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Comments 87301 to 87350:

87301. RyanStarr at 12:22 PM on 25 April 2011
       Antarctica is gaining ice
       No that isn't the entire basis of the argument DSL, far from it. The point is the article attempts to draw climatic trends from periods of under 10 years. Do you think this is an adequate length of time DSL? If we take the claims of the article as truth and extrapolate back over the past century of warming do we obtain a result which is backed up by real world observation for that period? ("mostly steady", the anomaly today sits where it started 12 years ago, yes mostly steady)
87302. Eric (skeptic) at 11:52 AM on 25 April 2011
       Cosmic ray contribution to global warming negligible
       I don't have a scientific paper showing why that particular upward excursion did not cause "even more cooling" during an ice age, but more low clouds in an ice age may not be as cooling as more low clouds in temperate period. For one thing with less moisture in the ice age, there is less of an increase in the water cycle and thus less cooling effect than in interglacials. But I also know that GCR are not always a well correlated factor with climate despite the papers I previously linked. Their effect is highly nonlinear and can be coincident with other solar effects that may be the cause that GCR might get credit for. The geomagnetic excursions that you point out are often terrestrial and thus remove the other solar factors from consideration. That would support more climate effect from solar factors other than the solar modulation of GCR. But that doesn't mean that GCR have no effect, just not a monotonic effect like a solar or GHG forcing.
87303. Tom Curtis at 11:42 AM on 25 April 2011
       CO2 effect is saturated
       novandilcosid @104, I am dropping the debate about the relation between evaporative energy transfers and net radiation. It is too time consuming, and so far as I can tell almost irrelevant to this topic. Indeed the only relevance I can see to global warming is that if your theory were true, the Green House Effect would be stronger than it is currently predicted to be. That is because if the energy flow to the atmosphere were constant with temperature, the energy flow from the atmosphere to space must also be constant with constant insolation regardless of surface temperature. Therefore any adjustment to reduced outgoing radiation due to green house gases must be entirely compensated for by changes in surface temperature, rather than partly compensated for by increased atmospheric temperatures as currently believed. So, 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.
       Moderator Response: [DB] Fixed closing bold tag.
87304. Tom Curtis at 10:57 AM on 25 April 2011
       A Flanner in the Works for Snow and Ice
       More usefully, the average annual temperature anomaly between the 80's and the 2000's for the area from 67 degrees north to the pole is 1.2832875654 degrees C. The formula the (sum of temperature times area for each latitude band) divided by the area of the entire spherical cap, with areas for latitude bands and spherical cap determined by the formula given by Sphaerica @115, using a radius for the Earth of 6371 km. As the Earth is an oblate spheroid, that will have introduced some error, but inconsequential for our purposes.
       Moderator Response: [DB] Fixed equation result.
87305. muoncounter at 10:55 AM on 25 April 2011
       Cosmic ray contribution to global warming negligible
       Eric#18: "a cloud modulation factor in the middle of a cold dry ice age." Ice ages aren't quite that monolithic. For ice sheets to grow, it must snow and thus there must be clouds. The figure Alexandre posts in #17 shows a large GCR change, on the scale of 1000 years during a geomagnetic excursion. There is no corresponding climate change in the oxygen isotope graph.
87306. novandilcosid at 10:47 AM on 25 April 2011
       CO2 effect is saturated
       Tom Curtis also wrote @#103: " it also make debate with you pointless and uninteresting. I will merely note that keeping your discussion factual seems a low priority to you." I expect that Tom would like to withdraw this remark. I hope that my two previous posts have in fact answered his criticisms in detail. If not, perhaps he would be so kind as to point out where not.
87307. novandilcosid at 10:36 AM on 25 April 2011
       CO2 effect is saturated
       Tom Curtis wrote @#103 above: "Further, you indicate that both constant RHS with a 2.5% increase in evaporation per degree C and a decreasing RHS with a 5% increase in evaporation per degree C are reasonable suppositions. However, both suggest decreases in the value of the non evaporative terms on the RHS, and the second suggests a much larger decrease." Tom is correct. The terms within the term "Surface_Energy_Absorbed _into_the_Atmosphere" are Net_Radiation, Evaporation and Conduction. It is known that evaporation INCREASES with temperature. All authorities agree on that. What is not known is by how much. Is it 2.5% (models), 5% (measurement), or 6.5% (Clausius-Clapeyron, assuming constant RH ) per DegC? It is also known that Net_Radiation INCREASES with temperature. But it DECREASES with increased CO2 concentration (back radiation increases slightly as the average altitude from which CO2 earth-bound photons are emitted drops. This level is lower therefore warmer, so there is aqn increase in intensity.)
