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A climate change paradox (part II)

Part I was posted in The antidote to 150 million quadrillion joules.This is the updated and revised calculation.

Michael Hammer previously calculated that if the IPCC were right, the oceans should have absorbed a lot more heat, but just how much? He has revised his previous calculation after discovering an error. Now instead of oceans missing as much as 90% of the heat capacity, they are missing less, but it’s still around two-thirds. Its a lot of energy that somehow, somewhere, is not being absorbed. Where is the energy that greenhouse gases are supposedly ‘trapping’? Not in the air, and not in the water. What sort of radiative imbalance is this? Not one to get scared of.

Naturally, as always, Michael is keen for people to check his numbers and give us feedback.

Here is another example of a skilled expert doing pro bono work because he is concerned at the state of the science and the unnecessary damage to our society that it will bring. Michael Hammer has around 20 patents in the field of spectroscopy, that means he’s produced work that’s so useful and original that his employers have shelled out hundreds of thousands of dollars to get those ideas checked, assessed and recorded. That doesn’t mean he’s right, but it means he’s worth listening too, and it’s another powerful example of the grassroots movement at work.

The Bumper Sticker Message still stays the same: One of the new bluffs is rising ocean temperatures, or increasing oceanic heat capacity. The big number 15 x 1022 Joules looks frightening but translates to just 0.15 °C over 40 years. That’s an immeasurable 0.003 °C per year.

JoNova

Again, cross posted with Jennifer Marohasy.

A Climate Change Paradox (revised)

Guest posting by Michael Hammer
Australia’s Minister for Climate Change, Penny Wong, recently suggested that most of the global warming since 1960, about 85 percent, has happened in the oceans and that change in ocean heat content is thus the most appropriate measure of global warming.

In my previous post, working from first principles, I determined a discrepancy of 9:1 in the rate of warming from Australian government data relative to IPCC findings. In reviewing these calculations I now realise I made a significant error. I had wrongly assumed that the claimed positive feedback from water vapour was proportional to the carbon dioxide concentration. This is not correct, the claimed positive feedback is proportional to the temperature rise and that change does make a difference to the calculations and needs to be corrected. The revised calculations still show a paradox although only about 3:1.
I had calculated the heating sensitivity of Earth (kappa) by differentiating Stefan’s law for a temperature of 255K and this came out as 0.266°C/watt/m2. That figure is very much in keeping with the findings of others for example Soden and Held (2006) 0.25°C/w/m2 , Hansen et al (1984) 0.26°C/w/m2 , Bony et al (2006) 0.263°C/w/m2 , Colman (2003) 0.30°C/w/m2 , Kiehl (1992) 0.305°C/w/m2 . For a 3°C rise, kappa predicts the additional retained heat is 3/0.266 = 11.3 watts/m2 for doubling of carbon dioxide. A significant fraction of this 11.3 watts/m2 comes from the claimed positive feedback effect of rising water vapour. My error occurred in calculating a current retained heat of 11.3 × 0.45 = 5.1 watts/m2 in 2006 (0.45 doublings of carbon dioxide) because we have not seen the full equilibrium rise in temperature (otherwise there would be no net energy flow into the oceans) therefore we will not be experiencing all the claimed positive feedback from water vapour. That means my figure of 5.1 watts/m2 is too high.
I repeat the calculations more accurately below.
If the feedback is proportional to the temperature, (water vapour increases exponentially with temperature but its effect is logarithmic therefore the effect will be the logarithm of an exponential which is linear) then it is indeed valid to allow for the positive feedback by adjusting the heating sensitivity of Earth rather than calculating the positive feedback explicitly in watts/m2. In short, instead of using kappa (the sensitivity without feedbacks) use lambda the sensitivity with feedbacks factored in. This is the approach adopted by many other scientists.
Popular reporting suggests a temperature rise between now and 2070 of 3°C. In fact checking back to the IPCC 4th assessment report what is actually claimed is that a doubling of carbon dioxide leads to an increase of 3°C which is somewhat different to popular reports. Doubling carbon dioxide leads to a direct increase in retained energy of about 3.7 watts/m2 which would mean a value for lambda of 0.81 (3/3.7).

So how much heating has occurred? The temperature of the planet has been going up and down all the time. By selecting an appropriate reference year one can claim almost any warming one desires. However several sources all claim that AGW only started around the end of the second world war and temperature changes prior to that time were of natural origin. For example from Wikipedia; “The Intergovernmental Panel on Climate Change concludes that increasing greenhouse gas concentrations resulting from human activity such as fossil fuel burning and deforestation are responsible for most of the observed temperature increase since the middle of the 20th century. The IPCC also concludes that natural phenomena such as solar variation and volcanoes produced most of the warming from pre-industrial times to 1950 and had a small cooling effect afterwards. These basic conclusions have been endorsed by more than 45 scientific societies and academies of science”.
http://www.grida.no/publications/other/ipcc%5Ftar/?src=/CLIMATE/IPCC_TAR/wg1/005.htm shows 0.4°C warming since about 1950 although I shows the temperature at that time changing by 0.2°C in 5 years so the exact point chosen makes a large difference.


http://www.pnas.org/content/103/39/14288/F1.large.jpg shows between 0.4
°C and 0.5C

http://data.giss.nasa.gov/gistemp/2005/ shows about 0.4°C since 1945
I also note that the government paper specifically talks about ocean heating since 1960 further reinforcing this point. In fact their data shows no ocean heating prior to 1975.
Using a temperature rise of 0.4°C, and a value of lambda of 0.81 the extra energy radiated away from earth accounts for between 0.4/0.81 = 0.49 watts/m2 . But IPCC claim that the direct effect of the rise in carbon dioxide in 2006 (the report was released in Feb 2007) was an increase in carbon dioxide forcing of 1.66 watts/m2 and a total impact from all direct factors (ie: excluding feedbacks) of 1.6 watts/m2 . This means that 1.6 – 0.49 watts/m2 or 1.11 watts/m2 of the total forcing must have gone into heating the Earth. But the retained energy calculated from the government paper was 0.32 watts/m2 into the oceans (representing 85% of the total) for a planetary total of 0.32/0.85 = 0.38 watts/m2. 1.11 versus 0.38 is still a discrepancy of 3 times although smaller than my previous claim of 9 times.

Carrying out the calculation the other way round, if 0.38 watts/m2 is being retained, then 1.6-0.38 = 1.22 watts/m2 must be being radiated. If that was happening with an 0.4
°C rise lambda would have to be 0.4/1.22 = 0.328 °C/watt/m2 . A figure of lambda = 0.328 and kappa = 0.266 still suggests a small amount of positive feedback (lambda is greater than kappa) but far less than that claimed by AGW supporters. A sensitivity of 0.328 would suggest an equilibrium temperature rise for doubling of carbon dioxide of 3.7 × 0.328 = 1.2°C. However in 2070 carbon dioxide will still be rising and the planet will still be warming, we will not be at equilibrium. We could reasonably expect the same level of energy to be flowing into heating the earth as at present (about 0.38 watts/m2). In that case the actual rise for doubling carbon dioxide would be (3.7 – 0.38)× 0.328 = 1.09°C. Since we are currently seeing 0.4°C, that would mean a further rise between now and 2070 of 0.69°C which is a far cry from the popularly reported 3°C.
All this of course assumes that the starting data is correct. In fact there are reports that the oceans have been cooling now for some years and that the steep rise shown since 1998 is an artifact arising from the change to the Argo buoys. These two factors would reduce the 0.32 watts/m2 figure significantly. Also, there is significant dispute over the justification for the corrections applied to the raw temperature data which result in the claimed 0.4°C rise. The satellite data from UAH shows far less warming. If these concerns have substance, then the impact of rising carbon dioxide is even smaller suggesting that the net feedback is in fact negative not positive and the temperature rise between now and 2070 would be less and possibly substantially less than 0.69°C.

I apologize to readers for my error in the previous article and hope this sets the record straight.

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Rating: 6.1/10 (7 votes cast)
A climate change paradox (part II), 6.1 out of 10 based on 7 ratings

Tiny Url for this post: http://tinyurl.com/2e9nq7e

53 comments to A climate change paradox (part II)

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    BobC

    Since the “missing” heat hasn’t been going into the oceans lately (according to the Argos float data), it is likely that it has simply been reflected back into space. The measurements of Earth’s albedo (reflectiveness) support this hypothesis, see: http://wattsupwiththat.com/2007/10/17/earths-albedo-tells-a-interesting-story/

    If this is true, then the “missing” heat is lost and not sitting around somewhere waiting to restart global warming whenever the (unknown and unmodeled) natural variations allow.


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    Robin

    I think that the ocean has been taking the missing heat, lately, and that the data referenced in the link is out of date.

    See oceanic warming: http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/

    And: Correcting Ocean Cooling, a discussion of locating the errors in the ARGO and XBT data.

    Certainly it hasn’t been reflected into space, because the energy imbalance at the top of the atmosphere is measured. (See: Earth’s Energy Imbalance: Confirmation and Implications)


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    BobC

    Robin:

    The best measure of ocean heat content change we currently have is the ARGO float data. In the first link, the ARGOS data is pasted onto earlier estimates without an attempt at calibration, resulting in a discontinuity at 2003. This seems somewhat sloppy, but is apparently tolerated for the nice graph it produces of increasing ocean heat.

