Evidence for CO2 causing global warming?

[owtth]

And Beige, you only have to read up on the evidence. The ONLY link established between CO2 and warming, is that CO2 levels rise consistently, 800 years approx after a warm period. This is put down to warmer surface water in the oceans being circulated down to the depths, reducing eventually the ability of the ocean to store so much CO2.
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As far as I know, that applies to Ice Ages, ice ages are a different kettle of fish, because the warming after those is triggered by orbital shifts, not carbon dioxide. It's a different mechanism entirely to the current warming.

No, that link holds good over a huge swathe of time, including warm and cold periods. Look it up.
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People (myself included) are presenting you with opinions and facts from which you conclude the exact opposite of what is apparent, it is incredibly frustrating and nonsensical.

[Robert_S]

I still don't have enough proof that Tesco is not a hoax perpetrated by the whole of the UK (is Ireland in on it too?) on us innocent and trusting Merkins.

[Animavore]

I still don't have enough proof that Tesco is not a hoax perpetrated by the whole of the UK (is Ireland in on it too?) on us innocent and trusting Merkins.

We were just following orders. It's all England.

[mistermack]

Beige, even in articles pushing CO2 caused global warming, the 800 year lag is accepted. And it's there in the original hockey stick graph. They have since worked on that, to try to get it out, or at least, less pronounced.
The cause you can argue about. It doesn't follow the orbit wobble faithfully, like the ice ages have been shown to.
But one fact is inescapable. If a rise in CO2 causes a rise in temp, then there can be NO LAG. The CO2 should show a clear 50 year LEAD. Not any kind of lag, except in response to very exceptional climate events.
The trend should be there in ice cores, and cores from lake bottoms. It should be crystal clear. But the link doesn't exist in any cores.
I have read plenty about global warming, and I always look for EVIDENCE, not opinions. I still can't find it. If anyone can link to evidence of temp FOLLOWING CO2 changes, especially within 50 YEARS! I would be very interested.
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[beige]

Beige, even in articles pushing CO2 caused global warming, the 800 year lag is accepted. And it's there in the original hockey stick graph. They have since worked on that, to try to get it out, or at least, less pronounced.
The cause you can argue about. It doesn't follow the orbit wobble faithfully, like the ice ages have been shown to.
But one fact is inescapable. If a rise in CO2 causes a rise in temp, then there can be NO LAG. The CO2 should show a clear 50 year LEAD. Not any kind of lag, except in response to very exceptional climate events.
The trend should be there in ice cores, and cores from lake bottoms. It should be crystal clear. But the link doesn't exist in any cores.
I have read plenty about global warming, and I always look for EVIDENCE, not opinions. I still can't find it. If anyone can link to evidence of temp FOLLOWING CO2 changes, especially within 50 YEARS! I would be very interested.

Yeah, I have nothing against the lag itself, it's actually consistent with what we know.

When the orbit shifts in such a way that more energy from the sun hits the earth, we get warming. This warming reduces the solubility of C02 in the oceans, over time this means that C02 builds up in the atmosphere following a higher solar output. The increased C02 levels then further compound the problem by causing positive feedback, increasing temperature further and causing less and less C02 to be retained, and letting more into the atmosphere over a longer period of time. Eventually, when the solar output falls again the oceans are able to take up more C02, so then following a cool period the C02 later falls, and in the same way as before, the positive feedback aids further cooling. It's not just C02 that affects that climate, there are a number of factors, and depending on which factor is "forcing" the climate, we see different things happening - in the case of these lag times, C02 is not forcing, it's solar output.

This is the normal cycle, the rises and falls in solar energy reaching the earth ordinarily guide the climate more than C02. That's fine, we accept that and there isn't much we can do. However, at this moment in time, it's not changes in solar output affecting the climate, we're outputting enough C02 in a very short space of time (geologically) that our influence is outweighing the solar influence. And that's the worry, because we don't really know how that will affect us, eventually the planet will stabilise itself and recover, but that takes a very long time - and the question is if humanity can adapt to the potential consequences of this. I hope that's clear enough.

