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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 87251 to 87300:

  1. CO2 effect is saturated
    RW1 - Your erroneous "halving" has been addressed repeatedly, you have simply chosen to disregard the answers you have received. 3.7 W/m^2 is the drop in IR emitted to space for a doubling of CO2. This is due both to the rise in tropopause and effective emission altitude from increased CO2 concentration (and hence lower CO2 emitting temperature) and absorption band expansion. The window decreases slightly, but the predominant change is decreased emissions across the CO2 absorption bands. Hence "If the net effect at the surface is 3.7 W/m^2, then the "window" should close by 7.4 W/m^2 when CO2 is doubled" is simply wrong. There are two effects, not one, and your insistence on assigning all change to one effect has been corrected over and over again. Anyone interested in that discussion should look at the Lindzen and Choi thread, where RW1 and others were informed of the details over 448 postings. Please do not rehash that here. This thread is about CO2 saturation, and it is hence off-topic.
  2. Berényi Péter at 08:17 AM on 26 April 2011
    It's not bad
    #117 Albatross at 07:12 AM on 26 April, 2011 of course, not linked Here is the full exchange (open access).
  3. CO2 effect is saturated
    I should say the "window" should decrease by 7.4 W/m^2 when CO2 is doubled (not close). Trenberth et al 2009 has the window being 70 W/m^2 with the atmosphere emitting 157 W/m^2 down and 169 W/m^2 up (48% down and 52% up), if your interested in running some numbers.
  4. CO2 effect is saturated
    novandilcosid (RE: 110), If the net effect at the surface is 3.7 W/m^2, then the "window" should close by 7.4 W/m^2 when CO2 is doubled.
  5. CO2 effect is saturated
    novandilcosid (RE: 110), "I note in passing that increased Radiative Forcing (=energy inbalance at the Tropopause) is entirely different to increased absorption of Surface Energy, so that Tom's entire post is a confusing non-response to the question. Does anyone have a figure for the decrease in Surface Energy passing through the window due to a doubling of CO2 and assuming no temperature change at the surface?" The figure is 3.7 W/m^2. When CO2 is doubled, the window (i.e. transmittance) reduces by 3.7 W/m^2 and the atmosphere absorbs an additional 3.7 W/m^2 of surface emitted radiation, half of which goes down to the surface and half of which goes up out to space (1.85 W/m^2 up and down). It has been claimed here and elsewhere that the halving effect is already accounted for in the 3.7 W/m^2 figure; however, I have not been able to verify this through numerous inquiries to the climate science community. No one can give me a straight answer, but I'm still working on it.
    Moderator Response: (DB) In reality, you were given an answer, which you have chosen to ignore.
  6. Extreme weather isn't caused by global warming
    Again it would be prudent to compare what changes may be appearing now with those that confronted the Ancient Pueblo People that led to their displacement. This an excerpt from an article examining the Anasazi Collapse "Studying tree rings from 27 sites across the Southwest, Dr. Jeffrey Dean of the University of the Arizona tree-ring laboratory has found evidence of a major disruption in the area's typical rainfall. Suddenly, the customary pattern of heavy snows in the winter followed by summer monsoons had become unpredictable. Even if there was not a great drought, moisture may have been coming at the wrong times. The summer rains, so necessary to keep the spring crops from dying, were no longer reliable."
  7. It's not bad
    Please note, re the critique of the phytoplankton paper by Boyce et al. (2010) cited @116: Boyce et al's response to the critique was, of course, not linked.
  8. Berényi Péter at 06:57 AM on 26 April 2011
    It's not bad
    Would you please update this reference under Environment in the Intermediate version of the post? Decline in global phytoplankton (Boyce 2010) It is thoroughly debunked (see all three Brief Communications linked on the paper's page at the Nature site, April, 2011). Phytoplankton in fact is not declining.
  9. Daniel Bailey at 06:45 AM on 26 April 2011
    Wakening the Kraken
    @ muoncounter: Mark-US's linked source is on-topic. A preliminary read is interesting. I have some issues with parts of it, but reserve full judgement until I've had a chance to review it properly. Open copy available here (for now, anyway). Thanks, Mark! The Yooper
    Moderator Response:

    [muoncounter] That link takes me to a blank scribd doc.

    [DB] Sorry, muoncounter; I've checked it several times and it works for me. Dunno what to say.

