH effect. Looking back at post # 168, Gord's calculations bring 2 objects in equilibrium both radiating 90W when we started with 90 and 60. Looks strange. We started with a total of 150, the object transferring energy has not cooled and still radiates at 90W, but the other one has warmed and now also radiates at 90W. A total of 180, compared to the 150 we started with. Looks funny. I don't believe Gord knows what he's doing. I have already spent way too much time on this but it appears to me that his calculations on Earth temps are equally mistaken, and what I found in the response to the G&T paper makes a lot more sense. Response to the Gerlich and Tscheuchner paper disputing the existence of GH effect: http://rabett-run-labs.googlegroups.com/web/G%26T2.11.doc?hl=en&gda=GiEkiT8AAAAXmxShcFP2xrtZ1iQa9EYObLHe1BSUDn5EEukXYSRaprw7opP7C43-G-AfaR61VoGccyFKn-rNKC-d1pM_IdV0 If nothing colder can radiate EM radiation, how can I see a glowstick whose surface is much colder than the surface of my eyes? Why is NASA insulating spacecrafts with radiant barriers since, according to Gord, they can not radiate any IR back to the body they insulate? How can the action of cooling a spectrometer CREAT a IR flux going against an immensely larger and warmer body (Earth's surface?). And even if that was the case, why would the IR flux observed increase as altitude decreases and the proximity to the larger warmer body increases? And what emits this IR radiation in the first place? It makes no sense whatsoever.
  24. CO2 is not the only driver of climate
    Upon reviewing some of my previous posts (which I have stored on my computer), I find that they have also been deleted. I no longer have any desire to participate in this forum.
  25. CO2 is not the only driver of climate
    (This is my fourth attempt to get this posted without deletion - now subjected to new censorship) It appears that constant repetition of my posts are still required. Does anybody out there understand what "continuous" means? The Stefan-Boltzmann Law: Power/Area = Boltzmanns Contant X Temp^4 (watts/m^2) The only time there will not be an Electromagnetic Field produced is when T = 0. Clearly, if T is greater than absolute zero an Electromagnetic Field is produced....continuously. The Stefan-Boltzmann Law is A LAW OF SCIENCE. When some people say the EM field is not continuous it is an obvious contradiction of the Stefan-Boltzmann Law. -------------------- I have also repeatedly posted Physics Links that Heat Radiation is heat transfer by Electromagnetic Waves. Heat Radiation is heat transfer by electromagnetic waves. (see my post #203) Heat Flux is the representation of Heat Radiation as a Vector quantity that uses w/m^2 as the Magnitude of this Vector quantity. The w/m^2 is, of course, used in The Stefan-Boltzmann Law. Heat flux (see my post #203) Yet, there are people who continue to say that Heat Radiation and Heat Flux are not representative of Electromagnetic Waves. ----------------------- I have also repeatedly posted Physics Links that describe Interference including links that explain the phenomena very clearly using continuous waves. Interference (wave propagation) (see my Post #152) Cancellation of Light - Bubble example where light is totally cancelled (continuous waves) - Constructive and Destructive Interference as it relates to Diffraction (continuous waves). - more on Constructive and Destructive Interference (continuous waves) (the links are in my post #152) Despite all the evidence (known for hundreds of years) and all the evidence in their daily lives that the interference of continuous EM waves (eg. like Solar light) produces continuous interference patterns, some people still ignore these simple facts. ------------------------ Arguing with people that ignore these obvious facts and produce posts that contradict Laws of Science, is not only Tedious, it is Frustrating. We are in the 21 Century and this Science has been well known and used for over a hundred years. It would actually be funny, if it wasn't so sad. --------------------------- PS: John Cook will be deleting my comments if I copy and paste material from past comments. Presumeably, this will also include the Laws Of Science and Physics Links that I have previously posted. Since Laws of Science and Physics do not change, please do not attempt to re-write these Laws of Science or Physics based on "opnions". My hands are now effectively "tied behind my back" as far as disputing "opinion based re-writes" of these fundamental truths. Opinions are now in control, not the actual Science. Hopefully, John Cook will also delete those constantly repeated questions directed to me that required repetion of my previous posts. If this is not applicable to those people that constantly ask the same repeated questions of me, I will simply respond that the question has already been answered. Oh well, it was fun before the censorship became stiffleing. It would actually be funny, if it wasn't so sad.
  26. CO2 is not the only driver of climate
    Gord, you might want to follow a sort of "lesson for laymen" (skip the first 10 minutes or so) given by Prof. Archer from the University of Chicago on the very basics of the greenhouse effect. Hopefully a full lesson from a climatoligist will clarify the missing concepts.