    In the NASA site you link, http://earthobservatory.nasa.gov/Features/OceanCooling/page1.php , Josh Willis describes how he “adjusted” the ARGOS data to make it fit his expectations by removing probes that were “too cold” and averaging in XBT data known to have a warm bias. Even after all this, he still had a slight cooling. There has been no attempt that I have been able to find to recover some of the probes Willis rejected to actually measure their calibration for a reality check.

    While Willis’ behavior was apparently not controversial with his colleagues, it generated criticism from those with knowledge of good scientific practice. He has since modified his description of what he did (see: http://climaterealists.com/index.php?id=2079 ) to conform with accepted practice. This “explanation” contradicts his original report in some key respects.

    The paper by Hansen you link to basically ignores the actual ARGOS data and claims, using models, that the heat is indeed being stored in the oceans.

    I would suggest that a number (Earth’s energy imbalance) derived from the difference between two large numbers — one of which is largely derived from models and the other from difficult measurements — is likely to be mostly noise. Much more informative are the measurements of Earth’s reflectivity by fairly direct means (the albedo data).

    The albedo data clearly shows that the Solar forcing has been changing over decadal time scales by multiple times the amount of forcing corresponding to a doubling of CO2. This is not good for the AGW hypothesis and so will probably be ignored.


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    Plonk

    So, as I understand it – if the data is unexpected adjust it!
    If the results had shown too much heat would the data have been adjusted then? I think not!


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    [...] A Climate Change Paradox (Part II) | JoNova [...]


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  • #
    co2isnotevil

    Plonk,

    Look at my last posting in Goldilocks to see how a similar deception is present in the satellite data.

    George


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    co2isnotevil

    Robin,

    As we discussed earlier, your methodology for calculating the heat capacity of the oceans is flawed, as is your assumption that the flux in and out is small. The satellite evidence is unambiguous that the oceans respond to changes in the incident energy far faster than the decades required for AGW. For the same reason a thin layer of the crust stores heat on the land, only a thin layer of the ocean stores heat. The evidence of this is the ocean temperature profile and the fast response of the oceans to changes in energy.

    The objection you raised to this earlier was that you didn’t believe that the ocean surface temperature was indicative to the energy stored in the ocean. It is as long as there is sufficient vertical mixing in the top, thin, layer involved with storing heat, which of course there is.
    The evidence of this is the relatively constant temperature of the ocean between the surface and the top of the thermocline, delineating the thin layer involved with storing heat.

    George


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    Tel

    Is there a good reason for constant recalibration of the sea probes? You can buy for around $20 from the chemist a digital thermometer to stick under your tongue that is accurate to three sig-figs (or one part in a thousand). These devices remain stable for years with no maintenance and quite arbitrary handling.

    If you want to spend a bit more money, a real thermocouple with a high quality digital multimeter should also achieve one part in a thousand accuracy over a much wider temperature range. Hook whatever digital datalogger you want on the back of that.

    In my mind, the best way to detect a long term trend is to calibrate it once and then leave the field probe alone without twiddling with it. One identical probe can stay back in the lab in controlled environment as a proof unit so that the long term stability can be identified. Measuring temperature is off-the-shelf technology these days.


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  • #

    Tel,

    Measuring temperature over long time periods isn’t quite as easy as you think. There are serious long term stability problems which are affected by temperature and pressure cycling.

    Thermocouples aren’t real temperature measurement devices. They only measure the difference between the hot and cold end of the wires.

    Your chemist digital thermometer is *precise* to thousandths of a degree but may be accurate only to one degree or more likely around 0.1 deg or so.

    Platinum resistance is better and should have well known characteristics.

    There should be a bunch of Argo probes in the lab being temperature and pressure cycled as the operational ones are along with some being kept in a nice stable environment with periodic checking. I saw a post the other day where someone said he was unable to find any evidence that the alleged bad Argo probes had been recovered and checked.


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    Tel

    Measuring temperature over long time periods isn’t quite as easy as you think. There are serious long term stability problems which are affected by temperature and pressure cycling.

    Well in the old days they just had mercury in a glass tube and all of our historic land-based records are based on some guy coming round once a day to peer at the glass tube and write it in the book. That was probably accurate to 0.1 degree and the mercury doesn’t change much, nor does the glass. There’s enough day to day variation that only after lots of readings over a very long time can you measure a trend. In which case accurate to 0.1 degree should be perfectly good, just requires long term stability more than anything else. I mean, we have automated weather stations right round the world, presumably someone believes that they are giving reliable data.

    I’ve got a cheap multimeter that uses a thermocouple to measure the temperature of a room (and the meter is in the same room), seems to have some internal electronic reference, dunno how they do it but lots of devices have this ability so it can’t be so very difficult.

    Then there are a range of single-chip pyrometers available which should be OK to observe the infra-red emission of the seawater.

    Even put a bunch of different devices and collect measurements from all of them, how much extra would it cost to put one of each? I mean the cost is all in the deployment and data collection, not in the sensors.

    This is yet another case where I’d very much like to see the basic raw data before it has been touched by anyone, rather than see what comes out after “correction” and other munging. After the hockey stick, I’m less inclined to trust anyone who includes black-box steps in their scientific process. If there’s genuine broken sensors or a probe gets eaten by a whale then fair enough, but the whole recalibration business seems very suspicious. Doesn’t quite ring true with other temperature sensors that operate autonomously for years.


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  • #

    Mercury in glass has lots of problems as I’m sure you can find out if you do a search.

    I was once a guy who came around once a day to peer at the glass tube and write it in a book when I was base meteorologist at RAAF Pearce 1972 to 1975.

    The automatic weather stations were largely not intended to collect long term climate data. The accuracy to one deg C or so is plenty good enough to predict the imminent likelihood of fog or whether you need to wear a jumper today or if the runway will be long enough for your aircraft under current conditions. Getting meaningful long term climate data is another problem.

    You cheap multimeter/thermocouple does have an internal electronic reference. It is called cold junction compensation and likely is a semiconductor temperature sensor. The whole setup is as accurate as the semiconductor sensor. No more. Easy to get to a degree or so of accuracy. More difficult for much more than that. I’ve lost count of how many of these I’ve built.

    Getting reliable long term temperature data requires a lot of care in sensor selection and periodic checks on calibration against a standard. At least that’s the way science used to be done. I’m not sure the climate folks are that good anymore.

    Incidently this issue also applies to radiosondes. Few are recovered so the calibration of most is open at one end. I have a scheme to fix this.


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    BobC

    Mike,
    Incidently this issue also applies to radiosondes. Few are recovered so the calibration of most is open at one end. I have a scheme to fix this.

    I’m dying to know what your scheme is (if it is non-proprietary, that is).

    Perhaps a really little on-board triple-point cell? (Might not take much energy if the outside temp was below 0C — just wait until it was half-frozen, then take its temperature.)


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    Nope. It is a method to enhance recovery rate of radiosondes in an expeditious manner. The ones that get recovered now may have been sitting in a field for months.


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    BobC

    Mike:

    I guess GPS technology is so cheap now that you could use that to radio a position after the radiosonde lands.

    My brother worked at NCAR during the ’60s building radio links for their very large high altitude balloon flights. Typically, the instrument packages were cut loose from the balloon and parachuted down while being observed by chase planes. To keep the parachute from dragging and destroying the package, there was an additional explosive cutter to cut it loose after landing. One flight, the wires got mixed up and the package was cut loose from the balloon — and the parachute — at 120,000 ft. They had a little trouble finding that one on the Texas plain as it was at the bottom of a narrow 8 ft deep hole!


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  • #

    No Bob, it is better than that. One of these days I’ll run some tests.
    The better radiosondes have GPS on board nowadays. Means you get real time winds without radar.


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    Seems the way to “do” climate science is accept the data if it matches your theory. If it doesn’t match, “correct” it. If that doesn’t work, reject it as faulty data. If that is the “correct” way to do climate science, then why bother with the measurements? Simply write down the numbers you want to see and report that as “the data”. That way, your theory will always be “supported” by the data and should be good for another two year extension of your research grant.

    Wait! That IS what they are doing. Never mind. We must trust the simulations…we must trust the simulations…we mus36 90qae odncm,a–89uo phjhf,,,,,,,#####,,,,