  10. Wakening the Kraken
    Re #23.... sorry, try these active links The Paleocene-Eocene Thermal Maximum: A Perturbation of Carbon Cycle, Climate, and Biosphere with Implications for the Future Fossil Sirenians, Related to Today's Manatees, Give Scientists New Look at Ancient Climate
    Moderator Response: [muoncounter] Please provide some context for your links.
  11. Extreme weather isn't caused by global warming
    Continued from here: But while the world has got hotter in the past 100 years, Nielsen-Gammon said, Texas rainfall has actually gone up by about 10 per cent. Much of it has come from more-frequent extreme rainfall events rather than a general increase in normal rain. This is the pattern that seems to be emerging: More frequent higher intensity events, rather than a monotonous increase. In the case of current droughts, long weeks and months of dry weather punctuated by heavy rain. Those 'gully washers' make the statistics even out, but mostly result in runoff rather than soaking rain.
  12. Wakening the Kraken
    I'm deeply grateful for your work here at Skeptical Sci! Intending to help, I'd like to quibble with two parts of this post: "massive extinction of animals, most recently at the time of the Paleocene-Eocene Thermal Maximum (PETM), about 55.8 million years ago." "Resulting hypoxic conditions would cause large extinctions, especially of water breathing animals, which is what we find at the PETM." In this year's Annual Review of Earth and Planetary Science, the authors claim that extinctions were pretty much limited to benthic forams. The ranges of other life forms were re-arranged. By which I mean "extensively and painfully" rearranged. But they survived. Apparently it is a misperception to assign mass-extinction to the PETM. See also http://www.sciencedaily.com/releases/2011/04/110421161725.htm
  13. A Convention for Persons Displaced by Climate Change
    Everyone, I think that we should defer the last word to the experts regarding the Texas drought and wildfires. This is what Dr. Nielsen Gammon (Texas state climatologist and eminent climate scientist) and Dr. Hayhoe (climate scientist) have to say. Personally, I am far more concerned about the tens of millions of environmental refugees around the world than these fires.
    Moderator Response: [muoncounter] Take the drought discussion to the extreme weather thread.
  14. Harry Seaward at 04:19 AM on 26 April 2011
    A Convention for Persons Displaced by Climate Change
    Muon @ 56 and Sweet @ 61 Our information on the weather and rainfall disagree. We agree on the drought. Please review the following info and tell me if you still disagree. Winter Weather: From the NY Times on Texas weather from the winter of 2011 "Though a February snowstorm is not unusual in North Texas, this one followed an ice storm on Tuesday and three successive days of frigid temperatures. As a result, the ground was cold when the snow hit, and there was still ice on many roads, according to state traffic officials and forecasters with the National Weather Service. “Our temperatures rarely stay this cold for this long,” said Bill Bunting, the meteorologist in charge at the National Weather Service office in Fort Worth." Rainfall Totals: From the NOAA website for Lubbock, TX "Another way to put the rain into perspective is to look at the percent compared to normal. The below map shows that most of Oklahoma and Texas saw well above normal during the two week span from late June through early July 2010. Much of the South Plains and Rolling Plains received an astounding 400 to 800% or more of normal. The exception was across the southwest Texas Panhandle and extreme northwest South Plains where totals were near or just slightly above average for the two week period."
  15. A Convention for Persons Displaced by Climate Change
    If discussion of drought in Texas is allowable in this thread, then it should be put into historical perspective against those earlier civilisations from the region that were displaced by drought, for example, the Ancient Pueblo People and the Mayans, and the relevance of the 300 year drought, known as the Great Drought that began around 1150. What differentiates any recent changes in precipitation patterns to such earlier changes?
  16. Cosmic ray contribution to global warming negligible
    @rhjames: In addition to the other comments, it appears that you are ignoring nighttime effects. Surely you don't dispute that nighttime clouds have a warming effect.
  17. Daniel Bailey at 02:55 AM on 26 April 2011
    A Flanner in the Works for Snow and Ice
    The warming anomaly in the high Arctic is quite apparent in the DMI data: [Source] And in the overall temperature anomaly over time: [Source] Yields a declining winter maximum Arctic Sea Ice extent over time: [Source] Resulting in a declining Arctic Sea Ice cap: [Source] Melting ice cares not for sophistry. Or is it that Arctic Sea Ice declines from it's current winter maximum of about 13.5 million square km area to it's melt season low of about 4.2 million square km out of sheer habit...: [Source] As much as I'd like to vote for sheer habit, I'm going with the physics-based insolation & the damage it inflicts on the ice...and the resulting changes in albedo over time. The Yooper
  18. A Flanner in the Works for Snow and Ice
    Ken Lambert @128, the sea ice does not start melting at the beginning of summer, and nor does it magically return to the winter state at the end of summer. Further, there is less winter sea ice in the arctic now than 30 years ago. Therefore your adjusted sea ice area calculation is nonsense. For what it is worth, on average over winter, there was 0.63 million square km less sea ice over the period 2004-2008 than the period 1979-1983. There was, on average 1.08 million square kilometers less in the spring. There was 2.04 million square kilometers less on average in the summer. There was on average 1.69 million square kilometers less in the Autumn. Even if these where the minimum seasonal extents, therefore, that would only represent a 25% reduction in the calculated energy, not the 50% you calculate. However, these are not the minimum values, but the average value taken over the season. Early in the summer there is less than 2 million square kilometers exposed, but late in the summer there is significantly more than an extra 2 million square kilometers exposed. The average over the whole season is an extra two million square kilometers. So, there is no need to adjust the figure to find the average, for the figure is already the average. These figures are based on the seasonal sea ice extent data linked @88. I extrapolated the autumn 2008 figures to determine the average by adding the average difference between summer and autumn ice to the summer ice of 2008. Prior to using those figures, I had based my calculations on, first, the area of the difference in latitude band taking the month of the season with the least change of latitude (based on the chart in 58) and on sea ice area graphs compared over a season choosing the minimum difference for the season. Neither method was entirely accurate but where conservative. I find it gratifying that the one figure I have not had to change over the whole exercise, though I have used three entirely different and conservative methods to determine it, is the difference in sea ice.
