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Comments 130601 to 130650:

130601. chris at 09:29 AM on 25 November 2008
        Models are unreliable
        Re #69 Dan O.K., so you've finally come round to the truism that a downtrend in temperature is not proof that a net positive feedback doesn't exist, after all. So everyone else but you wasn't wrong! Your bad indeed. But we got there in the end... Your second paragraph is illogical. We all know that the Earth's equilibrium temperature response has a logarithmic relationship to the atmospheric CO2 concentration. Arrhenius had worked that out already over 100 years ago. Your third and fourth paragraphs are nonsense too. Why go to a non-science magazine created with the intention (as the Editor admits) of misrepresenting the science on power industry-related matters? We've already seen (see posts #54 and #58) that "articles" in that magazine on climate-related matters are dodgy. Not surprisingly, the author of that article has got it wrong. There are lots of errors: (i) absorption of EM radiation doesn't "take place close to the surface". Photons can travel vast distances before being "absorbed". It depends on the absorbtivity/transmisivity of the medium through which the photons pass. (ii) If one considers longwave IR emitted from the Earth's surface, the wavelength/energy of the emitted wavelength has to be considered, since the absorption coefficient (k) is inversely related to the wavelength of the absorption band. The transmisivity, t, (absorbtivity = 1-transmisivity) of a column of air = t = e^(-k*p*l) where k is the absorption coefficient, p is the partial pressure and l is the path length. since the absorption coefficients for the absorption bands of the greenhouse gases are known[1], we can calculate the pathlength required to effectively absorb all of the radiation (at that energy/wavelength). For 99% absorption, the pathlength of the 4-5 micron absorption band of CO2 is 625 metres at current atmospheric CO2 concentrations and for the ~14-20 micron absorption band, CO2 at 385 ppm is still unsaturated at 7,800 metres of altitude. likewise for the 12-20 micron infrared absorption band of water at 0.4%, water vapour is still absorbing at 1,700 metres. (iii) in other words at current atmospheric greenhouse gas concentrations, the absorption bands aren't saturated, and enhancement of the concentration of greenhouse gases, particularly at higher altitudes [see (iv)], is effective in trapping more of the longwave IR emitted from the Earth's surface. (iv) In any case, the altitude of absorption of IR emitted from the Earth’s surface isn’t that important. A key element of the greenhouse effect is the altitude of emission of longwave IR into space. This has to happen for radiative balance between incoming radiation and outward radiation. You’ve actually given a clue to an important consideration unwittingly in the very first statement of your post: [Dan “bad boy” Pangbourn: “Radiated energy (from all surfaces, including earths) varies as the fourth power of absolute temperature”] Exactly so. As greenhouse gases are added to the Earth’s atmosphere, the radiation of IR into space is suppressed at any altitude (especially altitudes far from the Earth’s surface). So the radiation emitted to space from (say) 5 km is suppressed by enhanced CO2 concentrations, and so the altitude of mean radiation to space is increased. Since an increased altitude in the troposphere is at a lower temperature, the efficiency of radiation to space is decreased (as you said yourself). What’s the effect of this? The troposphere must warm in order to restore radiative balance. Since the surface and troposphere are strongly coupled, the warming of the troposphere is transmitted to the earth’s surface (and vice versa) [2]. (v) The article in the anti-science journal that you linked to makes three more errors that relate to ignoring real world measurements. These are: (i) on page 1044 your ill-informed author states: “It would be expected that more CO2 would have a greater effect on atmospheric warming at higher altitudes, but that seems not to be occurring in spite of the predictions of most GCMs”. But as we’ve seen already on this thread, the tropsopheric warming is quite consistent with GCMs (see my posts #60 and #66, where this exact issue is addressed). (ii) on page 1045 your ill-informed author states: “The GCMs take feedbacks into account, such as the supposed positive feedback from extra warming caused by the radiation by extra water vapour”. Yes, exactly. In line with the enhanced tropsopheric warming caused by enhanced [CO2], the troposphere is accumulating extra water vapour rather in line with predictions [3-7]. According to your ill-informed author this shouldn’t be happening since adding extra greenhouse gases isn’t (according to him) supposed to make the troposphere warmer! (iii) and overall your ill-informed author neglects to state that we can measure in the real world, not only the longwave radiation transmitted down to the Earth’s surface from the troposphere (which shouldn't be happening according to your ill-informed author), but the enhancement of this radiation due to the enhanced greenhouse gas concentrations of the last 30 years (which also shouldn't be happening according to yuor ill-informed author), or the reduction in this radiation outwards to space [8-12] ---------------------------------------- [1] this has been known for decades. See e.g RM Goody and GD Robinson (1951) Quart. J. Roy. Meteor. Soc. 77, 153 [2] Shine, KP (1995) Spectrochimica Acta A 51, 1393-4. [3] Santer BD et al. (2007) Identification of human-induced changes in atmospheric moisture content. Proc. Natl. Acad. Sci. USA 104, 15248-15253 [4] Soden BJ, et al (2005) The radiative signature of upper tropospheric moistening. Science 310, 841-844. [5] Buehler SA (2008) An upper tropospheric humidity data set from operational satellite microwave data. J. Geophys. Res. 113, art #D14110 [6] Brogniez H and Pierrehumbert RT (2007) Intercomparison of tropical tropospheric humidity in GCMs with AMSU-B water vapor data. Geophys. Res. Lett. 34, art #L17912 [7] Gettelman A and Fu, Q. (2008) Observed and simulated upper-tropospheric water vapor feedback. J. Climate 21, 3282-3289 [8] Harries JE et al (2001) Increases in greenhouse forcing inferred from the outgoing longwave radiation spectra of the Earth in 1970 and 1997. Nature 410, 335-337. [9] Worden HM et al. (2008) Satellite measurements of the clear-sky greenhouse effect from tropospheric ozone. Nature Geoscience 1, 305-8. [10] Philipona R et al (2004) Radiative forcing - measured at Earth's surface corroborate the increasing greenhouse effect. Geophys. Res. Lett. 31, art # L03202. [11] Wild M et al. (2008) Decadal changes in surface radiative fluxes and their role in global climate change Adv. Global Change Res. 33 , 155-167. [12] Philipona R et al (2005) Anthropogenic greenhouse forcing and strong water vapor feedback increase temperature in Europe Geophys. Res. Lett. 32, art # L19809. etc. etc. etc. etc……
130602. Mizimi at 09:11 AM on 25 November 2008
        Water vapor is the most powerful greenhouse gas
        Try: http://yosemite.epa.gov/oar/globalwarming.nsf/UniqueKeyLookup/SHSU5BUM9T/$File/ghg_gwp.pdf which gives warming potentials; (and they acknowledge WV is a GG and address their tables to 'selected' GG's) and: http://cdiac.esd.ornl.gov/pns/current_ghg.html (which doesn't acknowledge WV...and their data is NOT just AGG's........unless you deem we are responsible for all the pre-1750 gases ???) If you check the math from table 2 in the EPA site ( which can be checked against the DOE site) CO2 accounts for ~72% of GG warming EXCLUDING WV. CH4 about 7% and N2O 19%, the rest is CFC's etc. Now factor in WV at 95% (topend) and CO2 is responsible for 72% of 5%...3.6% of the total, or 1.19C Take the lowend 90% WV and you get 7.2% of the total or 2.38C Now run the increases due to man's contributions alone and you will get the numbers I quoted in #29
130603. Quietman at 09:10 AM on 25 November 2008
        Misinterpreting a retraction of rising sea level predictions
        chris forget it, the damn graph was drawn backwards.
130604. Quietman at 09:05 AM on 25 November 2008
        Misinterpreting a retraction of rising sea level predictions
        The wording I used is misleading and I did not realize how it would be taken. The high points decline slightly but the lower end is constantly getting warmer, ie. instead of saying it's getting warmer I should have said its not getting as cold. Just follow the trend line of the coldest points to see what I meant.
130605. chris at 05:47 AM on 25 November 2008
        Water vapor is the most powerful greenhouse gas
        I have checked them out. Your numbers are nonsense and don't come from the DOE or from the IPCC. The data on Greenhouse Gas concentrations from the US government CDIAC refer to anthropogenic greenhouse gas and so don't include water vapour. Is that what you're on about? e.g. http://cdiac.esd.ornl.gov/pns/current_ghg.html But we don't really know what you're talking about unless you give us a link to the data that you cut 'n pasted those weird numbers from.
