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Comments 131101 to 131150:

131101. Patrick 027 at 10:44 AM on 21 September 2008
        Volcanoes emit more CO2 than humans
        ... Actually the climate forcing due to a 1% change in solar TSI would be closer to 2.4 W/m2. And while solar TSI may often go up and down by 0.1% or something like that, a change of 1% would be more likely over ~ 100 million years, associated with the long-term solar brightenning over it's stellar lifespan. (A formula for solar TSI as a fraction of the present day value is 1/(1 - 0.38*t/4.55), where t is the number of billions of years from now, negative for in the past. This is an approximation that may be innaccurate for near the beginning or end of the solar lifespan - I got it from a paper by James Kasting, forgot which paper. From this formula, solar TSI as a percent of present day solar TSI: 75.0 % at 4 Ga (billion years ago) 80.0 % at 3 Ga 82.7 % at 2.5 Ga 85.7 % at 2 Ga 88.9 % at 1.5 Ga 92.3 % at 1 Ga 93.0 % at 900 million years ago (Ma) 93.7 % at 800 Ma 94.5 % at 700 Ma 95.2 % at 600 Ma 96.0 % at 500 Ma 96.8 % at 400 Ma 97.6 % at 300 Ma 98.0 % at 250 Ma (~Paleozoic/Mesozoic boundary) 98.4 % at 200 Ma 99.2 % at 100 Ma 99.6 % at 50 Ma ... and in the future: 104.4 % in 500 million years 109.1 % in 1 billion years 120.1 % in 2 billion years ---------- And 'wobbles' in mantle convection and continental drift - these wobbles are analogous to day-to-day weather changes in the atmosphere; it is mantle weather. The weather reshapes itself in (depending on the weather features in question - I'm thinking of midlatitude synoptic-scale features) days as the winds reshape the pressure variations (depending in part on temperature variations) that shape the winds. In the mantle, momentum (and therefore the coriolis effect) is negligible; pressure gradients (due to density variations) drive motion against friction. The density variations that force the motion cannot change much faster than the motion itself - thermal diffusion being a much slower process. So large rapid changes in mantle convection and continental drift don't happen. But over many millions of years, the mantle and lithospheric weather will change; as cold slabs of material descend down from subduction zones, continents collide, and material is no longer fed to the descending slab, while the remaining slab continues descent; as continents overide midoceanic ridges; as heat builds up within the mantle near the core or perhaps around pieces of recycled crust to produce buoyant plumes, and as heat builds up under supercontinents, and as continents rift apart and sink a bit. Continents individually are warped and tilted, rise, and sink, as the move over density variations in the underlying mantle (a slow process). Over a long time, one might define a mantle climate. One kind of mantle climate change could then be the transition from layered convection to whole mantle convection. Whole mantle convection is simply convection cells with updrafts and downdrafts extending from top to bottom. In layered convection, the mantle would convect in two seperate layers (boundary at about 660 km depth from surface). When there is a boundary to convection (the top of the mantle, the bottom of the mantle, the bottom of the outer core, and possibly at 660 km depth in the mantle), heat must be transported by conduction to the next layer, which requires a higher thermal gradient, so heat can build up in the lower layer relative to the upper layer. Why would there be two layers of convection? As pressure increases with depth, material is compressed; this is associated with an adiabatic lapse rate where temperature rises or falls within a mass without the conduction of heat. But in solids there can also be phase transitions (I've also heard of different liquid phases of the same substance but ...). As with the phase transitions of melting/freezing and evaporation/condensation, a solid phase transition may involve a change in heat as well as density. Obviously as pressure increases, phase transitions to higher-density phases are favored. If a phase transition gives off latent heat (like condensing of water vapor to form clouds), than that transition will occur 'sooner' at lower temperature - more specifically, the Clapeyron slope dp/dT = change in entropy / change in volume, where dp is the change in pressure of an equilibrium phase transformation with a change in temperature dT. There are multiple phase transitions within the mantle from about 410 to about 660 km from the surface. The Clapeyron slope of the 660 km phase transition (which, going down, involves a change of much of the mantle's material to a perovskite crystal structure) 660 km is a nominal position used for identification - the actual position varies) is negative, which means that at higher temperature, the phase transition occurs at lower pressure. Without phase transitions and in the absence of significant coriolis effect, warmer material at a given pressure will generally rise and colder material will sink due to the effect of temperature on density. But as warmer or colder material rises or sinks across the 660 km phase transition, the actual position will rise or fall, respectively, due to the temperature change, and this produces a density variation that is opposite that caused by the temperature variation, and if strong enough, will produce a force that prevents convection across the boundary. From what I have read (not much, really), I've gotten the impression that there is some layered convection and some whole mantle convection at present; earlier in Earth's history, there may have been mainly just two-layered convection, and perhaps changing conditions caused a transition toward some whole mantle convection around the time of the Archean-Proterozoic transition (?)... Why would that happen? - well, material properties change with changing temperature; as the mantle as a whole cools, the 660 km transition should gradually rise upward overall - in the future, if it goes far enough, it would catch up with other phase transitions (which, if they have positive Clapeyron slopes, would be moving downward - where they meet I would expect a new phase transition to occure with an intermediate Clapeyron slope) ... not all of the mantle substance actually goes into the perovskite structure, ... the overall viscosity increases over time with decreasing temperature overall ... layered convection would allow heat buildup in the lower mantle relative to the upper mantle, so perhaps the temperature difference could have become so great that eventually it overcame the impediment to whole-mantle convection ? - if that's how it works, then one would expect episodic whole mantle convection, after each episode of which, the temperature change with depth would be reduced and so one would go back to two-layer convection - but I'm not sure that's how it would have worked - anyway, the advent of whole mantle convection could then have increased the cooling of the core, which would affect inner core growth rate (ps that liberates latent as well as buoyant composition variations, which help drive outer core convection, which of coarse powers the magnetic field), and this could also affect the geochemistry of the layers and the crust (?)... BUT also so far I have been describing phase transformations as being at equilibrium, but particularly in colder material, it isn't so easy for atoms to rearrange themselves, so phase transformations can be delayed beyond equilibrium, and the resulting microstructure that results when the phase transformation finally occurs can affect the viscosity (and/or rigidity?) of the material, and this would apply to the behavior of cold descending slabs coming from subduction zones. The rate of subduction affects the temperature of the slab, which affects the position and result of phase transformation, the effect on rigidity, and that could affect whether or not the descending slab penetrates into the lower mantle or comes to rest on the 660 km boundary ... SEE Karato, "The Dynamic Structure of the Deep Earth" --- 5. "We almost went extinct once already" Would you be refering to the supereruption of Toba about 75,000 years ago? While it did occur as an ice age was starting or setting in or growing stronger, a supereruption's effects would be particularly sudden, and eventually would have subsided into the background as Milankovitch forcing went on - of course there would be some climatic inertia from any buildup of snow/ice during the cooling from the supereruption. A supereruption, as with single eruptions and earthquakes, etc, are episodic events, and takent one at a time, not necessarily indicative of any overall trend in continental drift, mantle convection, or geothermal heat fluxes.