  19. A Flanner in the Works for Snow and Ice
    Sorry- accidental 'Enter' posting at #123 Tom Curtis: Here are your assumptions as I understand them: 1) Your 97W/sq.m is based only on average incoming energy flux due to the difference in albedo from Sea Ice compared with Seawater for an range of incidence angles over the Arctic Summer above 75 degrees N latitude. 2) The Area of additional Sea Ice melt is assumed to be 2 million sq.km melted over the period 1979 - 2011 (32 years) 3) The whole 2 million sq.km is assumed to be exposed to the 97W/sq.m for the length of the Arctic summer (90 Days) 4) No account is taken of any change of outgoing energy flux due to surface temperature increases in the 90 day period. 5) No acount is taken of transfer of heat to the Arctic by other means (ocean currents eg.) Based on these assumptions you then calculate the total energy absorbed over a 90 day Arctic summer as follows: 97W/sq.m x 90 days x 24 hr/day x 3600 seconds/hour = 7.54E8 Joules/sq.m. You then multiply 7.54E8 Joules/sq.m x 2 million sq.km (2E12 sq.m) = 1.51E21 Joules. (15.1E20 Joules). So far, this matches your number. Now, the same problem arises with the additional 2 million sq.km melted relative to 1979. It did not all happen in one summer season. It is not in linear increments for 32 years, but not all in one summer either. But even if we heroically assume an extra 2 million sq.km was melted in ONE 90 day summer, then the 2 million sq.km of extra Seawater is only fully exposed at the END of the 90 day period. The melt curve is roughly sinusoidal with time. If you break up the summer into 3 x 1 month periods, and assume a linear approx for the decline in ice area, then after 1 month you will expose 1/3rd of the 2 million, after 2 months 2/3rds of the 2 million and, after 3 months the whole 2 million. Whichever way you break it up, the average area exposed to the 97W/sq.m is HALF the 2 million sq.km. for the 90 day period. Hence your 15.1E20 Joules should be half that: about 7.6E20 Joules per 90 day summer - making the heroic assumption that the whole 2 million sq.km is melted and Seawater exposed in one summer. Dr Trenberth says in his "Tracking the Earth's Energy" Aug09 paper: Quote "Sea ice is important where it forms. Record losses of Arctic sea ice of about 10^6 km2 occurred in summer of 2007 relative to the previous lowest year [25], although the thickness and volume of the ice is quite uncertain. To melt 10^6 km2 of ice 1 m thick and raise the temperature of the water by 10 degC requires 3.4 x 10^20 J, or globally 0.02 W/m2. For 2004–2008 this is about 0.9 x 10^20 J/yr." Endquote So if we assume that the worst year (2007) melted a 1 million sq.km area then we HALVE the 2 million area and the calculated figure of 7.6E20 Joules to a number of 3.8E20 Joules in one 90 day summer. This is quite close to Dr Trenberth's number of 3.4E20 Joules needed to quote "melt 10^6 km2 of ice 1 m thick and raise the temperature of the water by 10 degC requires 3.4 x 10^20 J" With a global imbalance of 145E20 Joules/yr, the 3.8/145 equals 2.6% of the planet's warming from the melting of 1 million sq.km of Arctic sea ice in one summer (year). This similar to the 2.8% I calculated previously.
  20. A Flanner in the Works for Snow and Ice
    les @125, having investigated that possibility I have discovered that Google docs won't recognize Open Office files for import; and that a cut and past transfers values only, not formulas, which is pretty useless. It is IMO not worth my time to redo my spreadsheet again from scratch for the benefit of someone who is being at best, obtuse.
  21. A Flanner in the Works for Snow and Ice
    Ken Lambert @123:
    "1)Your 97W/sq.m is based only on average incoming energy flux due to the difference in albedo from Sea Ice compared with Seawater for an range of incidence angles over the Arctic Summer above 75 degrees N."
    The highlighted phrase is ambiguous. Do you intend to indicate that I only calculated the difference in incoming energy between the early 1980s and the last few years that resulted from the reduced summer sea ice? Well, if so, yes. That is in fact what I have stated all along that I am calculating. Alternatively do you intend to say that I only took albedo into account in calculating this value? But that is a ridiculous statement given that I had just spent several paragraphs explaining the total number of factors I had taken into account including, path length through the atmosphere and consequent atmospheric absorption, cloud albedo, the relative footprint of solar radiation given the high latitude, and even the orbital eccentricity; with formulas given for how I handled each factor. Further, it is not just any range of angles of incidence. It is a range of angles that is traversed during an arctic day which underestimates the altitude of the sun for each time interval. Finally, you do not call the results of a calculation an assumption.
  22. A Flanner in the Works for Snow and Ice
    Tom, Ken; why don't you set up a google docs spreadsheet (maybe under an anonymous account or two) and plug your numbers / equations in? you could both edit it (it has track changes) and see if you can converge to an answer?
  23. A Flanner in the Works for Snow and Ice
    Mod, I purposely did not direct my comment at anyone in particular. I made a broad, general statement. You are free to delete the comment, if you see fit. I did hesitate for some time before hitting submit, weighing the alternative of simply disappearing from the thread in silence. But I felt that it needed to be explicitly said.
  24. A Flanner in the Works for Snow and Ice
    Tom Curtis #121 t looks like I will have to sort this out for you Tom, sonce you won't show your exact calculation: This is what you say you did at #73: "4) From the half hourly values obtained in (3), I calculated the additional energy absorbed by ocean surface exposed by melting sea ice as the difference between the albedo (0.9) of the sea ice and the albedo of the ocean given the angle of incidence, multiplied by the effective surface radiation (as calculated in 3). Taking the mean of that value, the average additional power absorbed by the ocean is 97 W/m^2. 5) Using that value, I calculate the total additional energy absorbed as 7.57 x 10^8 Joules per meter squared over a notional 90 day summer, or 1.51 x 10^21 Joules over the whole 2 million square km of additional ice cap melted over the period 1979-2011." Here are your asumptions as I understand them: 1)Your 97W/sq.m is based only on average incoming energy flux due to the difference in albedo from Sea Ice compared with Seawater for an range of incidence angles over the Arctic Summer above 75 degrees N.
  25. A Flanner in the Works for Snow and Ice
