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Comments 81051 to 81100:

81051. Camburn at 07:32 AM on 28 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Go to the NOAA link, go to page 28: "The CFS.v1 ensemble mean (black dashed line) predicts La Nina conditions by late Northern Hemisphere Fall 2011."
81052. Patrick 027 at 07:32 AM on 28 June 2011
       The Planetary Greenhouse Engine Revisited
       Re Michele 42 - Heating of the thermosphere has nothing to do with avoiding runaway. Take away solar heating of the thermosphere. What happens? The thermosphere gets colder. Actually there'd be less downward heat flux due to that, so there would be a cooling effect below, too. But not much, because it's a very, very, very, very small amount of flux involved in maintaining the thermospheric temperature. Clarifying my earlier point: Take away the ozone layer and the upper stratosphere and lower mesosphere get colder. That's pretty much it. There isn't much change to the troposphere; except there is some added warming effect because some portion of the solar heating of the ozone layer is now solar heating below the tropopause (warming effect for the surface and troposphere - small, nothing that would get you anywhere at all near Venus, not even close, not even remotely), while the downward LW flux from the ozone layer is also gone (cooling effect - reduces the greenhouse effect). - The cooling effect is both from the loss of a greenhouse gas, and from the reduced temperature of that part of the upper atmosphere, which would reduce the downwared LW flux at the tropopause. We can focus on the effect of solar heating by considering what happens if ozone's UV absorption is eliminated while retaining the greenhouse properties of ozone; in that case, the cooling effect on the troposphere from the reduced LW flux from the cooler upper atmosphere remains, as does the warming effect of increased UV heating below the troposphere; setting aside any effects on/of UV albedo, the warming effect would be greater because the reduction in net LW cooling of the ozone layer is only equal to the reduction in solar heating there, which is equal to the increased solar heating of the surface+troposphere, while the cooling effect can only be some fraction of the reduced LW flux out of the ozone layer. But this is a matter of ~ 10 W/m2; if solar heating below the tropopause increased by 10 W/m2 and the downward LW flux at the tropopause decreased by 5 W/m2, then the forcing would be a bit more than that of a doubling of CO2, so you'd get between 1 and 2 K warming without compositional feedbacks, and with feedbacks (as in Charney sensitivity, not getting into ice sheets and some other things), that may be a bit over 4 K, give or take. It's no Venus territory. More on that at the end of this... Emission to space is occuring from both the colder and warmer levels; it increases going upward because of less optical thickness above. Otherwise it is actually more from the warmer levels than colder levels because emission rates increase with increasing temperature (Planck function). Think about it - at any frequency, the fraction of radiation emitted at some level that escapes to space always increases going upward. This will tend to be true for the whole LW spectrum, unless there is a sufficient change in spectral properties with height. If radiation is emitted from CO2 at the tropopause to space then surely it is emitted from the CO2 in the stratopause, and except for line broadenning and line strength variations, the CO2 in the stratopause is emitting more radiation, per unit CO2, than either the CO2 at the tropopause or mesopause. -------------- Yes in an EM radiating field. Not at all for the processes based on the collisions among the molecules as heat->EM and vice versa. But all the processes that do occur, including those which excite or relax a molecule so that it may emit a photon or so that it may not emit a photon after just absorbing one, are occuring in any sufficient population of molecules with sufficient collisional frequency. At LTE among the non-photons, which can be approximately maintained by sufficient collisional frequency, the distribution of energy among states is such that the fraction of molecules with some probability of absorbing any incident photons and the fraction that will emit photons in a given time period fit the temperature of the material, and it will emit according to the Planck function and absorb according to incident radiation and do both according to the same absorption/emission spectrum. Spontaneous emission occurs. Absorption also occurs when photons are present - which they generally are. --------------- Venus has one cooling region, determined by the CO2 as we read from the space, where the heat arrives from both above and below. The equilibrium temperature of this region is simply due to outgoing radiative flux through the CO2 window around 15 microns, which represents only a small part of the total outgoing flux, but enough to set up the temperature profile. The surface of Venus would be considerably colder if CO2 only absorbed in a 1 micron bandwidth at 15 microns. Notice that the radiating region takes place always between two layers both producing an inward heat flux, so while Venus, heated solely at the surface and within the thermosphere, has one middle region which avoids the runaway warming of the planet, Earth, with its three heating region, has to present two emitting regions, whose thermostat is the CO2. In the absence of direct solar heating of the atmosphere and in the presence of greenhouse gases, temperature would tend to decrease with height all the way up to TOA, even above the tropopause, even in layers with no convection! Radiation is not only radiated to space from relative minima in temperature; in fact more radiation is generally emitted from layers with higher temperatures (for the same layer thickness), and the amount reaching space depends on height. Again, heating of an upper layer doesn't cool a lower layer; it can be an indirect heat source via the increased emission from the heated layer, and the cooling effect (absent compositional feedbacks/linkages) only comes from using energy to heat the upper layer that would otherwise have heated the lower layer. Aside from redistributing solar