Solar Minumums vs. Solar Maximums

[WeatherNC]

This is a thread about solar mins and max, and the role on our climate, not a place for starting arguments and insulting other members on why they disagree with you about the mechanism behind global warming. If you want, start a new thread to carry on the debate, otherwise take the crap elsewhere as it does not belong in this one. Thanks

[BethesdaWX]

You catch more flies with honey than with vinegar.

I catch more Skiers with Vinigar than with Honey.

[BethesdaWX]

This is a thread about solar mins and max, and the role on our climate, not a place for starting arguments and insulting other members on why they disagree with you about the mechanism behind global warming. If you want, start a new thread to carry on the debate, otherwise take the crap elsewhere as it does not belong in this one. Thanks

ok

[weatherdude]

Just wait a little bit, and WeatherRusty will reproduce his figures showing how the CO2 forcing overwhelms any forcing from the sun. In case you didn't remember, he did post those figures a week or 2 ago. I don't remember which thread though, so again we must wait. I find it reasonable to request of you, because afterall we must wait until 2045 to try to convince you.

Keep an open mind and you might be convinced this month...and next...and next winter...

[aslkahuna]

One has only to look at Venus to see the impacts of high (impossibly high on Earth) CO2 concentrations.

More to it than that though. Earth also had much higher concentrations of both Methane and Carbon Dioxide which kept the planet warm during the Sun's pre and early main sequence stage when it was less luminous. The development of plants with CO₂->O₂ photosynthesis was key in altering our atmosphere whereas Venus never got there. Additionally, Venus has different global tectonics, no significant magnetic field, very slow retrograde rotation, and also important, no good sized satellite in orbit around it. It is also 26 million miles closer to the Sun.

Steve

[aslkahuna]

You catch more flies with honey than with vinegar.

Fecal matter works best though

Steve

[salbers]

Yes, apparently Earth can't have a runaway greenhouse since the solar radiation is less at our distance. However Venus does help provide a good real-world example of what CO2 can do. With the more modest amounts on Earth it still can have a noticeable and significant effect.

[BethesdaWX]

Yes, apparently Earth can't have a runaway greenhouse since the solar radiation is less at our distance. However Venus does help provide a good real-world example of what CO2 can do. With the more modest amounts on Earth it still can have a noticeable and significant effect.

Uhh, Venus is 95% CO2 and Close as hell to the sun. Honestly there is no relation.

We are 0.038%, with millions of other forcings. Yes, CO2 could have a significant impact here....or it could have very little impact... We go over the same points everytime...what CO2 does in a controlled impound experiment has no bearing on the result when its in our atmosphere.

The Hypothesis that CO2 is causing the majority of our warming has not been verified...yet. We'll see where this goes.

[salbers]

Uhh, Venus is 95% CO2 and Close as hell to the sun. Honestly there is no relation.

We are 0.038%, with millions of other forcings. Yes, CO2 could have a significant impact here....or it could have very little impact... We go over the same points everytime...what CO2 does in a controlled impound experiment has no bearing on the result when its in our atmosphere.

The Hypothesis that CO2 is causing the majority of our warming has not been verified...yet. We'll see where this goes.

Interestingly Mars is closer to the Earth in CO2 content, with still a bit more.

http://zebu.uoregon.edu/~soper/Mars/atmosphere.html

Well again the radiative forcing is the same, both in the laboratory and in the atmosphere, where it can actually be observed spectroscopically and such. While other factors do enter in with the real world, the radiative forcing is the one that is steadily increasing and rising above the "noise" of the other factors. If we wait until it is even more obvious it will be too late to reverse it due to lag effects. Why would you want to gamble with the climate's future?

[BethesdaWX]

Well again the radiative forcing is the same, both in the laboratory and in the atmosphere, where it can actually be observed spectroscopically and such. While other factors do enter in with the real world, the radiative forcing is the one that is steadily increasing and rising above the "noise" of the other factors. If we wait until it is even more obvious it will be too late to reverse it due to lag effects. Why would you want to gamble with the climate's future?