130606. Quietman at 04:20 AM on 25 November 2008
        Volcanoes emit more CO2 than humans
        More on Tectonic activity and poor instruments: "On May 12, 2008, at 2:28 p.m., China's Szechwan province changed forever. In the space of 90 seconds, an earthquake equivalent to 1,200 H-bombs pulverized the earth's crust for more than 280 kilometers. Entire cities disappeared and eight million homes were swallowed up. This resulted in 70,000 deaths and 20,000 missing." "According to ShaoCheng this tragedy could have been avoided. "There hasn't been one earthquake in Szechwan province for 300 years. Chinese authorities thought the fault was dead," he says. The problem is that China relied on GPS data, which showed movements of 2 mm per year in certain areas when in reality the shifts were much bigger. "GPS is high-tech, but do we really know how to interpret its data?," he questions." Ref: Can China's Future Earthquakes Be Predicted? ScienceDaily (Nov. 24, 2008)
130607. Mizimi at 05:57 AM on 24 November 2008
        Water vapor is the most powerful greenhouse gas
        The numbers are not cut and pasted but taken from the sites mentioned. Check them out yourself. The DOE site does not include WV in their GG listing so I take that as ignoring its effect as a GG. The 95% WV quoted is the 'high' side figure from various sites; the 'low' side figure generally quoted is 90% from other sources and one can rerun the sums using the 90% if desired. The rest is simple maths. I included WV in the calcs for obvious reasons.
130608. Patrick 027 at 15:48 PM on 23 November 2008
        Arctic sea ice melt - natural or man-made?
        Now I'm getting ahead of myself, but I wonder if maybe the longer-term trend in AO/NAM might be somehow related to changes in meridional momentum transport - if the residual mean meridional circulation (forced by EP fluxes) isn't changing, this doens't necessarily mean the gradient in zonal momentum that it crosses is not changing. Also - it seems odd to use this to describe a climate CHANGE - it is more obviously applicable to short term weather - but, as there is enhanced warming of the Arctic ocean and high latitudes particularly in winter relative to lower latitudes, this would tend to produce a 'thermal low' in the absence of everything else - and that would tend to pull air poleward at the surface (relative to whereever it goes otherwise) and push air equatorward at mid and high levels (relative to whereever it goes otherwise) and the coriolis effect would increase westerly winds at the surface - but while reducing them aloft; okay, that didn't work, but there could be more to it than that - maybe - I don't know...
130609. Patrick 027 at 15:41 PM on 23 November 2008
        Arctic sea ice melt - natural or man-made?
        After wrapping up Rossby wave basics, I'll get back to AO/NAM (I've found one source which suggested that changes in planetary wave propagation caused by AGW could account for some of the multi-decadal trend in AO/NAM (NAM(1); however I found one paper which argues that while shorter variations of AO/NAM are linked to planetary wave flux changes, the longer-term trend doesn't seem to be so linked. (NAM(2)) Interestingly I think they focussed on a time of year when ozone depletion wouldn't be a direct factor (radiative heating/cooling), but also I'm not sure if solar changes could also be ruled out at least as far as being a direct influence via radiative heating/cooling of the polar stratosphere at the time the AO changes occur. I'm not clear on whether AGW would directly radiatively cool the lower winter polar stratosphere more than the lower winter mid-latitude stratosphere, although that seems to be the trend... Then again there's also gravity waves - did the paper include gravity waves? - no, I don't think it did... anyway, that's coming up...
130610. Patrick 027 at 15:16 PM on 23 November 2008
        Arctic sea ice melt - natural or man-made?
        I've decided not to go into 'absolute momentum' unless specifically asked. The other point I was going to make was that vorticity is proportional to an angular momentum per unit mass per unit area (for circular motion at radius r, counterclockwise tangential speed v (at all points on the circle, or averaged), the angular momentum per unit mass is v*r, the circulation is v*(2*pi*r), and the area-average enclosed vorticity is the circulation divided by enclosed area, v*(2*pi*r)/(pi*r^2) = 2*v/r. Notice that v/r is the angular frequency, and the vorticity is twice the angular frequency. f is equal to twice the planetary angular frequency times the sine of the latitude, and including f, the absolute angular momentum per unit mass is v*r + 1/2*f*r^2; multiplying by 2*pi and dividing by area to get absolute vorticity, the result is 2*v/r + f, where 2*v/r is the relative vorticity. Angular momentum can also be defined for any parcel of air relative to some other parcel or point - it is then less precisely related to the vorticity in the space between. On a small scale, an intrinsic absolute angular momentum may be conserved whenever potential vorticity is conserved (when absolute vorticity is inversely proportional to an area defined by material lines), but angular momentum defined relative to any point is not necessarily conserved following the air under the same conditions. However, there is still a conservation of angular momentum that applies, where air that loses or gains this angular momentum must be exchanging angular momentum with some other air or the Earth itself. Angular momentum can be defined relative to the Earth's axis, in which case it is (per unit mass) equal to: R*cos(latitude) * [ u + OMEGA*R*cos(latitude) ] where R is the radius of the Earth (so R*cos(latitude) is the radius of a latitude circle), OMEGA is the angular frequency of Earth's rotation, u is the zonal wind (relative to the Earth) and OMEGA*R*cos(latitude) is the speed of the surface of the Earth itself in the zonal direction. Generally, on average, Westerly (eastward) angular momentum is lost from the Earth below the atmosphere by friction (and any form drag) acting on tropical trade winds, which then transport that angular momentum upward and poleward in the Hadley cell. Eddy fluxes of angular momentum transport it farther poleward and bring it downward. The Earth gets it back from friction and form drag acting on westerly winds at mid-to-high latitudes. Because the torque of the winds acting on the Earth at any one latitude belt is proportional to the wind stress times the area times the radius of the latitude circle, one or more of the following is necessary for long-term balance - stronger surface mid/high latitude westerlies than low-latitude easterlies, a greater area of mid/high latitude westerlies than low-latitude easterlies, or a greater effective drag acting on mid/high latitude westelies than low-latitude easterlies. I'm not sure if the properties of Rossby waves would tend to create the third condition if all else was equal, but the distribution of mountain ranges would have an effect. This has consequencies for how a steady-state Hadley cell would be sustained in the absence of eddies. Rather than a surface low at the equator and high at the poles with surface easterlies everywhere in between, there would be weaker polar highs or perhaps slight polar lows with midlatitude highs; the high-latitude winds would westerly with a westerly ageostrophic component (supplied from downward transport of momentum, enough to overcome friction even if around a polar low pressure) so that the coriolis force would accelerate the winds equatorward. If there were not a zero net torque, the atmosphere would continually sping up or slow down so as to change the torque until balance were achieved.
130611. Quietman at 06:24 AM on 23 November 2008
        Models are unreliable
        chris disregard that - I misread your statement. I was referring to the last 10 years while you referred to the entire length of the last PDO.
130612. Quietman at 06:22 AM on 23 November 2008
        Models are unreliable
        chris Just a small point re: "3. These (NASA GISS, Hadcrut, NOAA) show long warming trends from the mid 1970's through to the present." In reality only GISS actually shows a slight increase, the others are actually slightly negetive.
130613. LarianLeQuella at 06:16 AM on 23 November 2008
        Other planets are warming
        I suggest that people who think that the sun is responsible, and cite warming on other planets become familiar with the Inverse Square Law. ;)
130614. LarianLeQuella at 06:15 AM on 23 November 2008
        Climate change on Mars
        I suggest that people who think that the sun is responsible, and cite warming on other planets become familiar with the Inverse Square Law. ;)
130615. Quietman at 06:01 AM on 23 November 2008
        Models are unreliable
        Just another modelling error: Global Warming Predictions Are Overestimated, Suggests Study On Black Carbon ScienceDaily (Nov. 19, 2008) — A detailed analysis of black carbon -- the residue of burned organic matter -- in computer climate models suggests that those models may be overestimating global warming predictions.