heating, merely adding solar heating, in any layer, will increase the temperature in general, but will tend to have the greatest impact where it occurs, because increased net LW fluxes out of that layer are necessary to balance the increased solar heating. --------- Consider this: What if the Earth, without direct solar heating of the ozone layer, had a troposphere all the way up to where the mesopause now is - let's say 85 km (it might be a bit off of that but I think it's close) Well, first, the lapse rate of what is now the mesosphere would have to increase as presently it is stable to convection. But let's suppose the mesosphere already had a convective lapse rate. In this very high tropopause situation, if we now add solar heating around the level of the stratopause - and let's say, remove it from the surface, what happens? In order to balance the reduced radiant heating of the surface and reduced radiant cooling around the stratopause, the convective flux between those two levels is reduced. But unless you have to reduce it all the way down to zero, the tropospheric lapse rate remains and it still goes from the surface to 85 km; there has been no net forcing on this layer (we only redistributed the solar heating within it), so the surface temperature is unchanged, as is the height of the tropopause and the temperature at the tropopause. Setting aside redistribution of solar energy, adding solar heating to a layer above the tropopause could reduce the tropopause height by raising the temperature at the tropopause level. The indirect heating effect (via LW flux) would tend to warm the surface and troposphere. The cooling effect if this solar heating was not added to the system as a whole but taken from beneath the troposphere will tend to be stronger than the indirect heating effect from the LW flux. But see above for a quantitative example. Mesosphere. Really, I do not care one bit if the mesosphere is convective or not. It is enough for my aim that there exists a upward heat flux within the mesosphere. Which is mainly radiative. Not convective. I will add that I recently realized (from this paper http://journals.ametsoc.org/doi/pdf/10.1175/JCLI3829.1 "The HAMMONIA Chemistry Climate Model: Sensitivity of the Mesopause Region to the 11-Year Solar Cycle and CO2 Doubling" Schmidt et al. ) that some or much solar heating of the upper atmosphere, going into chemical reactions, is not all realized as sensible heat right away; some portion can exist as latent heat (chemically) which can be transported before conversion to sensible heat. But motions are mainly thermally indirect, driven by fluid-mechanical wave energy from below the tropopause. I PS see fig 10 of that paper - note the solar heating of the atmosphere above the 1 mb level (1 mb = 100 Pa) is less than 1 W/m2. (With surface gravity at 9.81 m/s2, a flux of 0.118 W/m2 per mb is required per K/day heating rate. At 100 km height, with the slight reduction in g, this is 0.122 W/m2 per mb per K/day. So from the surface up to 100 km, we could just get by using 0.12 W/m2 per mb per K/day)
81053. Camburn at 07:31 AM on 28 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Albatross: If you had read the NOAA link, you would have seen the IRI graph. I stated plainly that NOAA is predicting a La Nina quit soon. NOAA is the US, where I live, predominant weather/climate forcaster. As far as my interest in La Nina? Where I live a La Nina keeps us cold and wet. An El Nino has a very limited effect, whereas a La Nina has a huge effect. Nothing to do with being skeptical, everything to do on where one lives.
81054. Albatross at 06:55 AM on 28 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Camburn @8, What is the fascination that "skeptics" have for La Ninas? Is it becasue they can cause a transient drop in global temperatures of up to 0.2 C? "Skeptics" have to keep focusing on the potential for cooling (real or imaginary) and ignore the long term trends it seems... And from your NOAA link: "ENSO-neutral conditions are expected to continue at least through the Northern Hemisphere summer 2011." Your definition of "soon" must differ quite a bit from that of NOAA's. Please do not misrepresent NOAA. For an idea of what all the dynamical and statistical guidance is suggesting, go here. [Source]
81055. Camburn at 06:47 AM on 28 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Dr. Masters: Do you think the intensity and number of hurricanes/tropical cyclones etc will continue as low in intensity and numbers as research by Dr. Maue shows? Dr. Maue's findings
81056. Camburn at 06:41 AM on 28 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Ref to La Nina El Nino. NOAA seems to be forcasting a return to La Nina contions quit soon. NOAA Prediction
81057. hfranzen at 06:14 AM on 28 June 2011
       Uncertainty in Global Warming Science
       emelio.gagliardi: Since I wrote the essay I guess I should provide an aswer to at least the first half of your question. Some examples of Type A science that occur to me "off the cuff" are: rocket trajectory, clectial mechanics, partical trjectories, electron orbits in atoms and molecules, sunchroton trajectories, atomic and molecular spectra. Some examples of Type B science are: weather prediction, river bank errosion, corrosion, automobile traffic flow, disease transmission. For Type C science I would suggest: population growth, the Keeling curve, the trajectory of an arrow, the earth's temperature vs. time. melting of an ice sheet. I want to congratulate you on your conern about communicating GW science to the general public - this is an extremely important activity! However I am afraid that contributing ideas about how to discuss this topic in a fashion better suited to technically uninformed audience is beyond my ability,
81058. actually thoughtful at 06:13 AM on 28 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Dr. Masters - great post - I found it on WeatherUnderground and thought it would be a great fit here - it is! Speaking from a position of ignorance - is global warming going to lead to much faster El Nino/La Nina cycles? I see that Jeff thinks we are due for a few quiet years, but I'm thinking more along the lines of Rob Painting. It seems a system seeking balance would experience more ENSO shifts, and very recent trends support that.