87308. Eric (skeptic) at 10:35 AM on 25 April 2011
       Cosmic ray contribution to global warming negligible
       #17, I would not expect much of an effect from a cloud modulation factor in the middle of a cold dry ice age. We would not expect the climate to get colder from an increase in cosmic rays since the hypothesized cooling mechanism relies on water vapor. OTOH, there is a bit of cosmic ray to climate correlation over the MWP to LIA http://spaceweb.oulu.fi/~kalevi/publications/Usoskin_etal_JGR_2005.pdf but more on a 100's of millions of years timescale: http://www.juniata.edu/projects/oceans/GL111/celestialdriverofclimate.pdf
87309. novandilcosid at 10:24 AM on 25 April 2011
       CO2 effect is saturated
       Tom Curtis wrote @103 above: "in 97 I identified several factors on the RHS of the equation that result in changes in value on the LHS, specifically, in changes to the back radiation." I think Tom is referring to a different equation to the one I have been using to establish that the Surface Energy absorbed by the atmosphere is nearly a constant, regardless of CO2 concentration or temperature. Naturally this would cause differences of opinion to arise! I have ignored Tom's interesting observations simply because they are not relevant to the case - they amount to identifying variations in terms on the RHS of the equation, and these variations do not affect the hypothesis. The equation I have been using is: 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 writes: "You chose to ignore that facts I have raised, and simply re-assert your position." I agree. I have ignored his points (this is not to say I don't find them interesting), as I believe them to be irrelevant to the point I have been making. The Surface Energy absorbed by the atmosphere is nearly constant, regardless of surface temperature or atmospheric CO2 content. The degree of saturation is central to this assertion.
87310. Alexandre at 09:04 AM on 25 April 2011
       Cosmic ray contribution to global warming negligible
       There's this graph Richard Alley uses in his "Biggest Knob" lecture showing a great excursion of cosmic rays during the Laschamp Event, and no visible corresponding variation of temperature. From Muscheler et al. 2005 "Geomagnetic field intensity during the last 60,000 years based on 10Be and 36Cl from the Summit ice cores and 14C" I think it's quite a striking image, and it illustrates the amplitude limitations of this possible cosmic ray influence.
87311. Andy Skuce at 08:18 AM on 25 April 2011
       Wakening the Kraken
       There's a useful article on the global warming potential (GWP) of methane relative to the same mass of CO2 here. Below is a figure from that article showing the decline in GWP plotted against the time since emission.
87312. DSL at 06:58 AM on 25 April 2011
       Antarctica is gaining ice
       Doesn't work, Ryan. You need to look at ocean temps as well when discussing polar changes. The entire basis of your argument is wrong, so this is addressing your main point. That's a pretty big jump from the Spencer-interpreted UAH LT "mostly steady" (not really) to "the climate isn't changing." There is overwhelming (as in too many studies to keep track of) evidence that the climate is changing rapidly, whatever the cause. The Arctic sea ice anomaly is nose-diving, and the global glacier mass balance is diving even more sharply.
87313. Philippe Chantreau at 04:40 AM on 25 April 2011
       Cosmic ray contribution to global warming negligible
       The CR hypothesis is so tenuous as to be irrelevant. There is no known physical process that can lead the ionized particles to the size necessary to act as condensation nuclei. The CERN experiment has yet to deliver anything useful. The so-called correlation with Forbush events seen by Svensmark over the Pacific included several days of delay, during which air masses move and all sorts of other things can happen. The CR thing literally amounts to grasping at straws.
87314. Bob Lacatena at 04:34 AM on 25 April 2011
       A Flanner in the Works for Snow and Ice
       114, RW1,

       ...how do we get the surface area weighted averages?

       I believe the equation for the surface area between two latitudes is

       2πr² [ (1 - sin(L₁) - (1 - sin(L₂) ]

       where

       r = radius of the Earth L₁ = the lower latitude (closer to the equator) L₂ = the higher latitude (further from the equator)

87315. JMurphy at 04:34 AM on 25 April 2011
       Lindzen Illusion #1: We Should Have Seen More Warming
       rhjames, to provide your evidence of how the IPCC "deliberately misrepresented scientific evidence", please choose one of the IPCC-related threads here, here, here, or here. Don't forget to read the headline post and all comments, just in case you repeat something which has already been discussed. After having done that, if you still feel confident that you have something new to add (especially with regard to 'deliberate misrepresentation'), please do so. Otherwise, you have the opportunity to withdraw your accusation.
