Psychoserenity wrote:Feck wrote:Seems to me Mistermack is looking for a crocoduck ,or it's climate change equivalent .
I can't be bothered here, he's ignoring everything anyway.
Thanks for laying out that he has it backwards with his ice core proofs of the CO2 following temperature, I didn't have it in me to break out the spoon for feeding time. The closeness of correlation should be cause for concern, if you're a layman and that's the prima facie case you're faced with.beige wrote: I don't know, I feel like I'm banging my head into a brick wall. Would you like further explanation of the feedback mechanisms, what exactly aren't you accepting/agreeing with here? I've tried to explain things as best I can, but I have no formal educative training, nor any formal climatology training - I'm just trying to repackage the information that I've come across in such a fashion that might help you understand.
beige wrote:*sigh*mistermack wrote:I would have to disagree with you there. They use the word covariance when they could easily in three or four words have indicated which was leading and which was following. It's absolutely crucial, as they veryt well know. And it's deliberately misleading because they go on to claim that it shows CO2 is driving temperature rises, when if they had said which was actually leading, would have made that claim look ridiculous.
It's a deliberately false impression being left, and a false claim being made.
And you see that all the time in climate science. Maybe they just want people to log in and pay to read the full article, but I think it's sneakier than that.
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Okay, I'd like to make this clear. It's NOT crucial at all.
A) That's just an abstract from a paper, thus a summary. Lag times might be mentioned in the paper itself, but they aren't in the abstract because:
B) The abstract indicates what's important about this particular study, not details from it.
C) That in the past C02 lagged temperature is already accepted, and it's NOT A PROBLEM and it's nothing new, so there is no point in putting it in the abstract.
D) It's not a problem, because past warming wasn't driven by C02. C02 was INVOLVED, and compounded warming, but it wasn't driving it. Hence - it doesn't MATTER that it lags, in fact that is exactly what you'd EXPECT.
Now, if they were claiming that C02 was the driving force that caused past warming then YES it would look ridiculous that C02 lagged, but no one is suggesting that.
Why current warming is different is because it IS being forced by a sudden increase in C02 levels, thus making increased C02 the initial catalyst, not something else such as increased solar irradiance. If you're pumping hundreds of millions of tons of C02 into the atmosphere then you don't get the lag times. Why not? Because you're providing the extra C02 yourself, you don't need to wait for the positive feedback loops from differing ocean solubility to add more C02 over long periods of time after temperature changes. because we humans are cutting that corner out. We're effectively speeding up the positive feedback artificially.
I don't know, I feel like I'm banging my head into a brick wall. Would you like further explanation of the feedback mechanisms, what exactly aren't you accepting/agreeing with here? I've tried to explain things as best I can, but I have no formal educative training, nor any formal climatology training - I'm just trying to repackage the information that I've come across in such a fashion that might help you understand.
http://www.newscientist.com/article/dn1 ... atter.htmlSo what's going on? It is true that human emissions of CO2 are small compared with natural sources. But the fact that CO2 levels have remained steady until very recently shows that natural emissions are usually balanced by natural absorptions. Now slightly more CO2 must be entering the atmosphere than is being soaked up by carbon "sinks".
I do apologise, it must be tiring when people hold different opinions to yours.beige wrote: *sigh*
Yes it's a summary. A dishonest summary. To use the word "covariance" and then claim that it shows CO2 driving warming is just about as dishonest a summary as I've ever seen.beige wrote: A) That's just an abstract from a paper, thus a summary. Lag times might be mentioned in the paper itself, but they aren't in the abstract because:
B) The abstract indicates what's important about this particular study, not details from it.
Good, very good. You're nearly there. Because this is exactly the OPPOSITE of what the famous models predict.beige wrote: C02 was INVOLVED, and compounded warming, but it wasn't driving it. Hence - it doesn't MATTER that it lags, in fact that is exactly what you'd EXPECT.
Look again at the ice-core graphs. It's not different. There have been huge rises in CO2 in the past. Where is the immediate warming? Nowhere.beige wrote: Why current warming is different is because it IS being forced by a sudden increase in C02 levels, thus making increased C02 the initial catalyst, not something else such as increased solar irradiance.
The mechanism of a rise in temp. following a rise in CO2 within fifty years. That's the mechanism I would like to see illustrated.beige wrote: I don't know, I feel like I'm banging my head into a brick wall. Would you like further explanation of the feedback mechanisms, what exactly aren't you accepting/agreeing with here?
Of course I don't deny the greenhouse effect. I'm denying the claim that the sort of levels of CO2 that we have at the moment will make the temperatures rise significantly.Tero wrote:So you are now denying the greenhouse effect? Or you are still stuck on the chicken and egg?
