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Post by kenfeldman on May 7, 2009 0:27:53 GMT
Upthread, Pooh posted this image: The tables Pooh has posted above show that the TIM monitor on the SORCE satellite is currently measuring TSI from 10 nm (EUV) to 100,000 nm, or essentially the entire range of the sun's energy output. In addition, there are other monitors on SORCE (and on other satellites) measuring wavelengths as short as 0.1 nm. If we lived in orbit around a blue giant or a red dwarf, Pooh might have a point, but basically he's shown that SORCE is providing the data needed to accurately measure our sun's energy output.
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Post by jimg on May 8, 2009 3:01:52 GMT
kenfeldman:
It's interesting that you posted the current x-ray flux.
Now look at the x-ray flux from 2001-2003.
Soft x-ray flux is down by a factor 10,000.
The assumption on your part is that the energy in watts/m^2 is small and thus x-ray flux is insignificant when it comes to TSI.
Although as TSI is measured, this is true, but again, the assumption is that it is without effect if it doesn not impart heat.
This is a flawed argument in that the sort wavelength energies ionize gases, create NOx and HOx molecules in the atmosphere. Produce ozone, and heat the ionosphere.
How all this works to impact climate is still a big unknown at this time. But to suggest it is without effect because it is small in w/m^2 is a specious argument.
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Post by jimg on May 8, 2009 5:36:42 GMT
I just had a humorous thought.
Warmers' argument against solar influence as the climate driver:
"TSI varies so little that it could not be a significant factor in climate change."
AGW skeptics argument (one of) against CO2 as the driver:
"CO2 represents such a small portion of the atmosphere that it could not be a significant factor in climate change."
Irony?
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jtom
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Post by jtom on May 8, 2009 11:07:44 GMT
The butterfly effect. "Small variations of the initial condition of a dynamical system may produce large variations in the long term behavior of the system."
I guess the debate could be represented by two butterflies duking it out. I'm pulling for a draw.
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Post by steve on May 8, 2009 11:40:56 GMT
I just had a humorous thought. Warmers' argument against solar influence as the climate driver: "TSI varies so little that it could not be a significant factor in climate change." AGW skeptics argument (one of) against CO2 as the driver: "CO2 represents such a small portion of the atmosphere that it could not be a significant factor in climate change." Irony? AGW sceptics argument for solar as a driver: While TSI changes might be relatively tiny, there are probably bigger side effects due to effects on the upper atmosphere/cosmic rays/moonbeams that we don't know about that will mean the effects are much *larger* than just TSI. AGW sceptics argument against CO2 as a driver While CO2 by itself might cause a small amount of warming, there are probably big side effects due to more convection/fluffier clouds etc. that we don't know about that will mean the effects are much *smaller* than just CO2.
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Post by gettingchilly on May 8, 2009 22:44:41 GMT
(steve) AGW fanatics argument for solar as a driver:
TSI = constant, just forget it.
AGW fanatics argument for CO2 as a driver
TSI = constant, we just forgot it. What else is there?
Must be CO2! That'll do.
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Post by steve on May 9, 2009 17:39:49 GMT
gettingchilly,
jimg and I were funnier than you because we told the truth (except about the moonbeams, I'll admit).
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Post by kenfeldman on May 11, 2009 19:24:56 GMT
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Post by stranger on May 11, 2009 20:28:07 GMT
The problem with saying "total solar irradiance is constant" is twofold.
First, we know from a variety of sources that the sun is somewhat less luminous in the visible range than it was 140 years ago. At that time extinction photometers were in existence, carefully hand calibrated, and permanently engraved. Trials with a variety of subjects with fully dark adapted vision demonstrates the extinction point is reached with somewhat less density now than in the period just after the United States War of Southern Secession.
This probably underestimates the total diminution since the instruments were intended for use by field photographers with only minimal dark adaptation, working under hoods that were not completely light tight.
Second, we also know that amount of the most energetic radiation from the Sun, the extended UV spectrum, has declined dramatically in the last few years. As I remember the equation, the formula for the energy in each photon is
E = pF where E is energy, p is Planck's constant, and F is the frequency.
Since UV has a shorter wavelength than visible light, it obviously has a higher frequency, and far more energy per photon that infrared (heat), and visible light. Since virtually all UV is absorbed and converted to heat, a substantial loss of UV radiation must result in substantially less solar heating.
Therefore, any flat statement about the constancy of solar irradiance is highly suspect. Or, if you prefer, incorrect.
Stranger
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Post by kenfeldman on May 11, 2009 23:45:44 GMT
Climate scientists are aware that the sun varies over time and that the solar constant is not truly constant. They have made considerable efforts to understand the sun's impact on the climate, and have concluded that changes in the sun can't account for the observed changes in the climate in recent decades.