130616. Dan Pangburn at 17:29 PM on 22 November 2008
        Models are unreliable
        Radiated energy (from all surfaces, including earths) varies as the fourth power of absolute temperature so a temperature down trend is insufficient to prove that net positive feedback does not exist. My bad to have overlooked this before. However, review of temperature during the last and previous glacial periods reveals that the temperature changed from an uptrend to a down trend with the atmospheric carbon dioxide level higher during the down trend than it had been during the uptrend. That could not happen if atmospheric carbon dioxide level increase was a significant driver of average global temperature increase. The present atmospheric carbon dioxide level is somewhat higher than it was during the glacial periods. As Carbon dioxide level increases, each additional increment has less influence than the previous increment. This effect is appropriately called saturation. Thus increased atmospheric carbon dioxide now is even less able to influence temperature than it was during the last glacial period when temperature increasing trend changed to a decreasing trend. The conclusion from all this is that the current rising atmospheric carbon dioxide did not have a significant influence on any temperature rise including the temperature rise from the mid 1970s until about a decade ago and will never be a significant factor in temperature increase. Contrary to Chris’ assertion which was “The major predictor of Anthropogenic Global Warming is our understanding of the greenhouse effect …” the discovery long ago that carbon dioxide and water vapor absorb certain wavelengths of infrared radiation does not mandate that human activity has caused the planet to get significantly warmer. It is pretty widely known that the infrared absorption, mainly by water vapor, helps make the planet have the nominal temperature that it does. It is less widely known that the absorption takes place close to the emitting surface (half within 24 meters as calculated from Barrett’s paper at http://www.warwickhughes.com/papers/barrett_ee05.pdf , others calculate even closer). Adding carbon dioxide to the atmosphere results in the infrared radiation being absorbed a bit closer to the emitting surface. The atoms that absorb the infrared radiation energy nearly all immediately share it by thermal conduction with the much more abundant adjacent atoms that are transparent to infrared radiation. That, for the most part, is what warms the air. The shared energy is then carried up by convection currents. Existing GCMs are unable to objectively account for this natural convection so the process is imposed on the models with a contrived parameterization. Contrary to one of many of Chris’ erroneous assertions, that I have stated that “I am right and everyone else is wrong”, I share the perception with over 31,000 other scientists and engineers at http://www.petitionproject.org/ that human release of carbon dioxide will not cause catastrophic global warming. These scientists and engineers gain nothing for this declaration while the 2500 or so alarmist climatologists must make dire predictions for the government grants to continue.
130617. Patrick 027 at 15:29 PM on 21 November 2008
        Arctic sea ice melt - natural or man-made?
        "the geostrophic wind is non-divergent in isobaric (and also isentropic, I believe) coordinates - the convergent motion may be ageostrophic, and if so, the coriolis force on it is not balanced by the pressure gradient force. This means the coriolis force itself exerts a torque about a center on ageostrophic motions " ... Just to be clear, though - that was just to illustrate one major process; Solving the momentum equations for vorticity yields the more general result that absolute vorticity (RV + f) remains inversely proportional to a horizontal area or the horizontal projection of an isobaric (or isentropic) area enclosed by material lines, which shrinks or grows by horizontal convergence or divergence, respectively, when (the horizontal component of) absolute angular momentum is conserved, which is true, except for: 1. friction or mixing, 2. nonzero solenoidal term (not applicable to isobaric or isentropic coordinates), 3. nonzero tilting/twisting (horizontal variations in vertical momentum transport, which is generally small for larger scale motions and is zero for adiabatic motion in isentropic coordinates), and with the approximation that 4. the coriolis effect acting on vertical motion and causing vertical acceleration is neglible (which is true even for rapid motions in thunderstorms, because with rapid vertical motion, the air (following the air) has to start and stop within a time frame much shorter than the Earth's rotation period, given atmospheric dimensions). 5. the 'curvature terms' are neglible (which is true) - the curvature terms account for the curvature of the Earth; for x,y,z coordinates defined everywhere locally, with x being east, y being north, z being up - moving around involves accelerations of that coordinate system itself; for example, two great circle routes that are not identical inevitably intersect, so in order for two air parcels to remain on parallel trajectories for long distances, there must be some horizontal acceleration on at least one of them... etc. - but that is a small effect. Sometimes factors which absolutely must be included for understanding longer term processes, such as radiative heating and friction, can actually be ignored without losing a basic understanding of some processes that happen over short-enough periods of time.
130618. chris at 09:20 AM on 21 November 2008
        Human CO2 is a tiny % of CO2 emissions
        Not really Mizimi, Let's not get confused by semantics! Playing with words doesn't change reality. A thermostat is effectively a "dynamic equilibrium". Have a think about how a thermostat works to maintain the temperature in a room at an equilibrium temperature.
130619. chris at 08:53 AM on 21 November 2008
        Water vapor is the most powerful greenhouse gas
        Mizimi those numbers are nonsense. I don't believe they're from the IPCC reports at all. Why not simply give us the url from the site that you cut and pasted them from? And how can you say one the one hand that "they ignore WV as a GG"... ...and on the other show data that indicates that water vapour is 94.999% of the whole? ...???????
130620. chris at 08:41 AM on 21 November 2008
        It's Urban Heat Island effect
        re #13 Not really Rob. The oceans are covered rather extensively with a series of ocean surface temperature measures. Desserts don't cover 10% of the Earth's surface. At any one time a tiny proportion of the Earth's surface is covered by desserts. Even if every 280 million US citizens was holding a chocolate fudge sundae or a baked Alaska, this would cover a tiny, tiny proportion of the surface of the USA. The proportion of Africa covered by desserts is tiny, since Africans rarely eat dessert...etc...etc... The fact that Tmin is increasing faster than Tmax is what one expects from greenhouse-induced warming. Remember that the atmospheric warming due to enhanced greenhouse gases results from trapping of longwave infrared radiation emitted from the Earth's surface. While the absorption of solar radiation occurs during the day, the emission of longwave IR occurs during the day and the night. It doesn't stop when the sun stops shining. So it's not unexpected that Tmin should increase faster than Tmax...
130621. chris at 08:33 AM on 21 November 2008
        Temp record is unreliable
        ummmmm Rob.. Since I am quoting Hanson directly from one of his papers, I don't really need to tell him anything. Urban areas are generally warmer than the surrounds. Therefore one either eliminates urban areas from the record to establish the Earth's surface temperature evolution, or one corrects the data from urban stations by reference to local urban stations. However one does this (leaves out the urban stations or corrects these) the Earth's surface temperature anomaly is the pretty much the same. You would benefit from reading John Cook's article on urban heat island effect.
130622. chris at 08:19 AM on 21 November 2008
        Global warming stopped in 1998, 1995, 2002, 2007, 2010, ????
        Re #27 Not really Mizimi. Remember that the effect of a forcing (whether a warming or a cooling forcing) relates to the temperature change at equilibrium.... ...at equilibrium... Note two things about the influence of the solar cycle on the Earth's temperature response: (i) the solar cycle has a rather rapid sinusoidal variation. The entire cycle takes only 11 years to evolve from its maximum TSI to its minimum TSI and back again (ii) The Earth's surface temperature response is damped, and it comes to equilibrium much more slowly than the few years "allowed" for it to "track" the solar cycle variation. So the tracking of the Earth's temperature response to the solar cycle is continuously "frustrated" (very much like the temperature response to a thermostat). The atmosphere follows the solar cycle most faithfully. The ocean and land surface is much slower to respond. So the effects of the solar cycle is damped, and the entire effect of the solar cycle is to contribute around 0.1 oC of temperature difference at the Earth's surface, between the solar maximum and solar minimum (Tung considers that the solar cycle contribution is a bit larger...around 0.18 oC). If the solar cycle were to stop and the sun emit solar radiation equivalent to 1363.5 W/m2 for a long period (say 30 years to come close to equilibrium)...and then the sun switched to a constant TSI output equivalent to 1360.25 W/m2 for 30 years to establish the new equilibrium temperature, the temperature difference at the Earth's surface would be your 0.45-ish oC of cooling (all else being equal). ..but these temperature changes in response to forcings are equilibrium changes..
130623. Mizimi at 05:56 AM on 21 November 2008
        It's Urban Heat Island effect
        Just had a look at the updated satellite composite at Data @ NASA GISS Surface Temperature Analysis Maps.htm (October 2008). Quite a difference to the 2005 composite,a lot more 'colder' areas, especially Antartica, Alaska, North Am,erica and Northern Europe/Greenland.
130624. Patrick 027 at 16:03 PM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        clarification: turbopause ~ 100 km or around there; not to be confuse with tropopause which is 'much closer to home'.