87316. RW1 at 04:16 AM on 25 April 2011
       A Flanner in the Works for Snow and Ice
       Tom Curtis (RE: 113), 1980 compared to 2010: 67.00000000 1.433453083 69.00000000 1.605143428 71.00000000 1.782773018 73.00000000 1.956291556 75.00000000 2.163378954 77.00000000 2.532876968 79.00000000 2.804517508 81.00000000 2.930059433 83.00000000 3.353630066 85.00000000 3.353630066 87.00000000 3.353630066 89.00000000 3.353630066 or 1980-1990 compared to 2000-2010: 67.00000000 1.022729039 69.00000000 1.085630417 71.00000000 1.143316746 73.00000000 1.204136610 75.00000000 1.295737386 77.00000000 1.443844914 79.00000000 1.538919687 81.00000000 1.585246086 83.00000000 1.786555529 85.00000000 1.786555529 87.00000000 1.786555529 89.00000000 1.786555529 Assuming these figures are accurate, how do we get the surface area weighted averages?
87317. les at 03:54 AM on 25 April 2011
       Muller Misinformation #1: confusing Mike's trick with hide the decline
       Damn! My french witticisms don't work, given the mods (snips) Editors, hu? Can't publish without them, Can't publish with them.
87318. les at 03:37 AM on 25 April 2011
       Muller Misinformation #1: confusing Mike's trick with hide the decline
       149 No one is saying that a graph shouldn't be clear, that's just silly; but they do have to be read in context to convey scientific content - as your example shows. Your second point is a non sequitur nil point.
87319. RyanStarr at 03:30 AM on 25 April 2011
       Muller Misinformation #1: confusing Mike's trick with hide the decline
       Les, you're right graphs are not data, they display data. That's obvious right? And they should be labeled such that the reader knows what is displayed. You guys might need to read the article above again, it isn't a total whitewash of what was done and does contain the following quote, "This technique has been rightly criticised for failing to distinguish between reconstructed temperature and the instrumental temperature in a graph." Or do you two disagree with John Cook that the criticism in that case was rightful?
87320. les at 03:30 AM on 25 April 2011
       Muller Misinformation #1: confusing Mike's trick with hide the decline
       147 - to easy. The answer is < fake French accent ON > "ze mean? over what time period ees dis mean calculated?" < fake French accent OFF > What do I win? Joking aside, it really is very very clear that graphs go with analysis. There really is no argument about that.
87321. RyanStarr at 03:09 AM on 25 April 2011
       Muller Misinformation #1: confusing Mike's trick with hide the decline
       Logic isn't your strong suit is it Tom? Graphs can be self-interpreting, hence this one must be. { -snip - } You said "no chart is self interpreting." Really? { - snip -} Note that this contains less information than Jones had on his WMO chart.
       Moderator Response: [muoncounter] Less attitude, more science. Read the Comments Policy.
87322. Tom Curtis at 02:51 AM on 25 April 2011
       A Flanner in the Works for Snow and Ice
       RW1@113: [Source] The zonal means from 59 degrees north are: 59.00000000 0.9049376845 61.00000000 0.9578167200 63.00000000 1.027678609 65.00000000 1.094777465 67.00000000 1.213630080 69.00000000 1.325709581 71.00000000 1.454651952 73.00000000 1.595859289 75.00000000 1.811631322 77.00000000 2.137880087 79.00000000 2.348255634 81.00000000 2.444648981 83.00000000 2.764386654 85.00000000 2.764386654 87.00000000 2.764386654 89.00000000 2.764386654 Your can work out the actual mean for from 65 degrees (or 67 degrees) north by weighting each latitude band for area; or you can work on the obvious fact that mean increase in temperature within the arctic circle is obviously greater than 1 degree over this period.
       Moderator Response: [DB] Fixed images.
87323. RyanStarr at 02:31 AM on 25 April 2011
       Antarctica is gaining ice
       OK lets substitute lower atmoshphere for surface temperature, that's what the satellite measures http://www.drroyspencer.com/wp-content/uploads/UAH_LT_1979_thru_Mar_2011.gif Is that an acceptable source DSL? Can we address the main points made which this isn't?
