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Post by dmapel on Jun 10, 2009 16:41:11 GMT
glc: “Ok but I'll need a bit of time but here a re a few brief comments.”
Thanks for your response and I am looking forward to seeing more.
glc: “I think these both give a figure that is too low (i.e. ~0.2 deg per w/m2). However, it should be noted that even this low figure gives a total warming of ~0.7 deg which is not a million miles from my ~1 deg estimate.”
I am willing to stipulate the ~1 deg estimate. That’s another battle I don’t see as needing to be fought. However, I am still waiting to see some real World evidence that even 1 deg is “very likely” to actually materialize. glc: “I doubt if JB is putting this forward as a robust figure - more as an indicator that IPCC sensitivity is too high.”
Don’t the AGW proponents use volcanoes, and other variable and transitory sources of aerosols as excuses for canceling out part of the effects from increased CO2 forcing? How do they do it? Are their calculations robust?
glc: “Imagine it is -10 degrees outside. Now place a bucket of water in your garden. Five minutes later you go out to check. The water is still liquid. It is not yet frozen. Does this mean it's not really -10 degrees or water freezes at a much lower temperature. No it just means that the water and air are not "in equlibrium". The water is still losing heat.”
Yes, but I could expect to have ice in thirty years, if the air did not get significantly warmer. And when the water loses heat, it doesn’t go hang out for thirty years in some imaginary pipeline. It goes into the air and forms a hot spot that clever climate scientists should be able to find with balloons and thermometers. And when they don’t find it with thermometers, they just say that thermometers don’t work right, a wet finger in the wind will do a much better job of finding missing heat. The point I am getting at is the AGW proponents have been telling us for decades, that based on their settled science and clairvoyant climate models, it is supposed to be getting hotter. I don’t see it. Could it be that the climate is not as sensitive as settled science says it is? Could the models be wrong? Could we have just been bouncing around “equilibrium” for the last thirty years, and we are now back to steve’s famous “average conditions”?
Anyway, I appreciate your willingness to engage in an honest discussion. I don’t believe that you are so far away from the truth that you won’t find it some day. At least, you certainly don’t appear to be blinded by the dogma.
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Post by glc on Jun 10, 2009 17:28:35 GMT
Don’t the AGW proponents use volcanoes, and other variable and transitory sources of aerosols as excuses for canceling out part of the effects from increased CO2 forcing? How do they do it? Are their calculations robust?
But you do need to consider at what point equilibrium has been (or will be) reached. Jack Barrett did a quick, back of the envelope of the envelope calculation to show that the IPCC sensitivity estimates are too high.
Yes, but I could expect to have ice in thirty years, if the air did not get significantly warmer. And when the water loses heat, it doesn’t go hang out for thirty years in some imaginary pipeline
Agreed. But I was making the point about Pinatubo. If the aerosols from the eruption had stayed in the atmosphere for longer then we'd probably have seen further cooling. This implies Jack's sensitivity calculation (0.19 deg per w/m2) is a bit on the low side.
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Post by glc on Jun 10, 2009 17:55:56 GMT
Do I sense a bit more hubris in your musings as time goes on?I don't know. On the subject of climate sensitivity, you have inferred to have it all figured out. I don't think I've got it " all figured out". I think that a sensitivity of ~0.3 deg per w/m2 fits reasonably well with known observations. For example, since the 1940s (the last time we had a +ve PDO) global temperatures have risen by ~0.5 deg. The forcing due to CO2 increases is ~1.6 w/m2 which gives a very rough estimate of ~0.32 deg per w/m2. I wouldn't suggest this means a great deal but it does a bit more weight to the low/no feedback argument. Please, in your own words, analyze Lindzen's recent presentation based on observations vs models. I don't have the audio portion, but have posted the PPT where he states wattsupwiththat.files.wordpress.com/2009/06/richard-lindzen-3.pptProblem is I don't currently have access to Powerpoint. What we see, then, is that the very foundation of the issue of global warming is wrong.I doubt very much we'll see that. We might see something which raises questions, but it's unlikely that this or any other single piece of work is going to settle the issue one way or the other.