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    Mike MacCracken

    Dear Michael—The discrepancy you are finding is the result of a fundamental flaw in your approach—basically a misunderstanding of how the greenhouse effect works. Perhaps the simplest way to illustrate this is to consider Venus and Earth as analogous to two different states of the Earth’s climate (we can do this on a per square meter basis using planetary averages). Venus is closer to the Sun, but has a higher albedo than the Earth, so absorbs less solar radiation per square meter than the Earth. It is presumably at equilibrium and so its emitted long-wave radiation would equal its incoming solar radiation. As just a rough estimate, assume it is emitting the same amount of radiation as the Earth to space, so it would be radiating long-wave radiation equivalent to a blackbody at a temperature of 255 K. It has no ocean, but a thick greenhouse gas atmosphere. Its surface temperature is observed to be roughly 750K—so its natural greenhouse gas effect is almost 500 K. Pretty impressive.
    If we take the Earth in its preindustrial state, again at equilibrium, its radiating temperature to space, based on an albedo of about 30%, is 255 K. And its average surface temperature was roughly 288 K, so a 33 K natural greenhouse. The radiation of energy to space, at equilibrium, balances the incoming solar, and it really says nothing about what the surface temperature is—that is determined by a planet’s atmospheric greenhouse effect.
    So, now we start adding greenhouse gases. If there were no heat capacity and so an instant response, there would be a new equilibration of surface temperature and the radiating temperature to space stays the same. This can happen because the average height at which energy is radiated to space goes to a higher level because the atmosphere above the initial average height of radiation is now optically thicker in the long-wave.
    When the system does have a heat capacity, what happens (i.e., assuming no change in cloudiness or surface albedo, and a few other thing) when one adds greenhouse gases is that the incoming solar energy absorbed stays the same, but the outward long-wave to space drops a bit because the average height of radiation to space becomes higher (and so colder, assuming here everything is convectively coupled) and this lasts until the planet warms up enough so that higher layer is warm enough to radiate away to space the same amount of energy absorbed. So, until the planet gets to equilibrium, there is a small net gain of energy to the planet due to the reduction in loss of infrared energy. This imbalance will stay about the same over time because just as the outgoing long-wave goes down as the greenhouse gas concentrations go up over time, the world is warming and so pushing the temperature and hence the outgoing emissions over time.
    The time constant for the adjustment is of order decades due to the ocean (and longer due to deep ocean, glacial ice, etc.) so what should be happening at the top of the atmosphere is a slight energy imbalance. Now, limitations in the accuracy of instruments and global coverage in space and time of day introduce uncertainties, so it is hard to measure, but my understanding (from studies like ERBE—Earth Radiation Balance of Energy) is that the imbalance is of the order a few to several tenths of a W per square meter—and this is just about the same as you are finding as the average rate of heat storage in the ocean and atmosphere. So, the observed heat content in the ocean and atmosphere is the integral over time of a relatively small flux difference.
    The changes in radiative fluxes at the surface will be considerably larger than this—as surface temperature goes up a degree, one gets the kind of change in flux that you calculated. But that is not what is happening for the planet as a whole—as the Venus analog indicates, one can have a much higher surface temperature at the surface without affecting the net outgoing long-wave radiation at all.
    Just one more thing—in doing this, of course, one has to consider al forcings—so all gases and aerosols, changes in surface albedo, solar and volcanic effects, etc. (so solar input and absorbed can change—and one has to account for system adjusting to that as well). Obviously, the real system will be responding to all forcings—one should not, of course, expect global average temperature to be responding just to CO2, as was calculated in some early climate model simulations, though the same reasoning would apply to the estimation of changes in fluxes at the top of the atmosphere.
    So, while you were right to think about the full warming not being realized, your approach to estimating what the accumulated energy should be was not correct (and I would have thought your science advisers would have caught this).

    Michael MacCracken, Ph.D.
    Climate Institute
    Washington DC


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  • #
    co2isnotevil

    Michael,

    One more thing about Venus. When a 15u photon is absorbed by a CO2 molecule, it’s effective temperature increases (based on the kinetic energy gain) by 100′s of degrees C. In the Earth’s atmosphere, this energy is readily shared with the other, colder, molecules in the atmosphere via collisions, and it’s the sharing of this energy which quantifies the greenhouse effect. In the Venusian atmosphere, the energized CO2 can only share it’s energy with other energized CO2 molecules and the result is that the atmosphere stores a significant amount of energy as super heated CO2. In other words, what we know of as the greenhouse effect is only valid at low concentrations of greenhouse gases. Once these gases start to comprise the bulk of the systems heat capacity, a completely different kind of process takes over.

    Add to this the 100% cloud coverage and this why Venus is so hot. While clouds reflect solar energy, the warming from the retention of surface energy is a bigger effect. Venus is not so much a case of runaway greenhouse effect, but of a runaway cloud coverage effect. Clouds modulate the release of energy from Earth, but lack the dynamic range to do this on Venus. The only possibility for a similar effect on Earth would be if all of the water in the oceans evaporate, which would actually happen if we were as close to the Sun as Venus is or if the Sun got considerably hotter, but could never occur under any circumstances as the result of incremental GHG’s. If you could magically heat the Earth to the temperature of Venus, all of it’s water will evaporate and the Earth would look a lot like Venus. The one difference is that at the current Earth orbit, the climate would eventually revert back to it’s normal behavior.

    Another thing that people consistently get wrong is that GHG retained energy is not new energy being added to the system, but old energy being retained by the system. Many of the models which predict nonsense like runaway warming treat GHG energy as if it were new energy coming from the Sun. You can only treat GHG energy as new energy if you subtract it from the surface first!

    George


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    Mike MacCracken

    I don’t sense any disagreement here with my concern about Michael’s incorrect analysis of energy content. I agree for example that it is retained energy that is being processed by the greenhouse process. The only caveat I would make is about clouds (or any of the greenhouse gases): they will only be able to exert a warming influence if energy (generally the visible energy) makes it to below the greenhouse gases or clouds. As was clearly shown in “nuclear winter” calculations and can be shown theoretically, is that if, for example, all incoming solar energy is absorbed above the greenhouse gases, then radiative processes will make it isothermal below that level and there will be no greenhouse effect. So, on Venus, the clouds actually limit how much solar makes it below them, and below the greenhouse gases, so even to the extent they absorb upcoming long-wave energy, their reflection of a lot of solar energy does indeed limit the warming of Venus–make Venus darker, and it would be even hotter for, as a whole, it would have to emit more energy.


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  • #

    Mike McCracken,

    So the oceans warm according to the energy imbalance at the top of the atmosphere not the energy imbalance at the surface interface?

    So what happened to the ocean warming since 2003?

    George,

    Lets talk about Mars. 95% Co2 atmosphere, no significant clouds or water, half the energy arriving at top of atmosphere, nearly same axial tilt. Damned cold.


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  • #

    George,

    I should have added, nearly same length of day also


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    co2isnotevil

    On Mars, the CO2 is only a small fraction of the total heat capacity, while on Venus, the CO2 represents almost 100% of the planets heat capacity. This is the difference. If Mars had 40 atmospheres of CO2 and something to condense into clouds, it would be uncomfortably hot and show no seasonal or diurnal differences either.

    George


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    Mike MacCracken

    TAs to the recent apparent lack of oceanic warming, trends over several year periods are very noisy, especially given the limited coverage of ocean observations and the variability created by the ENSO and other oscillations (that is why climate is officially a 30-year average). Based on what we know, those variations keep going on (and we are apparently headed into an El Nino). In addition, for the ocean, there have been a number of adjustments going on in the record due to new insights into the sink rate of the expendable bathothermographs (XBTs), changing mix of observations types as there are offsets between instrument types for various reasons, and so on (e.g., see https://www-pls.llnl.gov/?url=science_and_technology-earth_sciences-ocean_temperatures). Plus only the heat above a depth of something like 700 m is monitored–not to greater depths. And, in any case, one has to be very careful to allow the different approaches into looking at such things time to be done so one really gets to a rigorous and peer-reviewed set of findings. I don’t disagree that the apparent lack of warming is an interesting question to be looking at, but we need to be careful not to jump to conclusions.


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  • #
    BobC

    Mike MacCraken,

    I looked at the link you gave. They apparently believe that climate models produce DATA:

    “Climate models provide spatially complete ocean temperature data, so unlike the incomplete observations, infilling is not required.”

    So much more convenient than messy field work — just sit at your computer and produce ocean temperature data.

    What a surprise that this “data” produced by the models, agrees with the models. Since it’s so much more “complete”, we shouldn’t worry that it doesn’t agree with the measurements.

    These scientists need to look up the definition of “circular reasoning”. (One of the best is in Donald Knuth’s “Art of Computer Programming”. In the index under “Circular Reasoning” it says “see Reasoning, Circular” — under “Reasoning, Circular”, it says “see Circular Reasoning”.)


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    Mike MacCracken

    That’s about as good a vague arm wave as I’ve seen lately.

    I think what you mean is: “Despite the real world measurements(that are probably the best there are, ever), that show lack of ocean warming recently, we can cast doubt on these because they don’t agree with our models and are incomplete and besides there are older measurements of unknown accuracy which these better measurements don’t agree with.”

    Ya think there might be something wrong with your models?

    My wife just read your post of 7:55 and laughed. She’s not a trained scientist but knows bs when she sees it.


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    Mike MacCracken

    If you want to get a sense of the potential for problems relying on short trends in the data, check out David R. Easterling and Michael F. Wehner, 2009: Is the climate warming or cooling? GEOPHYSICAL RESEARCH LETTERS, VOL. 36, L08706, doi:10.1029/2009GL037810.

    And if you believe that data are automatically right, remember how many adjustments have been required to get the satellite data record and radiosonde records right–and those instruments have been around for decades. In the oceans there are as many potential problmes in the data set.

    A colleague of mine once wrote a paper entitled: “Which should you believe: observations or models?” His answer was observations. My answer was neither-we have to be skeptical of both, and also learn from both–based on how good they are. Just believing in one or the other is not appropriate for scientists–test and then retest, etc. May sound funny, but that is the way scientists are.


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    Mike MacCracken:
    August 6th, 2009 at 7:55 am

    “I don’t disagree that the apparent lack of warming is an interesting question to be looking at, but we need to be careful not to jump to conclusions.”

    It is really only terribly interesting if you *expected* continued warming. Otherwise it is unremarkable. You are the one jumping to conclusions and as for avoiding jumping to conclusions, that is what those of us who oppose precipitate action to reduce CO2 emissions are doing, given the lack of evidence that it is doing much at all and counter evidence that says a little more CO2 is probably a very good thing.