87324. RW1 at 02:28 AM on 25 April 2011
       A Flanner in the Works for Snow and Ice
       muoncounter (RE: 110), "Why not start on the observation side, rather than an with an 'if'?" Cause and effect. The graph seems to show about 0.75 C of warming from 1980 to 2003 from 60-75˚, but what about 66.6˚ to the North pole from 1979 to 2010?
87325. Tom Curtis at 01:58 AM on 25 April 2011
       A Flanner in the Works for Snow and Ice
       Ken Lambert @109, from spreadsheet described in my 73, as modified to include actual arctic sea ice extents as described in my 88.
87326. muoncounter at 00:58 AM on 25 April 2011
       A Flanner in the Works for Snow and Ice
       RW1 #108: "to see if it was enough to melt the ice." Why not start on the observation side, rather than with an 'if'? Observed: Arctic ice melting (see any of the many threads here at SkS, along with copious literature). Observed: Warming (graph posted above); if that's not good enough, Comiso 2003 is a good read. Average temperature trends are generally positive at 0.33 +/-0.16C /decade over sea ice, 0.50 +/-0.22C / decade over Eurasia, and 1.06 +/-0.22C / decade over North America. The trend is slightly negative and insignificant at -0.09 +/- 0.25C/decade in Greenland with the negatives mainly at high elevations. Conclusion: There must be enough of a radiative forcing imbalance in the Arctic so that both ice extent is decreasing (and melt season getting longer) and temperatures are warming at rates much greater than the global average. Perhaps you can calculate whether all of this can occur with 0 net forcing. That would evaluate 'natural cycles.' But I'm reminded of a talk by Ken Wilson, a Nobel laureate in Physics, several years ago: He stated the memorable line: 'I don't mind reinventing the wheel, I just don't like reinventing the flat tire.'
87327. Tom Curtis at 00:52 AM on 25 April 2011
       CO2 effect is saturated
       novandilcosid @100, in 97 I identified several factors on the RHS of the equation that result in changes in value on the LHS, specifically, in changes to the back radiation. I also identified factors which cause relative changes to the value of the terms on the RHS of the equation. As your argument requires that the LHS determine the value the values on the LHS, but not in turn have their values determined by factors on the RHS, your argument fails because the value of back radiation has been shown to be partially dependent on RHS factors. Further, your argument also depends on the two non-evaporative values on the RHS being constant, and this has also been shown to be false. You chose to ignore that facts I have raised, and simply re-assert your position. Fine - that it your right, but it also make debate with you pointless and uninteresting. I will merely note that keeping your discussion factual seems a low priority to you. Curiously, not only are you uninterested in trying to grapple with the facts I presented, you then go on to refute your own case. First, you indicate that rate of evaporation per degree C is not known, but according to you that value follows by straightforward reasoning from the energy balance equation. Further, you indicate that both constant RHS with a 2.5% increase in evaporation per degree C and a decreasing RHS with a 5% increase in evaporation per degree C are reasonable suppositions. However, both suggest decreases in the value of the non evaporative terms on the RHS, and the second suggests a much larger decrease. These are terms you require to be constant which changing temperature for your argument to succeed, but now you entertain the notion that they are anything but.
87328. Ken Lambert at 00:34 AM on 25 April 2011
       A Flanner in the Works for Snow and Ice
       Tom Curtis Where did you get these numbers? 1979-1983: -7.40E+020 Joules 1984-1988: -4.18E+020 Joules 1989-1993: 8.24E+020 Joules 1994-1998: 1.41E+021 Joules 1999-2003: 2.06E+021 Joules 2004-2008: 6.97E+021 Joules
87329. Tom Curtis at 00:19 AM on 25 April 2011
       A Convention for Persons Displaced by Climate Change
       Harry Seaward @59, the number of environmental refugees has been extensively referenced in previous posts. The population data comes from wikipedia and other sources for the 1% per annum global growth. Regional growth is determined from this chart: 1.02^10 = 1.219, and 1.025^10 = 1.28 , or a 21.9% and 28% growth over 10 years respectively. That compares with the 26.1% growth over 10 years in Africa, or 26.8% for Nigeria. I determined population growth from 1995 by taking 1.03^(Year-1995). That should safely overestimate growth rates, and hence underestimate the growth in environmentally displaced people that cannot be accounted for by population growth.