    I will not engage with anyone who demonstrates a blatant and total lack of integrity. I would hope that casual readers will recognize these traits for what they are, when demonstrated, regardless of that person's position, and so take anything stated by that person either now, previously, or subsequently with an appropriately healthy degree of skepticism. Trust should not be blindly given to those who simply state what you wish to believe. If anything, those are the people for whom the bar should be set highest, because they have you at a disadvantage, and so can take advantage of you most easily and completely.
    Moderator Response: [mc] While you are certainly free to question another's statement and advise others to question them, questioning personal integrity is not necessary.
  26. michael sweet at 23:33 PM on 25 April 2011
    A Convention for Persons Displaced by Climate Change
    Harry, When I checked the NCDC Climate Monitoring Page I do not see mention of extraordinary cold in Texas last winter. Muoncounter at 56 provided data to show your claim of extra rain from Hurricane Alex is false. This leaves the drought which has been long predicted by climate scientists for this area of the USA. The NCDC mentions the drought a lot. You have not linked any sources to support your claim that rain and cold contributed to the Texas wildfires. Can you provide links to support your assertion of a greater cause than the drought? Since scientists have predicted AGW caused drought for Texas and the primary cause of the wildfires is drought, it seems to me that AGW is the prime suspect in the cause of the fires. As you point out, area wise these fires are historic in size, and they are not out yet. We have to wait to see what the final toll is. Often evidence is not 100% linked to the cause. We need to look at the most likely explainations and not expect absolute proof. As the list of items becomes longer and longer that must be explained it becomes more and more certain that AGW is linked to these occurances. There is no proof that the last three years of flooding on the Red River in North Dakota is caused by AGW, but how likely is two consecutive 100 year floods after a 50 year flood? This has to be assessed with the 1:1000 year floods in Pakistan and 1:1000 year heat in Russia in mind. It has become too frequent for normal chance. There has not yet been enough time for scientists to peer review analysis showing last years (or this years) problems are linked to AGW, but that does not mean they are not linked. We will have to wait for the analysis to be published.
  27. Geologist Richard Alley’s ‘Operators Manual’ TV Documentary and Book… A Feast for Viewers and Readers
    I understood this is just the first of a series. Does anyone know when's the next to come?
  28. Eric (skeptic) at 21:58 PM on 25 April 2011
    Cosmic ray contribution to global warming negligible
    Alexandre, thanks for the clarification. My view is also that 20th century warming cannot be attributed to GCR. GCR affects the weather in the short run which may result in cooling or warming locally (since cloud modulation effects depend on the location). I don't think it's a very strong effect relative to direct forcings like GHG, especially looking at it globally.
  29. Wakening the Kraken
    I'm sorry hack Tennysons' poem, but this is supposed to be a science site: Below the thunders of the upper deep; :refers to the location of clathrates, usually a bit lower than the deeps of continental shelf, in Siberia however clathrates can form in shallower locations, but Tennyson doesn't know this Far far beneath in the abysmal sea, :again referring to the deepness of the layers, in 1830 there weren't to many deep sea explorations, maybe Tennyson was on a ship that did that? His ancient, dreamless, uninvaded sleep :personifying the clathrates, there's been at least 55 million since the last global clathrate gun reaction. The Kraken sleepeth: faintest sunlights flee :Maybe the ship Tennyson was in tried to measure the continental drop by dropping some light emitting stuff in the ocean. About his shadowy sides; above him swell Huge sponges of millennial growth and height; :probably refers to the algae present on these locations that can be quite large, though they're not millennial creatures. And far away into the sickly light, From many a wondrous grot and secret cell :this sounds more like some reef Unnumber'd and enormous polypi :that still has corals and stuff like Winnow with giant arms the slumbering green. :ocean fans, 'slumbering green' - ocean, Tennyson gets poetic ;-) There hath he lain for ages, and will lie :Back to 'Kraken' alias a singular methane clathratre deposit on the continental drop of Western Atlantic Battening upon huge seaworms in his sleep, :maybe they found some hagfish on the location? Until the latter fire shall heat the deep; :the reaction in the local deposit when their flaring probe hit the bottom. Then once by man and angels to be seen, :it must be quite an experinece to see a methane blow-out nearby. In roaring he shall rise and on the surface die. :the local deposit wasn't a big one and was triggered by the flare, not a current.
  30. Antarctica is gaining ice
    RyanStarr, it should be self-evident that ice trends would only follow temperature trends between the time that the temperature was sufficient to cause ice melt and when it was sufficient to have melted ALL the ice. Thus, your insistence that the 'failure' of the Antarctic ice trend to follow the temperature trend over the past 100 years is significant would only be logical if Antarctic ice were melting that entire time... which it wasn't. As to: "the anomaly today sits where it started 12 years ago, yes mostly steady" By that reasoning we would be forced to conclude from a 55 degree day in February and a 55 degree day in May that the temperature had been "mostly steady" over the intervening three months. Any rational person should know better.
  31. CO2 effect is saturated
    novandilcosid, I note again that you are not really arguing that the CO2 greenhouse effect is saturated... you are arguing that it does not exist at all. Yet you have refused to respond to the obvious questions that raises: 1: Why do Spencer, Christy, Pielke 1&2, and every other 'skeptic' scientist (not to mention all mainstream scientists and all physics texts on the subject) claim that CO2 DOES cause the planet to be significantly warmer than it would be without? 2: If CO2 and other atmospheric gases can only slightly decrease the amount of radiation reaching the surface and thus cause slight cooling as you claim, then why is the Earth more than 30 C warmer than could be explained by sunlight hitting an airless rock at this distance from the Sun? You stand at odds with nearly two centuries of scientific understanding. How do you explain that? You argue that energy in must equal energy out (though this isn't true when a system is not in balance), but ignore the fact that this says nothing about the actually relevant issue of energy within the system. Consider a house (or planet Earth) which is receiving a fairly constant influx of energy from a furnace (or the Sun). Once equilibrium is reached the energy leaving must be equal to the energy entering... but the amount of energy within the system can be very different depending on how much insulation (or greenhouse gases) it has. One constant energy source... constant energy emission from the system... but DIFFERENT amounts of energy within the system and therefor different temperatures. Ergo all your arguments about energy in and energy out are irrelevant. The question at hand is energy within the system.