81059. hfranzen at 05:36 AM on 28 June 2011
       Uncertainty in Global Warming Science
       Kevin C.: Thanks for your commment and questions. The catagories of science that I propose are totally my own and are presented with the purpose of trying to rationalize arguments about the science of GW. To my way of thinking there is a heirarchy of arguments about GW science, namely: 1. about science with uncertainties that can be numerically determined and shown to be negligible(Type A), 2. about those concerning science with larger uncertainties that are basically estimates based upon past experience (Type B) and 3. those about science which describes phenomena in terms of a curve fitted to data using empirical curve fitting (Type C). I express the opinion that to disagree with the results of Type C science and infer or conclude that this disagreement is tatmount to disagreeing with the totality of GW science is not productive. That is, someone who wishes to deny GW science should be very explict about the level of their disagreement in the heirarchy. For example, if one wishes to express a criticism of the earth's temperature vs. time curve during some particular epoch it would be very helpful to all involved if they would make clear at the outset at what point in the heirarchy they part ways with the accepted scientific picture. The nature of the discussion will, I think, be very different if they say at the outset that they simply do not believe CO2 has anything to do with GW as opposed to saying that they understand and agree with the basic understanding of the interaction of the earth's Planck radiation with atmospheric CO2 but want to raise a specific point about the interpretation of the specific data for that epoch.
81060. Tor B at 05:15 AM on 28 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Puyehue is having a tiny eruption compared with Tambora (1815), with a Volcanic Explosivity Index (VEI) of 4 compared to Tambora's 6.5 - 7. (mostly from BigThink) "From: NASA's Earth Observing Project Science Webpage: Volcanoes and Global Climate Change, May 2000 Volcanic eruptions are thought to be responsible for the global cooling that has been observed for a few years after a major eruption. The amount and global extent of the cooling depend on the force of the eruption and, possibly, its latitude." USGS publication Latitude may matter because there is more solar gain in the tropics than at the poles. At the extreme, SO2 (etc.) blocking some equatorial sunshine will affect a season's weather more than blocking all polar winter "sunshine". Of course, the ash and gasses don't remain at the latitude at which they were erupted and can affect weather for multiple seasons. Equatorial eruptions tend to affect weather in both hemispheres while higher-latitude eruptions affect mostly only their own hemisphere.
81061. John Hartz at 03:39 AM on 28 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Kudos to Dr. Masters on very well written and most timely article. The graphics stunningly amplify the text.
81062. anarchic_teapot at 03:20 AM on 28 June 2011
       New Zealand Snow No Show = No Jobs
       There's a similar trend in the Alps and Pyrenees in Europe, to the extent that ski resort operators had considered asking for bailouts. A lot try to alter alternative activities, like hillwalking, but it's not a replacement.
81063. Chris G at 02:37 AM on 28 June 2011
       A journey into the weird and wacky world of climate change denial
       Pedantic correction: The effect is on a curve with a declining slope, but the slope is always positive and the curve has no upper limit.
81064. Camburn at 02:35 AM on 28 June 2011
       Uncertainty in Global Warming Science
       dhogaza: Yep, you are understanding it. TSI can not explain the early 20th century warming. Nor can it explain the decline in warmth....nor the increase again in warmth. I don't know if Svalgaard will trump all other papers. His will be another addition. There are so many different reconstructions of TSI that have been published who knows? He is eminent in his field, has come up with a solution to the wide variance in the published works that seems very plausable. The bulk of the latest evidence is leaning in his direction tho.
81065. Chris G at 02:29 AM on 28 June 2011
       A journey into the weird and wacky world of climate change denial
       The emotional bias in the arguments can be seen whenever there are three conflicting lines of reasoning, but only one is engaged by the other two. For example: a) CO2 is a trace gas and can have no effect; there isn't enough of it to have any effect. b) The thermodynamic effect of CO2 is logarithmic; it's effect is on a declining slope, but that slope has no upper limit. c) CO2 is already at such high concentrations that more of it can have no effect. Proponents of (a) and (c) will argue with proponents of (b), but never with each other. If the debate were about physical reality, a and c would go after each other, possibly even attempting to recruit b as an ally. But, they don't engage each other, ever. Instead they always go after b together. Why? Because the implications of b are emotionally difficult to deal with, and the implications of a and c are not emotionally threatening to each other. This pattern belies any attempt to present the argument as one based on the technical merits of the positions.