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Post by dmapel on Jun 10, 2009 18:03:59 GMT
glc: "But you do need to consider at what point equilibrium has been (or will be) reached. Jack Barrett did a quick, back of the envelope of the envelope calculation to show that the IPCC sensitivity estimates are too high."
Do the climate models do a significantly better job of calculating the effects of transitory aerosols?
glc: "Agreed. But I was making the point about Pinatubo. If the aerosols from the eruption had stayed in the atmosphere for longer then we'd probably have seen further cooling. This implies Jack's sensitivity calculation (0.19 deg per w/m2) is a bit on the low side. "
OK, I will agree there is the implication that 0.19 is a bit on the low side. On the other hand, the continuing accumulation of gazillions of tons of CO2 in the atmosphere, along with no significant rise in temperatures over a multi-decadal time scale, implies that the IPCC sensitivity number is BS.
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Post by poitsplace on Jun 10, 2009 18:42:17 GMT
GLC has stated numerous times that he believes there is warming...and he catches hell from most AGW proponents because the figures he uses are...basically what has been observed.
I believe he has also stated before that those figures don't seem alarming to him.
Just thought I'd toss that out there in case some hadn't heard or had forgotten
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Post by magellan on Jun 10, 2009 18:54:43 GMT
Do I sense a bit more hubris in your musings as time goes on?I don't know. On the subject of climate sensitivity, you have inferred to have it all figured out. I don't think I've got it " all figured out". I think that a sensitivity of ~0.3 deg per w/m2 fits reasonably well with known observations. For example, since the 1940s (the last time we had a +ve PDO) global temperatures have risen by ~0.5 deg. The forcing due to CO2 increases is ~1.6 w/m2 which gives a very rough estimate of ~0.32 deg per w/m2. I wouldn't suggest this means a great deal but it does a bit more weight to the low/no feedback argument. Please, in your own words, analyze Lindzen's recent presentation based on observations vs models. I don't have the audio portion, but have posted the PPT where he states wattsupwiththat.files.wordpress.com/2009/06/richard-lindzen-3.pptProblem is I don't currently have access to Powerpoint. What we see, then, is that the very foundation of the issue of global warming is wrong.I doubt very much we'll see that. We might see something which raises questions, but it's unlikely that this or any other single piece of work is going to settle the issue one way or the other. powerpoint viewer for Windows, or OpenOffice will work. www.microsoft.com/downloads/details.aspx?FamilyId=428D5727-43AB-4F24-90B7-A94784AF71A4&displaylang=en
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Post by magellan on Jun 10, 2009 19:03:41 GMT
So you are saying the IPCC has the wrong definition of a forcing? Whose definition are you using? I will say you are correct that the 3.7watts/m2 is the least controversial part of the AGW theory. Thats because everybody agrees on the sign. Everybody agrees that more CO2 is a positive forcing on atmospheric temperature. Please folks, humor me just for a moment. If AGW warms the oceans, how and how much? I only understand numbers. www.cdc.noaa.gov/people/gilbert.p.compo/CompoSardeshmukh2007a.pdfI was hoping someone would respond, but no takers. It's not new; maybe ocean warming has been lost in the fog of GHG. Let's try again: www.cdc.noaa.gov/people/gilbert.p.compo/CompoSardeshmukh2007a.pdfWith the Abstract: Abstract Evidence is presented that the recent worldwide land warming has occurred largely in response to a worldwide warming of the oceans rather than as a direct response to increasing greenhouse gases (GHGs) over land. Atmospheric model simulations of the last half-century with prescribed observed ocean temperature changes, but without prescribed GHG changes, account for most of the land warming. The oceanic influence has occurred through hydrodynamic-radiative teleconnections, primarily by moistening and warming the air over land and increasing the downward longwave radiation at the surface. The oceans may themselves have warmed from a combination of natural and anthropogenic influences. If CO2 can cause the oceans to warm at the rate observed for the last 20+ years, where are the calculations to explain it?
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Post by dmapel on Jun 10, 2009 21:27:44 GMT
poitsplace: "GLC has stated numerous times that he believes there is warming...and he catches hell from most AGW proponents because the figures he uses are...basically what has been observed.
I believe he has also stated before that those figures don't seem alarming to him.