That has never been the issue here. We cannot experiment with CO2 like a Chemist can experiment with a Chemical... it doesn't work that way. So, Earths CO2 at 0.038% of the atmosphere, we cannot properly gauge how much of an impact it will have against the complex world of gases & inter-relationships present in our atmosphere.

Its not about the properties of the molecule directly... that has never been the issue! The fact that CO2 is only 0.038% of our atmosphere, we cannot properly estimate how much of an impact it will have except hypothesizing through Computer modeling, attempting to tackle the makeup of our atmosphere, millions of forcings we know little to nothing about...it's as uncertain as ever. In reality, the science behind AGW is shaky at best, & nowhere near settled. Its actually like throwing darts in the dark, plain and simple.

[salbers]

Sure, there are other forcings. However we do know the atmospheric composition, and the radiative forcing is there, can be observed, and is rising. See figure 2-10 for one example of how the greenhouse effect changes can be observed in the real atmosphere:

http://www2.sunysuff...ouse_gases.html

While we're at it figure 2.6 shows Methane was NOT higher during the MWP, though I would note their methane values seem about 10% too high in 2005.

[BethesdaWX]

Sure, there are other forcings. However we do know the atmospheric composition, and the radiative forcing is there, can be observed, and is rising.

You seriously missed....everything. Once again, Co2 being 0.038% of the atmosphere, we Can't gauge its impact over the other thousands of gases & inter-relationships! We cannot expirement like a chemist would with a chemical.

Computer models are hypothesis of their own! We have no other way to get the slightest idea...

Anyone who states we "understand" our atmospheres composition & how it acts in inter-relationship is fooling themselves..there are millions of forcings we know little or nothing about, we will never know how it works....a Trace Gas like CO2 will be impossible to pinpoint..

[BethesdaWX]

Sure, there are other forcings. However we do know the atmospheric composition, and the radiative forcing is there, can be observed, and is rising. See figure 2-10 for one example of how the greenhouse effect changes can be observed in the real atmosphere:

http://www2.sunysuff...ouse_gases.html

While we're at it figure 2.6 shows Methane was NOT higher during the MWP.

Or we have these

http://www.geocraft.com/WVFossils/greenhouse_data.html

http://www.americanthinker.com/2009/01/co2_fairytales_in_global_warmi.html

http://www.atmos-chem-phys.net/10/10941/2010/acp-10-10941-2010.pdf

[salbers]

A quick look at your links (since you weren't specific) shows they add nothing to our discussion of whether the radiative forcing from GHGs can be observed. The link I showed in Figure 2-10 and the following few paragraphs describe several types of observations where GHG radiative forcing is observed in the real-world. What specifically can you offer to refute this?

We can debate whether other factors are also affecting climate, but my point is that anthropogenic GHG radiative forcing does occur in the real atmosphere.

[BethesdaWX]

A quick look at your links (since you weren't specific) shows they add nothing to our discussion of whether the radiative forcing from GHGs can be observed. The link I showed in Figure 2-10 and the following few paragraphs describe several types of observations where GHG radiative forcing is observed in the real-world. What specifically can you offer to refute this?

We can debate whether other factors are also affecting climate, but my point is that anthropogenic GHG radiative forcing does occur in the real atmosphere.

We're going in circles. MY point is that we cannot accurately gauge HOW MUCH of an impact it has, whether it be signficant, or completely insignificant.

I never argued the composition of the molecule & what it can do. We cannot gauge CO2 & its 0.038% against the millions of forcings & inter-relations in our complex atmosphere, excpe through attempts/hypothesis developed in computer models.

We do not understand how our atmospheric composition works through inter-relations & the millions of excess forcings involved.

[salbers]

Well, apparently from the discussion I linked to, the observed radiative forcing in the atmosphere is about the same as what is calculated and measured in the laboratory. This is happening whether there are other things going on or not. And this is getting large enough to overwhelm the other "millions" of forcings you are referring to. The Earth has complexity, yet it seems obvious to me that simple things can push the complex system.