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    Mike MacCracken

    With the CO2 concentration going up (and I do presume you agree with that time history), very straightforward physics makes clear this will create a warming influence–and for a very long time due to what is very clear about how slow the ultimate sink processes are. They physics of all this explains the different conditions on Venus, Earth and Mars, and lots more–so yes, there is a presumption of warming (and there are no other factors than the greenhouse gases that would operate in this way). That Earth history makes clear that the climate can change–and interestingly seems a bit more sensitive to changes in forcings such as the greenhouse gases than the models calculate due to some slow-acting positive feedbacks. I would be very interested to hear how you can explain the variations in climate over Earth history assuming a very low climate sensitivity to the amount of energy that is trapped by the greenhouse gases.

    And the climate is changing–just go to the Arctic and high latitudes. Indeed, I don’t have a film of the increasing CO2 warming the climate, but there is a very clear fingerprint of actions by greenhouse gases being the predominant cause. And it is not, as the report on this Web site claims, due to a lack of scientists looking for influence of natural factors such as solar variations and volcanic eruptions–that has been going on for far longer than studies of greenhouse gases. And we do find a solar influence–the changes in the orbit of the Earth about the Sun make clear how important the amount of solar radiation is in affecting the climate. So, all these claims that we are not looking at natural factors is just nonsense–but the evidence of it being the predominant factor in recent changes is just not there.

    And sea level rise is occurring, at a rate faster than we can explain by just thermal expansion, melting of mountain glaciers, and surface changes on ice sheets. The inadequately considered factor appears to be ice dynamics, which we have evidence is happening more rapidly than previously, but is not yet included in the needed models. With much of the West Antarctic and Greenland ice sheets grounded below sea level so that warmer ocean waters can get at and increase the loss rate, the potential for the term that the IPCC did not include in its numbers for the projected amount of sea level are now–from mainline scientists like Bob Bindschadler–being estimated at about a meter by 2100, plus or minus about 50%. How you can suggest that further CO2 emissions is thus likely to “probably be a very good thing” needs a lot more justification than such a casual comment.


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    Mike MacCracken @ 28,

    Keep that up and you are sure to get your next research grant. However, don’t rely on your models to be anything but models that assume what you are trying to prove. Circular Reasoning does not work in the real world. Its only valid in the world of fantasy and political correctness.

    Science is done by looking carefully at all the evidence not just the evidence that supports your pet theory. For every point you make, a counter point has been repeatedly made in this blog that shoots your pet theory all to hell. It only takes one counter factual to destroy it. No amount of correction, adjustment, obfuscation, or argument by authority can fix it.

    Enjoy your research grant while you can.

    Once again we have clear evidence that PhD really means “Piled Higher and Deeper.” Most of the time, credentials aren’t worth the paper they are printed on. Its real world results that count but the real world is not your focus.


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    Mike McCracken:

    I’m not aware that anyone has satisfactorily explained the all the climate variations in Earth history. I see lots of conjectures some of which might make hypothesis standard and there is historical evidence that the climate has changed in the past at rates and to extents which make the current very slight warming entirely unremarkable and certainly not possible to pin on CO2 alone.

    Nice arm wave on the “slow acting feedbacks”. Does any of your modeling do biology? After all the 20% oxygen atmosphere we have was created and is maintained by biology. This just my conjecture but I would not be surprised if climate variations were largely the result of chaotic biological processes.

    How’s the greenhouse gas physics working out on Mars which has 30 times the mass of CO2 over each square meter of surface as does Earth?

    “And the climate is changing–just go to the Arctic and high latitudes. Indeed, I don’t have a film of the increasing CO2 warming the climate, but there is a very clear fingerprint of actions by greenhouse gases being the predominant cause.”

    I’m not disputing the climate is maybe changing but there is historical evidence that the Arctic ice comes and goes on various time cycles. We haven’t actually been looking at it very well for very long. Meanwhile there’s the sea ice extent in the Antarctic to explain away as well as the lack of tropical troposphere hot spot and please don’t quote that junk science garbage from Santer et al about that. Clear fingerprint? If there was a clear fingerprint nobody would be arguing with you.

    “And we do find a solar influence–the changes in the orbit of the Earth about the Sun make clear how important the amount of solar radiation is in affecting the climate. So, all these claims that we are not looking at natural factors is just nonsense–but the evidence of it being the predominant factor in recent changes is just not there.”
    Kind of like the evidence for predominant CO2 influence wouldn’t you say? Except that maybe you’re missing what the sun really does. Svensmark seems to be strengthening his case.

    I’ll believe any of this sea level rise stuff when I see it. It seems the sea level rises and falls in different places at different time scales ranging from daily tides to thousands of years. Measuring it is extremely difficult for many reasons. Ask a harbourmaster. A geologist cousin of my wife’s asked his local council “climate change officer” in New Zealand(in a town with a large harbour) about sea level rise and got a detailed exposition of the problems that sea level rise over the next 50 years would cause. Then he asked him how much they had measured the sea level rise over the last 50 years at the local harbour and got arm waving and obfuscation. Same when he asked the person with the same job in Auckland. Obviously it is a great problem.

    Joanne should be pleased. Shehas attracted a Warming Alarmist Champion. Readers may like to Google “Climate Institute” to find out where Mike McCracken is coming from. He’s made quite a career out of pushing the climate alarmist case. This of course assumes it is the same Mike McCracken.


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    Mike MacCracken

    To Lionel (29): Why is it that every time someone objects to a Skeptic, the charge is that the person is in it for a government grant? It does your cause no good at all to switch away from the issues and make gratuitous insults–how do you expect to have legitimate discussions if your main approach is to hurl insults? For the record, I retired from my 30-plus years of government paid research activities in 2002 and am not pursuing any government grant, etc. nor have I been on a grant for the years since retirement–most things I have done are for no pay (travel costs do get reimbursed). I admit to getting some occasional honoraria and consulting (maybe a tenth of my former salary total), but not for being an alarmist.

    And for Mike Borgelt (29), yes, I do a lot of mostly volunteer work with the Climate Institute (and occasionally a bit more) and a lot of other entities. Spelling is MacCracken if you really want to do a search.

    On science issues–so you accept satellite data on tropospheric temperatures that require a radiation model to invert (indeed one that would explain the greenhouse effect) and that has had to go through a lot of adjustments over the last decade and a half, but you do not accept the satellite data on sea level height, which is a much more direct measurement). And what about the satellite data on the decreasing mass of both Greenland and Antarctic ice sheets–and note the IPCC’s central projection of their combined effect over the 21st century is about zero–not so very alarmist given that already the satellite observations suggest that their combined effect already is adding to sea level rise. And then there is both on site and satellite evidence of melting mountain glaciers–so contributing to higher sea level rise. Instead what you offer is a visit to one or two locations with no sort of analysis of other influences (like land moving up or down for natural or human-induced reasons, etc.)–would you let me get away with that? I think not.

    And greenhouse models do work on Mars–same physics, different composition, pressure, distance form the Sun, etc.–in fact a colleague in graduate school was applying the same model to Mars as I was applying to the Earth–back in the 1960s.

    It is true we have not explained (or got good observational data on) all of Earth’s past variations, and there are some we cannot explain (like the Cretaceous–a CO2 concentration of 1500+ ppm and shifted continents are not enough to explain polar warmth. So, yes, lots of things to still learn, generally indicating that the climate models we have are not sensitive enough to explain the observed changes given the forcing factors that we can reconstruct–so it would appear that there are some additional, likely long-term, feedbacks, quite possibly involving biological changes, etc.

    Regarding this blog, I came on because Michael Hammer seemed to be curious about an interesting question, but had a serious flaw in his approach. In that he had indicated a willingness to alter his analysis as he had learned more (i.e., correcting from the first version to deal with the fact that climate is not at equilibrium, so I thought he might be interested in further input–the physics can be hard to understand, so I thought I’d offer a comment. If no one else is interested in discussing the science issues, well, have fun in your own world instead of out in the world of mainstream scientific discussion of issues. I’ll go back to where I can perhaps help to improve overall understanding.


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    Mike MacCracken @ 31,

    Oh poor boy, can’t take being crossed. You respond to the insult rather than the fact your pet theory can’t hold water if you look at ALL the data and not just the cherry picked data that supports your theory. Its not science that you are doing.

    PS: Don’t let the door hit you on the way out.


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    co2isnotevil

    Mike,

    You seem to acknowledge that there’s a lot we don’t know. I would add to this list that we don’t know how 3.7 W/m^2 of incremental forcing power is converted into 3C of temperature difference, when the first principles relationship between energy and temperature (Stefan-Boltzmann) bounds the effect at about 0.6 C. The AGW hypothesis is that this amplification is the result of water vapor and maybe ice feedback, but the problem remains that water vapor feedback would act relatively quickly and we should be seeing the effect already. No monotonic trend can be discerned in the data, relative to noise and natural fluctuations. None the less, about 2C of the projected 3C warming should have already happened, which is large enough to see if it was present.

    To address the missing heat, the AGW talking points are that the oceans respond slowly to the change. Even if this was true, much of the CO2 increase happened long enough ago that any deferred effects should already being apparent. The satellite data also shows that ocean temperatures change far more rapidly in responses to changes in energy than the AGW hypothesis requires. Even the global average ocean temperature varies by several degrees C during the course of a year. This can’t be explained away simply as hot and cold water exchanging places, but as energy entering and leaving the Earth’s thermal mass. Yes, the Earth is never in static equilibrium. During half of the year energy is entering the Earth’s thermal mass and during the other half, energy is leaving. There’s no monotonic gain of energy happening because of incremental GHG, nor any deferred future effect.