87330. RW1 at 23:46 PM on 24 April 2011
       A Flanner in the Works for Snow and Ice
       muoncounter (RE: 106), "Why only two years?" I would like to know how much the Arctic has warmed from 1979 to 2010. From that, see if it was enough to melt the ice.
       Moderator Response: [DB] Did you read the article that is the subject of this post?
87331. poptart at 23:24 PM on 24 April 2011
       A Flanner in the Works for Snow and Ice
       I'm pretty sure that if we just choose to ignore the actual evidence, the problem will go away!
87332. muoncounter at 22:53 PM on 24 April 2011
       Cosmic ray contribution to global warming negligible
       A series of FDs began on March 18. Maybe that's what is causing the Texas wildfires! Correlation, no? Why are the CR -> clouds folks not screaming about aircraft contrails? Stordal et al 2005: found indications that cirrus cloud amount increases have accompanied an increase in air traffic in the 16 year period 1984–1999 ... Our mean estimate of the radiative forcing (0.03 Wm⁻²) is close to the number given in the IPCC (1999) (upper limit in their assessment is 0.04 Wm⁻²) Wait ... these high, thin clouds are a positive forcing, slowing the escape of radiant energy to space. Airplane flight is definitely not a 'natural cycle.' Doesn't that spell anthropogenic global warming? Is that why we don't hear about contrails, but we do hear about the ephemera that is the supposed cosmic ray-climate change connection?
87333. dhogaza at 22:36 PM on 24 April 2011
       Cosmic ray contribution to global warming negligible
       RHJames: "If I simply stand outside and feel the difference between full sun, and cloud, and just feel the difference in energy reaching Earth's surface, I can't help thinking this is what it's all about." This explains why sunny Bismark North Dakota is so much warmer in winter than cloudy Portland Oregon ...
87334. SNRatio at 20:34 PM on 24 April 2011
       Cosmic ray contribution to global warming negligible
       Fig 1: Is the estimated cloud cover variance, given CR intensity, constant?
87335. Michael.M at 20:31 PM on 24 April 2011
       Cosmic ray contribution to global warming negligible
       Correlation is not Causation! How often have we heard this tiresome meme in discussions of CO2 and Greenhouse-Effect, despite of strong theoretical and experimental based physics "how" the GHE works? And now the pseudo-sceptics dismiss all of their "scepticism" and we have to dicuss a slightly correlation that "somehow" affects cloud cover! It shows a typical pseudo-sceptic tactics: Take a point with known uncertainties, claim something nearly (but not completely) unsubstantiated, and blow it out of proportion to explain why anything but CO2 is causing Global Warming.
87336. Paul D at 20:13 PM on 24 April 2011
       Cosmic ray contribution to global warming negligible
       RHJames: "If I simply stand outside and feel the difference between full sun, and cloud, and just feel the difference in energy reaching Earth's surface, I can't help thinking this is what it's all about." Well if you want to appeal to the (somewhat unscientific) mind of the common person on the street, then simple thoughts like that will appeal to many. Which suggests you aren't interested in education, rather you are appealing to a persons ignorance. In order to gain credibility skeptics need to express some consistency, that means not claiming that the climate system is to chaotic and complex on one hand, whilst at the same time suggesting simplistic answers will reveal the truth.
87337. SNRatio at 19:05 PM on 24 April 2011
       Cosmic ray contribution to global warming negligible
       I think we may have yet another illustration of the difference between weather and climate here. While there seems to be some evidence indicating cosmic ray influence on cloud formation and, eventually, rainfall, the net long term effect on climate may still be negligible. In any case, it is small contributions, and if they mostly cancel out, as will very often be the case, the net effect will be close to zero. Clouds will often typically tend to have these kinds of net-zero-effects: As Ari J mentions, increasing albedo, and shielding outgoing radiation, for example. They may, however, not cancel out, and then the net effect may become much larger. Svensmark and other proponents have, however, not been able to demonstrate such effects, and at the same time guard against competing explanations. To me, omitting or skewing the discussion of competing models (arch s, #3) is rather telling. If we, for good measure, multiply the Erlykin estimate of temperature increase by 10, we get about as much warming as has occurred in one year recently. "Yep, it might account for one of 50 years of warming. What about the other 49?"