As to whether this is significant, the long term climate sensitivity is around 3C per CO2 doubling (or even more with albedo / methane feedbacks). This seems significant to me. And you've yet to counter my point about the lags in the system. Once the changes are more blatantly obvious to skeptics it may be too late to reverse them. Why would you be in favor of this risky scenario?

How many W/m**2 of GHG forcing would you find acceptable?

[BethesdaWX]

Well, apparently from the discussion I linked to, the observed radiative forcing in the atmosphere is about the same as what is calculated and measured in the laboratory.

As to whether this is significant, the long term climate sensitivity is around 3C per CO2 doubling (or even more with albedo / methane feedbacks). This seems significant to me. And we're not going in circles, since you've yet to counter my point about the lags in the system. Once the changes are more blatantly obvious to skeptics it may be too late to reverse them. Why would you be in favor of this scenario?

Jezuz! Where did I argue that the properties of the molecule & how it works are changed? I didn't. Co2 & its 0.038% may have the same properties, but the end result temperature wise is NOT the same in the atmosphere, due to milions of forcings & complex inter-relations...the formulas given are hypothesis derived from computer models & the presumed impact on earths temperature....that is hypothesis. Its been the same thing with you.... you go on saying how the radiative forcing is this that...etc, but I never argued the properties of the modecule.

This digs only very shallow, but you get the point.

http://icecap.us/images/uploads/Evans-CO2DoesNotCauseGW.pdf

[salbers]

The following post disputes what your link says about the upper tropospheric footprint:

http://www.skeptical...ic-hot-spot.htm

Overall, if you think that Greenhouse gases don't have a significant effect on the Earth, how come we are around 15C warmer than what you'd expect from the simple assumptions of no GHGs at all (either natural or manmade). This fits the types of radiative / temperature effect calculations that you so easily want to dismiss. Clearly GHG's do warm the Earth, and it's a simple concept that more GHGs put in by people will increase this warming. Sure aersols, cosmic rays, solar changes, ocean currents and such will modify the rates of change on short time scales, but eventually they will average out while the GHG signal emerges in its relentless rise. Again, why do you want to risk the planet's future, given the time lags? It seems I'll mention the time lags a thousand times and you'll still ignore them. What kind of discussion is that?

[BethesdaWX]

Well, if you think that Greenhouse gases don't have a significant effect on the Earth, how come we are around 15C warmer than what you'd expect from the simple assumptions of no GHGs at all (either natural or manmade). This fits the types of radiative calculations that you so easily want to dismiss. Clearly GHG's do warm the Earth, and it's a simple concept that more GHGs put in by people will increase this warming. Sure aersols, cosmic rays, solar changes, ocean currents and such will modify the rates of change on short time scales, but eventually they will average out while the GHG signal emerges in its relentless rise. Again, why do you want to risk the planet's future, given the time lags? It seems I'll mention the time lags a thousand times and you'll still ignore them. What kind of discussion is that?

huh? Don't put words into my mouth, I never said GHG didn't have a significant impact, We're just talking about CO2 alone here. About 98% of all CO2 WP is maxed at 400ppm

This isn't even what I was referring to in the 1st place. Our warming to this point is by no means CO2 caused. Again, read my previous post

Where did I argue that the properties of the molecule & how it works are changed? I didn't. Co2 & its 0.038% may have the same properties, but the end result temperature wise is NOT the same in the atmosphere, due to milions of forcings & complex inter-relations...the formulas given are hypothesis derived from computer models & the presumed impact on earths temperature....that is hypothesis. Its been the same thing with you.... you go on saying how the radiative forcing is this that...etc, but I never argued the properties of the modecule.

This digs only very shallow, but you get the point.

http://icecap.us/ima...sNotCauseGW.pdf

[BethesdaWX]

Co2 alone only contributes to a very small portion of the GHE regardless. The entire GHE is completeky different & unrelated at this point.