Here is a quote from the IPCC Fourth Assessment Report, which summarizes the science behind AGW, with respect to solar forcing, UV and possible climate impacts:
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Post by kenfeldman on May 12, 2009 0:00:50 GMT
While probably meant to be amusing in the context of this thread, I've seen this arguement used by deniers in other places. It is wrong of course.
The basic arguement behind AGW is firmly founded in quantum mechanics (radiation physics) and the conservation of energy.
Unless deniers can show that either of those two basic physical principles don't apply to the earth's climate, AGW is a problem if we continue to increase the concentrations of greenhouse gases in the atmosphere. There have been no magical negative feedbacks discovered that keeps the earth within a few degrees of the fairly stable temperature ranges that we've had for the past 10,000 years.
In the past decade, it's been shown that climate can change rather abruptly due to relatively small changes in forcings, and the increase in greenhouse gas concentrations is much larger than those forcings that caused the past episodes of abrupt climate change.
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Post by ron on May 12, 2009 2:00:10 GMT
Here is a quote from the IPCC Fourth Assessment Report, which summarizes the science behind AGW, with respect to solar forcing, UV and possible climate impacts: Isn't this saying that they've observed an correlation, but the computer models don't reproduce the measured effect? In other words, the computer models are wrong? Just wondering.
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jtom
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Post by jtom on May 12, 2009 2:52:56 GMT
The one thing that I keep coming back to is that the climate has not gotten warmer over the last decade or so (you can argue as to whether it's actually cooler, doesn't matter).
IF the warm-up during the '90s was a result of CO2, then either CO2 warming has hit a saturation point, or something(s) driving the climate that is at least as strong as CO2. Let's assume the latter.
Several studies indicate solar influence is not a strong driver. OK, so what's left? The ocean? No, it appears to have begun cooling during this same period. What 'natural variation' is strong enough to absorb ten years' worth of CO2 stored energy or reflect enough solar energy to counter the CO2 effect? The energy has to be somewhere. It's either here on earth, and we should be able to measure it, or it's been sent on its way into space.
If no one can pinpoint what is going on, then we are left to conclude that there are so many variables, forcings and drivers that the climate follows chaotic dynamics. A small change in something (solar IR, solar wind, cosmic rays, atmospheric content) eventually causes significant changes in the climate. If that is the case, then forget the models, the climate's not predictable.
My hunch is the climate exhibits chaotic behavior around a strange attractor, a Lorentz attractor, specifically, just as weather evidently does, and certain fundamental changes (position of land masses, atmospheric water vapor or CO2 levels, solar anomaly, etc.) can change the center-point of the attractor. If so, then there is just as good a chance that increased CO2 is about to lessen the impact of an on-coming ice age as there is that it will 'worsen' (I find it debatable whether warming is actually bad) a warming trend.
On a last note, I find it somehow both fitting and ironic that chaotic behavior around a Lorentz attractor gives rise to a pattern that looks like butterfly wings - the same pattern as Maunder's sunspot butterfly diagram.
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Post by poitsplace on May 12, 2009 5:35:16 GMT
The basic arguement behind AGW is firmly founded in quantum mechanics (radiation physics) and the conservation of energy. Unless deniers can show that either of those two basic physical principles don't apply to the earth's climate, AGW is a problem if we continue to increase the concentrations of greenhouse gases in the atmosphere. This assumes you put on blinders though and ignore all sorts of other affects. The ABSOLUTE MAXIMUM without feedbacks should be about 1.5C for a doubling of CO2. But water vapor is a much more common gas and overlaps CO2's spectrum. With such high concentrations that overlapped portion of CO2's spectrum can't increase temperatures at all. At least half of the energy that CO2 DOES manage to capture either gets radiated away without "thermalizing" or gets tied up with water. Of the energy that "thermalizes" about 1/2 of it immediately radiates out into space. You just can't use that absorption math...because it doesn't apply. And there have been no "magical" positive feedbacks discovered that would significantly amplify CO2's supposed forcing. We've already had 30% of the warming projected by the oversimplified physics with absolutely no sign of those supposed feedbacks. TECHNICALLY though, because of the logarithmic nature of absorption, the increases we've observed should actually account for nearly 1/2 of the total warming. There is no way to explain the LACK of warming unless feedbacks are neutral to negative. Almost all projections by the IPCC are flat out disproven by the observed data. It can't be claimed that there is heat "in the pipe" because temperatures have actually started falling...including phenominal losses of overall ocean heat. Oh, I suppose there is ONE explanation that would fit. It could be that we've just averted another little (or proper) ice age.
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jtom
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Post by jtom on May 12, 2009 10:44:20 GMT
Conservation of energy, exactly. So where has the captured energy from the increasing levels of CO2 been hiding for the past decade?
There have been no magical negative feedbacks discovered that keeps the earth within the few tenths of a degree of the fairly stable temperature that we've had for the past decade despite ever growing CO2 levels.
So which is it, negative feedbacks exist, or CO2 does not drive the climates as the models claim?
Can't have it both ways, kenfeldman.
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