You're still not getting what I'm saying. I entirely accept the rise in CO2, and the huge amounts we are putting into the air. That's all undeniable fact. You seem to be under the impression that more CO2 = more warming. That's what I dispute.Tero wrote:All the evidence was presented here, my best was the isotope effect (proves coal as a major source). You will only get more data by subscribing to the journals. So what exactly are you asking for? Nobody here has more data for you.
I suppose that boils down to you saying that correlation doesn't equal causation? You accept there is a link, but you're not convinced the link is shows relation. I'll try and explain again, how it's not really dishonest, because the historic record and the way C02 influenced climate in the past is consistent with those lag times.mistermack wrote:Yes it's a summary. A dishonest summary. To use the word "covariance" and then claim that it shows CO2 driving warming is just about as dishonest a summary as I've ever seen.
It's like summing up the 100m olympic final by saying that the speed of Usain Bolt and Richard Thomson covaried, and Richard Thomson was clearly a better runner than Bolt. Then you buy the article, and they have to let it slip that Bolt finished first.
The fact that increased C02 levels resulted in warming IS shown in the ice cores, I'll give explaining it another shot. Also you seem to be confusing predictions for the future, and recent past with records of the far past, both of which are dealing with the same issue, and the same variables, but the situation is effectively reversed between then and now in terms of how the climate change is actually being initiated, and that makes all the difference.Good, very good. You're nearly there. Because this is exactly the OPPOSITE of what the famous models predict.
The models predict a rise in CO2 HAS TO result in warming. This effect is completely missing in the ice-core evidence.
So you seem to be saying that the models don't have to have worked over history, but they are sure to be correct today.
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Change in temperature > Increase in C02 > more C02 increases temperature further > higher temperature releases yet more C02. Code: Select all
temperature lowers > because the temperature lowers, more C02 can be absorbed > less C02 in the atmosphere lowers temperatures further > further decreases in temperature then leads to even greater C02 absorption.Again, the models generally describe the current warming trend, in the past time was needed for the C02 concentration to change, and as such the temperature variations drag out over very long periods of time. The current warming corresponds with a sudden influx of C02 into that cycle, and thus we predict (and see) an uncharacteristic warming trend accompanied with that during current warming.Look at those ice-core graphs. You will see some incredibly dramatic rises in CO2. ( and falls ). The models say global warming or cooling should happen almost immediatly, on the scale of those graphs.
There is nothing.
The graphs clearly and umambiguously disprove the models.
If the models were wrong over a 450,000 year period, why should we believe them now?
Already explained, it is different. Also interesting to note, is that the warming in the past had enough time to be cumulative, we can expect this sudden influx to really throw up a strong reaction through the positive feedback systems. The ice core samples show between 170 and 290 parts per million of C02 throughout that 400,000+ year period. While the current human output has fed C02 levels in the atmosphere to well over 300 parts per million currently. That extra C02 will likely have a significantly greater influence on the climate than what we're currently experiencing.Look again at the ice-core graphs. It's not different. There have been huge rises in CO2 in the past. Where is the immediate warming? Nowhere.
Okay, so as you don't accept that C02 can influence temperature I assume you don't accept the greenhouse properties of the gas as found by Tyndall? Or is the reservation you have perhaps that C02 is insignificant as greenhouse gas because of the influence of things such as water vapour which are demonstrably greater in themselves?The mechanism of a rise in temp. following a rise in CO2 within fifty years. That's the mechanism I would like to see illustrated.
I think that in this case correlation very much equals causation. The correlation from the Vostok cores is so close it's really undeniable. I'm simply pointing out that the cause has to come BEFORE the effect. I've yet to see an effect that came before a cause. Yet that is exactly what that summary suggests.beige wrote: I suppose that boils down to you saying that correlation doesn't equal causation? You accept there is a link, but you're not convinced the link is shows relation. I'll try and explain again, how it's not really dishonest, because the historic record and the way C02 influenced climate in the past is consistent with those lag times.
As far as I can remember, this can't account for anything of less than 100,000 year frequency. If you look at the vostok graphs, the correlation is much closer than that. It's fair enough provisionally putting 100,000 year events down to that, but nothing quicker than that. Have another look at the graphs, the ups and downs match over much shorter periods. The four big spikes you could assign to the Milankovitch cycles, but what's in between is also a very good match.beige wrote: In the past, we can compare the changes from warming to cooling in the temperature record pretty closely to the Milankovitch cycles.
No, that doesn't tally with the huge variation shown in the Vostok cores.beige wrote: Now, given that usually the natural C02 output is fairly constant in respect to the natural C02 uptake, the C02 doesn't under normal circumstances affect things all that much - it's effect is balanced.