130625. Patrick 027 at 15:59 PM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        Clarification: H escape does not occur directly from all levels above the tropopause - generally it is limited to around 500 km and higher; but H atoms from (photo)dissociated molecules below will diffuse upward due to the removal at higher levels. (without removal, generally, single atoms/ions or smaller (in terms of number of atoms) molecules will diffuse downward while larger molecules/polyatomic ions will diffuse upward because chemical equilibrium by itself favors smaller molecules and single atoms/ions at lower pressures, but diffusion will occur along a non-hydrostatic gradient (above the turbopause, each chemical 'species' acts like an atmosphere unto itself in so far as pressure decline with height being related to density and gravity, density related to pressure by ideal gas law specific to each substance if the gas law is in terms of mass)...
130626. Patrick 027 at 15:49 PM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        Correction: I was refering to 100 Gt (gigaton) of C (is t the correct symbol for ton? - PS I believe these are metric tons - even if they weren't, the numbers wouldn't be much different) of C, which mostly exists as CO2 in the atmosphere, of course. molar mass ratio CO2/C = ~ 44/12 = ~ 3.67 so 100 gigatons C would make 367 gigatons CO2. PS molar mass ratio (average air molecules)/C = ~ 2.42 PS back to angular momentum for me tomorrow or the next day.
130627. Patrick 027 at 15:39 PM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        chris - Thanks for the clarification, I was wondering! -"There is experimental evidence that CO2 is well-mixed vertically throughout the atmosphere ('though I'd have to hunt down the relevant paper(s)). The other means that we know that CO2 is well mixed on annual timescales is that there are is a large number of measuring stations scattered around the remote and isolated regions"... Actually I would like to know more about that - just how close to the surface does one have to get before one finds a diurnal variation of x% or a spatial variation of y ppm/km, etc. (The annual fluxes between the atmosphere and 1.land biota (and soil), 2.the ocean - are about 100 Gigatons and 90 Gigatons, respectively - each to and from, thus no net change, except for an imbalance most likely induced by anthropogenic emissions that removes CO2 from the air (unfortunately not all, nor guaranteed to continue as it has been - biological uptake limited/influenced by climate, attainable tree heights,etc, evolved plant cabilities, ecological interactions (and soil responses), etc, oceanic uptake limited by exchange with the deeper ocean, chemistry, etc - not as simple as just dissolving a gas in water) - and except for geologic emissions, chemical weathering, and organic burial, which are all very small in comparison. Some (most??)of the oceanic fluxes are associated with CO2 release from warmer ocean surfaces and CO2 uptake by colder ocean surfaces. Of course, the seasonal cycle in atmospheric CO2 is, I think, either mostly or entirely due to different seasonal cycles in land biota CO2 uptake and CO2 release. Adding or taking up 1 gigaton of CO2 is about 0.47 ppm change in atmospheric concentration; since the annual variation is quite a bit smaller than 50 ppm we know much of those natural fluxes are going both ways at the same time, at least if averaged over days. If the 100 gigaton addition or removal by land biota occured completely without the other, were concentrated over 10% of the surface (~1/3 land area - that might actually be about true?), and concentrated to 1/3 of the year, then a change per day of 0.4 ppm would occur if the air were stagnant horizontally; 4 ppm per day if only mixed vertically in the bottom 100 mb of air and stagnant horizontally... ) I had found a website showing the CO2 records of the last few-several decades from - I think - 8 stations(including Mauna Loa, and a few from the Southern Hemisphere). I copied and pasted some of graphs into Microsoft Paint files and overlaid them and indeed they match up very well in annual averages. It's also interesting to sea the seasonal cycles, which not surprisingly are largest in northern high latitudes. I'll post that website here if I find it again (it may have been from CDIAC). -"I guess the fact that so much of the earth's hydrogen is "locked up" in water helps to limit its loss" True; I've read that, due to lack of atmospheric oxygen, in the Archean eon, atmospheric CH4 could have built up to levels far beyond what we know; and not condensing befor reaching the tropopause, would have greatly enhanced total H content above that point, thus greatly enhancing H escape to space and - being as (after some evolution of life) most CH4 would have biogenic, and produced from photosynthetic C fixation which split H2O - methanogens and cyanobacteria together thus allowing a net reaction H2O _ 2H + O, O accumulating as H escapes to space. Of course O gets sequestered by ferrous iron in rocks (serpentinization, etc.) and the ocean (BIFs) before finally building up in the atmosphere - and then there is some evidence that over the middle of the Proterozoic, only the upper ocean was oxydized; the oxic atmospheric conditions, etc, affecting the sulfur cycle (I don't know or recall the details of that) so that the deeper ocean water turned sulfidic for several hundred million years before finally turning oxic.... (in case your interested:) 1. "Biogenic Methane, Hydrogen Escape, and the Irreversible Oxidation of Early Earth David C. Catling,12* Kevin J. Zahnle,1 Christopher P. McKay1" http://www.sciencemag.org/cgi/content/abstract/293/5531/839 2. "Proterozoic Ocean Chemistry and Evolution: A Bioinorganic Bridge? A. D. Anbar,1* A. H. Knoll2" http://www.sciencemag.org/cgi/content/abstract/297/5584/1137?ck=nck It's been awhile but I had read the whole of each of those; I've just found some interesting related material: "Molybdenum Isotope Evidence for Widespread Anoxia in Mid-Proterozoic Oceans G. L. Arnold,1* A. D. Anbar,1,2 J. Barling,1 T. W. Lyons3 " http://www.sciencemag.org/cgi/content/abstract/304/5667/87 "Did the Proterozoic 'Canfield Ocean' cause a laughing gas greenhouse? R. BUICK Department of Earth & Space Sciences and Astrobiology Program, University of Washington, Seattle WA 98195-1310, USA" http://www3.interscience.wiley.com/journal/118516679/abstract "Constraints on the Archaean Environment" "Carbon dioxide cycling through the mantle and implications for the climate of ancient Earth Kevin Zahnle1 & Norman H. Sleep2" http://sp.lyellcollection.org/cgi/content/abstract/199/1/231 --- Philippe Chantreau -"I probably have a lot less disposable time than Chris or Patrick for blogging, so I may or may not get to take a look at the papers you link." I haven't looked at any of those papers yet, either - so I've been grateful someone else did!
130628. Philippe Chantreau at 09:41 AM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        Arkadiusz, what I meant was that if a hypothesis relies on data that are not in the real world and physical mechanisms that can not be observed in the real world, then that hypothesis has essentially no existence. It's not like something we don't understand; it's something we don't see directly, or whose indirect effects are not observed either. Even String Theory has more existence than that, since it is consistent with Quantum Theory. Beck says that there has been wild up and down variations of CO2 on short time scales but offers no evidence for it except his measurements in urban areas, which are meaningless, as Chris explained. Cherry picking studies suggesting variations that are very, very far below what's needed for Beck's "hypothesis" does not help. It has dawned on me recently that climate blogging is a very futile exercise in many aspects and I probably have a lot less disposable time than Chris or Patrick for blogging, so I may or may not get to take a look at the papers you link. Got to prioritize, you know. However, I am still very confident that nothing can explain the variations proposed by Beck, because these variations are simply enormous and the time periods too short. Consider the masses of carbon that have to be injected or removed from the all atmosphere (if we are to talk about well mixed CO2, the one that matters to climate) and see if, quantitatively, it can be reconciled. Many scientists study this stuff all the time, it has already been considered. There are no biological mechanisms working such huge changes that fast. In a way, Beck's exercise is supremely ironic. He uses measurements of places where concentrated fossil fuel burning induces very large, very short term, very localized changes and then goes on to propose that the changes we see in CO2 and climate have nothing to do with fossil fuel burning.
130629. chris at 07:41 AM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        Patrick, whoops! I wrote my post too quickly: Referring to Wagner et al's leaf stomatal CO2 paleoproxy, I meant that their atmospheric CO2 levels in the 2000 years between 8600BP and 6700 BP were around 295ppm +/- 10 ppm during this period. I didn't mean to say that they varied by 295 +/- 10 ppm (although that's what I did say)! Apologies for the confusion.. Yes, your comments about greenhouse gas mixing are pretty straightforward. And yes hydrogen does only escape to space significantly on geological timescales, although the absolute rate of loss in terms of tons per year or whatever might seem rather alarming (in the same way that the absolute amount of solar mass consumed in a year also seems alarmingly high!). I guess the fact that so much of the earth's hydrogen is "locked up" in water helps to limit its loss..... There is experimental evidence that CO2 is well-mixed vertically throughout the atmosphere ('though I'd have to hunt down the relevant paper(s)). The other means that we know that CO2 is well mixed on annual timescales is that there are is a large number of measuring stations scattered around the remote and isolated regions and these show a rather close correspondence in measured atmospheric CO2 levels. As you suggest, if one measures environmental CO2 near sources (e.g. in cities) then one can find very high levels that don't represent the global average, and can even measure CO2 values that change wildly between the morning and afternoon, or between windy and windless days.