131102. chris at 10:39 AM on 21 September 2008
        Arctic sea ice melt - natural or man-made?
        Re #223 Mizimi This doesn't make any sense: ["In any event, melting sea ice = drop in ocean temp - more biomass (plankton like it cool) = more sequestration of CO2 and so we go round again. The system as a whole has numerous ways to address imbalances as it has (successfully)in the past."] No...and one can't make up fanciful, simplistic and physically-unviable ladybird book notions as explanations of real world phenomena. Global warming results in WARMING of the oceans AND MELTING of land ice (mountain glacial and ice sheet ice). If you think that warming-induced melting of land ice results in ocean cooling and more biomass and sequestration of CO2, then you are sorely deluded (or just haven't bothered to think properly). Have a think about what processes occurred during the last glacial to interglacial transition as a result of enhanced absorption of solar energy due to Milankovitch cycles, for example. You'll find that the massive amounts of land ice melt (enough to raise sea levels by over 100 metres) during the last glacial to (our present) interglacial transition, 20,000-8000 years ago was accompanied by a warming of the oceans. Let's not pretend that we don't know what we do know. Notice that the "system" doesn't really "have numerous ways to address imbalances". The "system" responds to imbalances in the global heat budget (e.g. by changes in direct solar insolation or enhanced greenhouse gas concentrations) by settling towards a new equilibrium temperature. We can see this very clearly by addressing what has happened in the past. That's the problem. There's no evidence that the Earth has any particular "self-regulating" properties outwith the massive thermal intertial provided by the oceans. So as solar insolation (Milankovitch-induced) or greenhouse gas concentrations increases, so does the Earth's temperature.
131103. chris at 07:42 AM on 21 September 2008
        Arctic sea ice melt - natural or man-made?
        Re #240 Mizimi As Philippe has already indicated, you've posted links to a series of either non-science "sources", or have misinterpreted the science sources you've sourced. For example, on the effects of greenhouse gas emissions on plant growth and CO2 sequestration by the terrestrial environment, it's very clear that the massively enhanced CO2 emissions, especially during the last 30-odd years have decidedly NOT seen enhanced terrestrial absorption via enhanced plant growth as any sort of mitigation of our massive CO2 emissions. The reasons are very clear, and one of them is indicated in the very article you linked to: (i) There is a straightforward limit to the extent to which enhanced CO2 results in enhanced CO2 sequestration, as a result of many factors (e.g. nutrient and water availibility in the real world). As author of the "co2 effect on trees" article you linked to, states: "However, the scientists who conducted the study said such high growth rates probably will not be sustained as the experiment continues. They emphasized that the results do not indicate that more lush plant growth would soak up much of the extra CO2 entering the atmosphere from fossil fuel burning." (ii) In fact rather that the terrestrial environment, by far the main "sink" for atmospheric CO2 sequestration is the oceans. However, these are increasingly less efficient in absorbing enhanced atmospheric CO2 as CO2 levels rise, first because the ocean surface tends to saturate as atmospheric CO2 concentrations rise (Le Chatalier's principle), and secondly because, as the oceans warm, they become less effective sinks for CO2 (since warm water absorbs less dissolved CO2 than cold water). (iii) Third. because as the world warms, CO2 sequestration by the terrestrial environment actually tends to decrease. This has been shown, for example, in a paper published last week in Nature: "Prolonged suppression of ecosystem carbon dioxide uptake after an anomalously warm year" John A. Arnone et al (2008) Nature 455, 383-386. Abstract: "Terrestrial ecosystems control carbon dioxide fluxes to and from the atmosphere1, 2 through photosynthesis and respiration, a balance between net primary productivity and heterotrophic respiration, that determines whether an ecosystem is sequestering carbon or releasing it to the atmosphere. Global1, 3, 4, 5 and site-specific6 data sets have demonstrated that climate and climate variability influence biogeochemical processes that determine net ecosystem carbon dioxide exchange (NEE) at multiple timescales. Experimental data necessary to quantify impacts of a single climate variable, such as temperature anomalies, on NEE and carbon sequestration of ecosystems at interannual timescales have been lacking. This derives from an inability of field studies to avoid the confounding effects of natural intra-annual and interannual variability in temperature and precipitation. Here we present results from a four-year study using replicate 12,000-kg intact tallgrass prairie monoliths located in four 184-m3 enclosed lysimeters7. We exposed 6 of 12 monoliths to an anomalously warm year in the second year of the study8 and continuously quantified rates of ecosystem processes, including NEE. We find that warming decreases NEE in both the extreme year and the following year by inducing drought that suppresses net primary productivity in the extreme year and by stimulating heterotrophic respiration of soil biota in the subsequent year. Our data indicate that two years are required for NEE in the previously warmed experimental ecosystems to recover to levels measured in the control ecosystems. This time lag caused net ecosystem carbon sequestration in previously warmed ecosystems to be decreased threefold over the study period, compared with control ecosystems. Our findings suggest that more frequent anomalously warm years9, a possible consequence of increasing anthropogenic carbon dioxide levels10, may lead to a sustained decrease in carbon dioxide uptake by terrestrial ecosystems." (iv) And of course we can cast aside "wishful thinking" notions of enhanced plant sequestration as a mitigation of our massive greenhouse gas emissions, by the simple expedient of observing the atmospheric CO2 concentratrions. If these were being reduced by plant sequestration, one might expect greenhouse gas levels to be tailing off or decreasing. In fact they're INCREASING at a rather rapid rate (faster than linear, much in line with our emissions).
131104. chris at 07:04 AM on 21 September 2008
        Arctic sea ice melt - natural or man-made?
        I forgot to post the url for the Ramanathan article in press in PNAS (see post #249) It's: http://www.pnas.org/content/early/2008/09/16/0803838105.abstract
131105. chris at 06:32 AM on 21 September 2008
        Arctic sea ice melt - natural or man-made?