I don't think so. If you read the temp graph, going from right to left, you get the depths of the ice-age, then a huge spike, then a huge fall, and then up and down, gradually falling. And that's repeated four times, so it's no fluke. Temperature rises are sudden, but falls are more gradual. So it looks like the rises are forced, and the falls are just a gradual return to a norm.beige wrote: In the same way, to bring the temperatures back down, you need a triggering event, such as reduced solar irradiance from the low point in the milankovitch cycle.
Of course I accept the greenhouse effect keeps the earth warmer than it would otherwise be. But I don't accept that CO2 has the ability to keep it warmer than current levels, especially at the levels we have now. Try heating a poker on a flame. It's very easy to warm it from cold, even with a tiny flame. But you need a roaring flame to make it glow red. The warmer it gets, the quicker it loses heat.beige wrote: Okay, so as you don't accept that C02 can influence temperature I assume you don't accept the greenhouse properties of the gas as found by Tyndall? Or is the reservation you have perhaps that C02 is insignificant as greenhouse gas because of the influence of things such as water vapour which are demonstrably greater in themselves?
You're right - the cause does have to come before the effect, and we know what the cause and effect are, and how they interact. However, the term covariance doesn't imply any causality!mistermack wrote:I think that in this case correlation very much equals causation. The correlation from the Vostok cores is so close it's really undeniable. I'm simply pointing out that the cause has to come BEFORE the effect. I've yet to see an effect that came before a cause. Yet that is exactly what that summary suggests.
To me it's crystal clear that global warming causes higher CO2 levels, 800 years later. And it's not just me, the studies make the same conclusion, and none conclude the reverse.
Yes you're right, the Milankovtich cycles best match primarily with the major glacial changes roughly on the 100,000 year marks. However, even in the between periods, the changes from the cycle are matched pretty well to the ice core graphs. I'm not saying that changes in the orbit are to blame for every warming or cooling trend in the past, but as I said before, it's one of the big factors, that affects the major temperature changes. There are a multitude of things that can affect the climate, and any one of them can be used to fill in the few gaps that aren't explained by things such as the milankovitch cycles. Even across those past records, we're talking about only a couple of degrees warming on average over a periods of tens of thousands of years - that alone should indicate how much different the current trend is.As far as I can remember, this can't account for anything of less than 100,000 year frequency. If you look at the vostok graphs, the correlation is much closer than that. It's fair enough provisionally putting 100,000 year events down to that, but nothing quicker than that. Have another look at the graphs, the ups and downs match over much shorter periods. The four big spikes you could assign to the Milankovitch cycles, but what's in between is also a very good match.
Note that the lower graph has been moved about 800 years to the right, making an excellent match.
http://en.wikipedia.org/wiki/File:Vostok_Petit_data.svg
The new ice cores suggested that a powerful feedback amplified the changes in sunlight. The crucial fact was that a slight warming would cause the level of greenhouse gases to rise slightly. For one thing, warmer oceans would evaporate out more gas. For another, as the vast Arctic tundras warmed up, the bogs would emit more CO2 and methane. The greenhouse effect of these gases would raise the temperature a little more, which would cause more emission of gases, which would... and so forth, hauling the planet step by step into a warm period. Many thousands of years later, the process would reverse when the sunlight falling in key latitudes weakened. Bogs and oceans would absorb greenhouse gases, ice would build up, and the planet would slide back into an ice age. This finally explained how tiny shifts in the Earth's orbit could set the timing of the enormous swings of glacial cycles.
Perhaps that was badly worded, but I was trying to use that to explain how the feedback mechanisms work. If uptake and output are constant, then they on their own wont change temperature, (well, higher levels will cause higher temperatures, but if the amount of C02 in the atmosphere is constant, then the amount of warming it produces will also remain constant) because things stay in equilibrium. However, in practice, there are other factors that influence climate, and as such that level of C02 over thousands of years does vary, and does compound temperature changes.No, that doesn't tally with the huge variation shown in the Vostok cores.
Not just on the four big spikes, but the significant smaller variations in between.
I can only give one explanation for such a tight correlation, with an 800 year lag, and that is warmer water taking that long to affect the CO2 reservoir in the deepest oceans. So far from being steady and balanced, it's shown to jump up and down like a jack rabbit, following climate events 800 years previously.
Not every temperature spike is strong enough, or persistent enough (things like volcanoes only being very shortlived) to set off a positive feedback loop, or to greatly affect the global average temperature over an extended period, so a lot of local or minor temperature variations are lost in the averages. Some events like particularly large volcanic eruptions might perhaps be able to influence things, but certainly not every temperature spike.If CO2 global warming is true, every temperature spike should have a corresponding one, 850 years later, caused by rising CO2.