Just thought I'd toss that out there in case some hadn't heard or had forgotten"
I have noticed that glc seems to be quite reasonable, honest, and willing to engage in debate. That is why I haven't subjected him to ridicule as I may be inclined to do to dogmatic, disingenuous warmistas.
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Post by icefisher on Jun 10, 2009 22:20:41 GMT
www.cdc.noaa.gov/people/gilbert.p.compo/CompoSardeshmukh2007a.pdfWith the Abstract: Abstract Evidence is presented that the recent worldwide land warming has occurred largely in response to a worldwide warming of the oceans rather than as a direct response to increasing greenhouse gases (GHGs) over land. Atmospheric model simulations of the last half-century with prescribed observed ocean temperature changes, but without prescribed GHG changes, account for most of the land warming. The oceanic influence has occurred through hydrodynamic-radiative teleconnections, primarily by moistening and warming the air over land and increasing the downward longwave radiation at the surface. The oceans may themselves have warmed from a combination of natural and anthropogenic influences. If CO2 can cause the oceans to warm at the rate observed for the last 20+ years, where are the calculations to explain it? Steve has the answer: "Most of the air is colder than the ground, and layers of air are normally colder than the layers of air below. So if a given layer (within which no condensation or evaporation takes place) receives, say 130 units of energy from below, 70 units from above, it will reemit 200 units - half of them up and half of them downwards." So obviously those photons playing pingpong finally land in the ocean and heat it up. . . .all you have to do eliminate or sufficiently push aside all conduction, convection, or IR by anything other than CO2, add a blocking to ground absorption of CO2 frequencies and viola you have a model!! When somebody comes around with a thermometer of the ocean something then sucks all that heat into the Marianna's trench where there are no thermometers. As Colonel John Smith sez: "I love it when a plan comes together"
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Post by glc on Jun 10, 2009 23:05:01 GMT
If CO2 can cause the oceans to warm at the rate observed for the last 20+ years, where are the calculations to explain it?
CO2 doesn't warm the oceans directly. It can, though, slow the nomal rate of cooling. It's certainly possible to get the numbers to stack up.
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Post by icefisher on Jun 10, 2009 23:26:26 GMT
If CO2 can cause the oceans to warm at the rate observed for the last 20+ years, where are the calculations to explain it?CO2 doesn't warm the oceans directly. It can, though, slow the nomal rate of cooling. It's certainly possible to get the numbers to stack up. Hmmmm, how does that work GLC?
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Post by woodstove on Jun 11, 2009 0:12:15 GMT
If CO2 can cause the oceans to warm at the rate observed for the last 20+ years, where are the calculations to explain it?CO2 doesn't warm the oceans directly. It can, though, slow the nomal rate of cooling. It's certainly possible to get the numbers to stack up. Any chance that comes from realclimate, glc?
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Post by glc on Jun 11, 2009 8:16:53 GMT
Icefisher: Hmmmm, how does that work GLC?
By simple physics. Do you not think it's possible that the presence of a body at a certain temperature can slow down the rate of cooling of a warmer body? Rather than offer my own explanation, this is what Roy Spencer writes on the issue:
"Furthermore, we should not confuse a reduced rate of cooling with heating. Imagine you have a jar of boiling hot water right next to a jar of warm water sitting on the counter. The boiling hot jar will cool rapidly, while the warm jar will cool more slowly. Eventually, both jars will achieve the same temperature, just as the 2nd Law predicts.
But what if the boiling hot jar was by all by itself? Then, it would have cooled even faster. Does that mean that the presence of the warm jar was sending energy into the hot jar? No, it was just reducing the rate of cooling of the hot jar. The climate system is like the hot jar having an internal heating mechanism (the sun warming the surface), but its ability to cool is reduced by its surroundings (the atmosphere), which tends to insulate it."
I'm not entirely happy with his wording in the 2nd paragraph. The main point, though, is that although the net flow of energy is away from the 'hotter' jar it is slowed by the presence of the 'less warm' jar.
Woodstove: Any chance that comes from realclimate, glc?
Because RC say it doesn't mean it's not true. Any black body above 0 kelvin (-273.15 deg C) emits energy. This is given by the Stefan-Boltzmann law, i.e.