    If you align the Mauna Loa CO2 data with the time varying average temperature of the planet, there are intervals where in the short term, CO2 is increasing, while the temperature is decreasing and visa versa. This would suggest an inverse relationship. However, this is just the short term effect of biology, where increasing temperatures stimulate biomass which starts to remove more CO2 from the atmosphere than natural (mostly decomposition) and anthropogenic (mostly burning fossil fuels) are returning back. Long term, biology is limited by CO2 as the temperature is rising and limited by energy as temperatures are falling. We also see this in the ice core record where the CO2 lag is longer when the temperatures are falling than when temperatures are rising. It takes a while for CO2 to drop, plus additional dead biomass contributes more CO2 as it decomposes. What the CO2 (and CH4) in the ice core record reflect is the total biomass present on the planet, where the smaller changes in the CO2 to CH4 ratio reflects the relative ratio of fauna to flora.

    If you examine the 80 W/m^2 difference between perihelion and aphelion, the global average temperature is decreasing as the Earth gets closer to the Sun and increasing as the Earth gets farther away. If you examine this carefully, it quantifies the effect that ice ages will have on the Earth’s reflectivity and energy balance. This also quantifies the ice feedback effect which is far too small, relative to a 3.7 W/m^2 increase, to boost this up to 3C, at best, it will increase it to about 1C. If you account for incremental CO2 under clouds having no effect (the clouds are already mostly opaque to long wave radiation), the upper limit for what 3.7 W/m^2 could produce is actually less than 0.5C.

    Given all the issues, do think a multi-trillion dollar experiment in climate control based on regulating atmospheric CO2 is justified? There’s far more data suggesting that CO2 is not a significant factor than the other way around and there are a lot of very smart people who are unconvinced about the claimed magnitude of the AGW effect. Most of the so called correlation surrounds the coincidental confluence of the end of the little ice age and the start of the Industrial Revolution which is no where near enough to justify this incredibly ill conceived experiment.

    George


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    I found this on seal level measurement:

    http://sealevel.colorado.edu/calibration.php

    Seems a little circular at first glance. I’ll look into it some more however it seems that sea level rise isn’t accelerating and sea level rise has been with us since the end of the last ice age. Some fraction of a meter sea level rise isn’t all that much to worry about as we seem to have coped with 0.1 to 0.25 m in the last century and hardly noticed it. My point about the New Zealand story is that all sorts of wild pronouncements are made about future rise and yet they can’t tell you what happened in the past. It’s not impressive. In any case the economic lifetime of human assets by the sea shore is likely less than 100 years so probably no special extra effort is involved in coping with projected sea level rises. If you live near the beach Tsunamis are the worry not long term sea level rise.

    George: “Most of the so called correlation surrounds the coincidental confluence of the end of the little ice age and the start of the Industrial Revolution which is no where near enough to justify this incredibly ill conceived experiment.”

    Exactly.

    Mike MacCracken(sorry about the spelling error that slipped in earlier): You are entirely too modest as perusal of this shows: http://www.climate.org/about/maccracken-bio.html. I’ll let my comment on this stand though. Numerical modeling doesn’t necessarily represent the real world. How did the asteroid impact thing work out? I’m more worried about that and money spent doing something about it has other side benefits.

    How did your colleague know the surface pressure and Martian atmosphere composition in the late 1960′s? I’ve seen estimates of greenhouse warming on Mars being 5 to 10 deg C. There’s only one gas on Mars with this effect and there’s 30 times as much as there is on Earth over each square meter. Radiative models on Mars will need allowance for convection. I doubt that this is all that simple. I’m wondering whether the warming at the Martian surface as anything to do with “greenhouse” trapping or more with the mere presence of a deep convective atmosphere.


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    co2isnotevil

    Both Mikes,

    I’ve done simulations of Mars using my model as well. Mars has less total GHG absorption as a percentage of surface energy, mostly owing to the lack of water vapor, which on Earth contributes 2/3 of the GH effect. Even though by mass, there is far more CO2 in the Martian atmosphere, the width of the 15u absorption line is about the same as that of the Earth’s atmosphere.

    Even if Mars had an atmosphere similar to the Earth’s, it would still be a relatively cold place. Similarly, if Venus had an atmosphere and oceans like ours, they wouldn’t last as Venus is close enough to the Sun that the water would boil, leading to conditions similar to what Venus is like today. Runaway GHG doesn’t explain Venus since the atmospheric window is still plenty wide enough to let out heat. It the clouds of Venus that trap far more heat than the CO2, although all of the energy absorbed by CO2 pretty much stays with the CO2, contributing to the higher than expected temperatures. The only way to accommodate the Venusian surface temperature is to recognize that a 15u photon increases the temperature of a single CO2 molecule by 100′s of degrees and that the only other gases CO2 can share this absorbed energy with are other, already energized, CO2 molecules.

    George


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    Thanks George.
    Have you tried running your Mars model with Mars shifted to Earth’s orbit? What I’m trying to understand is the effect of 30 x CO2 when there aren’t any other gases, oceans water vapour etc to obfuscate the issue.


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    co2isnotevil

    Mike,

    If Mars was in Earth orbit, it would still be very cold, The lack of water vapor is the problem. The 30x more CO2 is not a factor, as the absorption spectrum is hardly affected by higher concentrations. Even the 15u absorption band in the Venusian atmosphere, is about the same width as that of the Earth.

    The logarithmic effect on concentration is more applicable to unsaturated lines than to saturated lines. At high concentrations, the absorption spectrum appears asymptotic to a limit.

    George


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    Mike MacCracken

    On Mars (Mike 34): In the climate model calculations done on Mars by a colleague in the late 1960s, you are right to ask how he knew what to model. Indeed, he didn’t as it was before any satellite had landed. There were a number of hypotheses about what would be found by the landers, and, as I recall, he ran a number of those cases, ruling out some given the Martian climatic parameters that could be observed. And he did have the possibility of CO2 condensing into dry ice and snowing out. Quite clever.

    I should note regarding your comment in 37 that Mars also has a much lower atmospheric pressure, and without water vapor to carry heat upward to levels where it condenses, the lapse rate on Mars (i.e., decrease in temperature with height) would be quite different and not sustained at the typical rate on Earth. Indeed, if we did not have convection on Earth, the surface temperature would be higher and the decrease in height greater, so it is more than just the amount of CO2 in the atmosphere that makes for the difference.

    On the asteroid impact topic, aside from the Cretaceous extinction by a 10 km or so asteroid, I was on the organizing committee for a meeting several years ago about how important the threat of asteroids is for us today. There was an interesting range of views. There appears to be a power law relationship on sizes that are observed in space, and the count for those bigger than a kilometer is going well (with NASA investing an amount roughly equivalent to a penny a year per US citizen)–next step is to get to about 150 m diameter at cost of about a penny per month per US citizen, seeking to identify those that could strike Earth during 21st century. The Tunguska one in Siberia in 1907 (I think it was) leveled 2200 square kilometers of forests and is though to have been 30-50 m in diameter, so we are far from having inventoried all that could do a lot of damage. Interestingly, counting of craters on the land surface seem to suggest that there have been a few times more hits than the power law suggests, and anthropologists and coastal geologists seem to have indications of a still higher level. At that time, not clear what the discrepancy was and I am not up on later results. On global catastrophe that caused the extinction, not yet an agreed upon mechanism among a number of ideas. On damage from a smaller impact, calculations had only looked at direct effect possibilities (so chance of hitting a city, etc., with little thought about hitting of critical locations (like dry forests that might catch fire, etc.). On ocean impacts, some disagreement on potential for tsunami due to where the wave may break (at coast or at edge of coastal shelf). And then it became evident there was no real reporting process up to governments and that media would likely get information first if someone spotted an asteroid or comet headed toward Earth. So, overall, very interesting. The proceedings are in a book put out by Springer (see Comet/Asteroid Impacts and Human Society, P. Bobrowsky and H. Rickman (eds.), Springer, Dordrecht, The Netherlands, 546 pp.).

    On being a modeler (so as to comments of George 33 and Mike 34), do realize that models are based on physics, with additions, as necessary, based on the type of empiricism that George cites (e.g., clouds in my model were a function of relative humidity squared based on some very rough observations–not perfect, but then that was the late 1960s and it was a step up from fixed clouds). Correlations are interesting and qualitative reasoning can be useful, but models force one to be quantitative and have to consider all processes and not just focus on one’s favorite or perhaps what one thinks is the primary process. Models are really only doing all the calculations that we wish we could do so fast and with such resolution, keeping track not only of the large terms but also the small ones that are often most important when the large terms tend to cancel out. So, models force real rigor into the argument assuming they are used properly–they are not just something one uses without knowing how things are working, and one must indeed understand how and why things are working (which is why Ben Santer et al.’s efforts have been so important, contrary to someone’s earlier put down of his work). So, George, while your commentary is interesting, it really needs to be tested out in full quantitative models–and that is what the ocean-atmosphere GCMs are attempting to be (they basically incorporate what we understand about each process, and increasingly this includes biology and chemistry). And so they are run against various cases, and then seeks to understand why they agree or disagree–what are the correlations that emerge, etc. Your model is primarily a mental one, the climate models should have the processes that you think are dominant in them, plus many others, and then one sees how it works–how well each can explain the observations (and, of course, the real world is responding simultaneously to all forcings, not just CO2) and how consistently the approach can be applied to related situations. So, in my view, models need to be utilized to help and check one’s understanding and analysis–not replace it, but at the same time, one must have such models as a check, because it is easy to be misled by one’s own thinking if is is not checked in a rigorous and quantitative way.