130630. Patrick 027 at 07:03 AM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        chris - "The effect on the plant stomatal index might have contributions from a temperature response rather than from a drop in atmospheric CO2." I would think it has to have such contributions - a 295 ppm variation over that time period would mean there was negative CO2 (antimatter? :) ) in the atmosphere at some point! (If according to X, A or B is possible, but not C, and according to Y, B or C is possible, but not A, then X+Y = B possible, A and C not possible.) And perhaps a review of what is meant by Well-mixed GHGs: Substances or phases can become well mixed when the time period of mixing is considerably shorter than that of sources and sinks (chemical and/or physical reactions or any other external sources or sinks). Clouds are not well-mixed because cloud droplets and ice crystals are forming, growing, combining, changing into eacher, and precipitating (in some cases evaporating within another air layer) etc, faster then the wind can stir them up (and stirring itself can drive these processes - mixing fog on the one hand, downdrafts from cold dry air impinging on the side of thunderstorm and causing evaporative cooling on the other hand). Water vapor evaporates from wet surfaces and also from haze particles and clouds themselves sometimes and is also removed by condensation. I don't know as much about ozone - my impression is that within the stratosphere it may be regionally mixed but there are still large latitudinal variations at any one time. Ozone of course is produced and consumed by chemical and photochemical reactions (there are, I think, siginificant differences in reaction rates between the troposphere and stratosphere. Perhaps for water vapor, too? - some of the water vapor above the tropopause gets there by oxidation of methane. Anyway...). Aerosols are also not well mixed, although some can linger in the stratosphere once there for a while. CH4 does oxydize over a decade or two, but not fast enough to avoid becoming well-mixed - at least within the troposphere (I'm less clear on upper-atmospheric variations - there are photochemical reactions that can occur a lot more up there, of course - but only H would escape to space significantly, and that's only over geologic time periods, I think (?).). This doesn't mean it's perfectly mixed over the whole air mass. Particularly near the surface, there will be heightenned concentrations near sources and immediately downwind at any given time, and there could be some regional variations. But the larger-horizontal scale variations will be small in proportion to the average. And so on for CO2. There are significant seasonal variations in CO2, but not so much that this is important for climatic effects. Also, GHG variations near surface sources and sinks are less relevant to climate effects because the lower-level air's temperature tends to be close to the surface temperature (except maybe on calm clear nights over land) - and it's only x% of atmospheric mass (~ 6 or 10% if we're discussing atmospheric boundary layer over the whole globe).
130631. chris at 04:54 AM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        Re #333 A couple of other points Arkadiusz: You refer me to two links concerning ice core data. The first one is this: http://www.jennifermarohasy.com/blog/archives/002176.html The second one is this: http://www.realclimate.org/index.php/archives/2007/04/the-lag-between-temp-and-co2/#more-430 The RealClimate link seems entirely satisfactory. It's an excellent account of the ice core data on temperature and CO2 measures during ice age cycles. What point are you trying to make? The second link is to a blog by a certain jennifer marohasy. She seems to be a senior person at a think tank in Australia (Institute of Public Affairs), and produces/disseminates misrepresentations of the science on environmental matters. The Institute of Public Affairs is part funded by irrigation companies, logging/timber companies, cigarette companies, mining companies. In other words she's involved in the sort of attempted misrepresentation of important scientific matters in support of corporate interests. So rather similar to the US "think tanks" that told untruths about the links between ciggie smoking and cancer/respiratory and circulatory disease; untruths about the links between aspirin taking and Reyes syndrome in children; untruths about the links between chlorofluorocarbons and depletion of high atmosphere ozone...and so on. Now you may consider that it's appropriate to misrepresent the science on important issues, so as to benefit particular interests. However, I hope you would recognize that if one wants to understand what the science says/means, these sorts of institutions (and their websites) are dismal sources. One might unfortunately put Jaworowski in a similar "camp". He seems to want to create a false impression of the science on ice cores and paleoproxy CO2 measures. I'd be very interested to know what he thinks will be achieved by trying to cheat us in this way....
130632. Mizimi at 04:35 AM on 20 November 2008
        Global warming stopped in 1998, 1995, 2002, 2007, 2010, ????
        "Alternatively, Camp 2007 adopts an empirical approach to calculate solar influence on global temperature. He determines the solar cycle contributes 0.18°C cooling to global temperatures as the sun moves from maximum to minimum. Employing back of a napkin calculations, TSI would need to fall roughly 4.3 W/m2 to provide 0.6°C of cooling." Isn't this what the graph shows? Lows of around 1360.25 to highs of 1363.5...roughly 3.25W/m2 or around .45C of cooling?
130633. chris at 04:22 AM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        Re #333 Arkadiusz, ONE: plant leaf stomatal index of past CO2 levels. I'm not sure where you get your "..CO2 jumping - even above 100 ppmv by ~ forty - fifty years."! You've brought two stomatal index papers to our attention. These are: F. Wagner et al. (2002) "Rapid atmospheric CO2 changes associated with the 8,200-years-B.P. cooling event" Proc. Natl. Acad. Sci. USA 92, 12011-12014 and: T. B. van Hoof et al (2008) "A role for atmospheric CO2 in preindustrial climate forcing" Proc. Natl. Acad. Sci. USA 105, 15815-15818 In the first one (Wagner et al, 2002) plant leaf stomatal proxy CO2 levels were reconstructed to vary by around 295 +/- 10 ppm over a period of around 2000 years (8700 BP - 6800 BP). That's certainly not consistent with Beck's massive jumps over short periods. In the second one reconstructed atmospheric CO2 levels varied by around +/- 10-15 ppm over a period of around 500 years. So neither of these is really consistent with Beck. One might make the conclusion that the ice core CO2 data is somewhat "smoothed" out by averaging of atmospheric CO2 over a period of several years before the air in the firn is sealed off (see my post #330 above and discussion of formation of polar ice) . However the stomatal index reconstructions don't show wild and massive up and down jumps of atmospheric CO2. One should also be a little careful in assessing the stomatal index CO2 reconstructions. As you may know, the analysis is based on observing the size/number of the stomatal pores in plant leafs, with the assumption that as CO2 levels rise the plants respond by reducing their stomatal pore density (I think that's right!). However there is still quite a bit of controversy amongst the pactitioners themselves as to how reliable the proxy CO2 levels are. If you look at the two papers cited one can see that the error bars are very large (e.g. in the Wagner et al paper they encompass up to almost the entire range of CO2 variation). One might also question whether the stomatal index varies with temperature; e.g. the cold spell near 8200 BP studied by Wagner et al (2002) is though to be due to the collapse of the remnant of the Laurentide ice sheet as part of the late stage of the deglaciation into the Holocene. The effect on the plant stomatal index might have contributions from a temperature response rather than from a drop in atmospheric CO2. But whatever the relatively small disagreement between the stomatal plant proxies for CO2 and the ice core measures, all of the paleoproxy reconstructions of atmopsheric CO2 show reasonably steady CO2 levels before the preindustrial age. They certainly don't display "Beck-style" massive up and down jumps. And of course we know exactly why Beck's "analysis" shows massive up and down jumps. Much of the data he presents is from data measured in cities. If one looks a some of the original papers that Beck trawls through for his "analysis" one finds that "atmospheric CO2 levels" jump by 40 ppm from the morning to the afternoon, for example. That's what happens in cities! We don't need to pretend to be taken in by Beck's ludicrous misrepresentation. A more detailed critique is described here (see post #172): http://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm TWO: historical paleotemperatures in Fontainebleau. I don't see your point in directing us to this paper. It seems a nice paper: i.e. N. Etien et al. (2008) "A bi-proxy reconstruction of Fontainebleau (France) growing season temperature from A.D. 1596 to 2000" Clim. Past, 4, 91-106 It shows a very typical proxy temperature evolution over the last 140 years that indicates that the region of Fontainebleau in France is warmer now than it's been in the past. As the authors conclude their abstract: "The persistency of the late 20th century warming trend appears unprecedented." What did you consider significant? The delta 13C spikes that you note are not necessarily very significant. Again the authors state that one needs to be careful in interpreting delta 13C data from timber; they say: "...This argument acts against the use of delta-13C measurements for long term temperature reconstructions despite the fact that it can slightly improve reconstructions for the 20th century." Again, this paper seems entirely consistent with our understanding of the climate in Europe during the last 200 years. It doesn't really bear on Becks nonsensical analysis at all. Remember that when we are considering atmospheric CO2 concentrations we are interested in the globally averaged levels, and aren't interested in the sort of local effects that make Beck's analysis completely useless.