        One of the possible contributions to Actic warming was raised by leebert (posts # 29,34,37,42,47,49,58). This is so-called "black carbon" (part of the man-made aerosol load from burning "dirty fuels"), of which leebert referred to work by Ramanathan who has published extensively on this subject. The human-induced aerosol load from human emissions results in a combination of cooling and warming [black carbon on ice reduces albedo and promotes melting of ice; aerosols in the atmosphere screen the solar irradiation ("global dimming"] which counters greenhouse-gas-induced warming. In fact Ramanathan has shown that the overall effect of man-made aerosols is to counter the effects of global warming resulting from man-made enhancement of the Earth's greenhouse effect (see my posts # 33,39,41,45,48,53,66). Ramanathan has just published a detailed account of the committed effect of our greenhouse gas emissions, once the "cooling" effect of atmospheric aerosols is gradually overcome. It's not an encouraging scenario. It's pertinent that the very author that leebert has used to downplay the role of greenhouse gas emissions on global warming and Arctic sea ice attenuation, is actually one of the most vociferous scientists publishing on the extreme dangeroers of the committed warming that will result from our already-released greenhouse gas emissions. here's the abstract of the paper about to be published in the Proceedings of the National Academy of Sciences: On avoiding dangerous anthropogenic interference with the climate system: Formidable challenges ahead V. Ramanathan and Y. Feng Abstract "The observed increase in the concentration of greenhouse gases (GHGs) since the preindustrial era has most likely committed the world to a warming of 2.4°C (1.4°C to 4.3°C) above the preindustrial surface temperatures. The committed warming is inferred from the most recent Intergovernmental Panel on Climate Change (IPCC) estimates of the greenhouse forcing and climate sensitivity. The estimated warming of 2.4°C is the equilibrium warming above preindustrial temperatures that the world will observe even if GHG concentrations are held fixed at their 2005 concentration levels but without any other anthropogenic forcing such as the cooling effect of aerosols. The range of 1.4°C to 4.3°C in the committed warming overlaps and surpasses the currently perceived threshold range of 1°C to 3°C for dangerous anthropogenic interference with many of the climate-tipping elements such as the summer arctic sea ice, Himalayan–Tibetan glaciers, and the Greenland Ice Sheet. IPCC models suggest that ≈25% (0.6°C) of the committed warming has been realized as of now. About 90% or more of the rest of the committed warming of 1.6°C will unfold during the 21st century, determined by the rate of the unmasking of the aerosol cooling effect by air pollution abatement laws and by the rate of release of the GHGs-forcing stored in the oceans. The accompanying sea-level rise can continue for more than several centuries. Lastly, even the most aggressive CO2 mitigation steps as envisioned now can only limit further additions to the committed warming, but not reduce the already committed GHGs warming of 2.4°C."
131106. Patrick 027 at 04:16 AM on 21 September 2008
        Volcanoes emit more CO2 than humans
        "No more than the normal "wobble" "..."For supporting evidence for actions of oscillations you can check the threads on this site. "..."it's the vulcanism driving the drift" I think we're talking about 3 or 4 distinct phenomena now. By normal wobble, do you mean Milankovitch cycles or the Chandler wobble or...? 1. Milankovitch cycles: ~100,000 yr eccentricity; ~40,000 yr (obliquity) and ~20,000 yr (precession) cycles that involve changing orientation of the Earth's axis. However, the importance to climate being the change in the axial tilt relative to the orbit around the sun; the body of the Earth itself stays aligned with it's axis the same way - the geographic north pole is still in the Arctic ocean the whole time, etc. Causes of the Milankovitch cycles: gravitational effects of other planets, solar and lunar tidal torques on the Earth's equatorial bulge (The precession cycle, a wobble of the direction of the Earth's tilt relative to it's orbit about the sun, is actually due to a combination of changing direction of tilt and a changing orientation of the semimajor axis of the Earth's orbit). (The equatorial bulge is due to the centrifugal force of rotation - the geopotential surfaces of the Earth, such as sea level, are distorted in such a way that the gravity due to mass and centrifugal force from rotation, as vectors, add to produce an effective gravitational vector locally perpendicular to the surface so that there is no local 'sideways gravity'. PS equilibrium tidal bulges can also be computed by setting 'sideways gravity' to zero. Tidal dissipation of the Earth's rotation and transfer of angular momentum to the moon's orbit result in changes in lunar tidal forces and the Earth's equatorial bulge over time (many millions of years), both affecting the obliquity and precession cycles.) 2. Chandler Wobble and True Polar Wander. As vector quantities, a spinning object has a rotation w which is parallel to the axis of rotation, and an angular momentum L. L is parallel to w if the object is symmetrical about the spin axis - specifically if the spin axis is aligned with a principle axis. (Angular momentum is equal to the rotation times the moment of inertia; but the full moment of inertial is actually a tensor quantity (written as a 3 by 3 matrix) - but if the coordinate axes are chosen to align with the principle axes of the body, 6 of the 9 components are reduced to zero, leaving three moments of inertia, each about a principle axis, so that the component of rotion along each such axis can be multiplied by the corresponding component of moment of inertia to get the component of angular momentum along that axis.) So if the rotation w is aligned with a principle axis, the angular momentum L is also aligned with w and the same principle axis. If there are no external torques applied and the body is not being deformed, there is no wobble. If the three moments of inertia are equal (such as for a perfect homogeneous sphere or a sphere with only spherically-symmetric density variations centered on the center of the sphere), L and w are always parallel. But when the body has different moments of inertia (such as due to an equatorial bulge), then L and w can be in different directions. Without external torques, L must be constant in an inertial reference frame (that does not rotate with the body); but w may shift around; in the reference frame of the body itself, I think both can shift around - the changes over time are described by the Euler Equations. In what can be called the "Tennis Racket Theorem", if w is shifted from a principle axis by a small amount, then: A. if L and w are near one of the 'extreme' principle axes - with the larges or smallest of the three moments of inertia, then L and w oscillate about that axis (specifically I think L traces out a circle about the principle axis though I'm not sure offhand), and so rotation about such an axis is stable. B. But if L and w are initially near the intermediate principle axis, L and w move away from that axis and so rotation about that axis is unstable. The Chandler wobble is a shift of Earth's rotation axis about the principle axis of the Earth most nearly parallel to the rotation axis (this is an extreme principle axis - it has the largest moment of inertia due to the equatorial bulge - the other two principle axes are in (or almost in) the equatorial plane). The spin of the Earth is perturbed by small amounts from the principle axis by earthquakes and seasonal mass distributions, but rotation about this axis is stable. (And over time, some kind of viscous dissipation would actually tend to return the rotation axis to alignment with the principle axis - for fixed L in an inertial reference fram, such alignment minimizes the square of |w| and thus minimizes the rotational energy; on Earth, the spin axis is never found more than ~ 10 meters** (much less than climatologically insignificant) from the principle axis at the Earth's surface, and the period of the Chandler wobble is ~ 440 days** - this specific info is found on p. 261 of Classical Mechanics: A Modern Perspective. Second Edition. Vernon Barger and Martin Olsson. 