  32. CO2 effect is saturated
    novandilcosid at 15:19 PM on 25 April, 2011 David Archer (Univ. Chicago) made available online an older version of Modtran. I'm not sure how accurate it is, but you may find it a helpful tool to play around with that kind of hypothesis.
  33. Cosmic ray contribution to global warming negligible
    Eric #20 I also accept that GCR can have some effect on climate. Richard Alley himself seemed to accept that possibility in the lecture I mentioned above. But regarding the present warming, there are many lines of evidence today pointing to GHG, and scarce evidence (If any) pointing to GCR, whatever effect the latter proves to have in the future. I'm not saying you claim otherwise, I just wanted to state my bottomline clearly.
  34. A Flanner in the Works for Snow and Ice
    Ken Lambert @119 says:
    "What you and Tom are missing all through this thread is that angles of incidence above 40 degrees (where you claim albedo drop off becomes significant) only occur at midday below a latitude of 73 deg N (ie; 23 +/-17) on one day of the year.
    What you have been obtusely ignoring, Ken, is that the albedo effect on which you rely is far smaller than you seem to think. Specifically, the average albedo on smooth water over the full day of 21st May at 75 degrees North is only 0.328 compared to the 0.9 albedo of snow covered ice. That average is conservative in that it is calculated using the lowest angle above the horizon for each half hour period of the day. Further, on wavy water, as for example, the sea, the albedo is significantly less than that. This is because light striking a facing slope of the wave will strike at a much smaller effective angle of incidence (ie, closer to perpendicular to the water face) and hence have a much reduced reflectivity. Light striking the opposite slope will be reflected at a shallow angle, and have a high probability of striking the facing slope of the next wave, and hence being absorbed. Treating the ocean as a non-wavy surface probably overstates the albedo by 40%. What is more, the period of highest albedo is also the period of lowest incidence of light. That is a very substantial effect. If we take the average of the albedo using my conservative estimate only over the 15 hours in which the sun is highest in the sky, the mean albedo falls to 0.17, or 0.73 less than the case of snow covered ice. This is particularly significant in my model in that it is so conservative as to estimate no sunlight in the other nine hours of the day, even with the sun still being in the sky. What has been most striking about your behaviour in this discussion is that you regularly insist a particular effect is substantial while making no attempt to actually calculate it. And when it is calculated, and your point is shown thereby to be without substance, you quibble about minor points while accepting gross biases in the calculation in your favour without any qualm. For instance, you quibble about Sphaerica (and my) admitted error about the angle of incidence which results in a change in average albedo of just 0.3, and hence overestimates incoming energy flux by 50% at most. In the meantime you happily accept all the biases I introduced into my calculations in your favour without qualm, even though they probably underestimate the incoming energy flux by a factor of 3.85 or more. And in the meantime you pester after a statement of how my calculations where achieved (which has already been given in more than sufficient detail) because you cannot refute and find your position refuted by them.
  35. A Flanner in the Works for Snow and Ice
    Tom Curtis #118 OK, take me through the calculation showing all the terms you used to get the 1.51 x 10^21 Joules at #73.
  36. A Flanner in the Works for Snow and Ice
    Sphaerica #102 This is bizarre. I must be in a parallel universe. You are claiming the exact opposite of what actually happened: Viz: "As far as yot opposite of your angle of incidence claims, anyone here can go back and read the thread. I already corrected you several times on that. You are focused on the exact spot of the north pole, when the area of interest is that entire area from about 50˚N and up." The area of interest is the Arctic. 66 degN and up. Tom's area of interest was the edge of the Arctic sea ice at 75 degN and up. I had to direct Tom to a calculator so he could correct his erroneous angle of incidence claims as well. The Earth still turns once every 24 hours - even up in the 'tropical' summer Arctic. At 75 degrees N the summer angle of incidence will be 23 +/-15 degrees on July 23. At 66 deg N it will be 23 +/-23 degrees on July 23. (The Arctic circle where it is 0 degrees at midnight on one day of the yesr) At 50 deg N it will be 23 +/- 40 degrees on July 23. When the angle goes negative Sphaerica - it is dark - nighttime. Lots of IR goes out to space at night. So it is simply wrong to claim that I am only focussing on the exact spot of the North Pole. What you and Tom are missing all through this thread is that angles of incidence above 40 degrees (where you claim albedo drop off becomes significant) only occur at midday below a latitude of 73 deg N (ie; 23 +/-17) on one day of the year.
  37. A Flanner in the Works for Snow and Ice
    KL @117, I again refer you to my posts 73 and 88. I showed how I obtained the figures in 54 in 54, but I see no point in reviewing figures for which I have obtained a more accurate result.
  38. A Flanner in the Works for Snow and Ice
    Tom Curtis #109 Show me how you got to 2.2E21 Joules in your original calculation at #54?
  39. Muller Misinformation #1: confusing Mike's trick with hide the decline
    152 Ryan I did not respond directly to your question because it had nothing to do with the issue of whether graphs should be perfectly self interpreting. simple. Had you wanted to you could have inferred from my input, my answer; if the method section of a paper does not properly describe the techniques and data used, which may or may not be shown in a pretty picture, the paper is at fault. The reason I emphasise this - and fir my input on this subject a few times, is that a lot of people seem to think the work all about looking at graphs. This is because that is how a lot of scientists illustrate their story (which is fine); but the real story is in the words and equations nit the illustrations.
  40. novandilcosid at 15:19 PM on 25 April 2011
    CO2 effect is saturated
    In response to my question "Does anyone have a figure for the decrease in Surface Energy passing through the window due to a doubling of CO2 and assuming no temperature change at the surface?" DB wrote: " Your final assumption is flawed so your question is meaningless" The whole of this thread is about how much the window closes (note: not about the export to space but about the absorption of radiation). I'll ask the question a different way: "What is the percentage change in the proportion of surface radiation absorbed by CO2 for a doubling of CO2?"
    Response:

    [DB] As the OP shows, the whole of this thread is about:

    "If the CO2 effect was saturated, adding more CO2 should add no additional greenhouse effect. However, satellite and surface measurements observe an enhanced greenhouse effect at the wavelengths that CO2 absorb energy. This is empirical proof that the CO2 effect is not saturated."

  41. CO2 effect is saturated
    novandilcosid @110, your post to which I responded asked both about the change in transmittance (aborption of surface radiation), and the change in atmospheric emissions at the top of the atmosphere. This first was shown clearly in post 82. The combined effect was clearly shown in my first figure @108. You dismiss that because that highly relevant data was not in the exact format your required to impose your spin. You at the same time simply ignore the impirical data that refutes your thesis. Well, your game is now very clear, and it is not honest inquiry. If you ever want to try that, run a full Line By Line calculation of the emissions spectrum (as has been done by the people whose results you simply dismiss), and then if you come up with an interesting result, try again. In the mean time, I am not interested in pretending the partial calculation of a result on the back of an envelope can in any way refute the full calculation of the result with computers using a variety of methods, all coming up with essentially the same result.
  42. novandilcosid at 15:13 PM on 25 April 2011
    CO2 effect is saturated
    DB reponded to my post at #109 with "Except that the energy balance at the TOA is not balanced; thefore the planet is not in equilibria in its energy budget. Your argument therefore fails this initial test." He is sort of correct: on short timescales and at particular locations, the planet is not in equilibrium with Space. The energy balance changes from positive to negative all the time. But INTEGRATED on long timescales that balance has to be stable. Otherwise the planet will change to make it so. For example over the last 10 years the planetary average temperature has not changed. So the integration of energy input/output will be balanced or nearly so. That's what the Kiehl & Trenberth diagram used by the IPCC in 2007 says. (or are we saying that the IPCC was wrong to use that diagram?) I fail to see therefore why my innocous observation that there is no change in surface energy into the atmosphere is invalidated.
    Response:

    [DB]

    "But INTEGRATED on long timescales that balance has to be stable. Otherwise the planet will change to make it so." 

    On very long timescales, it is in balance.  Right now, due to the forcing from CO2, it is not.  So the planet is seeking to regain that balance by raising the tropospheric temperatures as well as sequestering heat/energy into the oceans.  This is very basic, PRATT stuff.

    "For example over the last 10 years the planetary average temperature has not changed."

    Incorrect.  This fails on multiple levels:

    1. The global temperature record shows the most recent 10 year period as the hottest in the instrumental record.
    2. Selecting a short 10 year period is cherry-picking, as that period is typically too short to carry statistical significance.  However, allowing for exogenous factors, the planet has shown statistically significant warming since 2000.

    I fail to see, therefore, why you cannot see your position is invalidated from the initial premise.

  43. novandilcosid at 15:04 PM on 25 April 2011
    CO2 effect is saturated
    Tom Curtis posted at #108: "The result in zero net change in the OLR." Working again on the model of a planet where energy flows are integrated over the surface for a year, then averaged, and assuming the planet is in energy equilibrium with Space, we can write: Sunlight hittng the planet = reflections + sunlight absorbed then reradiated. or, put another way, Sunlight hitting the planet = Outgoing Shortwave Radiation (=reflections) + Outgoing Long Wave Radiation (sunlight absorbed and reradiated) It is clear from this that OLR varies only if the Earth's albedo changes. It is sometimes claimed that the warming effect of GHGs must mean OLR is increasing or perhaps decreasing. But not in an equilibrium planet with no change in cloud or ice cover.
  44. A Convention for Persons Displaced by Climate Change
    Harry Seaward @61, I gather that the terms "environmental refugees" and "climate refugees" are not differentiated in the literature, which I believe is bad practice. Of the 36 million environmentally displaced persons due to sudden onset catastrophes in 2008, 20 million where displaced by climatological effects, and of course the unknown number displaced by slow onset catastrophes (droughts, soil salinity) are primarily are all displaced by climatological effects. That suggests at least 5 million more displaced because of climatological effects than would have been displaced without climate change. As an upper limit, as many as 14 million more people may have been displaced as a result of climate change in 2008 than would other wise been displaced. However those figures are just guesses based on approximate ratios only. Nobody, SFAIK, has published anything like a secure estimate. The number displaced that would not have been displaced without climate change is likely to have been much larger in 2010. I do not have even the insecure figures for 2010 that I have for 2008, but the total number effected by natural disasters is comparable (208 million in 2010 compared to 214 million in 2008), and the largest disaster in terms of number effected was a flood in 2010 (134 million effected) while the largest disaster in 2008 was an earthquake, also in China (15 million displaced). Therefore a much higher proportion of those displaced in 2010 were displaced by climatological effects, and consequently more of those displaced are likely to have been impacted by global warming. (The additional data for 2010 is from the Brookings Institution/ London School of Economics report on environmental displacement in 2010, which give figures for those effected, but unfortunately, not for those displaced.) To summarize, the information we have strongly suggests that people are being displaced in large number by the effects of climate change already; but they are not secure enough to quantify how large an effect that is with any sort of accuracy.
  45. novandilcosid at 14:53 PM on 25 April 2011
    CO2 effect is saturated
    Tom Curtis posted at #108: "novandilcosid @99 asks, ""[H]ow much additional surface energy is absorbed outside the saturated 625-725 band, ie by how much does the window close, in W/m^2?" The following chart from SOD shows the change in net forcing from a doubling of CO2... I note in passing that increased Radiative Forcing (=energy inbalance at the Tropopause) is entirely different to increased absorption of Surface Energy, so that Tom's entire post is a confusing non-response to the question. Does anyone have a figure for the decrease in Surface Energy passing through the window due to a doubling of CO2 and assuming no temperature change at the surface?
    Moderator Response: (DB) Your final assumption is flawed so your question is meaningless.
  46. novandilcosid at 14:47 PM on 25 April 2011
    CO2 effect is saturated
    Tom Curtis responded at 107 to my very clear post at #104 in which I said: "Solar_Radiation_Absorbed_into_the_Surface = Surface_Energy_Absorbed _into_the_Atmosphere + Surface _Energy_Radiated_through_the_Window_to_Space The LHS of this equation is only affected by the solar constant, atmospheric absorption of sunlight, and planetary albedo. [It does not contain Back_Radiation, that is within the first term of the RHS.] The LHS is nearly constant. If CO2 is doubled we expect a REDUCTION of about 1W/m^2 due to increased atmospheric absorption of sunlight. On the RHS, if CO2 is doubled, there will be a decrease of Surface Energy escaping to space through the window. How much is unknown by me (it is the subject of this thread, but there does not seem to be a number being cited) but I would expect it is of similar magnitude to the change in the LHS - a DECREASE of about 1W/m^2. IF that is the case then the third term, Surface_Energy_Absorbed _into_the_Atmosphere is a constant. This term contains evaporation, conduction and net radiation, all of which are the varying quantities which Tom has identified. I make no comment on the veracity of his claims at this point, merely restating that this term must be nearly constant." Tom said: "unless you can provide a clear and succinct statement of your thesis and it relevance, I will consider it of topic and not worth the energy." I am somewhat at a loss as to how to proceed. My post is very clear, and no error has as yet been demonstrated, Tom's previous efforts having been irrelevant to the discussion as they did not address the clear statements made. For the record: 1. All the solar energy absorbed into the surface must be exported from the surface. 2. There are only two places that energy can go, either into the atmosphere or out into space. 3. The solar input is nearly constant (there is a small reduction if CO2 is increased) and we expect a small reduction in the export to space (the window slightly tightens). 4. That means that the export of energy from the surface into the atmosphere is nearly constant regardless of temperatures and CO2 concentrations There are a couple of things to note: 5. The above assumes integration over the whole surface for one year then averaging. It also assumes a planet in equilibrium with Space. 6. A constant energy flow from the surface into the atmosphere means a constant lapse rate. The lapse rate does not change with more evaporation, because any increase in evaporation is offset by decreases in energy flows from net radiation/conduction. 7. It is untrue to say that increasing CO2 increases the amount of surface energy trapped by the atmosphere. That energy entrapment is essentially constant.
    Moderator Response: (DB) Except that the energy balance at the TOA is not balanced; thefore the planet is not in equilibria in its energy budget. Your argument therefore fails this initial test.
  47. Muller Misinformation #1: confusing Mike's trick with hide the decline