130634. Arkadiusz Semczyszak at 00:09 AM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        Chris OK by Drake Chris Sorry about 230 instead 320 - these literals errors - it’s may frequent mistake. “The data are very noisy with large errror bars” - ice core only error bars, but too very large error - Chris, You known discussion by: http://www.jennifermarohasy.com/blog/archives/002176.html , and http://www.realclimate.org/index.php/archives/2007/04/the-lag-between-temp-and-co2/#more-430 “poor master Beck”? What about big maximum δ13C ~1730 in France (Fonteinblau ) and two maximum ~1950 years? What about stomatal index, C4 index?, these is indicate on a CO2 jumping - even above 100 ppmv by ~ forty - fifty years ! “poor” it’s only We (1% global product We must pay whit humbug AGW - Stern rapport) Philippe Chantreau I’m propose You on first: http://www.biokurs.de/treibhaus/180CO2/180CO2-D.pdf - here is reply of comments by H. Meijer, by R. Keeling. “nowhere to be found in Nature” - if We don’t understand it - not explain - it’s not exist? I’m suggested: - grassland - You mast reading - Global Change: Effects on Coniferous Forests and Grasslands (Breymeyer et al 1996) especially tropical pampas - they has very different NPP and very high soil, detritus, humus accumulations… (soil I think, it’s don’t appreciate the source and sink Beck’s CO2 - remind you for example ‘Biosphere 2’ experiments) - coccolith maybe same one coral - read for example early comment at “Phytoplankton Calcification in -CO2 World” ; and particularly: Macedo, MF, Duarte, P., Mendes, P. and Ferreira, G. 2001. Annual variation of environmental variables, phytoplankton species composition and photosynthetic parameters in a coastal lagoon. Journal of Plankton Research 23 : 719-732. Macedo, MF, Duarte, P., Mendes, and P. Ferreira, G. 2001. and Trichodesmium, Montastraea cavernosa, denitrification bacterial - in High CO2 - acid sea atmospheric N2 assimilations - coccolith and coral relationship... You must it known… …too match subject by this post…
130635. Philippe Chantreau at 19:26 PM on 19 November 2008
        Arctic sea ice melt - natural or man-made?
        Beck's take on wild CO2 variations is ludicrous. Not only it's not there in the data but his proposed mechanisms (biomass) to explain it are nowhere to be found in Nature.
130636. Philippe Chantreau at 18:59 PM on 19 November 2008
        Arctic sea ice melt - natural or man-made?
        Beck's take on wild CO2 variations is ludicrous. Not only it's not there in the data but his proposed mechanisms (biomass) to explain it are nowhere to be found in Nature.
130637. chris at 11:31 AM on 19 November 2008
        Arctic sea ice melt - natural or man-made?
        Re #324/328/329 Becks analysis is clearly rubbish. See for example: http://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm (see post #172) And of course the links that Arkadiusz cites in his posts don't support Beck at all (Beck's a schoolteatcher btw). For example: ONE: Arkadiusz suggests we look at Phytoplankton Calcification in a High-CO2 World” : M. D. Iglesias-Rodriguez, et al. Science 320, 336-340,2008 (note that the volume number is 320 not 230) The data is summarized in Figure 4 of that paper which shows average coccolithophore mass as a function of time during the last couple of hundred years; high mass is proposed to correlate with high CO2 concentrations. The data are very noisy with large errror bars, but the smoothed fit matches very well with the atmospheric CO2 data from the Siple ice core, and (since 1959) with the Mauna Loa observatory data. In other words the paper is entirely inconsistent with Becks ludicrous "analysis" of CO2 levels jumping up and down wildly during the 20th century, and entirely consistent with the high resolution atmospheric CO2 record from Mauna Loa and ice cores. TWO: Arkadiusz suggests we look at a truly harebrained "analysis" of ice core CO2 data from the Fuji Dome core in Antarctica on some person's website ("JJ Drake"). Let's first of all take the nonsense presented there at face value. Does it support Beck's attempt at pretending that atmospheric CO2 levels jump up and down all over the place by vast amounts in very short periods? Not really. JJ Drake's "analysis" artefactually smooths out the atmospheric CO2 record of around 400,000 years such that it is largely constrained in a tightish band near 325 ppm (keep this number in your mind for later). So that's also entirely inconsistent with Becks notion of massive jumps up and down in atmospheric CO2 levels. It's worth pointing out the blatant error in "JJ Drake"'s "analysis". JJD has ignored his own mantra (see top of page of his website) that "Correlation is not Causation", and pretended that a correlation is a causation. Here's the problem: JJD has noticed a Figure (Figure 2) in a paper in which the Antarctic Fuji Dome core CO2 record is described: K. Kawamura et al. (2003) "Atmospheric CO2 variations over the last three glacial–interglacial climatic cycles deduced from the Dome Fuji deep ice core, Antarctica using a wet extraction technique" Tellus B 55, Issue 2, Pages 126-137 In the Figure (reproduced in JJDrake's website that Arkadiusz Semczyszak links to in post #329), the trapped CO2 concentrations are plotted as a function of time, and show the very nice glacial/interglacial record observed in all of the cores from Antarctica and Greenland. Also plotted is the difference in age between the ice and the trapped gas (dIG = delta ice/gas) as a function of time through the core. JJDrake notices that there is a correlation. If one plots the dIG as a function of measured [CO2] one gets a reasonable straight line that extrapolates back to 325 ppm at dIG=0 (remember that number from above?). JJDrake then attributes a spurious cause to to this correlation, namely that the CO2 somehow disappears/is destroyed from the trapped ice, and the rate of this disappearance is proportional to the age diference between the ice and the trapped air. Is there any physical/chemical basis for this assumption? JJDrake doesn't give us any. And what's the effect of "compensating" the ice core record by assuming Drake's fictitious non-defined causal relationship between dIG and magical disappearance of CO2? It effectively smooths out the record so that the CO2 concentrations are pretty close to 325 ppm for the past 400,000 years. O.K that's pretty silly. But do we know why there is a correlation between the atmospheric CO2 levels in the core and the dIG value (remember dIG is delta-ice/gas, the difference in age between the gas trapped in the core and the surrounding ice)? Yes, of course. We just need to read Kawamura et al (2003), the very nice paper that "JJDrake" has attempted to trash: It's very well known, since this can be measured directly in newly forming polar ice, that there is a time delay between snow deposition and the sealing off of the air that circulates through the loosely packed new snow that is in the process of becoming ice (called "firn"). Thus the ice is a bit (sometimes a lot) older than the trapped air bubbles within it. If snow is deposited quickly, then in general the air circulating through the firn and equilibrating with the atmosphere is trapped relatively quickly, and there isn't much difference between the age of the air and the age of the surrounding ice (in a core, for example). And vice versa. In Antarctica snow deposition is slow (allowing very long time period cores to be drilled), and so the dIG values are in general large. Remember that the rate of snow deposition is a major factor in determining the dIG value. When is snow deposition in the Antarctic fastish? It's during warm periods when atmospheric moisture levels are higher. So when it's warmer (interglacials) the firn seals off more quickly and the dIG value is smaller. During glacial periods the atmosphere is much colder, the air is dryer, snow deposition is very much slower, the firn seals off much more slowly, and so the air in the firn equilibrates with the atmosphere for much longer periods and is therefore much "younger" than the surrounding ice when it is eventually trapped...dIG is larger. So the correlation does have a causation. If JJDrake had bothered to read the paper rather than just cut and pasted a Figure from it, he wouldn't have made such a dull blunder... and so on. We could have a look at a few more of Arkadiusz Semczyszak's "links" and see whether any of thoe others supports poor master Beck!