81066. Michele at 02:06 AM on 28 June 2011
       The Planetary Greenhouse Engine Revisited
       I would remember that we are not arguing about the global fluxes assuring the planetary energetic balance, but about the GH effect that found on any modification of the temperature profiles with regard to the isothermal one that would be there if the atmosphere was perfectly transparent. Venus has one cooling region, determined by the CO2 as we read from the space, where the heat arrives from both above and below. The equilibrium temperature of this region is simply due to outgoing radiative flux through the CO2 window around 15 microns, which represents only a small part of the total outgoing flux, but enough to set up the temperature profile. Notice that the radiating region takes place always between two layers both producing an inward heat flux, so while Venus, heated solely at the surface and within the thermosphere, has one middle region which avoids the runaway warming of the planet, Earth, with its three heating region, has to present two emitting regions, whose thermostat is the CO2. A single molecule with the necessary properties can emit a single photon (or absorb one). Yes in an EM radiating field. Not at all for the processes based on the collisions among the molecules as heat->EM and vice versa. Mesosphere. Really, I do not care one bit if the mesosphere is convective or not. It is enough for my aim that there exists a upward heat flux within the mesosphere.
81067. Martin at 02:05 AM on 28 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       You mention Indonesia's volcano Tambora (1815) and the year without a summer. What effect will, in your opinion, Chile's Puyehue volcano (2011)have?
81068. Chris G at 02:02 AM on 28 June 2011
       A journey into the weird and wacky world of climate change denial
       Chemware, While I don't really meet your minimum requirements, one of my degrees is a masters in cognitive psychology, but I don't work in that field now. Mostly I worked on how the brain processes visual information, but I did manage to pick up some awareness of social and clinical aspects through osmosis. From what I've seen, there are aspects of projection that come into play, but mostly it appears that various aspects of denial, very aptly named, come into play. Also, a fair amount of cognitive dissonance can be observed amongst the crowd. However, I think it is important not to paint with too broad a brush; individuals can vary from those that are motivated by profit to those who are honestly not able to connect the dots between cause and effect. Of the latter, the failure can be caused by lack of skill in the physical sciences, or a psychological blockage that prevents acceptance of what is really known, or others that don't come to mind as readily. Denial is a powerful survival skill, but it does sometimes prevent dealing with the reality of the situation. IMHO, cognitive dissonance manifests itself often as the slight derailment of an otherwise coherent line of thought, when that derailment changes the line to so that it leads to conclusions that are more comfortable. Also, if plain and simple presentation of information provokes a strong emotional response, the odds are good that you are getting near that person's keystone of denial. Of course, different people have different keystones. The list of expressions of denial on the link above almost looks as though it were tailor made for the climate denier crowd. I like the Max Planck quote; still true to this day. I don't think the argument/debate will ever be completely over. As new people are made aware of the problem, the general tendency toward denial will keep some directed to that side of the debate. It is not easy to accept that you are culpable in creating a world where your children will have a more difficult life than the one you have enjoyed. I see this as an ongoing educational effort.
81069. Tor B at 01:28 AM on 28 June 2011
       New Zealand Snow No Show = No Jobs
       The last time I ice skated was at Lower Manorburn Dam (NZ) during a student outing in 1977. The ice was thin in places and, falling spectacularly once, I cracked the ice. Sad to think that such pleasures (?) are already (apparantly) harder to come by.
81070. Dikran Marsupial at 01:21 AM on 28 June 2011
       Uncertainty in Global Warming Science
       Ken Lambert wrote: "If TSI is above an 'equilibrium' value and stays constant -there is a constant imbalance in forcing which translates to a linearly increasing gain in energy" This is simply incorrect, if there is an energy imbalance, global temperatures rise until the resulting increase in outbound IR is sufficient to restore the balance an a new equilibrium is established. Temperatures would not increase linearly, and neither would the gain in energy. We know the equilibrium value for atmospheric CO2 (about 280 ppm), if CO2 levels are maintained at a constant level above this equilibrium value, then again there will be an energy imbalance, but will temperatures increase indefinitely? No. So why is TSI forcing different from CO2 radiative forcing? N.B. I have pointed this out before without a getting a reply.
81071. KR at 01:14 AM on 28 June 2011
       Uncertainty in Global Warming Science
       Ken Lambert - "If TSI is above an 'equilibrium' value and stays constant -there is a constant imbalance in forcing which translates to a linearly increasing gain in energy..." As has been pointed out more than once, Ken, a constant imbalance could only be maintained if the TSI was increasing (not 'constant') to stay ahead of the increasing TOA radiation to space due to increasing temperatures. That's not happening. We have excellent data on TSI, very precise in noting changes in insolation even if there are inter-satellite absolute calibration uncertainties - we simply do not have the constantly increasing insolation required to drive the temperature changes of the last 30-40 years. Your hypothesis is quite simply contradicted by the facts. I suggest taking additional comments in your ongoing TSI discussion back to it's the sun, where this has been repeatedly disproven. As a serious point, Ken, you seem to be unable to absorb any information on this topic. You've repeated the same incorrect assertions over and over and ... (repeat as necessary), and have had the errors in your hypotheses pointed out each time. Why do you continue to insist on this contrary to actual measurements?
81072. Bob Lacatena at 01:14 AM on 28 June 2011
       Uncertainty in Global Warming Science
       Camburn, Ken, In any event, all of this discussion of solar is OT. I know you'd like to claim that it has to do with uncertainty in climate science, but really, that pretty much sums up just about any denial argument there is. It would turn this thread into a denial free-for-all. We should close with Dr. Franzen's well framed characterization of the science, and perhaps turn to answering emilio's (relevant) question.