[salbers]

I agree there is a logarithmic CO2 relationship. While I'm unsure what the 3 lines mean in your graph it still is calculated that a 1.2 deg C per CO2 doubling is the effect. This gets increased to around 3C (with some uncertainty) if you factor in water vapor feedback. I would suggest it could be more than that (in the long term) with albedo and methane feedbacks.

[BethesdaWX]

I agree there is a logarithmic CO2 relationship. While I'm unsure what the 3 lines mean in your graph it still is calculated that a 1.2 deg C per CO2 doubling is the effect. This gets increased to around 3C (with some uncertainty) if you factor in water vapor feedback. I would suggest it could be more than that (in the long term) with albedo and methane feedbacks.

Again, what "calculated" is hypothesis based on computer modeling. Thats the whole point, our warming could be CO2 caused, or naturally caused.

http://www.junkscience.com/Greenhouse/

How much does the so-called 'greenhouse effect' warm the Earth?

It's estimated that the Earth's surface would be about -18 °C (0 °F, 255 K) with atmosphere and clouds but without the greenhouse effect and that the (we'll call it "natural") greenhouse effect raises the Earth's temperature by ~33 °C (59 °F).

We should note that devoid of atmosphere Earth would actually be a less-cold -1 °C (272 K) because the first calculation strangely includes 31% reflection of solar radiation by clouds (which obviously could not occur without an atmosphere) while ignoring that clouds add significantly to the greenhouse effect. Granted it's kind of a bizarre to include clouds in one half the calculation and not the other but that is the way it's commonly done, so, for simplicity, just stick with ~33 °C.

The workings: thermal equilibrium for an Earth without an atmosphere:

The sun behaves approximately like a black body of radius r_s=6.599 x 10⁵ Km, at a temperature of T_s=5,783 K. The radiative flux at the sun's surface is given by the expression σT_s⁴, where σ is the Stefan-Boltzmann Constant (5.6704 x 10^-8 Wm²K⁴). Flux refers to radiation per unit area. Thus, at the Earth's distance from the sun, r_es=1.496 x 10⁸ Km, this flux is reduced by the factor (r_s/r_es)². The Earth's disk has a cross section, a_cs=πr_e², where r_e is the Earth's radius (6.378 x 10³ Km), and thus intercepts a_csσT_s⁴(r_s/r_es)² radiation from the sun. In order to balance this intercepted radiation, the Earth would warm to a temperature T_e, where σT_e⁴4πr_e² = a_csσT_s⁴(r_s/r_es)². This leads to a solution T_e=272 K. Clouds, which obviously require an atmosphere, and other features of the Earth reflect 31% of the incident radiation. Taking this into account reduces T_e to 255 K.

Theoretically, if the planet's surface cooled by radiation alone, then the greenhouse-induced surface temperature would be much warmer, about 350 K (77 °C). Atmospheric motion (convective towers carrying latent and sensible heat upwards and large scale circulation carrying it both upwards and polewards) circumvent much of the greenhouse effect and significantly increase the "escape" of energy to space, leaving Earth's surface more than 60 °C cooler than a static atmosphere would do.

Additionally, greenhouse gases are only able to absorb radiation in very specific electromagnetic frequencies and Earth does not radiate limitless amounts of energy in the appropriate bandwidths. This means there is 'competition' for available energy and significant greenhouse potential is unrealized (carbon dioxide could absorb more than 3 times the energy it currently does in the atmosphere were it not for competition from clouds and water vapor, clouds alone could absorb 50% of available energy but manage to capture just 14% and so on...).

So, despite there being far more greenhouse gas in the atmosphere than required to achieve the current greenhouse effect, something which has been true since before humans discovered fire, evapo-transpiration and thermals transport heat higher in the atmosphere where radiation to space is increased. This is why Earth remains about 15 °C (288 K) rather than about 77 °C (350 K).

Wait a minute! Those aren't the numbers I learned!