87338. novandilcosid at 18:31 PM on 24 April 2011
       CO2 effect is saturated
       In the headline post (advanced version) the author assumes a "final layer" which is a black body at 220DegK. I have three objections to this: 1. The "Final Layer" is nothing of the sort. Photons are emitted at all levels. Absorption ensures that most never make it out to space through the fog of overlying gas. The average emission height is determined by absorption. In general this level will be different for every frequency. 2. The atmospheric gases are not black bodies - nothing like black bodies. Unlike solids or liquids they do not emit a continuous spectrum, but preferred frequencies (lines), the envelopes of which both in detail abnd as a conglomerate are far from a black body. See http://spectralcalc.com/spectral_browser/db_intensity.php. A black body curve is not appropriate and the "blackbody temperature" cannot be used to estimate the average height of emission. 3. It is implied that the amount of energy absorbed is the difference between two blackbody curves. This is an erroneous view. Energy absorbed into the atmosphere is ALWAYS manifested as kinetic energy (atmospheric heat) at the point of absorption. That energy flows upward by convection and radiation, still manifested as kinetic energy. It is then radiated to Space by the GHGs, primarily Water Vapour, with a little from CO2 (15-18W/m^2) and Ozone. These GHG molecules are energised by collision with other air molecules (around 50 times per nanosecond) and if the energies are right and the star signs are right (ie around one chance in one hundred thousand) a photon is emitted at a preferred frequency. If that photon avoids absorption by other GHG molecules, it escapes to space and that energy is lost from the planet.
87339. adelady at 18:10 PM on 24 April 2011
       Cosmic ray contribution to global warming negligible
       rhj - you must live somewhere very unlike my experience. We find here that if the day is chilly, clouds moving in can make it noticeably warmer/ milder. This goes double for after dark. (And it's often the sign of rain on the way.)
87340. Ari Jokimäki at 17:48 PM on 24 April 2011
       Cosmic ray contribution to global warming negligible
       Then on the other hand, in northern winter clouds warm the weather considerably. Also, clouds warm everywhere during night-time. This is because clouds also have greenhouse effect in addition to their ability to reflect sunlight. Due to greenhouse effect, high clouds cause more warming by absorbing thermal radiation than cooling by reflecting sunlight. Clouds don't just cool. Also, more clouds doesn't necessarily mean more cooling.
87341. novandilcosid at 17:43 PM on 24 April 2011
       CO2 effect is saturated
       Tom Curtis @#97 disputes that the heat transport from the surface into the atmosphere is almost a constant whatever the surface temperature. He cites: Increased wind due to increased temperature. Changed Lapse Rate. Change in surface emissivity. Change in conductivity of the air due to higher moisture content. These may all be true [I actually dispute Lapse Rate changes: the lapse rate is controlled by the total energy into the atmosphere - net radiation, condensation of water, conduction, which I claim is virtually constant. So the Lapse Rate is a constant and Lapse Rate feedback may be a furphy.] but the LHS of the equation is always the sunlight absorbed by the Surface. Unless the albedo or solar constant change, sunlight absorbed by the Surface is invariant. On the RHS we have: Surface Energy absorbed into the atmosphere (NET radiation, condensed water vapour, conduction) plus Surface Energy radiated direct to space through the window. This latter term is nearly a constant, particularly if CO2 is nearly saturated (which it seems to be. It might change by a few percent if CO2 doubles - I look forward to calculated values for a doubling of CO2). If CO2 doubles we know that the LHS decreases by approximately 1W/m^2 (increased absorption of sunlight by CO2 in the upper atmosphere). This will approximately balance any decrease in Surface radiation through the window, so the Surface Energy absorbed by the atmosphere will remain the same.
87342. rhjames at 17:39 PM on 24 April 2011
       Cosmic ray contribution to global warming negligible
       delady "rhj, and when you're outside on a clear, frosty morning do you notice the difference when cloud cover moves in? I notice that it gets a bit less nippy at those times." Certainly - I can ski in a T shirt in full sun, but when the clouds come over, it's back on with the parka. That's a huge change in energy reaching me.
87343. novandilcosid at 16:35 PM on 24 April 2011
       CO2 effect is saturated
       Tom Curtis responded in #97 to my statement that surface energy into the atmosphere is essentially constant. "Specifically, you insist that an increase in temperature will result in an increase evaporation" Too right! We recall that the statement is only true when the energy flows are integrated over the entire surface over an entire year, then averaged. A second stipulation is that the system is in equilibrium - there are no net inflows or outflows. This is essentially what Kiehl & Trenberth say in their 1997 diagram, and is also implied by any statement that "the average temperature of the planet will increase by X degrees." While the statement will not be true at specific locations, it is true for the planet as a whole (remembering that 70% is water). [Off topic: The amount of increase in evaporation per DegC is disputed (see for example Schneider, Gorman and Levine, 2009, http://arxiv.org/abs/0908.4410 ). It is also unknown if relative humidity changes. The modellers assume constant RH (no better estimate), Clausius-Clapeyron water vapour increase (6.5%/DegC) and around 2.5%/DegC for evaporation. Actual measurements suggest that RH has decreased with increasing temperature, and that the rate of evaporation increase is 5%/DegC. Essentially the water properties of the atmosphere are unsettled science. Many climate scientists disagree with the assumptions in the models.]