81073. Bob Lacatena at 01:11 AM on 28 June 2011
       Uncertainty in Global Warming Science
       55, Ken,

       TSI does not have to vary over the short to medium term...

       Yes and no, but not all that relevant. I'd argue that yes, solar variation can only have so much impact on climate, and must involve a variation over a long time scale, but the 11 year cycle obviously does come into play on short time scales... but not really in climate.

       ...then we cannot accurately determine the gain or loss of energy from TSI.

       This is false. We just got done discussing the papers that attempt to estimate the energy imbalance. Declaring out of hand that we simply can't do so is just wrong.

       If TSI is...

       This is all rather simplistic conjecture and thought-modeling that does nothing to advance the conversation. Certainly, I don't believe you have anything that can support this simple model as a premise, or any conclusions that you might draw from it.
81074. mspelto at 00:26 AM on 28 June 2011
       New Zealand Snow No Show = No Jobs
       You can always utilize more advanced snowmaking like at Pitzal Glacier, or a glacier blanket like at Presena Glacier , assuming you have a bit of glacier underneath.
81075. skywatcher at 00:12 AM on 28 June 2011
       New Zealand Snow No Show = No Jobs
       There's been similar issues for the Scottish ski areas until the last few years - they were really struggling for snow some years. That's changed in the past couple of years to bumper conditions, but of course the cause for that is as likely as not global warming-related too, see Jeff Masters' excellent recent post. It will be interesting to see if NZ can be subject to such climate surprises, but I suspect the stability offered by an ice-covered ocean-surrounded continent will not offer the same potential for Arctic/Antarctic air moving out into temperate regions for the southern hemisphere compared to the north. This has created the illusion of a cold world for some in NH regions who fail to see the bigger picture, but maybe that illusion is not possible in the south?
81076. Ken Lambert at 00:05 AM on 28 June 2011
       Uncertainty in Global Warming Science
       Camburn, Sphraerica TSI does not have to vary over the short to medium term - years to decades to cause a warming imbalance (Earth to gain energy). Since we don't really know the 'equilibrium TSI' at which Earth is not warming nor cooling in the absence of AG forcings, then we cannot accurately determine the gain or loss of energy from TSI. If TSI is above an 'equilibrium' value and stays constant -there is a constant imbalance in forcing which translates to a linearly increasing gain in energy - and a roughly linear gain in temperature of a fixed mass of ocean, dirt and air and phase change at constant temperature for ice and water.
81077. JMurphy at 00:01 AM on 28 June 2011
       Sea Level Hockey Stick
       okatiniko wrote : "sean : I'm ready to discuss with everyone. Tamino isn't. That's life." I'm sorry but this can't be allowed to stand without the facts being known. Just in case someone reading this does not go to Open Mind to see why Tamino doesn't put up with such commenters, here are some of the relevant comments from him about okatiniko : Ignorance is reversible. But I don't believe you're really ignorant of these facts. I believe you want to *appear* to ask "questions" but it's just a thinly veiled facade. And when any of your errors are revealed (like your faulty, made-up definition of climate sensitivity of malignant design), you dare not admit any mistake, you just move on to the next talking point. When I first suggested that you might be more interested in arguing than in learning -- I had you pegged. Doubt is your product, it has been your only goal all along. I think everyone should know exactly what type of denial exists out there, and how it is repeated on different sites, often by the same people, and often falsely claiming to ask innocent questions. The question is, though : Why should we put up with it ? Especially from those claiming that they want to disuss things - in the same vein as Creationists do with regard to Evolution.
81078. CBDunkerson at 00:00 AM on 28 June 2011
       The false, the confused and the mendacious: how the media gets it wrong on climate change
       Robert, I largely agree with your free speech concerns but there are two issues which stand out in this case. 1: In the past the idea of deliberate and ongoing deception by major elements of the news media was unthinkable. Anyone engaging in such chicanery would be run out of the profession. Now, it is practically a job requirement for a position at Fox News and the like. This represents a grave threat (i.e. widespread false beliefs are poison to democracies) which somehow must be addressed. 2: Lying under oath has always been an obvious exception to the 'freedom to lie'. If people can lie with seeming impunity in government hearings and courtroom proceedings it removes any chance of exposing those lies or stopping their effects. I agree that a 'truth commission' isn't a viable solution, but we need some kind of solution. We can't continue to allow 'truth' to be defined by the most practiced liars.