[mistermack]

Feck, I have read about the methane component. But this is something that is going on worldwide every day of the year. Methane is always being produced, but there is no evidence it has ever had an effect on climate.
There was a movement recently to point to frozen methane at the bottom of the sea as a deadly hazard, that cause catastrophic climate change if the world warmed a few degrees.
Less well publicised is that the same people did studies in greater depth, and now conclude that it won't happen, and probably never happened.
You only get the scare stories in the media. Anything pointing the other way, you have to find for yourself.

Think of this. The world in the past was LOCKED into a severe ice age, with much lower CO2 levels, much higher reflection from the polar ice, and all the methane locked up by the cold, and little being produced

And from all that, the earth warmed. No manmade CO2 involved.
It went from ice age to warm age.
Compared to that, our 0.5 degree warming is zilch.
All that happened without us, how can we possibly make such confident conclusions from a half of one degree?
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[mistermack]

Beige, even in articles pushing CO2 caused global warming, the 800 year lag is accepted. And it's there in the original hockey stick graph. They have since worked on that, to try to get it out, or at least, less pronounced.
The cause you can argue about. It doesn't follow the orbit wobble faithfully, like the ice ages have been shown to.
But one fact is inescapable. If a rise in CO2 causes a rise in temp, then there can be NO LAG. The CO2 should show a clear 50 year LEAD. Not any kind of lag, except in response to very exceptional climate events.
The trend should be there in ice cores, and cores from lake bottoms. It should be crystal clear. But the link doesn't exist in any cores.
I have read plenty about global warming, and I always look for EVIDENCE, not opinions. I still can't find it. If anyone can link to evidence of temp FOLLOWING CO2 changes, especially within 50 YEARS! I would be very interested.

Yeah, I have nothing against the lag itself, it's actually consistent with what we know.

When the orbit shifts in such a way that more energy from the sun hits the earth, we get warming. This warming reduces the solubility of C02 in the oceans, over time this means that C02 builds up in the atmosphere following a higher solar output. The increased C02 levels then further compound the problem by causing positive feedback, increasing temperature further and causing less and less C02 to be retained, and letting more into the atmosphere over a longer period of time. Eventually, when the solar output falls again the oceans are able to take up more C02, so then following a cool period the C02 later falls, and in the same way as before, the positive feedback aids further cooling. It's not just C02 that affects that climate, there are a number of factors, and depending on which factor is "forcing" the climate, we see different things happening - in the case of these lag times, C02 is not forcing, it's solar output.

This is the normal cycle, the rises and falls in solar energy reaching the earth ordinarily guide the climate more than C02. That's fine, we accept that and there isn't much we can do. However, at this moment in time, it's not changes in solar output affecting the climate, we're outputting enough C02 in a very short space of time (geologically) that our influence is outweighing the solar influence. And that's the worry, because we don't really know how that will affect us, eventually the planet will stabilise itself and recover, but that takes a very long time - and the question is if humanity can adapt to the potential consequences of this. I hope that's clear enough.

Yes, it's clear. I react to being told it's all established and beyond argument, when it's anything but. My own position is "we don't know". But I still ARGUE that we SHOULD know, if what we are being told is true.
If global temperatures react that strongly to CO2 levels, it should be CLEARLY written in the ice cores etc. And it would be practically impossible to come out of an ice age.
If you look what happens in an ice age, with the huge areas of reflective ice, lower CO2 and less methane being produced, how could the world possibly come out of it with just a slight increase in solar radiation? Surely what we got extra due to the wobble, we would be losing from reflection by the ice?
There must be much more going on than we know.
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[Feck]

Yet again you are comparing climate change due to natural phenomena over thousands of years with a sudden rise in both global temp and man made Co2 We have rapid climate change that is not in response to these slow natural cycles . No amount of you saying 'it's just a model ' will change the fact that as more data is collected the model seems to be predicting things better and better . I do not know what you would accept as proof I suspect that such conclusive proof as you would accept may not be available But the climate change skeptics are running out of ideas to explain the increasing amount of data that we are gathering that supports the theory .

[beige]

Yes, it's clear. I react to being told it's all established and beyond argument, when it's anything but. My own position is "we don't know". But I still ARGUE that we SHOULD know, if what we are being told is true.
If global temperatures react that strongly to CO2 levels, it should be CLEARLY written in the ice cores etc.