  27. CO2 is not the only driver of climate
    shawnhet - Re:your post #209 You said... "So, if greenhouse gases keep the Earth's surface from falling below -20C(or whatever number), doesn't the temperature of the surface have to rise above that when the sun is hitting it?" First, you have to get Cause and Effect correct. The Earth is heated by the Sun (the only energy source). The Earth's radiation then heats the atmosphere to -20 deg C. The colder atmosphere does not heat the warmer Earth. The Sun, being the ONLY energy source, HAS to be the cause of the Earth's surface temperature. I have already posted numerous examples of how the Sun can produce the current Earth surface temperature. Don't you recall my posts directly to you on this subject? --------------- You said... "Doesn't the fact that greenhouse gases absorb energy necessitate that the surface temp of the Earth must be greater than it would OTW be?" No, of course not. The Greenhouse Gases only absorb enough IR energy from the Earth to heat up to -20 deg C. A body of -20 deg C cannot Heat a warmer Earth. I have also produced many posts on this before. Did you not see them? ----------------- Please review my previous posts before asking questions that have already been answered. That will save both of us time and needless repetition.
  28. CO2 is not the only driver of climate
    Gord, re: #183 So, if greenhouse gases keep the Earth's surface from falling below -20C(or whatever number), doesn't the temperature of the surface have to rise above that when the sun is hitting it? Doesn't the fact that greenhouse gases absorb energy necessitate that the surface temp of the Earth must be greater than it would OTW be? Cheers, :)
  29. The albedo effect
    17#..sorry should have mentioned it is on page 13.
  30. The albedo effect
    Chris: the original 2004 graph is here: http://science.larc.nasa.gov/ceres/STM/2005-05/loeb_earthshine.pdf which contests the accuracy of earthshine data. Palle's graph shows a distinct drop in albedo in 1997 which was followed by a hot 1998.
  31. The albedo effect
    RSVP, there's no definition of a wavelength range. In general the albedo varies with wavelegth but is usually measured over wide range. As stated in this post, the earthshine measurements cover 0.4-0.7 microns while CERES data cover 0.3-5.0 microns. They both cover the visible spectrum, where the sun radiation mainly is.
  32. The albedo effect
    Question: From the discussions so far, I get the impression that albedo refers to the visible portion of the electromagnetic spectrum, but I didnt see this explained anywhere. Is there a defined band or cutoff frequency?
    Response: Albedo refers to reflected sunlight, which includes UV light, visible light and wavelengths above the visible spectrum. This covers radiation from around 0.3 microns to 1.2 microns. Visible light is part of this spectrum: roughly 0.4 microns to 0.7 microns.
  33. The albedo effect
    Henry Pool, not sure this is what you were looking for, but here you find the annual minimum concentration time serie while here are the monthly values. I'm going to ignore your last complain given the effort we put to point at the relevant physics you probably didn't look at.
  34. The albedo effect
    I thought global warming has been stalling for quite a number of years now, I think the fact the earth has been brightening would be a reasonable explanation for this? It makes sense that it will take a few seasons after the brightening of earth that some noticable cooling will take effect.. Did anyone find a graph plotting ozone concentrations per annum? Surely that must be possible to find that data? I am not the man who claims to be the expert - I am just checking whether the science is there. I think it is not. I still donot where that 1.7 for CO2 came from. I said it is probably based on the assumption that CO2 is the problem . You then promised to show me the calculations how that was arrived at. As far as CO2 is concerned, no one from your site (side) came to me with comprehensible experiments that took the cooling of CO2 into account and that resulted in convincing figures..
    Response: Global warming hasn't stalled - satellite measurements find the planet is still in positive energy imbalance and ocean heat measurements find the planet is still accumulating heat.
  35. Empirical evidence that humans are causing global warming
    Usmar, the conclusion should be that there's no more CO2 in the atmosphere given how much we take out each year. Clearly this is not the case. You should follow the whole carbon cycle, not just one single step. The carbon stored in crops is recycled quickly, it averages to zero. Trees, on the contrary, live and continuosly take out CO2 from the atmosphere for centuries before their carbon is recycled. Not a subtle difference indeed.
  36. The albedo effect
    Henry Pool, following Palle 2008, the albedo increased while the earth was warming, instead. This should make clear that there's not a simple and direct relation between the observed albedo changes and the earth surface temperature trends. As for the future trend, I'm glad that you are "pretty sure" about one thing that scientists working in the field admit they don't know. Definitely you should tell them.