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    Mike MacCracken

    To Mike (msg 34)–On the sea level site you suggested to me, it seems to me that what the point of the analysis was was to see if the satellite and tide gage stations were giving the same result of rise (if there was a drift, it would show altimeter problems), and in that they are not showing a drift (one instrument seems to have an offset), are these results not showing that the satellite and the set of sea level stations that were identified (and combined into a single record) are giving the same result (I assume at these locations). In any case, this seems to me to be saying that we can combine the surface tide gage record and the satellite global record, and the satellite record since 1993 shows a good bit higher rate of rise than the tide gage record for the whole 20th century. So, an increase in the rate of rise (though over different lengths of time).

    I would note also that two years ago I got to visit the 2800-year old remains of the Phoenician salt flats in southern Sicily. The site has been operating since then and up to present. Only recently are the Phoenician walkways and channels starting to be covered by rising waters (assuming the land is not sinking, etc.).


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    co2isnotevil

    Mike,

    You are underestimating my model and my capabilities. It’s far from just a thought model and has been coded up for a while now. The framework around the model has the capability to correlate results to ice core data and satellite data. If you’ve looked at my slide set,

    http://www.palisad.com/co2/slides/siframes.html

    you might notice that all of the plots were produced by the modeling framework I built to plug my model in to. I don’t talk about my model in the slides, because it’s really not necessary to illustrate my points.

    The problem with the ocean-atmosphere GCM’s is that in order to accurately predict climate, the chaotic boundary between the hot and cold pools of the earth’s stored energy must be modeled precisely (i.e. weather). This is hard to do and even the best models have a hard time projecting more than a few days ahead, let alone decades to centuries. We can’t even predict simple things like El Nino’s and only know of them by ocean surface temperature measurements. We even know one is setting up in the Pacific , but nobody has any idea how strong it will be, even as the absolute strength can make as much as a degree C difference in the average yearly temperature. How can a model which can’t model this, and needs to in order to be accurate, be trusted?

    I should also point out that something I’ve developed for my model is a way to draw a box around the chaotic bits in order to relax the requirement for accurate simulation at this boundary. I’ve also been using techniques related to formal verification (something we do with complex integrated circuit models) to validate my model as being hierarchically consistent with thermodynamics and COE.

    I’ve been involved with modeling and simulating many, many different kinds of systems, far more complex than the climate, and the single largest effort is in the area of model verification, which relative to the GCM’s is largely absent.

    Back to the point, you still haven’t answered my question about whether AGW science is solid enough to justify a multi-trillion dollar climate control experiment. I would request that you think a little deeper about how 3.7 W/m^2 is turned into 3C. You have some time to think about it as I will be off skiing glaciers in the Sierra Nevada mountains over the weekend and won’t get back to civilization until Monday.

    I would also like you think about the wisdom of the ‘science is a done deal’ argument. Based on feedback from my legislators and even Obama, this claim is what’s driving cap and trade. Your a scientist, surely you know that it only takes one contrary experiment to disprove a hypothesis and you should recognize that AGW is just a hypothesis. The only other place I’ve seen this kind of claim is from people pushing fringe physics.

    George


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    Mike MacCracken

    Dear George—Thank you for referring me to your slides, and apologies for underestimating your efforts—quite interesting, though not surprisingly, I have some questions and comments (I do wish the slides were number to more easily refer to particular ones):

    1. I agree with quite a number of your points. In particular, I agree that Earth history indicates that climate change has occurred at many time scales. I also tend to agree that the changes have causes, and the challenge is to figure out which ones do what.

    2. In your paleo section, as I understand your points, you come to the conclusion that biology is the dominant factor. But how does the biosphere make the atmospheric CO2 concentration low when the temperature is low and high when it is hot? Where does the carbon go? Do you agree that the carbon goes into the ocean when the ocean is colder and comes out when it is hotter, and the timing will depend on a number of things, like the overturning rate of the ocean, the extent of ice cover capping ocean release/preventing uptake, etc.? You do not seem to mention the role of the ocean, and it is hard to see how the ocean could not be involved, creating a thousand year or more time constant due to the slow deep ocean turnover time.

    3. You comment in one of the slides something like ‘Greenhouse gases have almost no influence on the energy budget.’ If what you mean is that the greenhouse gases and changes in their concentrations have almost no influence on the planetary energy budget, I think I understand—they don’t directly affect the albedo, so don’t affect how much solar is absorbed—and at equilibrium, as much energy has to be emitted as is absorbed, whatever the greenhouse gas concentration is. However, as the differences between the Earth, Venus, and Mars indicate, the greenhouse gas concentrations and role have a lot to do with what the surface temperature is, and indeed, were there not greenhouse gases in the atmosphere, the Earth’s surface temperature would be a lot lower, right?

    4. In you paleo discussion, you suggest that the IPCC crowd calls the CO2 a forcing regarding glacial cycling. This is not really correct—we call the CO2 effect a positive feedback. Indeed, its change is a result of changes in the ocean, biosphere, atmosphere carbon balance. For the recent time, when fossil fuel is burned, the CO2 influence on atmospheric radiation is indeed called a forcing, but it is also recognized that the CO2 feedback process will be at work as well, ultimately having an effect (and a growing number of models are therefore including the CO2 concentration as a prognostic variable, and the fossil fuel emissions as a source.

    5. Now, you call orbital influences a forcing. By the IPCC definition, this is not really the case as the orbital influences have, essentially, a net zero annual, global influence. By the IPCC definition (which I have questioned in review comments), the redistribution of energy over latitudes and seasons is not strictly considered a forcing; maybe the net albedo effect of the different geography would be, but they instead suggest that the albedo of the ice sheets during glacial periods creates an albedo forcing. In my review comments I have made the point that this is a tenable explanation only until we get more computer power, when ice sheets will properly be a long-term feedback.

    6. I was interested in your argument that it is the hemispheric difference alone that, when driven by orbital forcing, leads to the glacial cycling. My impression has been that models do not get enough of a response for this (that is, they are not sensitive enough), although I do not know enough about the details of how the orbital variations are being implemented to be really confident on this. I was asking just the other day about this issue of making sure that one deals with the changes through the year in Sun distance, etc., and I have not checked the coding of a model to really be sure that is being done. My guess is that it is, as there have been a lot of simulations of paleo-periods and I would assume that this issue would have come up and been dealt with long ago.

    7. In your slide about “Long-term auto correlation,” I did not understand the argument when you said that the was a “global temperature dip as the Earth came out of the last ice age.” Do you really mean “dip”—is this the Younger Dryas you are talking about, or what?

    8. The first part of the paleo section was devoted to this issue of the CO2 effect, with you concluding it was not there. In that we scientists and you agree that it is orbital elements that is the driving force for the changes, I don’t understand how you can do your analysis for the CO2 influence (which, as I said, we all consider during these times to be a feedback—not a forcing) without first subtracting out the orbital element effect. So, your correlations of past and future influences seems very strange, in that orbital elements are, we agree, the key driver—so why can one rule out a CO2 influence just because the response is not driven by CO2—we do not say it is? We certainly agree that CO2 is not the driver of glacial cycling—and your analysis seems to nicely rule that out, but it does not seem to me to speak at all about the presence of a CO2 feedback (that is tied to oceans and biology, with complex delays, etc.).

    9. On the discussion of the CO2 radiative effect, your comments on saturation of bands is all if you consider the atmosphere as a single isothermal layer (that is, you have radiation absorbed in the atmosphere either radiated up or down, the up to space and the down to the surface), when things are much more complex than that. In the first radiation model I worked with, what was done was to divide the atmosphere into layers of equal opacity (and while the first model was broadband, it would be better to do with various spectral intervals)—say of 0.05. These layers in the absorption band regions are then closer to having the same upward and downward radiating temperature. So, adding more CO2 makes these layers thinner, and so they radiate up and down at different temperatures—the ones radiating to the surface (that is, that the surface sees) tend to be at a lower altitude and so warmer, while the ones radiating to space tend to be higher and colder. As a result, until the surface and troposphere (which on Earth are convectively coupled in most regions) warm up so that the upper layers are warmer, the Earth won’t be radiating to space as much solar radiation as is absorbed. And with the lower atmosphere also warmer (and holding more water vapor, making the layers of equal opacity even thinner near the surface and so warmer), a lot more energy will be radiated to the surface, increasing its temperature.

    10. Now, in your Greenhouse Forcing section, you say some puzzling things. You seem to say that since this radiation is not new incoming solar radiation, it is not a forcing. Agreed, by definition, it is not forcing, but it is energy and this is what feedbacks are all about. The thinner layers mentioned above are providing real energy to the surface and this causes warming, just as would adding energy put off by a nuclear reactor. Just because it is recycled energy does not mean it cannot cause warming (that is how Venus works, for example; or it is just how money works—there are real purchases made every time it changes hands, not only the first time it is issued by the Federal Reserve). You also say that greenhouse gases basically delay energy’s release—well, what they do is keep recycling energy, constantly emitting day and night (more during the day as temperatures, and thus emissions, are higher by the Stefan-Boltzman relation).

    11. On your discussion of hemispheric differences, I was a bit surprised that the Northern Hemisphere seasonal cycle of temperature stretches over 24 K. In that you also separate out an equatorial region with a smaller variation, I was wondering what latitude range you consider as the Northern Hemisphere (and Southern Hemisphere)? Is it really 0 to 90 degrees for each, and is the 24 K area weighted?