81079. Rob Painting at 23:37 PM on 27 June 2011
       CO2 has a short residence time
       Dikran/Eric - this seems relevant to your discussion: Ongoing climate change following a complete cessation of carbon dioxide emissions - Gillett 2011
81080. KR at 23:35 PM on 27 June 2011
       CO2 has a short residence time
       Eric (skeptic) - "KR, I must have insinuated something I didn't mean to ("50 year time cycle for full equalization")." You're quite correct, Eric, my apologies. I misread your post, which clearly refers to 50 years as the half-life. Sorry about that. That's fairly reasonable - my back of the envelope check on this indicated a half-life of ~40 years assuming absorption rate was proportional to excess over pre-industrial levels. Although, given the 340-350GT we've added to the carbon cycle from sequestered fossil fuels, and the multiple absorption paths with different equalization times, I don't think it's as simple as a single half-life. The rise in temperature from the added GHG's will mean an equilibrium level of ocean absorbed CO2 lower than in pre-industrial times, for example. Oops! Reading the past few posts, it appears Dikran has beaten me to these points with much better information...
81081. Eric (skeptic) at 23:28 PM on 27 June 2011
       CO2 has a short residence time
       That would make sense since it is a hypothetically plausible scenario unlike my academic cut-to-zero scenario.
81082. dhogaza at 23:22 PM on 27 June 2011
       Uncertainty in Global Warming Science
       Camburn: "It would seem Bertrand's research on solar agrees with Dr. Svalgaard. "Bertrand was investigating the effect of solar and volcanic influence on climate and concluded "these are clearly not sufficient to explain the observed 20th century warming and more specifically the warming trend which started at the beginning of the 1970s"." I don't think Camburn understands that the implication of Bertrand's research (assuming he cites it correctly) is that TSI hasn't caused the warming trend that started at the beginning of the 1970s. In other words "it's not the sun, rather than CO2". Strengthens, not weakens, the case of sensitivity to a doubling of CO2 being higher than denialists like Camburn so fervently want to believe. Now if Svaalgard's paper holds up over time, then yes, there's something not well understood about early 1900s warming. However, it's not claimed by climate scientists that the cause of this warming is perfectly understood. Camburn will be sure, though, that Svaalgard's *reconstruction* regarding TSI trumps all observations regarding CO2's role as a GHG, positive water vapor feedback, TOA satellite measurements, etc etc etc.
81083. Dikran Marsupial at 23:21 PM on 27 June 2011
       CO2 has a short residence time
       Eric@107 AFAIK, levels will fall (excluding variability) as soon as we cut our emissions to zero, however it could be that DB knows something about it that I don't (very plausible!). It could be that DB meant cutting emissions to some stabilisation level, rather than to zero?
       Moderator Response: (DB) Dikran, I was referring to something which came up on Dr Franzen's first post several months ago that, as CO2 level stabilize and then fall, that the oceans will begin to outgas CO2 themselves, going from sink to source & preserving elevated CO2 levels (& temps) at elevated levels compared to preindustrial; look in the comments in that post for the direct discussion (I'd link to it but we're camping out in the bush& I barely have a cellphone signal).

       [Dikran Marsupial] Cheers DB, I thought it would be something like that. It's swealteringly hot in my office, I wish I were outdoors! ;o)
81084. Rob Painting at 23:14 PM on 27 June 2011
       New Zealand Snow No Show = No Jobs
       After a record warm May 2011 (2.5°C above average) and (possibly) June looks like we've dodged a bullet, a cold snap and light dustings of snow have finally arrived!
81085. Robert Murphy at 23:05 PM on 27 June 2011
       The false, the confused and the mendacious: how the media gets it wrong on climate change
       #11: "Consider Fred Singer... He has been at it for decades and doesn't appear to have ever suffered any sort of 'consequences'" Sure it has - he's a pariah among scientists. He has no academic career to speak of and hasn't for years. What more do you want to do? Send him to jail for saying nonsense? Make it illegal for him to speak in public? Where does it end? Jail the scientologists? The creationists? The flat-earthers? I'm sorry, but free speech entitles one to make a fool of oneself and spout outright nonsense. Yes, that means you can lie, as long as you don't break libel/slander laws. Bill, #12: "News consumers are entitled to believe that they will be given the core scientific information without distortion." No, they are not. They are obligated to check what they read. Caveat emptor. That goes for any kind of information, not just scientific. "Any media outlet that strays so far from the public-interest should risk serious penalty, including revocation of licence." And when your enemies gain control of the bureaucracy, YOUR point of view will suddenly stray from the "public interest". Claim the hockey stick is not broken or that the warming has not stopped? They'll say that's a lie and cut you down with the legal weapons you gave them. '"Free speech" does not run to the right of near-monopolies to propagandise at will' Murdoch's media empire, however widespread, is no monopoly. I can easily get all the information I desire from other sources, with no inconvenience. I personally don't choose to eliminate any news outlet totally, but I could if I wanted to. And frankly, all media outlets, bloggers, pamphleteers, and street corner orators have a right to propagandize at will. In the U.S. we call it the 1st amendment. People, think about what such a Truth Commission would mean in practice. It would do far, far more damage than anything the deniers do now. I shudder at the thought of some nameless bureaucrat deciding whether or not someone's scientific or political opinions are illegal. In that sense I'm a 1st amendment fundamentalist.
81086. Eric (skeptic) at 23:02 PM on 27 June 2011
       CO2 has a short residence time
       Dikran, it seemed to be suggested in a moderator note here: /news.php?p=2&t=116&&n=790#55671 Did I misinterpret that?