  37. The albedo effect
    Did anyone read the conclusion of Palle et al 2008? "In the common period, earthshine, CERES along with ISCCP-FD data show a trendless albedo. However, preceding CERES, earthshine and ISCCP-FD reflectances show a significant increase before flattening and holding the increase. This implies a reduction in the net sunlight reaching earth...it is important to point out that the physical causes behind these decadal variations in albedo are still unknown, and that we just don't know yet whether we should expect the albedo changes observed during the modern period to persist into the future.." end quote. I am pretty sure that the increase will hold because it is most probably due to a) an increase in CO2 b) an increase in ozone (due to elimination of CFC's) and c)greater shallow water reservoir surface areas due to human activities. These three components in gasform cause most of earth's reflection. You can look this up in your own quoted papers that show the common solar radiation spectrum. (I remember it refused to speak about or admit that CO2 also causes cooling and it seemed deliberately confusing). Obviously as the weather was getting warmer more clouds are formed, which also helps to reflect more sunlight to space. The reflected sunlight is what makes earth cooler. Anyways, does anyone have any figures about ozone and the ozonehole? I have not heard much about it lately, so this may mean that it must be closing and that means less sunlight (the "bulky" part of the spectrum ) is getting through. This is what the report is saying. I have not yet seen a study that assesses the cooling properties of CO2 (when it is hit by sunlight) and compare them with warming properties of CO2 (when it is hit by earth's radiation). My gut feeling tells me that the nett effect will be close to zero. I am not sure what you people are going to do or say in Copenhagen. I am more and more convinced CO2 is not the problem.
  38. High CO2 in the past, Part 2
    Comment 36 here has information relevant to my comment #7. Perhaps it's a preview to the post John says he may eventually do. I look forward to it!
  39. CO2 has been higher in the past
    Re #35: Don't worry Chris, pretty much all of your contributions are appreciated (at least by me) regardless of what baited you into the work. Re #36: Here is an excellent example of a very worthwhile comment that I just about missed. In fact, I was trying to stimulate something similar on another thread in which I noted that "Global Warming is Good" is an argument not often tackled here, and where I suggested that skeptics should ask how fast CO2 concentrations have changed in the past and what was the result. Thanks.
  40. CO2 is not the only driver of climate
    This Zona Land site has great animations of wave interference! The ones of most relevance are Wave Interference 1, Wave Interference 2, and Wave Interference 3, which illustrate waves passing through each other unaffected after they have shared the local space where they superposed. The VRML Interference Worlds looks fun, though I haven't tried it.
  41. CO2 is not the only driver of climate
    Gord, see also the Wikipedia entry on Superposition, the section on Application to Waves.
  42. CO2 is not the only driver of climate
    Gord, the topmost animation on this page shows the passage of waves through their superposition and then unmodified onto their original destinations, as Riccardo explained.
  43. The albedo effect
    Which "original graph" are you talking about Mizimi? Why not link to, or cite, the data you refer to??? If you look at Palle (2008) [published as Palle et al. (2009) J. Geophys. Res. 114, D003D03], the albedo doesn't "show a distinct drop in albedo in 1998". In fact the albedo in 1999 is lower than 1998 (see Figure 2, top). Please clarify. Note that Palle et al. 2006 [*] point out that one can't translate a change in albedo to a forcing in the manner that you suggest (your "0.7 W" comment) without considering the source of the albedo change. If it's due to a cloud response, an increase in albedo doesn't necessarily mean a negative forcing since any increased cloud response also has an element of suppressed radiative dissipation of thermal energy (see post #6 above). In any case if heat is being added to the oceans, then heat is being added to the oceans! Your putative "happens to balance" obviously isn't balancing at all. [*] E. Pallé et al (2006) Can Earth's Albedo and Surface Temperatures Increase Together? Eos Trans. AGU, 87(4), doi:10.1029/2006EO040002
  44. Are humans too insignificant to affect global climate?
    #1 David Horton:
    "Do we (you) know John if the difference between what we are producing and what is being dealt with is increasing? "
    This paper deals with that (yes, it is increasing (both emissions and sinks are growing, but the former faster than the latter)): "Changes in the long-term efficiency of the natural sinks in removing atmospheric CO2, as measured by the ratio of sinks to emissions, are indicated by the proportional trend in the AF [(1/AF)dAF/dt]. Over the period 1959–2006, this was +0.25 ±0.21% y-1" "We estimate that 35±16% of the increase in atmospheric CO2 growth rate between 1970–1999 and 2000–2006 was caused by the decrease in the efficiency of the land and ocean sinks in removing anthropogenic CO2 (18 ± 15%) and by the increase in carbon intensity of the global economy (17 ± 6%). The remaining 65 ± 16% was due to the increase in the global economy."