1995. **Caution - most info is fairly correct but I have found a few specific numbers in that book which were wildly off - the mass of Venus on p.396, and I think the rate of tidal damping and the rate of lunar orbital change by tidal damping were also off.) 3. The two moments of inertia about the principle axes in or near the equatorial plane are about equal. However, if a supercontinent persisted in mid-to-high latitudes for a time and heat built up in the mantle beneath (continental crust is of course thicker but also has more radiactive heating per unit volume than oceanic crust, both of which have more than the mantle) so that the supercontinent were elevated, conceivably if this were extreme enough (I'm not sure how far this would have to go or how likely it is it could ever get that far, especially in the distant past when the equatorial bulge would have been larger), the principle axes could be shifted out of alignment from the spin axis enough and maybe the principle axis nearest the spin axis would become an intermediate axis (? or maybe that part's not necessary) and then the rotation becomes unstable ?? - or maybe it doesn't become unstable ?? - but the end result is that the supercontinent ends up at low latitudes so once again the principle axis with the largest moment of inertia is close to the spin axis. This process shifts the whole body of the Earth around; this is true polar wander. PS if this ever happenned - conceivably it might happen (that's the impression I have as of yet) faster than it takes for the equatorial bulge to deform back to equilibrium, which means parts of the equatorial bulge could be shifted into higher latitudes - the ocean would of course respond much faster, so parts of the mid-to-high latitudes could have 'land' made of exposed oceanic crust (which could result in much release of CH4 from hydrates/clathrates) while parts of the equatorial ocean would be extremely deep. But it depends on how fast or slow the different processes occur relative to each other. The only hypothesized instances of true polar wander on Earth that I know of would be in the late Neoproterozoic, and I don't know what the state of the evidence is for it. 4. And of course over time there is continental drift as the plates grow at rifts or ridges and go back into the mantle at subduction zones. Faster plate movements should tend to correspond to greater geothermal heat transport to the surface, wider mid-ocean ridges and thus higher sea levels (although I read something recently...), and faster geologic CO2 emission. At first glance (could be wrong?) it would also make sense to expect faster mountain building and thus an enhanced erosion rate (with some time lag) - which itself would at least partly counteract the tendency for a warmer climate to sustain an equilibrium elevated CO2 level by causing faster geologic sequestration of CO2 to balance the faster CO2 release. At first glance it also would make sense to expect more frequent eruptions of all or many kinds, including those explosive low-latitude eruptions that have a short-term cooling effect - but collectively over time this would have a persistent cooling effect, but CO2 builds up over time and eventually would have the larger effect on long-term climate. The size of the plates would also have an effect - smaller plates would require a longer total length of plate margins, which could correspond in part to a longer length of mid-ocean ridges, etc. Globally the average geothermal heat loss is ~ 0.1 W/m2; even if it could have been doubled ~ 100 million years ago or whenever, that would still only be ~ 0.2 W/m2. It's a small climatological forcing and it doesn't change very fast; in contrast, doubling CO2 is a forcing of about ~4 W/m2; a 1% increase in solar TSI would be a forcing of about 3 W/m2. Have to take a break now...
131107. Quietman at 00:57 AM on 20 September 2008
        Arctic sea ice melt - natural or man-made?
        Philippe I have to agree there. Last year was quite unusual and without the freak weather and would likely not have melted as much as this year. It does remain to be seen.
131108. Quietman at 00:46 AM on 20 September 2008
        Volcanoes emit more CO2 than humans
        PS It isn't the speed of drift that is important, it's the vulcanism driving the drift which indicates a change in thermal energy released to the oceans.
131109. Quietman at 00:43 AM on 20 September 2008
        Volcanoes emit more CO2 than humans
        Patrick Re: "I don't think it would be fast enough to affect day-to-day life for most people if it happenned now" No more than the normal "wobble" that has been the norm for human existance on this planet, Ice Age 4 included. We almost went extinct once already. For supporting evidence for actions of oscillations you can check the threads on this site. John has written a few good posts on them. The origin is another matter as it is still a hypothesis (just like AGW) but somewhat harder to find papers for on the web (not a popular subject like AGW). The hypothesis has just as much merit as the AGW hypothesis however. If I can relocate the original papers I will post links to them here.
131110. Philippe Chantreau at 18:00 PM on 19 September 2008
        Arctic sea ice melt - natural or man-made?
        I don'tknow what predictions you are referring to, you're still not linking anything. The real experts were actually quite close to the mark. After all that thread on ice, you still can't look up NSIDC. You'll find all you need to know there. BTW, the answer is, they don't really know. It shows indications that the minimum has happened but only time will tell for sure.
131111. Mizimi at 06:22 AM on 19 September 2008
        What does CO2 lagging temperature mean?
        "Science does the best work possible with the best data that is available. Data are constantly sought, improved and correlated. Science is always a work in progress." I absolutely agree. And part of the process of improvement is to be open to valid critisism ( in the proper sense)and honest where data is sketchy or non-existent. Unfortunately for the scientists involved in this particular model, (I believe)it was high-jacked for other purposes and hence the current polarisation. Consequently resource which could be usefully addressing those 'iffy' areas are squandered on sawing sawdust.
131112. Wondering Aloud at 06:18 AM on 19 September 2008
        Arctic sea ice melt - natural or man-made?
        Yes check for yourself... not just at that one spot. For tree ring proxies used in the famed hockey stick and elsewhere cherry picked might be too kind. Many of them may not even be good proxies for temperature at all. An average of selected doubtful proxies does not make for a reliable record. If you can find how they chose which proxies to use and which to exclude, and why, you will find interesting reading. We have digressed a long way. How about all of those predictions of the Arctic ice disappearing this summer? How well did they make out now that the minimum is past? Remember how the young ice from last winter was going to melt much easier and all that stuff?
131113. Mizimi at 06:02 AM on 19 September 2008
        Satellites show no warming in the troposphere
        Have just graphed CO2 and GMT records from 1978 to 2007. By using the year on year change in CO2 plotted against GMT yearly change you get a remarkable match... I then factored the CO2 to get the 1998 peaks to align and then ALMOST ALL the peaks/troughs from 1978 onwards line up. Unfortunately can't find a way to put the graph on here! But you can always do it yourself ( unless someone tells me how to post it)
131114. Mizimi at 01:32 AM on 19 September 2008
        Satellites show no warming in the troposphere
        Looking at a graph generated from the Global data column it appears to trundle along with more or less equal + and - shifts until 1998 when there is a large rise of around +0.5C which declines to zero (2000) From then on there is a further large rise peaking in 2005 at +0.3C and then falling back to +0.1C From 1998 on the graph seems to include two events which have pushed the GMT well above mean. The CO2 record shows a ggod correlation to GMT fluctuations AND a spike in 1998 and subsequent spikes at the 'right' places...but the scale effect is wrong. 1998 shows +0.5C when the CO2 rise was 1.0ppm (97-98) Later CO2 increases of the same magnitude are not matched by similar Temp rises. It seems some other factors are at work..??
131115. Quietman at 23:49 PM on 18 September 2008
        Arctic sea ice melt - natural or man-made?