130638. Mizimi at 05:43 AM on 19 November 2008
        Water vapor is the most powerful greenhouse gas
        Apologies for the format, the spaces that should have been there seem to have been ignored in uploading. try again: The figures given indicate the relative contribution of GG's to global warming as a % of the whole, ie +33C WV from natural sources 94.999%: manmade 0.001% CO2 from natural sources 3.502%: manmade 0.117% CH4 from natural sources 0.294%; manmade 0.066% NO2 from natural sources 0.903%: manmade 0.047% Rest ....................0.025%: manmade 0.047% The basic data is available from the DOE website ( other than they ignore WV as a GG) "Current Greenhouse Gas Concentrations"; " Greenhouse Gases and Global Warming Potentials" From the IPCC "Warming Potentials of Halocarbons and Greenhouses Gases"
130639. Mizimi at 05:09 AM on 19 November 2008
        Human CO2 is a tiny % of CO2 emissions
        Dynamic: Characterized by continuous change, activity, or progress: a state of non-equilibrium. Equilibrium: . A condition in which all acting influences are canceled by others, resulting in a stable, balanced, or unchanging system. 'Dynamic equilibrium' is thus an oxymoron. Climate is a dynamic system and fluctuates,(sometimes quite severely as history shows)and for man's purposes we would like those fluctuations to be constrained within certain limits. To my knowledge, nobody has defined what those limits should be. (??) Neither do we have the ability to alter in any meaningful and expiditious way the major active components in the system without causing ourselves serious economic problems....it will be interesting to see what effect the current global economic crisis has on fossil fuel consumption, CO2 concentrations and GMT.
130640. Arkadiusz Semczyszak at 19:49 PM on 18 November 2008
        Arctic sea ice melt - natural or man-made?
        Philippe Chantreau Beck is no "professor." = he’s not right? Harro Meijer and Ralph Keeling having betters arguments… I propose you - Yet see else only: http://homepage.ntlworld.com/jdrake/Questioning_Climate/userfiles/Ice-core_corrections_report_1.pdf I don’t agree with everything what is in this paper, but it’s interesting and I think very important in the IV report IPCC context.
130641. Quietman at 14:50 PM on 18 November 2008
        Arctic sea ice melt - natural or man-made?
        Philippe Re: Beck is no "professor." Nit picking. The papers linked do support Beck.
130642. Quietman at 14:47 PM on 18 November 2008
        Arctic sea ice melt - natural or man-made?
        Arkadiusz Thank you for the links.
130643. rob at 11:36 AM on 18 November 2008
        Temp record is unreliable
        Chris said, Notice that one doesn't need a huge number of "temperature recording stations" to assess changes in global temperature. Now I am glad she mentions this, there are enough rural sites certainly in the US that will give complete coverage, these rural sites show NO significant warming since 1900. Because of this problem (no warming) Hanson/Giss use over 1100 US weather stations many urban so they can then manipulate the raw data to push their cause. http://www.youtube.com/watch?v=LcsvaCPYgcI http://www.climateaudit.org/?p=1859 http://www.climateaudit.org/wp-content/uploads/2007/08/peters27.gif Chris says, So one needs to be clear about what the surface temperature anomaly means and how this is determined before attempting to trash it! [you might read the relevant descriptive papers here [*****]. Notice that in relation to the subject of this thread, the Earth's temperature anomaly progression under the influence of a marked 20th (and especially late-20th) century warming is essentially UNCHANGED if the ENTIRE SET OF URBAN STATIONS IS OMITTED from the analysis. Fortunately, there are FAR MORE RURAL stations than urban stations, so it is NOT ESSENTIAL to employ the urban data in analysis of global temperature change.”] So the "urban heat island effect" is somewhat of a red herring (or a stalking horse) in the context of global temperature anomaly measures. I SAY PERHAPS CHRIS SHOULD TELL HANSON THAT. PERHAPS CHRIS CAN INFORM US WHY HANSON USES STATION PAIRS INSTEAD OF USING THE PRISTINE RURAL STATION DATA ALONE THAT IS READILY AVAILABLE OVER THE ENTIRE GLOBE. Station pairs disguise the actual temperature, by suggesting in flawed studies that there is little UHI effect, try London 9 degree C difference and every other major cities and towns on the planet. Google population growth and the UHI effect, 9 degrees C is NOT high.
130644. rob at 10:44 AM on 18 November 2008
        It's Urban Heat Island effect
        Chris says, One only needs to inspect the global surface temperature anomaly image with a reasonably informed understanding of human population geography to see that the urban heat effects can't have made significant contribution to global surface warming... Well err Chris, oceans cover about 73% of the planet, not many weather stations there, I believe the desserts cover another 10%, not many there either. The majority of the weather stations were and still are situated in the northern hemisphere and this is exactly where most of the cities are located. Google UHI and population growth and see what you get. The other point Chris is that rural sites show little or no warming. Ask yourself why on earth Hanson/giss would want to compare pristine rural data with dodgy urban sites then use iffy and secret algorithms to try to extract the UHI effect out of the urban data when they have the rural pristine data in the first place, odd that. Also ask yourself why T min is increasing at double the rate of T max, I don`t believe the sun shines at night. Have an honest debate, visit climate audit and wattsupwiththat you lean something to your advantage.
130645. chris at 07:25 AM on 18 November 2008
        It's the sun
        Re #215 A scientist can call himself all sorts of things. Spencer is listed under "Staff" at the Earth System Science Center at the University of Alabama at Huntsville. He may consider himself to be a Meteorologist or a Climatologist, and no doubt an Atmospheric Physicist and so on...it doesn't really matter....scientists consider all sorts of different labels to be appropriate to their jobs/expertise. The salient point is that he's made a dreadful hash of analyzing the satellite MSU data for a very long period indeed, his "efforts" have had to be consistently corrected in the scientific literature, and he has taken to bypassing the normal scientific channels and engaged in attempting to sell nonsense to the general public via dodgy websites and suchlike! I've had a look at the paper you've linked to...if I have time I'll make some comments on the PDO thread where you posted the link....
130646. chris at 06:53 AM on 18 November 2008
        It's the sun
        Re #216 ONE: CO2/temperature correlations: I don't think that's correct WA. The paleorecord shows a rather good correspondence between paleoproxies for cold/warm periods and paleoproxies for low/high CO2. Which particular study/geological period were you thinking of? This subject has recently been very comprehensively reviewed by Royer, and a great slew of data highlights the strong relationship between paleoCO2 and paleo temp (high CO2 corresponds to warm periods and vice versa) right throughout the Phanerozoic (last 460-ish million years). I've reproduced citations to a number of these studies at the bottom of the post. Here's Royer's compilation: D.L. Royer (2006) "CO2-forced climate thresholds during the Phanerozoic" Geochim. Cosmochim. Acta 70, 5665-5675. TWO: CO2/temp relationships during ice age cycles. I'm surprised people are still confused by this very straightforward topic. John Cook has explained this very concisely here: http://www.skepticalscience.com/co2-lags-temperature.htm In a nutshell: CO2 is a greenhouse gas. Raising its atmospheric concentration results in enhanced warming of the Earth, all else being equal. A large amount of scientific data, indicates that the Earth's surface temperature responds to enhanced [CO2] with somewhere around 3 oC of warming (+/- a bit) per doubling of atmospheric CO2: http://www.skepticalscience.com/climate-sensitivity.htm It doesn't matter what caused/causes the enhanced CO2; raising [CO2] results in enhanced greenhouse warming. Compare the ice age glacial/interglacial transitions, and the current global warming: a.) ice-age transitions: Over a period of around 5000 years (around 15,000 to 10,000 years ago), predictable changes in the Earth's orbital properties changed the insolation pattern resulting in a very slow warming, and the earth transited from a glacial to the interglacial period that we now inhabit. Over a period of 5000 years the Earth warmed by around 6 oC overall, and during this period atmospheric CO2 levels rose by 90-100 ppm (from 180-270ish ppm) due probably to very, very slow temperature dependent efflux from warming oceans. The temperature rose around 0.1 oC per 100 years on average, with around 2 ppm of raised [CO2] per 100 years. The raised CO2 lagged the warming initially, but it contributed overall to the net warming, since raised CO2 "traps" more solar energy. b. current global warming: At present the Earth is warming at 0.18-0.2 oC per decade (around 18-20 times faster than during the glacial to interglacial), in response to [CO2] that is rising by around 2.5 ppm PER YEAR (more than 100 times faster than during the glacial to interglacial transition). In each case the enhanced [CO2] results in warming. During the ice age cycles, CO2 rose extremely slowly in response to slow Milankovitch-induce warming, and produced a feedback amplification of the initial warming. Now the CO2 is being released directly into the atmosphere in copious amounts at a massive rate. It doesn't matter how the [CO2] gets into the atmosphere...the Earth warms as a result. CO2 is a greenhouse gas. THREE: Satellite record: The satellite record is pretty much consistent with expectations based on our understanding of the greenhouse effect. Unfortunately the record is not very well constrained (it's also very short...since 1979 only). Roy Spencer has made a dreadful hash of "analyzing" the record over a period of nearly 20 years, but others have corrected a number of dreadful blunders, and there doesn't seem to be any substantive disagreement between the record and the expectations from surface warming combined with our understanding of atmospheric physics and thermodynamics. Which papers were you thinking of that "suggest the "fingerprint" is wrong"? FOUR: warming at night..at the poles...in the stratosphere. Which models are you thinking of specifically? It was prediced as long ago as the early 1980's, that warming in response to enhanced greenhouse gases should be most dramatic in the high Northern latitudes and that the Antarctic would remain "buffered" from the effects of enhanced greenhouse gases for some time. That's certainly turned out to be true. I'm not sure about the day/night expectations, although it seems reasonable that greenhose warming would certainly be effective at night. What's your evidence for a disagrement if you considerone exists? I'm skeptical about your point about the "stratosphere"! Evidence please. I wonder if you meant "troposphere"... ----------------------------------------------------- In relation to point ONE above, more recent studies supplement the information in Royers compilation and cover additional periods with new data sets right through the past several hundreds of millions of years: R.E. Carne, J.M. Eiler, J. Veizer et al (2007) "Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era" Nature 449, 198-202 W. M. Kurschner et al (2008) “The impact of Miocene atmospheric carbon dioxide fluctuations on climate and the evolution of the terrestrial ecosystem” Proc. Natl. Acad. Sci. USA 105, 499-453. D. L. Royer (2008) “Linkages between CO2, climate, and evolution in deep time” Proc. Natl Acad. Sci. USA 105, 407-408 Zachos JC (2008) “An early Cenozoic perspective on greenhouse warming and carbon-cycle dynamics” Nature 451, 279-283. Doney SC et al (2007) “Carbon and climate system coupling on timescales from the Precambrian to the Anthropocene” Ann. Rev. Environ. Resources 32, 31-66. Horton DE et al (2007) “Orbital and CO2 forcing of late Paleozoic continental ice sheets” Geophys. Res. Lett. L19708 (Oct. 11 2007). B. J. Fletcher et al. (2008) “Atmospheric carbon dioxide linked with Mesozoic and early Cenozoic climate change” Nature Geoscience 1, 43-48.