  45. CO2 is not the only driver of climate
    Thermodynamics applies to heat. Objects composed of vibrating atoms and molecules rearrange themselves when in direct contact according to the laws of thermodynamics depending upon how "hot" they are. Hot material objects or portions of them move about according to how hot they are in abidance with the Law. Electromagnetic radiation is not material and it is not heat. The Second Law does not apply. The atmosphere is warmed primarily by the Earth's solar warmed surface through radiation, conduction and convection. Only conduction and convection are restricted by the Second Law. The atmosphere does not warm the surface the same way as the surface warms the atmosphere. Generally speaking the cooler atmosphere can not conduct or convect warmth to the surface, but it can and does radiate to the surface because it has a temperature above absolute zero. There are four ways to end up with a warmer object, direct strong radiation toward it as for example the Sun does during daytime or place a warmer object in direct contact with it so that conduction and convection can take place. The fourth way is to allow or force the object to cool more slowly once it has been warmed by the first three. The greenhouse effect works by means of the fourth option. Take away the first three and the greenhouse effect will not work since it produces zero energy. Take away the Sun and none of the options work. ---- "All bodies that have a temperature will produce an Electromagnetic Field WAVES...continuously." All dense matter with a temperature will produce a continuous spectrum of ER. The emission by free electrons, atoms and molecules is not continuous as required by quantum mechanics. The discreet emissions of ER are smeared into a continuous spectrum by the density and temperature of the matter. For the same reasons, all dense matter regardless of temperature can absorb the full spectrum of ER or very nearly so if it is close to a perfect black body, which the Earth is.
  46. ACRIM vs PMOD, the rematch
    solar magnetograms? http://www.iop.org/EJ/article/1755-1315/6/9/092016/ees9_6_092016.pdf?request-id=8e517d78-d0ca-42ea-8628-27ee1c1f3eca Katya Georgieva “The role of the sun in climate change” Earth and Environmental Science 6 (2009) 092016 doi:10.1088/1755-1307/6/9/092016
  47. CO2 is not the only driver of climate
    Gord, "cancellation" of waves, better know as destructive interference, is a local effect. Whenever the two waves happen to be in different places they are undisturbed by the preceding interference. This is what the principle of superimposition means. And rememeber, waves, not energy fluxes.
  48. The albedo effect
    "In the common period, earthshine, CERES along with ISCCP-FD data show a trendless albedo. However, preceding CERES, earthshine and ISCCP-FD reflectances show a significant increase before flattening and holding the increase. This implies a reduction in the net sunlight reaching Earth. In the context of the recent climate change, it is important to point out that the physical causes behind these large decadal variations in albedo are still unknown, and that we just don't know yet whether we should expect the albedo changes observed during the modern period to persist into the future." (Palle 2008) Project Earthshine includes the observatory at Mt Teide (Gran Canarias)not just BBSO and they reckon to have almost global coverage. In addition they have another observatory in partial use in Crimea. A further proposal to set up an earthshine project in Antartica ( which would give 6 days of un-interrupted data)was put forward in 2004 but seems to have died a death. If you access the original graph the time series goes back to 1985 and shows a distinct drop in albedo in 1998 - a very hot year. Yes, the current data shows little change in albedo (from 2000..so what?) but that long term trend of -0.7W is still there and just happens to balance the +0.7W heat being added to the oceans.....
  49. CO2 is not the only driver of climate
    PS: Heat Radiation Radiation is heat transfer by the emission of electromagnetic waves which CARRY energy away from the emitting object. For ordinary temperatures (less than red hot"), the radiation is in the infrared region of the electromagnetic spectrum. The relationship governing radiation from hot objects is called the Stefan-Boltzmann law: http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/stefan.html#c2 --- Properties of electromagnetic waves "An electromagnetic wave, although it CARRIES no mass, does CARRY energy." "A more common way to handle the energy is to look at how much energy is CARRIED by the wave from one place to another." http://physics.bu.edu/~duffy/PY106/EMWaves.html --- Heat flux "Heat flux or thermal flux, sometimes also referred to as heat flux density or heat flow rate intensity is a flow of energy per unit of area per unit of time. In SI units, it is measured in [W·m-2]. It has both a direction and a magnitude so it is a vectorial quantity." http://en.wikipedia.org/wiki/Heat_flux ----------------------------------------------- All bodies that have a temperature will produce an Electromagnetic Field WAVES...continuously.
  50. CO2 is not the only driver of climate
    Cancellation and Black Body Radiation. Blackbody Radiation "Blackbody radiation" or "cavity radiation" refers to an object or system which absorbs all radiation incident upon it and re-radiates energy which is characteristic of this radiating system only, not dependent upon the type of radiation which is incident upon it." The radiated energy can be considered to be produced by standing wave or resonant modes of the cavity which is radiating." http://hyperphysics.phy-astr.gsu.edu/hbase/mod6.html#c1 Last time I checked, resonance and standing waves were a result of interference....so is cancelation of waves!!

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