Any warm period of sufficient magnitude to throw that natural balance off will kick off a positive feedback loop. We know how powerful they can be from research of the last glacial age. They're just natural reactions to large scale changes. They don't have a choice in when the kick in or not.I would personally have huge doubts that the Milankovitch cycles could cause such spikey behaviour in climate. The idea of it setting off a feedback mechanism could partly explain it, but it doesn't cover why that feedback mechanism doesn't constantly kick in, with every warm period.
The gun is already loaded. The ice ace does that for you, it has a massive albedo from reflecting ice, lots of greenhouse gasses trapped in the ice sheets which are quite happy to be released. The moment you add that small warming trigger to that mix you'll set things off. Start melting the ice a bit, warm the ocean a bit, release more C02.. and etc etc. Considering it takes in the thousands of years to leave an ice age, the ~800 year lags turn out to be pretty insignificant, there is more than enough time for them to get to work.Looking at the graphs, it seems to me that some pressure is gradually built up during the ice ages, which eventually "goes off" with a bang, causing a huge spike in temperatures, and extremely rapid exit from glaciation.
That cannot be CO2, as it would be clearly shown in the ice-core record, just before the huge temperature spikes.
The Milankovitch cycle could maybe act as a trigger, but something else must be loading the gun.
If the pattern is to be repeated, we seem to be right at the top of a spike at the moment, we've probably had most of the warming, and the next 25,000 years should bring constant rapid cooling. So we might be trying to find ways to prevent cooling, in the years to come.
C02 naturally produces a warming effect. So, a feedback loop that releases more C02 fuels itself more easily than a loop which has to work against that effect. On the cooling loop, you have to work against the warming effect of the C02 that's already in the atmosphere. It still only needs a small trigger, but it needs a bit longer to reach its conclusion. As such, you'd expect the cooling loop to be longer and more pronounced to a degree, but to be honest, I don't see the falls as being incredibly gradual on any of the ice core graphs. They're a bit less pronounced than the temperature increases, but not massively.I don't think so. If you read the temp graph, going from right to left, you get the depths of the ice-age, then a huge spike, then a huge fall, and then up and down, gradually falling. And that's repeated four times, so it's no fluke. Temperature rises are sudden, but falls are more gradual. So it looks like the rises are forced, and the falls are just a gradual return to a norm.
The last big spike started 20,000 years ago, and we are bumping along the top of it at the moment.
In which case, what exactly do you propose made the earth warmer than current levels in the past? It wasn't C02 on its own, but C02 contributes to the effect, and by massively increasing the amount of C02 in the atmosphere, we know from past observations that the long term effect of that increased C02 concentration will be significant net warming, both from the direct effect of C02 warming, and indirectly from that initial boost releasing more greenhouse gasses (such as methane) and triggering other warming loops. The worrying thing, and it should be worrying - is that we're only at the moment seeing that initial direct warming effect. The feedback loops will take time to come around for the current warming, and that's when things will start to get really hairy, because by the time those loops come into play, there's not really any way to influence them. (You analogy doesn't work, because this poker is effectively insulated and then held next to the flame after being removed, radiating more heat doesn't make a difference if that heat cannot escape. It's like hitting a tennis ball into a wire fence, sometimes the ball might squeeze through the fence, but most of the time it'll come straight back at you.)Of course I accept the greenhouse effect keeps the earth warmer than it would otherwise be. But I don't accept that CO2 has the ability to keep it warmer than current levels, especially at the levels we have now. Try heating a poker on a flame. It's very easy to warm it from cold, even with a tiny flame. But you need a roaring flame to make it glow red. The warmer it gets, the quicker it loses heat.
In like manner, it's easy for greenhouse gases to keep the chill out, but harder to get the earth really hot. Warmer surfaces radiate more heat.
I don't believe CO2 has anywhere near enough power to counteract that effect.
Positive feedback loops are one of the most powerful things in science, if only because they can keep going through until one of the stages of the loop becomes saturated. For example, in the loop I use in my main example, if the amount of C02 that can be output by the ocean warming begins to slow down, then the absorption can one again overtake the output and will start reversing the activity of the previous loop. The climate sensitivity from such feedback loops has been discussed (link, link) - and found to be significant.I also think that everyone is making far too much from feedback loops. You surely need direct observations of data proving this, before you can use it. Otherwise you're piling one speculation on top of another.
Thanks for the interesting discussion, I admit that finding relevant evidence and research data (with sufficient explanation) isn't an easy task at all - especially if you're searching for a very specific answer to a specific question. Users browsing this forum: No registered users and 4 guests