    Ryan Star @147 both fails to interpret the graph @146 and presents a graph he declares to be self interpreting. To start with, the graph does not tell us which "Mornington" it provides figures for. It is produced by the Australian Bureau of Meteorology, so I shall restrict myself to Australian Morningtons. So is it from Western Australia, Tasmania, Mount Isa, Queensland, Victoria (and if so, is it figures for the Peninsular or the town?), or is it in fact for the Island. As a Queenslander (and indeed originally a north west queenslander, the Island came first to mind, with the peninsular as a close second. But I did not know while I wrote the preceding paragraph which was referred to. Checking the station number, however, I find out that it is Mornington, the town in Victoria that is referred to. Note that this checking of additional data is exactly equivalent to what is required to properly interpret the WMO graph, and which Ryan insists should not be needed. Proceeding on, the graph shows mean rainfall for given months. But is that mean daily rainfall in each month for a given year? Or is it the mean total rainfall in each month over a number of years? Well, I know a little about Victoria's weather, so I'll guess the second - but to do that I need to call on extraneous information to do so. The graph does not self interpret. Shown a similar graph for Alice Springs (for example) but without the location data, I would not be able make the judgement as to whether it was arid monthly totals, or temperate daily means for a given month. Checking the http://www.bom.gov.au/climate/averages/tables/cw_086079.shtml I can determine that my hunch was right. It was the mean monthly totals over a number of years. But that is not a given from the graph. It is only additional information that allows me to make that interpretation. Finally, over what period is it the mean? Is it over the most recent 30 years? From the establishment of the station? And if so, when was that? As it happens, I now know that it was from 1868 to 2011. But I only know that with certainty because the BOM site from which the graph was obtained draws the graph differently for other options: There are still other issues left uninterpreted here. Was the weather station always at the same location? If not, where the data adjusted to compensate for the change in station location, and if so how? Where there any issues with the station site such as overhanging branches or eaves which might have distorted the data? How frequently was the data recorded (daily, every few days, weekly), and was that consistently done? All these are relevant issues to interpreting the graph which the graph does not inform us of. So, and very clearly, the graph does not self interpret. It isn't a graph on a controversial issue so Ryan does not notice that, but it remains true. Indeed to properly interpret the graph I needed to do the same amount of sleuthing as I needed to do to interpret the WMO graph. Despite that equivalence, Ryan accuses Jones of wrongdoing, and considers the BOM graph self interpreting.
  48. Harry Seaward at 13:32 PM on 25 April 2011
    A Convention for Persons Displaced by Climate Change
    Thanks for your reply, Tom Curtis. That is an impressive bit of data analysis and compilation there! Can someone differentiate between climate refugees and environmental refugees? Also, assuming the numbers Tom C. has graciously provided are correct, what percentage of those can be attributed to AGW?
  49. CO2 effect is saturated
    novandilcosid @99 asks, ""[H]ow much additional surface energy is absorbed outside the saturated 625-725 band, ie by how much does the window close, in W/m^2? The following chart from SOD shows the change in net forcing from a doubling of CO2: The total forcing for such a doubling is, of course, 3.7 W/m^2, with the vast majority of that being in the wings. You will notice that this is the forcing at 200mb, ie the tropopause (as also for the graphs of transmitance and change in transmitance at @86 and 82 respectively. novan will of course point to the influence of the stratosphere, but that is greatly exaggerated by him, and for two reasons. First, to a reasonable approximation the energy in the stratosphere comes from UV radiation absorbed by ozone. Increasing the CO2 concentration does not increase that energy. Rather, it cools the stratosphere by radiating away that energy more efficiently. The result is a slight increase of radiation in the primary band of CO2 emissivity, but a reduction in the IR radiation by ozone (the other main gas that radiates energy away from the stratosphere). The result in zero net change in the OLR. The second effect relates to the exchange of IR energy between the top of the troposphere and the stratosphere. Increased CO2 concentration reduces IR radiation from the troposphere to the stratosphere, further cooling the stratosphere (although how strong this effect is a matter of debate). But the increased proportion of stratospheric energy radiated by CO2 means there is an increase in energy radiated from the stratosphere to the troposphere by CO2. This, however is again balanced by a reduction in the IR radiation emitted by ozone to the surface. In Line by Line and energy balance models, these effects are taken into account in determining the forcing at the tropopause. Radiative forcing is, after all, "The radiative forcing of the surface-troposphere system due to the perturbation in or the introduction of an agent (say, a change in greenhouse gas concentrations) is the change in net (down minus up) irradiance (solar plus long-wave; in Wm-2) at the tropopause AFTER allowing for stratospheric temperatures to readjust to radiative equilibrium, but with surface and tropospheric temperatures and state held fixed at the unperturbed values." Consequently the above graph of change in radiative forcing at 200 mb includes the effects of the changes in the stratosphere. Of course, novan may well dispute this, so the best thing to do is to got to empirical data. Novan's thesis is that the net effect of adding CO2 to the atmosphere is to increase radiation to space from CO2, thus cooling the Earth. (See 81 and 89 above). The following are graphs of the change in IR radiation (measured as brightness temperatures) between 1970 and 1997. Figure b top shows the change in the tropical Pacific (between 10 degrees north and 10 degrees south); while figure b bottom shows the "near global" changes (between 60 north and 60 south). The middle shows the tropical case as predicted by a model. The first think to notice is that in the CO2 emission wavelengths, the emissions are either reduced or barely increased in the tropical observations; and that for the "near global" observations and the simulation they are reduced. The second thing to notice is that the net radiation to space has increased in the tropical case (and possibly also, but slightly, in the "near global" case. This indicates an overall increase in temperature of the Earth/atmosphere system in 1997 relative to 1970 which is anomalously large compared to that expected by the GHE alone. The obvious reason for this is the 1997/1998 El Nino which commenced in April of 1997 (the data is for the April-June period). The obvious thing to do is to remove the temperature effects from the record. Doing so reveals graph C in the figure (and figure 1 in the article above) which shows a clear reduction radiation in the CO2 band. Thus novan's thesis is clearly refuted by the observational data.
  50. Muller Misinformation #1: confusing Mike's trick with hide the decline
    Les what is the non sequitur nil point? John Cook writes that Mr Jones "has been rightly criticised for failing to distinguish between reconstructed temperature and the instrumental temperature in a graph." I ask, do you agree? Why is it so hard getting straight answers (or any answer) to straight questions around here?
    Moderator Response: [DB] The specific text from the original post does NOT say that Jones was being criticized, but rather: "This technique has been rightly criticised for failing to distinguish between reconstructed temperature and the instrumental temperature in a graph." (emphasis added) Perhaps the lack of clarity and the holiday weekend have a lot to do with the lack of response.

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