87344. novandilcosid at 16:14 PM on 24 April 2011
       CO2 effect is saturated
       Tom Curtis @ #94 wrote: " But those same figures above clearly show that there is a substantial reduction in radiation to leaving the troposphere outside those that range, but between 500 and 850 cm^-1. " The most active region is the band between 625 and 725. (See http://spectralcalc.com/spectral_browser/db_intensity.php) The lines here are around two orders of magnitude greater intensity than the lines in the rest of the band. 1. The question relevant to saturation is how much additional surface energy is absorbed outside the saturated 625-725 band, ie by how much does the window close, in W/m^2? I have always assumed that this is small - not more than 0.5W/m^2 for a doubling of CO2. 2. At the top of the atmosphere, what is the emission strength from CO2 in these weak parts of the band? The 625-725 region is emitting about 15-18W/m^2 (see plots of outgoing radiation measured in space eg http://acmg.seas.harvard.edu/people/faculty/djj/book/bookhwk7-1.gif http://www.mathstat.dal.ca/~folkins/Cloud-LWspectrum.jpg . http://climateaudit.org/2008/01/08/sir-john-houghton-on-the-enhanced-greenhouse-effect/ ). The much weaker lines outside this region won't be emitting much. So I guess I'd like to see some calculation of both these effects in the weak band to see if it is relevant. If the powers are small then this part of the band can be ignored, even though the majority of the emissions from them are plainly from below the Tropopause.
87345. novandilcosid at 15:52 PM on 24 April 2011
       CO2 effect is saturated
       Tom Curtis @#94 wrote: "the range 630 to 710 cm^-1 come from the stratosphere. (I am not agreeing, I am just not disputing.) Certainly it comes from high enough that, as shown in 82 and 86 above, that increasing CO2 concentrations make no difference to the amount of radiation escaping from the troposphere at those wave numbers, which is all that is relevant to this discussion. But those same figures above clearly show that there is a substantial reduction in radiation to leaving the troposphere outside those that range, but between 500 and 850 cm^-1. 1. I dispute that there is no change in energy radiated from the troposphere. I think the figures in #82,86 are NOT sufficient to estimate what happens: they are disclosing the opacity of the atmosphere as seen from the ground. This is not helpful when trying to determine what the effects are in the region which is already 100% opaque. It seems obvious that for the level in the atmosphere at which 20% of the photons make it through the CO2 fog to outer space, a doubling of the thickness of the fog will move the 20% emission layer higher. 2. The $64 question is where are the photons coming from in the very active 625-700 region with CO2 at 380ppm? My calculations suggest only 10% are coming from below the Tropopause, the remainder from above. If that is the case, then for this band a doubling of CO2 will mean emissions from higher in the stratosphere. The net effect in this band will therefore be an INCREASE in power radiated to space.
87346. Ari Jokimäki at 14:59 PM on 24 April 2011
       Cosmic ray contribution to global warming negligible
       muoncounter: "It's not clear what you're saying here: are these cloud cover decreases due to lower CR flux? Svensmark et al 2009 make this quixotic remark:" I might have simplified the situation bit too much there. Erlykin et al. say: "The well-known Forbush Decreases in CR intensity (denoted‘FD’ and typically 3% for 2 or 3 days) caused by changes in the solar wind - and attendant CR modulation - following solar ‘eruptions’, should, if the CC, CR correlation is causal, give rise to CC reductions. Indeed, even if not causal but if both CR and CC changes are due to a third variable (solar irradiance, for example) then a correlation should result. Svensmark et al. (2009) have claimed such a correlation for CR FD and the liquid cloud fraction (LCF), but this has been disputed (by us, Laken et al.,2009 and by Calogovic et al.,2010)." muoncounter: "Who did this analysis? Again, which way are the changes?" Laken et al. (2010). muoncounter: "Do they claim any significance to this decrease?" They refer to Bazilevskaya et al. (2008) and to be more precise, they say that the decrease has been "less than 0.6 %". muoncounter: "Isn't this the best take-away? The contribution of CR to ‘climate change’ is quite negligible." Erlykin et al. conclude: "The increase in temperature predicted is 0.002°C, a value quite negligible in comparison with the Global Warming in this period (~ 0.5°C) and the conclusion is that cosmic rays have a negligible effect on climate."