Ah! Someone who remembers their science classes eh? Well, you got us. Reference works frequently list the planet's mean surface temperature as 16 °C (289 K, 61 °F); sometimes 15 °C (288 K, 59 °F) is mentioned and yes, these are about the expected temperatures by calculation -- in the 1960s and 1970s numbers as high as 65 °F (18 °C, 291 K) were popular but we haven't seen those for some time. Here we run into a little bit of a problem, however -- taking the Earth's temperature is no trivial task. In fact, even defining precisely what we mean by the absolute surface air temperature is challenging. Current global temperature anomalies (the amount of warming or cooling reported) are estimated against an expected average of 14 °C (287 K, 57 °F) -- the guess-timated mean temperature over the period 1961-1990.

Sidebar:

One of the quirks of climate science is that climate models are frequently 'tuned' to reproduce the expected mean temperature of 287 K or 14 °C and, somewhat bizarrely, 14 °C is thought to be the correct figure because 'the most trusted models produce it'. While the average of model representations of global climate suggests Earth's mean temperature is about 14 °C (287 K), the 16 most trusted and 'stable' models tested in the Coupled Model Intercomparison Project (CMIP) (see original .pdf) are not well able to reproduce this result.

This graphic represents the unforced control runs for the "ensemble" (IPCC-speak for "haven't got a clue if any of these actually represent reality -- throw 'em all together and say the errors average out"). The range starts out guessing mean Earth surface temperature as anything from 11.5 to 16.5 °C (roughly 285-290 K) and ends -- without messing with carbon dioxide levels or anything else -- with the guesses even further apart. The absolute mean surface air temperature of the Earth is actually not known and there is no specification of exactly what we are trying to measure or how to go about doing so. No one knows what Earth's optimal temperature would be or how it could be knowingly and predictably adjusted even if an optimum could be agreed.

[salbers]

Well it's interesting to remind ourselves how the effects of convection and such place the atmosphere at a radiative disequilibrium. Getting back to CO2 though, we can recall the higher levels during the dinosaur era when is was quite a bit warmer. I have a hard time believing this was just a coincidence.

Also it's true that absorption windows of various gases add some complexity to the radiative calculations. It seems though the changes should be fairly linear in nature over the relatively small increases of a few degrees we're talking about. CO2 can be seen in the spectrum of the atmosphere, so we know it does have an effect. Your article above says little specifically about CO2 radiative forcing calculations (or their effect on temperature) being in error. Just because models have to be tuned to get the baseline balances right doesn't really matter much in my opinion about the magnitudes of the basic forcing mechanisms.

[BethesdaWX]

Well it's interesting to discuss the effects of convection and such to place the atmosphere at a radiative disequlibrium. Getting back to CO2 though, we can recall the higher levels during the dinosaur era when is was quite a bit warmer. I have a hard time believing this was just a coincidence.

Exacty. You can't peg CO2 as the cause even with solar 30% weaker.....what would cause CO2 levels to rise so high? Answer, they were driven. As the GHE would be, Solar Had a much higher Impact on our planet, as the relationship is in a different state now.

[BethesdaWX]

Look, the whole point behind my argument, is the fact that we are by no means sure of the actual impact of CO2 increae on the system. Our different thoughts on the relationship is what mkes us Skeptics & believers.

I agree, I do not want to risk our planet.... but there is little we can do if CO2 warming is drastic as what the IPCC states it will be. We'll know soon enough.

Have a good evening

[salbers]

Exacty. You can't peg CO2 as the cause even with solar 30% weaker.....what would cause CO2 levels to rise so high? Answer, they were driven. As the GHE would be, Solar Had a much higher Impact on our planet, as the relationship is in a different state now.

It was also quite warm 100 million or so years ago when the sun was only slightly weaker. CO2 levels weren't driven by ocean warming/outgassing as there's not enough in the ocean to do this. It was probably increased by volcanoes or the lack of geological sequestering, and then drove the temperatures.