130647. Wondering Aloud at 05:57 AM on 18 November 2008
        It's the sun
        172 chris The paleo record shows high CO2 during cold eras low CO2 during warm periods, in short No connection. Even the record that is supposedly the great proof of the concept, from ice cores clearly shows that for the recent past temperatures rise first followed by CO2 increasing. Which is simple to explain with equilibrium chemistry. This is what I was referring to by the paleo record not supporting CO2 as a primary driver. John may well be right and there is some delay mechanism followed by CO2 increasing the warming but this is, if true, at most secondary in the paleo record. As to the satellite record and warming of your later comment, there is much discussion of what the supposed pattern of that warming should be. I am not familiar enough with your cited paper to know what it finds but as others have pointed out above there are a number of papers that suggest the "fingerprint" is wrong. In the past we have handled this by changing what we think the fingerprint should be, correctly or incorrectly I don't know. Remember when models showed the warming would occur first and most dramtically at night and at the poles and that it would be greater in the stratosphere? Two examples of "definite fingerprints" of AGW that made great sense but, didn't work out?
130648. Mizimi at 05:01 AM on 18 November 2008
        It's Urban Heat Island effect
        A passing thought...what data set is the temp anomoly based on? Is it raw data or the data compiled AFTER removing UHI effects? Be nice to know..........
130649. Quietman at 03:44 AM on 18 November 2008
        It's the sun
        chris According to spencer he is a meteorologist. I posted a link to his latest article in the PDO thread.
130650. Patrick 027 at 16:03 PM on 17 November 2008
        Arctic sea ice melt - natural or man-made?
        Clarification: Conservation of (Angular) momentum. It may have seemed a bit abstract, even if well reasoned, to assert conservation of angular momentum in the absence of torque and use this principle to guide understanding of fluid motions, and additionally to include planetary vorticity. Point 1. Illustration of the link between angular momentum and linear momentum. Suppose two balls are rolling past each other as if on different parallel tracks. Picking an inertial (non-acceleration - this also means not rotating) reference frame that follows the center of mass of the system of balls. Thus, it can be seen that both balls are either approaching the origin and each other, or moving away from the origin and also each other. Add a force on each ball such that there is no torque on the system of balls. For just two balls (or any combination of two groups that make up the whole), this requires the 'line of action' of the force acting on both pass through the center of mass. If there is a net force on the system, the center of mass of the whole system accelerates, but provided there is no torque on the system, a system-centered reference frame can be allowed to accelerate such that there is no net apparent force. In that case the sum of all forces is zero - for just two balls, it is as if the balls either repel or attract each other with equal and opposite forces. The angular momentum is the equal to the cross product of the position vector times the mass times the velocity vector for each ball, where the position vector is from the origin (the center of mass of the two balls) - a vector that points from (0,0,0) to the ball. Notice that for two balls on parallel paths, this is equal to the cross product of the shortest vector from one path to the other times the linear momentum of the ball on the second path (it doesn't matter which path and which ball - the two vectors between paths are equal and opposite, as are (in the given reference frame) the two linear momenta. If the balls are rolling towards each other and they are then pulled toward each other, they accelerate, so that they gain some velocity in rolling toward each other in the direction they were going while at the same time they change directions (the component of acceleration perpendicular to velocity) so that (after any given length of time) they now roll faster towards each other on different paths that are closer together. The physics works out such that the distance between paths and momentum along them are inversely proportional, thus keeping the angular momentum constant. On the other hand, if an attractive force between the balls is applied after their closest approach, so that they are moving away from each other, then initially the paths will move farther apart while the motion slows down; the two changes again are inversely proportional. And so on for repulsion. For balls moving along a circle, forces on the balls toward or away from the center of the circle will cause spiralling in or out - but steady circular motion is itself acceleration toward the center; thus pulling toward the center causes increased speed while shrinking the radius; pushing out slows down speed while enlarging the radius, etc. And on a rotating planet? 1. First, you may have wondered - why not just conserve the total angular momentum - as a vector quantity - while moving about? For example, planetary vorticity and thus the planetary angular momentum as vectors are parallel to the Earth's axis (and point North - 'right hand rule'); in the former discussion what was often mentioned was the local vertical component of those things. While in general the vertical component of a torque vector (acting on the angular momentum of horizontal motion) is relatively small for larger-scale motions, torques with other components can be important. If rotating air, including it's rotation aquired from the rotating Earth beneath it, is carried to some other latitude, a gyroscopic effect would tend to keep it oriented as it was, rather then bending with the curve of the Earth. (There are actually vertical accelerations associated with the coriolis effect.) Two vertical forces are very strong - gravity and the counterbalancing vertical pressure gradient force are just about equal, and they dominant well above everything else, except for some smaller-scale forces such as rapid updrafts in strong thunderstorms whose accelerations balance an otherwise imbalance in vertical forces - anyway, these vertical forces easily keep the air lying flat or on isentropic or other surfaces whose slopes are determined mainly by other processes. The local vertical component of the absolute (relative + planetary) angular momentum vector can thus be conserved (absent other torques) even as the direction of vertical changes going around the Earth. 2. The conservation of angular momentum associated with planetary vorticity f can be illustrated as follows: if there is a ring of air and that ring is then brought in toward it's center (convergence) - note that except for a beta effect (df/dy not equal to 0), the geostrophic wind is non-divergent in isobaric (and also isentropic, I believe) coordinates - the convergent motion may be ageostrophic, and if so, the coriolis force on it is not balanced by the pressure gradient force. This means the coriolis force itself exerts a torque about a center on ageostrophic motions that are toward or away from that center, thus changing the relative angular momentum - but conserving the absolute (relative + planetary) angular momentum. (This torque is not typically labelled as a torque in equations because the vorticity equations are written with the sum of f and RV. If it is to be regarded as a torque, it is an important torque; otherwise there are not generally any such important torques acting on large scale quasi-horizontal motions (except friction near the surface)). Specifically, the coriolis acceleration's magnitude = f*u, where u is wind speed. Acceleration over time produces a change in velocity; wind speed u over time produces a displacement. Thus an 'ageostrophic displacement' produces a a change in velocity proportional to the displacement times f. Which brings us to 'absolute momentum'...

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