E = sigma x T4
where sigma (S-B constant) = 5.67 x 10-8 and T is temperature in degrees kelvin. The law also holds for non-black (or grey) bodies but the equation then includes an emissivity factor (e or epsilon).
The principle is the same, though. Hotter bodies emit more than colder ones. If the atmosphere warms it will emit more LW radiation to the surface. The LW radiation cannot penetrate more than a few micron into the ocean 'skin', but it can reduce the net flow of energy from the ocean which means that more heat will be retained in the ocean. The fact that the atmosphere is cooler than the ocean is irrelevant. It will still emit radiation according to the S-B law. Roy Spencer uses the examples of stars to make this point, i.e.
"In other words, a photon being emitted by the cooler star doesn’t stick its finger out to see how warm the surroundings are before it decides to leave."
Plus - as I said in an earlier post, it's trivial to show that the numbers do stack up, so the theory (or hypothesis) does hang together. That said, I still have a bit of a problem with it.
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Post by poitsplace on Jun 11, 2009 10:40:41 GMT
True BUT...part of the reason the water is cooler in the first place is that it has a second mechanism to eliminate the heat. While dry ground has to get significantly hotter to reach equilibrium, the ocean (and all bodies of water) start releasing water vapor which temporarily sidelines the energy as latent heat and carries it to a region where it can be emitted.
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Post by icefisher on Jun 11, 2009 19:08:33 GMT
Icefisher: Hmmmm, how does that work GLC? By simple physics. Do you not think it's possible that the presence of a body at a certain temperature can slow down the rate of cooling of a warmer body? Rather than offer my own explanation, this is what Roy Spencer writes on the issue: "Furthermore, we should not confuse a reduced rate of cooling with heating. Imagine you have a jar of boiling hot water right next to a jar of warm water sitting on the counter. The boiling hot jar will cool rapidly, while the warm jar will cool more slowly. Eventually, both jars will achieve the same temperature, just as the 2nd Law predicts.
But what if the boiling hot jar was by all by itself? Then, it would have cooled even faster. Does that mean that the presence of the warm jar was sending energy into the hot jar? No, it was just reducing the rate of cooling of the hot jar. The climate system is like the hot jar having an internal heating mechanism (the sun warming the surface), but its ability to cool is reduced by its surroundings (the atmosphere), which tends to insulate it."I'm not entirely happy with his wording in the 2nd paragraph. The main point, though, is that although the net flow of energy is away from the 'hotter' jar it is slowed by the presence of the 'less warm' jar. Woodstove: Any chance that comes from realclimate, glc?Because RC say it doesn't mean it's not true. Any black body above 0 kelvin (-273.15 deg C) emits energy. This is given by the Stefan-Boltzmann law, i.e. E = sigma x T 4 where sigma (S-B constant) = 5.67 x 10 -8 and T is temperature in degrees kelvin. The law also holds for non-black (or grey) bodies but the equation then includes an emissivity factor (e or epsilon). The principle is the same, though. Hotter bodies emit more than colder ones. If the atmosphere warms it will emit more LW radiation to the surface. The LW radiation cannot penetrate more than a few micron into the ocean 'skin', but it can reduce the net flow of energy from the ocean which means that more heat will be retained in the ocean. The fact that the atmosphere is cooler than the ocean is irrelevant. It will still emit radiation according to the S-B law. Roy Spencer uses the examples of stars to make this point, i.e. "In other words, a photon being emitted by the cooler star doesn’t stick its finger out to see how warm the surroundings are before it decides to leave."Plus - as I said in an earlier post, it's trivial to show that the numbers do stack up, so the theory (or hypothesis) does hang together. That said, I still have a bit of a problem with it. OK but you haven't answered the question. If the ocean is warming the land, how did the ocean get warmer than the land in the first place? Its well known that the terrestrial environment is far more sensitive to warming or cooling than the ocean environment. Presumably if CO2 emissions are merely slowing down cooling it would be having more effect on land than the ocean because of that well known sensitivity factor. . . .but if we started at an equilibrium how is it that the land is not warmer from direct CO2 emissions than the ocean causing the reverse effect from what was observed above? The obvious answer would have to be that we were not in equilibrium to begin with . . . .giving additional support for Akasofu:
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