        Philippe Thanks for the PNAS link, that is an interesting paper. But please note the last statement just above their conclusion.
131116. Mizimi at 23:30 PM on 18 September 2008
        It warmed before 1940 when CO2 was low
        One point to consider: oil and gas as fuels did not come into widespread use until the mid 1950's and began to supplant coal from 1960 onwards. Coal was the major fuel before 1940 and emission controls virtually non-existant, so there would also have been a cooling effect from aerosols to (partially) balance GG emissions.
131117. Philippe Chantreau at 15:09 PM on 18 September 2008
        Arctic sea ice melt - natural or man-made?
        A few cherry picked proxies? That's your description. For those who'd rather check for themselves, the latest reconstruction is here: http://www.pnas.org/content/early/2008/09/02/0805721105.full.pdf+html All data, methods, and computer code are also available online.
131118. Patrick 027 at 10:11 AM on 18 September 2008
        Volcanoes emit more CO2 than humans
        "I think within a human lifetime as it would explain the rapid changes of the past but obviously this needs to be studied further." A number of sudden sharp changes can happen within seconds but they are limited in magnitude and spaced in time. Mantle convection and continental drift/plate movements are measured in cm or in per year - that's not to say there isn't variance, but the conditions driving and shaping mantle convection cannot change rapidly, and it's not going to get up to tens of meters per year (except if you go back in time far enough when the mantle's viscosity was suffiently low due to higher temperatures... that's probably closer to the beginning of the Earth than to now.) More rapid vertical movements can occur on smaller spatial scales, I think, but again, there are limits. (I expect the larger horizontal scale vertical motions caused by variations in the underlying mantle to be more gentle.) The fastest continental drift that could happen would correspond not with mantle convection but with 'true polar wander', which has to do with moments of inertia - the asymmetry of the Earth about it's axis caused by a supercontinent elevated by a buildup of heat in the mantle beneath it, for example - whether or not this ever did become a large factor in geographic changes, I'm not sure - it has been hypothesized to have occured late in the Neoproterozoic. The rate at which this could occur for a given mass distribution can be calculated fairly well - it's just a question of what mass distribution is more or less likely. I don't think it would be fast enough to affect day-to-day life for most people if it happenned now, though I haven't read so much... "It drives the ocean currents and in turn the air currents, ie. ENSO, PDO, AMO, etc. are driven indirectly by tectonics, hence the climate itself." I still don't see a good reason to suspect that or evidence to support it, though.
131119. Quietman at 08:27 AM on 18 September 2008
        Temp record is unreliable
        theTree Yes it does have an effect, producing a false feedback through CO2 release which is a GHG. The argument on CO2 is climate sensitivity. Hansen claims a high sensitivity while Spencer claims a low one. The results thus far indicate Spencer is scientifically but not politically correct.
131120. Quietman at 08:21 AM on 18 September 2008
        Svensmark and Friis-Christensen rebut Lockwood's solar paper
        Mizimi Nothing should be tossed, just put into perspective, the same goes for CO2.
131121. Quietman at 08:14 AM on 18 September 2008
        Volcanoes emit more CO2 than humans
        Re: "direct geothermal heat supply still generally wouldn't significantly affect climate, especially global climate, during most of Earth's history except near the beginning." It drives the ocean currents and in turn the air currents, ie. ENSO, PDO, AMO, etc. are driven indirectly by tectonics, hence the climate itself.
131122. Quietman at 08:10 AM on 18 September 2008
        Volcanoes emit more CO2 than humans
        PS One important factor when considering tectonic movement is that it is not entirely in the horizontal plane but also in the vertical. Portions rise while others fall and this can affect movement measured horizontally as well.
131123. Quietman at 08:05 AM on 18 September 2008
        Arctic sea ice melt - natural or man-made?
        WA I agree, botanic references in the historic records alone implicate a much warmer climate *in the locations where they were written) at that time. It proves that parts of the earth currently cold were warmer then but it does not prove it was a global phenomena. It was likely a situation more like today where we see climate shifts. I don't know what astronomy says but I am interested in knowing if it was truely a global phenomena (the current is not global as can be proven by looking at local climate histories that have remained stable).
131124. Wondering Aloud at 06:48 AM on 18 September 2008
        Arctic sea ice melt - natural or man-made?
        Well I don't know I have seen a lot of things from astronomy papers to medieval records that strongly support a warmer middle ages. Cherry picked proxy studies showing otherwise do not convince. I have no idea about Soon or various others and I don't much like OISM. However for scientific method you might want to be careful. Robinson is best known as a whistle blower on scientific method. Linus Pauling made similar charges against him and rather famously lost the ensuing law suit along with the money for his Nobel prize.
131125. Quietman at 06:41 AM on 18 September 2008
        The link between hurricanes and global warming
        Philippe Re: "all the RC contributers" No, just one, but it made me loose all respect for the site. There are plenty of other sites with pro-AGW authors that I can and do respect (like this one).
131126. Quietman at 06:29 AM on 18 September 2008
        It's the sun
        PS In other words Camp & Tung demonstrate that the recent additional warming is not from TSI, with which I can agree.
131127. Quietman at 06:24 AM on 18 September 2008
        Solar cycles cause global warming
        Camp & Tung assume the IPCC's accepted sensitivity is accurate. If we take their numbers and lower the sensitivity to Spencer's numbers we get a very different result. Their study is on the solar forcing, the feedback is assumed.
131128. Quietman at 06:11 AM on 18 September 2008
        It's the sun
        Pep John's thread on Solar Cycles is also relavent to this thread. Naturally when I used this in the Arctic Sea Ice Melt thread I was attacked by alarmists who apparently did not read it.
131129. Quietman at 04:03 AM on 18 September 2008
        Volcanoes emit more CO2 than humans
        Patrick That is the subject of my studies of late and the reason for my interest in the work done by Fairbridge. There are many point in earth's history where there were abupt changes. How abrupt these events were is totally unknown but assumed to take time because we thought that planetary evolution was both constant and steady. We now find that abrupt changes can happen very quickly. I think within a human lifetime as it would explain the rapid changes of the past but obviously this needs to be studied further.
131130. Mizimi at 02:15 AM on 18 September 2008
        Human CO2 is a tiny % of CO2 emissions
        Another point on the schematic: It is estimated 90%+ of the earth's CO2 is locked up in ocean sediment http://earthobservatory.nasa.gov/Library/Phytoplankton/ and that process is STILL going on....so how can there be any kind of a balance as the graphic indicates? The only way you can 'force' equilibrium like that is totally ignore other factors which simply destroys the basis of the argument.