87347. muoncounter at 14:30 PM on 24 April 2011
       A Flanner in the Works for Snow and Ice
       RW1 #105: "data from 1979 and 2010." Why only two years? -- from here
87348. RW1 at 14:06 PM on 24 April 2011
       A Flanner in the Works for Snow and Ice
       I need data from 1979 and 2010. How much has the Artic warmed?
87349. Aardvark at 13:52 PM on 24 April 2011
       Has sea level rise accelerated since 1880?
       I posted this originally to Tamino's blog, but it didn't show up for some reason. So I am reposting it here The reason Houston and Dean are using a quadratic fit is that they are trying to ascertain the long term average rate of acceleration. They note that Douglas (1992) has determined that it is necessary to analyze upwards of 50-60 years of continuous data in order to determine a significant trend, because decadal scale oscillations in the acceleration are common in the observed record. By significant I do not mean “statistically” significant: rather, I mean significant with respect to the determination of the type of long term trend that the climate models forecast in response to the increase in atmospheric greenhouse gases. If we had thousands of years of data, this could be done by first decomposing the data with a Fourier series analysis, and then analyzing the low frequency signals for statistics on acceleration. But we don’t have enough data to do that, so the next best thing is to fit the data to a quadratic curve, which by definition yields the “average” acceleration rate of the entire sample space. Houston and Dean are explicit with respect to their reasons for starting the analysis at 1930. Quoting from the paper: “A review paper on sea-level acceleration by Woodworth et al. (2009) notes that the analysis by Church and White (2006) shows a positive acceleration, or ‘‘inflexion’’ point, around 1920–30. They do not use the mathematical definition of an inflexion point as the point where the curvature (second derivative) changes, but instead define it as a change in sea level trend. They say that the inflexion point around 1920–30 is the main contributor to acceleration from 1870 to 2004. Woodworth et al. (2009) concluded there was consensus among the authors that acceleration occurred from around 1870 to the end of the 20th century; however, with the major acceleration occurring prior to 1930, the sea-level rise (Figure 1) appears approximately linear from 1930 to 2004. Church and White (2006) did not separately analyze this specific period.” So, Houston and Dean analyze from 1930 forward to determine if the acceleration is a persistent (long term) trend or not. If the acceleration is a response to atmospheric greenhouse gas emissions, the trend should in theory be persistent and observable in the record since 1930. Tamino's method of analysis consists of averaging over shorter and shorter time scales as one moves along the time axis. This effectively weights higher frequency signals more and more as one approaches the present time. This method ensures that such a plot will look more “active” on the right hand side of the plot.(i.e. the left hand side of such a plot will always have less high frequency events than the right hand side) Since the most recent data indicate a short term increase in acceleration , this ensures that Tamino's plot will appear to show this acceleration as if it were a novel event, which is misleading. Houston and Dean acknowledge that there is a recent trend showing increased acceleration, especially evident in the satellite altimetry data. They discuss this observation at length. They conclude that this type of higher frequency event is not unique in the observational record, and that although it may represent a long-term change in the rate of acceleration, it is not possible to determine this with the limited amount of data available (again, 50-60 years of data is needed) They speculate that it is more likely just another decadal oscillation ,for several reasons they give in the paper, but they do not form any definite conclusions on this point. The Houston and Dean analysis is appropriate for use in determining the long term trend of acceleration in the 20th century (at least since 1930) . Whether this is important information or not depends on the results of the hindcasting verification runs of the climate models . If the climate models hindcast a significant positive 20th century long-term acceleration, and if, as Houston and Dean demonstrate, such an acceleration is not present in the observational record, it gives good reason to be concerned that the process descriptions that govern the models are in error. I don’t know enough about the climate models to know what their hindcasts indicate, so I can’t asses the relative significance of these results with respect to climate modeling.
87350. Harry Seaward at 13:26 PM on 24 April 2011
       A Convention for Persons Displaced by Climate Change
       Tom @ 57 Where are you getting your data from? Please reference.

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