81087. Rob Painting at 22:27 PM on 27 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Yeah, I'm picking El Nino by years end, based on an Indian Ocean Dipole paper. The NOAA SST page seems to suggest an El Nino might on the way too.
81088. bill4344 at 22:17 PM on 27 June 2011
       The false, the confused and the mendacious: how the media gets it wrong on climate change
       I agree with Tom Curtis. The Murdochracy has really gone out of its way to routinely provide outright disinformation in this matter, and I'm glad it was singled out in The Conversation series. News consumers are entitled to believe that they will be given the core scientific information without distortion. Particularly on such a vital issue. And certainly without the sordid pretense that serving up think-tank spin is some kind of equivalent! Instead, the product is blatantly faulty - so where is the redress? Any media outlet that strays so far from the public-interest should risk serious penalty, including revocation of licence. "Free speech" does not run to the right of near-monopolies to propagandise at will, any more than it entitles corporations to lie in their advertisements - that is an absurd perversion.
81089. dorlomin at 22:15 PM on 27 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       http://discover.itsc.uah.edu/amsutemps/ Link here, seems to be a huge amount of warm water in the Pacific atm.
81090. CBDunkerson at 22:11 PM on 27 June 2011
       The false, the confused and the mendacious: how the media gets it wrong on climate change
       Consider Fred Singer... the man has been a professional denier for about 40 years now. He has argued that ultraviolet light does not cause skin cancer, CFCs do not cause ozone loss, smoking does not cause lung cancer, asbestos and DDT are perfectly safe, et cetera. He has been at it for decades and doesn't appear to have ever suffered any sort of 'consequences'. Sure, he has been denounced as a fraud many many times... but it doesn't seem to have hurt him any. He is still considered a 'heroic truth-teller standing up to the commie scientists and tree-huggers' by far too many people. I used to think that the only thing which could ever stop such people is if they were foolish enough to lie under oath... but then Monckton got away with even that.
81091. dorlomin at 22:10 PM on 27 June 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Brilliant Post Dr Masters, read it over at wunderground. Oh and all SkS readers, check out the current UAH discover websites temperatures we've been near record highs all June.
81092. Dikran Marsupial at 21:47 PM on 27 June 2011
       CO2 has a short residence time
       Eric@105 I don't recall ever having seen a claim that CO2 will continue to rise if anthropogenic emissions stop completely (other than a short term increase due to natural variability). Can you give a specific example? The decay is not a simple exponential, one model the IPCC uses is the sum of four exponentials with differint weights and decay rates. Clearly by that model, CO2 would not increase if anthropogenic emissons stopped tomorrow. The argument about the new equilibrium seems risky to me as the oceans will influence the new equilibrium as well as the terrestrial biosphere. I suspect the calculation is in one of Archer's papers.
81093. Eric (skeptic) at 21:24 PM on 27 June 2011
       CO2 has a short residence time
       KR, I must have insinuated something I didn't mean to ("50 year time cycle for full equalization"). Let me sum up my view which seems to match what Dikran has been posting to me. There is an exponential decay of CO2 back to some equilibrium. It is sometimes posted on other threads that even if mankind stopped producing CO2, CO2 would continue to rise. Although a completely academic argument, the opposite will happen, CO2 will immediately drop about 1/2 way back to preindustrial within 50 years. However the final equilibrium will take much longer, essentially forever as has been mentioned above (but again, that time scale is academic since it is the effects that matter not the amount). Also the new equilibrium will be higher than the preindustrial equilibrium due to our added CO2. That new equilibrium is pretty easy to estimate, we added 340 GtC since preindustrial and the total carbon in the ocean, soil, and biosphere is roughly 3000 Gt, so the new equilibrium is roughly 10% higher than the old as of the end of 2007. Also there will be other rises in that equilibrium due to warming feedback. Those feedbacks are modest right now, but might not be in the future. Finally, I agree with Dikran that there is unrealized warming, but most of that warming is already reflected in sea level since that is where it is stored. But the atmosphere would continue to warm if we (academically speaking) stopped producing CO2.
81094. andrew.glikson at 21:16 PM on 27 June 2011
       The Last Interglacial - An Analogue for the Future?
       Agnostic. Unfortunately I think you are correct ... Andrew 27-6-11
81095. andrew.glikson at 21:11 PM on 27 June 2011
       The Last Interglacial - An Analogue for the Future?
       Steve. You write: "Does this mean that increasing levels of CO2 do not cause global warming after all? Climate always changes and we have nothing to worry about, right?" Unfortunately I can not see that. An alternative explanation is that CO2 levels of ~300 ppm, a mere 20 ppm above pre-industrial Holocene, may be sufficient to raise tempratures by <1 degrees C and sea levels by ~5 meters, implying significantly higher climate sensitivity than Charney's 3+/-1.5 degrees C per doubling of CO2, as indicated by recent papers by Pagani et al. 2010 (PNAS)indicating CS values higher than 6C. Second, the GROWTH RATE of GHG rise may be just as important as the absolute level of CO2. The current rise rate of ~2 ppm/year is higher by a large factor than that preceding the Eemian interglacial, indeed it is the highest recorded in the Cainozoic geological record, and may constitute an important factor, for example in destabilizing methane locked in permafrost. According to Hansen et al. 2011 and Hansen and Sato 2011 total forcing has already reached 3.1 Watt/m2, although about half of this is currently mitigated by transient sulphur aerosols without which we are committed to +2.3 degrees C. These are Pliocene-like levels, well above the Eemian. Andrew Glikson 27-6-2011 Which means, consciously or unconsciously the world is already practicing geoengineering.