131131. Mizimi at 02:07 AM on 18 September 2008
        Water vapor is the most powerful greenhouse gas
        Water vapour is present in the upper troposphere; thus it radiates heat outwards and has a cooling effect, particularly in higher latitudes where insolation is lower than the tropics. As HS. says, increased cloud cover increases albedo, and since evaporation rate is a function of water/air temperature and turbulence, warming accelerates cloud production ... Increasing cloud (eventually) increases snowfall. All negative feedbacks.
131132. Mizimi at 01:17 AM on 18 September 2008
        It's Urban Heat Island effect
        Isn't the comparison a bit off? The night-time shot is presumably a single pass compilation whereas the other is a year's data processed and averaged. I would therefore expect the UHI signal to get buried. Can't seem to find a temp anomaly picture at low enough time resolution to make a valid comparison.
131133. Mizimi at 00:23 AM on 18 September 2008
        It's not bad
        From the Ministry of Ag, Ontario: "The benefits of carbon dioxide supplementation on plant growth and production within the greenhouse environment have been well understood for many years... For the majority of greenhouse crops, net photosynthesis increases as CO2 levels increase from 340–1,000 ppm (parts per million). Most crops show that for any given level of photosynthetically active radiation (PAR), increasing the CO2 level to 1,000 ppm will increase the photosynthesis by about 50% over ambient CO2 levels. For some crops the economics may not warrant supplementing to 1,000 ppm CO2 at low light levels. For others such as tulips, and Easter lilies, no response has been observed." http://www.omafra.gov.on.ca/english/crops/facts/00-077.htm Commercial growers all over the world have invested millions of $ into CO2 enhancement of greenhouses: Given that they are businessmen, if there was no appreciable crop increase they wouldn't be doing it- No? Now I would call a 50% increase in crop mass substantial, maybe not BUMPER, but clearly enough to warrant the cash investment. So there is plenty of empirical, current, evidence that raising levels of CO2 causes plants to grow bigger and faster. It isn't an issue, it's a fact. Just as clear is that concentrations up to 1000ppm the Rubisco Activase limit does not manifest.
131134. Philippe Chantreau at 16:08 PM on 17 September 2008
        Arctic sea ice melt - natural or man-made?
        I do not appreciate the condescending implication of "starters." I have some clues about all this. You bringing Beck in the discussion does not really indicate that you know better than I. However, I notice that you now are using better sources. So now we can talk. Jaworowski has his opinion and the link you give is just that, his opinion. He has consistently declined to bet against IPCC predictions, so I don't know how much confidence he has in his own opinion. Nevertheless, that piece is not peer-reviewed science. The book is quite interesting. It emphasizes the fact that the ICE-EDGE is the really important area for production, since open water becomes very quickly nutrient depleted. Production of phytoplankton is good but eutrophization hardly qualifies as a boom for marine life. It is really anyone's guess how that ecosystem will fare if the Arctic becomes totally open in the summer. However, the book seems to suggest that the longer the water is open and the larger the open area, the quicker it will be nutrient depleted. I noted another return on your search query page indicating a lack of success at netting krill, why is that? http://www.imr.no/arctic/cruise_diary/phytoplankton_bloom_on_spitzbergen_bank The AGU paper is about a computer model to simulate blooms and does not really go beyond that, at least as far as the abstract says. Am I to assume that you trust computer models for complex systems involving biological and physical components? The Siberian forest paleo data is interesting but what exactly is your point there? Does it really suggest a much different total latitudinal repartition ot just different boundaries? How exactly is it applicable today, when humans have so much influence on ecosystems? The bristlecone vertical growth paper says this: "Average density above tree line is greater than below tree line, though no statistical significance can be shown." If I had the classic, obnoxious skeptical attitude, I'd say that you really can't draw any conclusion from this because of the lack of statistical significance. I won't go as far, but say that it remains to be shown that this is more of an extension in vertical repartition than simply a upshift. As for your other links on growth rates (and your summary dismissal of the Rubisco activase problem on the other thread), it considers trees in isolation of ecosystems. There is no doubt that biomass can store carbon, everybody knows that. The problem is that we won't let it happen. Let me put it on other words: how likely is it that the enhanced growth rates, will compensate for the land use changes? How about more frequent wildfires? How about parasites and invasive species? You made the argument that complexity restricts our comprehension about climate, but complexity is even more of a restricing factor with forecastin the behavior of ecosystems. You have no problem betting on it, that's your take. The tree paper also says this: "However, the scientists who conducted the study said such high growth rates probably will not be sustained as the experiment continues. They emphasized that the results do not indicate that more lush plant growth would soak up much of the extra CO2 entering the atmosphere from fossil fuel burning."
131135. Philippe Chantreau at 14:18 PM on 17 September 2008
        What does CO2 lagging temperature mean?
        Your post #14 is accurate but you could have traded "somewhat" for "less than 1%." Science does the best work possible with the best data that is available. Data are constantly sought, improved and correlated. Science is always a work in progress. If you want to talk about a really inexact science, we should start with economics.
131136. Patrick 027 at 09:43 AM on 17 September 2008
        Volcanoes emit more CO2 than humans
        " Sometimes no action, sometimes slow and sometimes quickly. One was on "continental drift" (tectonic activity) rate changes and another on mountain building at subduction zones. So yes, geologically speaking these things can happen quickly," but how quickly is quickly?
131137. Dan Pangburn at 09:14 AM on 17 September 2008
        Water vapor is the most powerful greenhouse gas
        A study of satellite data on clouds and water vapor indicates that prior predictions of substantial Global Warming are wrong. The study introduces a new method to diagnose the total radiative feedback parameter. Corrected analysis will result in low climate sensitivity where the GCMs predict insignificant global warming with increased atmospheric carbon dioxide. The subject is discussed at http://www.weatherquestions.com/Roy-Spencer-on-global-warming.htm . A completely independent analysis reveals that there is insignificant net positive feedback. This has the same effect on the climate as the finding of low climate sensitivity. Examination of the temperature data of the last and prior glaciations from NOAA as determined from Vostok ice cores reveals that temperature trends reversed direction irrespective of carbon dioxide level. This proves that there is no significant net positive feedback. Climatologists, who apparently don't know how feedback works don't realize this. Unaware of their ignorance, they impose net positive feedback in their GCMs which causes them to predict substantial warming from carbon dioxide increase. Without significant net positive feedback, the GCMs do not predict significant Global Warming. An assessment from a third perspective also determines that there is no significant net positive feedback. It can be seen at http://www.climate-skeptic.com/2008/01/index.html
131138. Philippe Chantreau at 03:47 AM on 17 September 2008
        The link between hurricanes and global warming
        Healthy skeptic, you really think I'm pulling this out of my rear-end? Denigrating scientists and accusing them of intellectual dishonesty, fraud, etc is so common among skeptics, it seems to be all they have. Even the moderate Quietman has no problem about accusing all the RC contributors of being biased and suggests that their funding is a cause of their "views" despite the fact that they do not receive funding from anyone to keep up the site. I've never heard you protest because he was denigrating these scientists. Do you even know what some of Gray's claims are? Have you checked the existing research about his claims? Find me the published papers that Gray would, according to you, be alluding to in the WSJ story, then we talk again. Gray is a respected expert on hurricane forecasting. He has published many papers on that subject and tropical meteorology. His track record of publications on climate science is quite different. But, as I said, if you have papers that would be of interest, link them. That what this site is all about. However, save us the memo circulated for the 2006 conference on hurricane and tropical meteorology, it is not a peer-reviewed science paper. Gray still calls on deep water upwelling from the tropics into the THC in this piece, an idea that has been discredited for a long time. He also seems to believe that evaporation can somehow make energy disappear. He makes all sorts of claims on historical behavior of the THC that do not have supporting evidence. Nobody is infaillible. Interesting is the fact that Gray testified in Congress that the Termo Haline Circulation was accelerating (while there was no real oceanographic evidence of it), leading to increased hurricane activity, then changed his theory when evidence was published that the THC was actually slowing down. As glider says, scientists don't know everything about hurricanes, which are really more a feature of weather than of climate.