    12. In your discussion of recent correlations of CO2 and temperature, again I do not see how your argument makes your case. The main driving forces on short time scales are the diurnal and seasonal cycle of solar radiation, ocean-atmosphere interactions (thermal delay, and events such as El Nino, etc.), volcanic eruptions, etc. Greenhouse gases have a slow cumulative effect. And, indeed, biological activity is the cause of the annual cycle of CO2 in the NH and the reason the cycle is smaller in the Southern Hemisphere.

    13. In the paleo section, but talking about the present, you suggest there is no ice core evidence that the CO2 affected the climate. But your CO2 record only takes the concentration up to about 320, so a pretty limited effect, and that did not occur until well after the last sample, which you say is the early 20th century, so again, I don’t see how you can rule out a CO2 influence.

    14. On the persistence of heating by water vapor and not CO2—I was confused. In any case, what matters a lot is that water vapor is quite dominant in the lower troposphere, but since CO2 is well-mixed vertically, it has a stronger relative influence aloft, with changes being quite important in the upper troposphere (the effect of which is then carried to the surface by the requirement for less draining of surface energy to support the moist-convective lapse rate).

    15. On nuclear winter, on which I worked, it is quite easy to show that if smoke in the upper troposphere were to cause absorption of all solar radiation, so no solar radiation is reaching to below where most water vapor is, then temperatures underneath will be essentially isothermal and at the radiating temperature of the planet (so 255 K, so Turco, Sagan, et al. froze the world—their model lacked any ocean heat capacity). This would also turn off convection, so there would be a greatly slowed removal process, so the effect could be long lasting. But, it is hard to get that much smoke aloft, and there is an ocean with a lot of heat capacity, hence the discussion evolved toward a ‘nuclear autumn’ or ‘nuclear drought’—even for a big exchange and a lot of smoke.


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    George,

    Nice slide show. Thanks.

    Mike MacCracken: I haven’t looked closely at the sea level stuff yet but have a look at Thermopylae nowadays. Also the site of the Battle of Hastings. It seems sea level rise will only be a problem at locations that are currently vulnerable to storm surges and tsunamis.
    Thanks for asteroid impact stuff.

    Regardless of the reality or otherwise of sea level rise (not evident where I used to go surfing 40 years ago) what evidence is there that the alleged current warming or sea level rise is linked to anthropogenic CO2?

    This is still conjecture based on the coincidence of the end of the LIA and the industrial revolution. In any case why would anyone expect that the global average temperature or sea level rise remain relatively constant over periods of years decades and centuries? As for the alleged acceleration since 1993, you yourself in a earlier post claimed we should be careful of short term data series.

    From what I can see attempts to regulate CO2 emissions will have little effect on CO2 levels in the atmosphere and far less on the global average temperature let alone on sea level rise. What they may do is end our technological civilization or at least lead to the downfall of the west. That last doesn’t need any help to happen and may well prevent the human race’s ability to do something about a NEO encounter.

    So why do it? I see a political issue conjured out of thin air, money making opportunities likewise and scientific careers enhanced and given relevance by,yep,thin air. I really don’t mind self interest or trying to get ahead but don’t do it at other people’s expense, heedless of the widespread damage you can do while catering to self interest.


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    Mike MacCracken

    Dear Mike B (42)–So, as I understand your views, everything is just natural variability doing its thing? Is it all just random, or are you asserting there are natural causes? The energy trapping caused by the human-related emissions of greenhouse gases and changes in atmospheric composition are larger than those estimated from changes in solar radiation and changes in volcanic aerosol loading, so you have to be arguing that small natural changes cause large climate change (so somehow the amount of energy does not determine the magnitude of the response–not impossible, but please do explain) or there is another cause that we don’t understand or its random–and in all cases that somehow this is all happening just at the same time as the industrial revolution and with just the right magnitude, and that this has not for some reason happened during at least the last several thousand years.

    Perhaps not impossible, but it would seem to be pretty low odds to be betting the natural environment and its many services on. A bit like thinking that a case of cancer will just naturally clear itself up, to my way of thinking.

    And on the effects of sea level rise–with sea level virtually constant for many millennia, the coastline has gotten pretty armoured against the present waves, etc. But raise sea level up a few feet, and it is not at all clear that there will be similar protection. Perhaps you’d be interested in some Florida real estate right now–as a long-term investment. Or, better yet, how about some Inuit villages located on frozen barrier islands–you can bet that sea ice retreat will stop, and its role in suppressing waves of autumn and winter storms will return and rescue these villages from loss by erosion (relocation is estimated by the US Government Accountability Office–a Congressionally affiliated office–likely to cost 0.5 to 1 million dollars per person in that homes and all community facilities will have to be rebuilt somewhere else). Your willingness to be that this is just a random fluctuation could be a great source of the funds to pay for this.


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    Mike MacCracken, are you really trying to claim that your climate models really account for all physical variables? Do you think our knowledge of the Earth/Sun/Moon/Galaxy system is that complete?

    What about the Minoan, Roman and Medieval warm periods? What caused them? Do your models account for them? Or are you denying past warmer periods in the Holocene? The Holocene optimum?

    As it seems there is still a large amount of dispute over the temperature rise that extra CO2 will cause(feedbacks), your linking of the magnitude of the current alleged rise(I say alleged because of the known measurement problems and lack of consistent long term measurements)to increased CO2 levels seems disingenuous at best. I don’t think most of the people here are that gullible.

    Now that’s the first time I’ve heard that sea level has been virtually constant for millenia. I guess compared to the changes that occur when entering and exiting glaciations it is, but that also applies to the present rise. I live at 2100 feet above sea level,not because I think the seas will rise, (a surf beach at the bottom of the hill would be nice, though) but I believe Al Gore recently bought waterfront property in San Francisco and Kevin Rudd, the Australian Prime Minister, bought beachfront property on the Sunshine Coast north of Brisbane. I guess they are both not worried about sea level rise then? Both seem very keen on Emissions Trading Schemes.

    As for a few Inuit villages, relocating them will be extremely cheap compared to what you’re planning to do to the world economy and in any case it isn’t at all clear that the coastal erosion you are talking about has anything to do with a little extra CO2 in the atmosphere. That is just an assumption you keep making.

    I sure hope LLNL’s nuclear weapons designers are better than their climate scientists. They seem potentially less harmful anyway.


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    Mike MacCracken

    To Mike (44)–I don’t think I said we understand everything–I agree that we don’t, but you should not also be assuming that you know that there was a global Little Ice Age as you seem to be thinking about it, and same with other climate variations. The North Atlantic is one of the most variable regions–it is not at all clear that other regions change so much, and in fact the 1930s warming in that area was pretty clearly regional and did not extend even across the whole Arctic. So, be careful of your assumptions about the climate system as well.

    And similarly on the policy side. There are many different views about the likely cost of changing, and a very interesting paper of a decade or so ago looked at how the different economic analyses were getting such different results (from nearly no influence to building up to a few percent of the GDP–that is about a one year delay in per capita wealth to save the world). The key reason for the differences was the assumptions that were made, whether the benefits of limiting climate change were accounted for, how the revenues from taxes or permits were utilized and distributed, and more–for Nordhaus and Stern, it is how to weigh the future, so differences in discount rates–so the assumptions are the main difference. Hence, we need to be careful of what we assume.

    And then there is the issue of one’s framing of the question–is what is happening natural until there is some sort of 99% confidence or more that it is not. That is a nice traditional hypothesis testing view. If a business person took that view, they’d be left way behind in the marketplace–that is not how public policy and economic decisions are typically made, and it results in taking a tremendous risk with a very valuable asset, namely our Earth.

    I am not saying it is wrong to do this–only that I think that you (like all the rest of us) have an obligation to then explain to everyone that that is the decision framework that you are using so that they can decide if they want to use the same decision framework. IPCC has tried to carefully explain what its words mean so that those reading its results can then make their own judgments if the science is well-enough understood to make a decision. I do imagine that you have fire insurance on your home, though that risk is quite uncertain and you would not want to wait until you were certain your house were on fire before getting it.

    So, I would only say that it is important to be careful of one’s assumptions (be equally skeptical of everything) and explain one’s decision framework. We should all try to do this.


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    Mike MacCracken:

    The Little ice age didn’t have to be global. It just had to be where most of the thermometers were, if you get the point. There seems to be good evidence for the other periodic warmings which clearly didn’t have much to do with human activity. You have not explained those.

    The AGW arguments seem highly contrived at best. After several years of reading about this I’m convinced there’s nothing terribly significant happening, natural or human caused. Even if the AGW people are correct that there is some human caused global warming due to CO2 the worst case seems to be 1 deg C or so and we’ll be arguing for a long time whether it is 0.3 or 1.1 deg as I see it.

    For this you are proposing a wholesale rearrangement of the world economic system with the creation of energy ” sacred cows”, the burning of fossil fuels. This would be far more convincing if The Climate Institute was advising governments on how to move to nuclear electricity generation.

    I’m not an economics expert but my understanding is that Stern’s discount rate assumptions are a joke.

    Your preferred plan seems to be “lets do something, something might be happening!”. The human race has certainly suffered from mass delusions before (religion in various supernatural or political guises) so this doesn’t seem all that unusual. It’s just difficult to do business with the insane and/or evil.


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    co2isnotevil

    Mike, regarding post 41,

    You’ve asked a number of good questions. I’ve paraphrased some and answered them below.

    1) Where does the carbon go?