[salbers]

Look, the whole point behind my argument, is the fact that we are by no means sure of the actual impact of CO2 increae on the system. Our different thoughts on the relationship is what mkes us Skeptics & believers.

I agree, I do not want to risk our planet.... but there is little we can do if CO2 warming is drastic as what the IPCC states it will be. We'll know soon enough.

Have a good evening

Well it's hard to be a skeptic and a defeatist at the same time, though somehow you are managing to do this. Funny I'm saying that when I don't usually try to label people

Catch you later.

[BethesdaWX]

It was also quite warm 100 million or so years ago when the sun was only slightly weaker. CO2 levels weren't driven by ocean warming/outgassing as there's not enough in the ocean to do this. It was probably increased by volcanoes or the lack of geological sequestering, and then drove the temperatures.

Ok, I'm heading out for a sunday night fling, 1 more post from me. (not much time to go in depth though )

Ocenas hold more than 50x the amount of CO2 that the atmosphere does.

CO2 can't create 6-10C warming either, it was, again, most likely driven by a combination of very high solar activity (maybe a few solar firehoses towards earth as well?), not mentioning that te one supercontinent Pangea built up alot of heat, where most of our proxies are based on. Either way, CO2 PPM was near 5000. Altering the base of our global temperature also can lead to a more favorable environment for CO2 to occupy.

[beneficii]

Ocenas hold more than 50x the amount of CO2 that the atmosphere does.

What does this have to do with radiative forcing? Nothing in your post explains it.

CO2 can't create 6-10C warming either, it was, again, most likely driven by a combination of very high solar activity (maybe a few solar firehoses towards earth as well?), not mentioning that te one supercontinent Pangea built up alot of heat, where most of our proxies are based on. Either way, CO2 PPM was near 5000. Altering the base of our global temperature also can lead to a more favorable environment for CO2 to occupy.

Salbers was talking about water vapor, and possibly methane and albedo, feedbacks leading to 3 °C or more warming, being driven by a doubling of CO2.

[BethesdaWX]

What does this have to do with radiative forcing? Nothing in your post explains it.

Salbers was talking about water vapor, and possibly methane and albedo, feedbacks leading to 3 °C or more warming, being driven by a doubling of CO2.

You missed the base point.

The CO2 rise then was obviously driven........by temperature. The rise in CO2 level was most likely driven by an Increase in Solar Activity.....due to the Earths position in its multi-millenia orbital cycle, & the fact that the sun was still maybe 5% weaker 100 million years ago, as earth is very sensitive to that............The CO2 itself may have had very little impact.....even being over 5000ppm.

Now, to stray away from the "5000ppm" way back when.... our current CO2 is at 390ppm, and how much are we responsible for this?

Humans can only claim responsibility, if that's the word, for abut 3.4% of carbon dioxide emitted to the atmosphere annually, the rest of it is all natural (you can see the IPCC representation of the natural carbon cycle and human perturbation here or a simple schematic from Woods Hole here).

Half our estimated emissions fail to accumulate in the atmosphere, "disappearing" into sinks as yet undetermined. Humans' total accumulated carbon contribution could account for perhaps a quarter of the total non-water greenhouse gases (that is, accounting for all the increase since the Industrial Revolution regardless of source and irrespective of whether warming from any cause might result in an increase in natural emission to atmosphere -- we're simply claiming the lot as anthropogenic or human-caused here). Assuming that water vapor accounts for about 70% and clouds (mostly water droplets) accounts for another 20%, thus water in it's various forms is 90% of the total greenhouse effect, leaving 10% for non-water greenhouse effect (we know we cited 95% above -- see "important distinction"). Of this remaining 10%, mainly atmospheric carbon, humans might be responsible for 25% of the total accumulated atmospheric carbon, meaning 0.25 x 0.1 = 0.025 x 100 = 2.5% of the total greenhouse effect.

In reailty, you have to consider the facts, the two time periods cannot be related due to a variety of factors... human enhanced CO2 warming is minimal at best.

http://www.junkscience.com/Greenhouse/