131139. Mizimi at 00:33 AM on 17 September 2008
        Arctic sea ice melt - natural or man-made?
        Phillipe: try these as starters:- ice core records siple curve pre ind co2 www.john-daly.com/zjiceco2.htm http://books.google.co.uk/... http://www.agu.org/pubs/crossref/2006/2005JC002994.shtml http://www.google.co.uk/search?hl=en&rlz=1G1GGLQ_ENUK279&q=arctic+phytoplankton+bloom&meta= Whilst it is off topic you might like to read these on treeline movement and CO2 response which show that the biosphere is responding with negative feedback. http://www.sciencedirect.com/... http://216.239.59.104/... co2 effect on trees growth rate sour oranges
131140. HealthySkeptic at 15:10 PM on 16 September 2008
        The link between hurricanes and global warming
        #11 Philippe >> "Another what on what list? Not on the list of real science papers, or otherwise scientific references that Mizimi is pointing to. So far you got us Beck, who manages to fumble with his own made up BS, and a WSJ article. Impressive. Last I look, WSJ was not about science.... Gray is one train late (and some of his ideas about climate defy the laws of physics, but that's another story). " And a damn fine story too, I'll bet. LOL! Are you seriously suggesting that Prof. William Gray's more than 40 years of tropical meteorological research experience is not "real science", as you call it. This attitude of denegrating well respected scientists who don't agree with your world view is reminiscent of Creationist tactics! It is certainly not a scientific approach.
131141. Quietman at 14:49 PM on 16 September 2008
        Volcanoes emit more CO2 than humans
        Patrick Unfortunately the ENSO hypothesis I had put in my notes but I did not write down the source. At the time I was looking to find out what drives El Nino for my own knowledge so it was not important to me to note the source. I remember it was a dot-gov site and I searched for "el nino". Re: Not happening quickly. There is an article at ScienceDaily.com (or LiveScience.com) that explains why we need to rethink rates of change for the earth. It seems that the earth works in spurts. Sometimes no action, sometimes slow and sometimes quickly. One was on "continental drift" (tectonic activity) rate changes and another on mountain building at subduction zones. So yes, geologically speaking these things can happen quickly, we just don't take notice of the changes unless we happen to be monitoring them (and we have not been for very long).
131142. HealthySkeptic at 14:39 PM on 16 September 2008
        Arctic sea ice melt - natural or man-made?
        # 222 cce >> "The climate change over the past few million years has zero, zilch, nada, nothing to do with any change between the '30s and today. They are completely different mechanisms." What evidence do you have for that? cce>> "Every metric tells us that it is warmer now than in the '30s. You reject this conclusion, based on numerous independent observations, in favor someone's crackpot theory about plate tectonics." A large number of skeptics believe that the GW is happening. What they have trouble swallowing is that it is happening as a result of human activities. cce>> "(3) The IPCC accurately summarizes the state of the peer reviewed science, which is why the relevent scientific societies (who are responsible for actually producing the science) endorse the IPCC findings. Yes, they do at the moment. But recently, more and more scientists are changing their minds (as good scientists should) and rejecting AGW when the data and observations don't agree with the hypothesis. And AGW is just that at the moment, an hypothesis.
131143. Quietman at 14:20 PM on 16 September 2008
        Arctic sea ice melt - natural or man-made?
        Philippe Distain is a little strong. I use the wiki sites for a quick reference but I don't take them seriously and double check what I read. I see too much inconsistancy and errors in subjects that I am very familiar with. As I said before, Palaeos is two sitesL Palaeos.com and Palaeos.org, the dot-org site is a wiki and while better than wikipedia is still questionable and needs to be verified. Kind of like peer-reviewed papers (more than an article but less than established documents). The references posted at both, however, are reliable means of cross-checking. A wiki that slams people (or any site that does this) I simply don't go to. I come to this site with an open mind and to learn more about Climate Change. But as a skeptic I question both extremes and take neither as fact. It has helped my understanding quite a bit. I just don't care to argue with someone that has a closed mind as you have seen. I do not address anyone once I have seen the trend in their arguments. I have done some editing on Wikipedia but essentially spelling and grammar. When I disagree I go to the discussion page to point out the errors and let the original author do the edits (and there are many errors).