    The oceans play a role, however; rain is more important relative to scrubbing CO2 from the atmosphere. Biology sequesters a sizable fraction of the carbon it consumes. Most of this is in the form of biomass falling to the ocean bottom where it decomposes in an oxygen depleted environment, ultimately producing methane ices and after millions of years, fossil fuels. If not enough CO2 is being returned to the atmosphere to replace that sequestered by biology, CO2 levels will fall. When temperatures are falling, the ecosystem shrinks due to habitat shrinkage. Because of the higher CO2 levels from when the temperatures were higher, the remaining biomass will will be consuming and sequestering CO2 at the same higher rate as before, but the CO2 returned through decomposition will not be enough to keep up, ultimately causing CO2 levels to drop and biomass to drop further, until a new steady state level is achieved. The opposite happens as the temperatures rises. This predicts that the delay between temperature changes and CO2 changes will be larger when the temperature is falling, which is consistent with the ice core record. Keep in mind that the steady state atmospheric CO2 concentration level is a function of 2 relatively large fluxes, CO2 entering the system and CO2 being consumed by the system.

    2) How do you handle the ocean?

    The oceans are divided into 3 parts. The deep ocean, the thermocline and the upper layer. If you draw an isotherm whose temperature is the average temperature of the Earth (about the same as the average surface temperature), this will bisect the thermocline. This surface also divides the Earth’s stored thermal energy into 2 energy pools, a warm pool and a cool pool. The average temperature of the warm pool is about the same as the temperature at the boundary between the thermocline and the upper ocean. The average temperature of the cool pool is about the same as the temperature at the boundary between the thermocline and the deep ocean. The thermocline is acting as a layer of insulation between them, which is consistent with the tiny energy flow through it. In fact, the energy flowing down is equal and opposite to the energy flowing up from the Earth’s internal heat which could be coincidental, but is more likely the result of a convection current. The consequence is that because only a tiny fraction of the ocean is involved in storing heat (as opposed to storing cold), the oceans respond far faster to energy changes than the long term feedbacks assumed by AGW require. A final point is that the total number of joules stored in the warm and cool portions want to be the same, which should be recognized as an additional constraint on any thermodynamic model and dictates that the cool pool is much larger than the warm pool. The temperature of the cold pool is far less variable than that of the warm pool. This is due to the density profile of water, relative to temperature and pressure and that the bulk of the Earth’s thermal mass is in the oceans.

    3) What about CO2 feedback?

    The only CO2 and temperature specific feedback is the change in ocean solubility caused by changing temperatures. The pre-feedback effect of incremental CO2 on the temperature is quite small. Even using the inflated 3.7 W/m^2 of incremental forcing for doubling CO2, it’s still only about 0.66C. A CO2 related feedback effect would need to double the CO2 by many more times in order to get the prescribed 3C increase. The feedback quantified by the climate sensitivity metric is not specific to CO2, but the feedback effect of a temperature change on a future temperature change. The accepted value of 0.8 means that if the temperature increases by 0.66C, an additional future temperature increase of 2.33C should be expected. Note that biology is a negative feedback. As CO2 accumulates in the atmosphere and biomass expands, more energy goes in to building biomass and less is available to heat the planet, causing cooling.

    4) Don’t orbital variations cancel out over a year?

    No they don’t and this is one of the biggest assumptive mistakes made in models. The 2 hemispheres respond quite differently to energy, as the satellite data shows. This is largely the result of the dynamic reflectivity of ice and snow. Any paleo simulation with a time step greater than or equal to 3 months will not model the asymmetry properly and would explain why the sensitivity doesn’t seem to be there. This is a discrete time model so the Nyquist rate matters. The asymmetry acts over a period of 6 months at the equator and 12 months elsewhere. To resolve the 6 month effect, the sample period must be less than 3 months, but not so small that the chaos of weather must be accurately modeled.

    5) Did orbital variability cause the Younger Dryas and not a shutdown of the thermohaline circulation?

    Yes. This would also be more consistent with the difference between the southern and northern hemispheres timing of the event.

    6) How are the hemispheric and equatorial regions defined?

    I always use equal angle latitude slices to divide up the planet because that’s how the satellite data I correlate the model to is aggregated. For the slide you mentioned, there are 3 60 degrees slices and all the appropriate weights are handled. In my model, I maintain concurrent representations for all combinations of equal slice widths from, 72 2.5 degree slices to a single 180 degree slice, all of which must be hierarchically consistent with each other.

    7) Doesn’t more of the energy absorbed by CO2 end up reflected to the surface than is radiated into space?

    This question has 2 answers, depending on your temporal perspective. In the very short term, the biggest effect of increasing CO2 is that 15u photons are captured closer to the surface and as the levels increase a slightly higher fraction is returned to the surface. If you consider a time scale of hours to days, then the answer is no since the energy returned to the surface is re-radiated at other frequencies, some of which pass through the transparent regions of the atmospheric absorption spectrum. Ultimately, most of the energy reflected by CO2 to the surface ends up leaving the planet within a day or so. It’s this delayed release, summed up over time, which quantifies the effect of GHG’s on the surface temperature.

    8 ) Don’t GHG’s have a slow accumulative effect on the climate?

    No. This is another incorrect assumption found in many models. Most of the effects of changing GHG concentrations are almost immediate. Only ice related feedback (which applies to any change in the surface temperature) acts over a time frame long enough to even see in the ice cores. The idea that energy hides for a while before affecting the surface temperature arose to explain why the data isn’t cooperating with AGW theory, but has no physical basis and no support from the data. The reason is that the Earth’s energy imbalance is not monotonic. It’s clear from the satellite data that during half of the year, the net imbalance is positive and temperatures increase. During the other half, the imbalance is negative and temperatures drop. It’s also important to remember that the net imbalance is the difference between 2 very large fluxes.

    9) How does the data rule out CO2 as a forcing influence.

    There are several aspects to this. The cross correlation analysis between temperature and CO2 effectively subtracts out the orbital effects. This is evident from the lack of correlation peaks corresponding to the known periods of orbital variability. The only correlation peak in the cross correlation analysis are due to the delay between temperature and GHG levels and shows unambiguously that temperature changes first, CO2 levels follow and CH4 lags by more, with a timescale on the order of centuries. Note that autocorrelating temperature, CO2 or CH4 produces the same correlation peaks corresponding to the known orbital forcing periods. This is clear evidence that CO2 and CH4 levels are dependent on the same orbital forcings as the temperature. Unless you can tell me why orbital variability would affect CO2 levels independent of the temperature, you can’t support the claim that CO2 levels driving temperature is dominant. More evidence is that prior interglacials were far warmer than today, even with significantly lower CO2 levels.

    Enough for now, I have things to do today …

    George


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    Julian Braggins

    Forgive a naive question from a geriatric who has lived long enough to recognize climate cycles first hand.

    I read recently an argument that went roughly as follows,
    Recent probes have found that at 1Bar on Venus , the temperature is comparable to Earth’s, and that Mars surface temperature extrapolated to to 1 Bar is again similar to Earth’s regardless of the high CO2 content of their atmospheres, so in fact basic gas laws account for temperature regardless of GHG’s,
    any comments?


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    Mike MacCracken

    Regarding message 47: Hi George–I got the email you sent directly to me, but am unable to reply as neither the address you used or the one on your Web site will accept my messages.

    Mike MacCracken


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    http://www.descargas-gratis.torrent-informatica.com/ Sitios para descargar juegos gratis o jugar online (flash, PC, PSP, NDS, PS2, wii, xbox360 consolas.La Web en donde vamos a poder descargar directamente juegos para Videoconsolas.Descargar juegos gratis y full. Juegos Gratis.Como Descargar Juegos Gratis PSP Bajar Juegos NDS Foro Descargas.descargar juegos gratis full psp bajar descarga directa gratuita nds foro Como Descargar Juegos Gratis PSP Bajar NDS Foro Descargas


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    Mike MacCracken

    Looking at this analysis again, what I don’t see is any treatment of the ocean as a layered entity that can only slowly absorb heat. Were there no ocean heat capacity, we’d get to equilibrium as quickly as the atmosphere could adjust, so pretty quickly. With infinite heat capacity AND conductance, the ocean temperature would stay the same and heat would be going in. The real situation is in between, of course. With the upper ocean of finite thickness, it heats up a bit, reducing the gradient–and it takes a long time to mix heat down into the deep ocean. Early studies that constructed a one-dimensional diffusive model of the ocean proved inadequate, as the equilibrium temperature would be isothermal, which is not close to observations having a warm surface and cold deep temperature. What has had to be done to make the models work is to create a bypass from the surface to the deep ocean that represents the downward transport of cold water in polar regions, and this creates an upward flow over the ocean as a whole, pushing back up the heat that slowly is diffusing down into the ocean. I would note that if it takes time for heat to push into the deep ocean, then the surface is a bit warmer and radiates more of the heat away.

    A second question is the very limited differentiation of the warming influence of greenhouse gases versus the offsetting cooling influences of aerosols (both long term sulfate loading from SO2 emissions and intermittent volcanic injections). I would also add that the baseline temperature being used internationally to define the 2 C threshold is from preindustrial levels (the recovery from Little Ice Age being a natural cycle is primarily wishful thinking). Now, timing can make a difference–if the GHGs are offset by sulfate aerosols for all but the last year, there would be a different heat uptake than if aerosols were controlled in the 19th century and GHGs were not affected the whole time. Just looking at present conditions to try to do the analysis instead of the path of the change is just not likely to give the right answer.

    It is nice to try a simple schematic approach, but the world is pretty complex. You might try looking at/using the MAGICC model (easy to get on the Web) and actually do the time dependent calculation.


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    That is a wonderful concept. I really believe it will work out to be a valuable piece of information in the future for me.


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