81096. Tom Curtis at 21:02 PM on 27 June 2011
       The false, the confused and the mendacious: how the media gets it wrong on climate change
       RobertMurphy @9, I am inclined to agree with you. However, I do think a very interesting case could be run against many News Limited outlets on the basis of false advertising in that they promise to bring us news, but bring us lies instead.
81097. Bob Lacatena at 20:49 PM on 27 June 2011
       Sea Level Hockey Stick
       127, okatiniko, It is unfortunate that you need to have climate change literally slap you in the face before you are willing to recognize it. Still, your obstinate denial in the face of clear evidence will help others to realize that a lot of the people that refuse to recognize climate change are doing so in clear denial of the facts, no matter how cleverly they can package or re-interpret them. More specifically, however, you need to understand the science, and the forcings. The lack of volcanic activity combined with an increase in solar insolation, a rebound from previous volcanic activity, and minor increases in greenhouse gases are all sufficient to account for the warming until 1945. No such forcings exist after 1970. The sun became more quiet, there were notable volcanic eruptions, etc., etc. At the same time, the rate of warming after 1970 is clearly faster than at any other point in the temperature record. That is the blade of the hockey stick, and it doesn't require a strong understanding of statistics to see it. At the same time, Greenland has been losing ice mass at an accelerating rate since 2000. That is the blade of another hockey stick. Arctic ice since the eighties is in an unending downward spiral. That is the blade of another hockey stick. Within a decade or two, increasing droughts will begin to seriously affect agriculture and water supplies in already water starved areas. That will be the rather painful blade of yet another hockey stick. At the same time, sea level rise is certainly going to accelerate, and that will be the blade of yet another hockey stick. That you cannot see any of this, because desperately don't want it to be true, does not change the facts. That you choose to interpret everything as a steady, unending and inexplicable heating of the planet ("Not our fault! Can't be CO₂!") does not change the fact that this is clearly not the case, and that any rational, responsible and open minded person can see this for themselves. Anyone who doubts this can use the links and pages on this site to educate themselves, to understand the physics behind CO₂, and to understand why it would actually be puzzling if all of this weren't happening. And anyone with an ounce of sense and responsibility will look at the Arctic, Greenland, the temperatures, the Amazon, sea levels, the increasing frequency of extreme weather events, and more, and will come to the conclusion that those who are in denial are seriously damaging everyone's future.
81098. Robert Murphy at 20:48 PM on 27 June 2011
       The false, the confused and the mendacious: how the media gets it wrong on climate change
       Liam23@7, Licensing journalists (or bloggers, or whoever else decides to speak) would be a hideous assault on freedom of speech. Who is going to decide those things? Some bureaucratic licensing board? Who is going to decide what was a mistake and what was intentional? What happens when "the other side" gets to run such an agency? What if a Monckton or Plimer type were to head such a board? No, we do not need a Ministry of Truth. For all it's imperfections, the marketplace of ideas needs fewer, not more controls.
81099. les at 19:20 PM on 27 June 2011
       Sea Level Hockey Stick
       127 - okatiniko Just in case people get confused by this statement:

       but between 1900 and 1970, there was nothing really unusual in forcings, nowhere. http://www.ipcc.ch/graphics/ar4-wg1/jpg/fig-9-12.jpg

       due, clearly to the very poor practice of linking to a graph with no axis labels or comments... it comes from here. I think people can draw their own conclusions from the text. As always, beware the eyeball-O-matic; it is not a tool best suited to statistical analysis.
81100. Dikran Marsupial at 17:31 PM on 27 June 2011
       CO2 has a short residence time
       Eric wrote: "Simply put, the top layer ocean carbon has to go somewhere each year so that the top layer can soak up more the next year." This is incorrect, unless the surface waters are saturated, then if atmospheric CO2 rises, then the surface waters will take up more CO2 even if the previous anthropogenic emissions have not been drawn down to the deep ocean. This is because the air-surface ocean flux is proportional to the difference in partial pressure. Even if the surface waters are equilibriated, that does not mean they are saturated. It is correct that, should we stop carbon emissions tomorrow, then levels will fall halfway back to pre-industrial levels within about fifty years. However, that doesn't mean that temperatures won't continue to rise or that sea levels won't rise. The reason is that the excess CO2 that remains still means that the Earth is not in radiative balance, and won't be fully in balance until the oceans have warmed as well as the land. This is why climate sensitivity is equilibrium climate sensitivity, so there is "unrealised" warming yet to come, no matter what we do (of course that doesn't mean we should do nothing).

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