131144. Patrick 027 at 14:12 PM on 16 September 2008
        Volcanoes emit more CO2 than humans
        Quietman - I went back and looked - it appears I did skip over the link from your comment 8. When I click on there now, though, it takes me to a list of other science (and politics about science) blogs (which sidetracked me because they were interesting). Aside from that, nowhere did I see in any of the links you supplied here a claim of some recent change in geologic activity - the closest being speculation that changes could be occuring related to an ice stream in Greenland (doesn't apply to all of Greenland) and the Pine Island glacier (doesn't apply to all of West Antarctic ice sheet) - neither of which are affirmed as being due to a recent change in geological forcing - so it is still quite possible that any recent changes there could be due to changing climate, with some such locations perhaps being more sensitive or having different thresholds because of a constant geological factor. I interpreted other articles (such as those concerning explosive submarine eruptions or the mid ocean ridge in the Arctic) as being new discoveries - not indicating a change in the actual thing that had been discovered. (If there is some quote to contradict that which I missed please point it out to me). "The current hypothesis on the cause of ENSO is not the volcanic eruptions, that is symptomatic not cause, the cause is undersea volcanic vents along the subduction zone as explained in the tectonics article." I missed any such connection made between submarine volcanic activity and ENSO behavior - could you provide the quote from the article? (I'm not saying that geothermal heating itself wouldn't have some effect, but I think (those calculations I did at "Science and Society") that except in some rare extreme cases, the temporal variation on such short timescales would be miniscule compared to so many other available variations that might trigger or modulate ENSO behavior. I don't think compositional fluctuations from hydrothermal vents would have big enough effect (such as on buoyancy, on a large-enough spatial scale) to be significant in ENSO either. ..."not all volcanos produce them"... [aerosols] ..."or outgas the same compounds." Agreed. "SO2 outgassing hss a different effect than CO2." Agreed. "Particulates from undersea eruptions do not reach the atmosphere." Agreed. "SO2 and CO2 released by these submerged volcanos have two dramatic effects: convection currents and acidification of the ocean (something blamed on AGW but actually volcanic in origin)." Well, no I disagree strongly there. First, it isn't AGW itself, technically, but the emission of CO2 that is a major cause of AGW, that is directly causing ocean acidification as well (not that climate itself can't affect (bio)geochemistry, but in this case I don't think that's a big factor). Second, the amount of CO2 geologically outgassed is miniscule compared to anthropogenic emissions, and more importantly, it didn't change a lot just recently (on a timescale to matter to AGW, or even to glacial/interglacial variations). The long term SO2 emission rate probably isn't changing much either. Of course there are short-term variations, like single eruptions, but overall these are relatively constant fluxes, and so biogeochemical conditions will long since have responded to them until fluxes balance, so there is a steady state on intermediate time scales. "Recent tectonic activity has been observed under antarctica recorded as earthquakes along the transantarctic mountains (an ancient fault line or plate edge)." Now, that's interesting. But even if it were unusual in the last 100 or 200 years, is it unusual in the last few thousand years? "The thinning of the crust under Greenland is directly related to it's active volcanos, mountain growth and seafloor spreading or rifting." But that's not the kind of thing that happens quickly. My overall point being that there isn't evidence of changes in geological activity over such a time period such that they would be causing a significant part of the climate change over the last decades or even centuries (except for explosive volcanism into that air that produces aerosol cooling, which is accounted for by climate theory and models), and also, there isn't really a reason to suspect it as a significant factor. But of course a relatively constant geological condition, such as a hotspot under a part of greenland, could have an effect on the response to climate change, such as the response of overlying ice to warming at the ice surface and above.
131145. glider at 11:12 AM on 16 September 2008
        The link between hurricanes and global warming
        It is interesting the reduction in OHC is just brushed off as "short term cooling". There is a reason why since 2003 the oceans have stopped gaining heat. It cannot be ignored since it is at the core of the AGW argument. See Hansen et al 'Earth's Energy Imbalance: Confirmation and Implications'. Amazing. Ten years of OHC rise and it becomes the "smoking gun" for AGW. Five years of cooling and it is "short term" insignificance. Where is the missing heat? Isn't the real truth about hurricanes as is the case in other aspects of climate that "scientists" really don't know as much as they portend? Cloud dynamics, convection, solar and others are not well understood either. http://www.agu.org/pubs/crossref/2008/2008GL033950.shtml This paper is still in press (need subscription to view abstract), so will link to this blog: http://climaterealist.blogspot.com/2008/09/new-paper-us-hurricane-counts-are.html Now, what makes anyone think that small changes in solar activity does not also affect earth's climate as a whole?
        Response: Several years of ocean cooling is not unusual over the last 50 years of ocean warming. Solar activity certainly does have an effect on earth's climate - it's believed the 11 year solar cycle has an impact on global temperature of around 0.1C. So it wouldn't be surprising if this had an impact on hurricane intensity which is increasingly being linked to sea surface temperatures. More on the link between sun and climate...
131146. Philippe Chantreau at 05:48 AM on 16 September 2008
        Arctic sea ice melt - natural or man-made?
        Mizimi, people who deny the reality of evolution and want to have creationism taught as if it was science are irrational and superstitious. Allowing them to alter school curricula will be detrimental to education. I have not yet personally met a Christian scientist who believed that ID or creationism should be called a scientific alternative to Evolution. You seem to go on a tagent and essentially make a strawman, but I won't discuss it. What evidence do you have that sea ice melting will be beneficial to the cycles that you so vaguely and loosely describe? Studies? Links? If you are so intent on respecting the complexity of climate, how can you suscribe to the simplistic and fabricated nonsense that Beck spreads around? There is an enormous amount of real scientific litterature out there on every aspect of climate (even hypothetical ones) and on the all shebang as well. Your disdain for wiki is rather strange, Quietman. I recently noticed they have a lot of links to Palaeos.
131147. Quietman at 04:03 AM on 16 September 2008
        It's the ocean
        Looking at the maps you will note that the warming occurs along ridge lines. This is NOT coincidental, nor is it caused by AGW but quite the opposite. Refer to comment 13 in the volcano thread linked above.
131148. Quietman at 03:55 AM on 16 September 2008
        Volcanoes emit more CO2 than humans
        Patrick From "Could Volcanic Activity In West Antarctic Rift Destabilize Ice Sheet?" (the first one you found): "However, this study also shows that the land in West Antarctica has been rising beneath the ice sheet in some areas and subsiding beneath it in others, over roughly the past 25 million years. Some areas have subsided to as much as 8500 feet below sea level. This tectonic restlessness contrasts markedly with the stability of the regions that lay beneath the northern hemisphere ice sheets of the recent geologic past, and its affect on the history of the West Antarctic ice sheet has not yet been evaluated." This relates again to the tectonics article linked to in my comment (13).
131149. Quietman at 03:46 AM on 16 September 2008
        Volcanoes emit more CO2 than humans
        Patrick Yes, I linked to Neds blog because you make an interesting argument in the Bertha thread. I thought that John and some of the other posters here would also find it so. On the arctic volcanos, these were new massive undersea eruptions in 1999-2001 along the arctic ridge, this relates to NEW increased seafloor spreading. The 2007 article on tectonics supports this and the subsequent additional heat convection currents concept. The current hypothesis on the cause of ENSO is not the volcanic eruptions, that is symptomatic not cause, the cause is undersea volcanic vents along the subduction zone as explained in the tectonics article. The aerosol issue is not involved in my argument because not all volcanos produce them or outgas the same compounds. SO2 outgassing hss a different effect than CO2. Particulates from undersea eruptions do not reach the atmosphere. SO2 and CO2 released by these submerged volcanos have two dramatic effects: convection currents and acidification of the ocean (something blamed on AGW but actually volcanic in origin). Recent tectonic activity has been observed under antarctica recorded as earthquakes along the transantarctic mountains (an ancient fault line or plate edge). The thinning of the crust under Greenland is directly related to it's active volcanos, mountain growth and seafloor spreading or rifting. These are like puzzle pieces, each one is not very significant in itself. but added together, along with what little we understand about gravitational stresses, begins to make some sense of what occurs in very long climate cycles.
131150. Quietman at 03:11 AM on 16 September 2008
        It's the sun
        Mizimi Thank you, I was not aware of that.

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