It is

And it would be practically impossible to come out of an ice age.
If you look what happens in an ice age, with the huge areas of reflective ice, lower CO2 and less methane being produced, how could the world possibly come out of it with just a slight increase in solar radiation? Surely what we got extra due to the wobble, we would be losing from reflection by the ice?
There must be much more going on than we know.

There are numerous ways the climate can be affected, all it needs is a couple of short bursts of activity one way or another to kickstart the feedback processes that flip the northern hemisphere from ball of ice, to sunny paradise. Over the glacial erosion reduces available landmass, and thus area for reflection, particular times of high volcanic activity.

As for it not being significant, I disagree. It only takes a couple of degrees to make some really big changes to the way we have to live our lives, and being half a degree on our way is a mighty big step. I do feel the actual mechanism itself, and whether its taking place is well beyond discussion, it's happening whether we like it or not. Still up for debate is more how it will actually affect us, which is somewhat less certain.

[mistermack]

Yet again you are comparing climate change due to natural phenomena over thousands of years with a sudden rise in both global temp and man made Co2 We have rapid climate change that is not in response to these slow natural cycles . No amount of you saying 'it's just a model ' will change the fact that as more data is collected the model seems to be predicting things better and better . I do not know what you would accept as proof I suspect that such conclusive proof as you would accept may not be available But the climate change skeptics are running out of ideas to explain the increasing amount of data that we are gathering that supports the theory .

Yes but half the rise took place before there was any substantial rise in CO2.
People seem to be ignoring that. So you have a half of one degree, clearly with no CO2 cause. Then there was a drop in temperature, when I was born. Then a rise from the mid sixties. None of this followed CO2 levels.
We are concluding everything from a forty year period, which is nothing, in climate terms. If climate followed CO2 levels within forty years, we would have the evidence.
I'm not just saying, "you can't prove it", I'm saying that the evidence OUGHT to be crystal clear, and giving my reasoning.

It's estimated that CO2 levels have been more than THREE TIMES higher in the past than todays levels. How could the world possibly cool, from that situation, if all the scare stories are true?
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[mistermack]

That link you gave, beige, only mentions covariation. That is established, and nobody is disputing that.
What they don't say, because it didn't happen, is CO2 levels LEADING temperatures.
That's the whole point. They say covariation, I say 800 year lag. They mean the same thing, but they are clearly trying to give a false impression, and why on earth would they do that?.
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[owtth]

Mistermack, do you realise that the Industrial Revolution has only happened once? With such a poor sample nothing can be crystal clear especially in relation to such a complex sysytem, all we can rely on is probability, nobody is claiming infallibility in terms of gauging effect just that there is an effect and it is clearly detrimental. No one will say "well it's 40% man's fault but the Sun has to take a share of the blame" it is happening and we are adding to it.

[mistermack]

Mistermack, do you realise that the Industrial Revolution has only happened once? With such a poor sample nothing can be crystal clear especially in relation to such a complex sysytem, all we can rely on is probability, nobody is claiming infallibility in terms of gauging effect just that there is an effect and it is clearly detrimental. No one will say "well it's 40% man's fault but the Sun has to take a share of the blame" it is happening and we are adding to it.

You're a lot younger than me. I was born in 1950, and the climate was getting colder. We had some very cold winters, and the climateologists were speculating that we were heading for the next ice-age, and it was very convincing at the time.
The industrial revolution had a tiny effect, until the car became widespread.
Carbon emissions were negligible till very recently, yet we warmed half a degree.
It's just not established by the evidence.
Going back to my original post, why ISN'T THERE a UN global warming website, with this so-called overwhelming evidence stacked up? If it's so important, why must people search for it, hidden away in papers that you have to pay for to read?
I'm saying the evidence just isn't there. That's why they have never put it all in one place, without the bullshit.
If I worked for the UN, and believed in the evidence, the first thing I would do would be to get it out there, on it's own website, for all the world to see.
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[beige]

We had some very cold winters, and the climateologists were speculating that we were heading for the next ice-age, and it was very convincing at the time.

The videos by greenman on youtube cover that and have been posted in this thread already, basically it was simply media fearmongering again (which I agree is terrible). The second thing to note, is that at this point in the 1950s, the link between human C02 output and changes in climate were starting to be looked at in more detail, and it wasn't until later in the 70s that enough evidence had built up that the idea began to gain some serious momentum, the thing is that although certain areas may experience colder or warmer periods that are unusual, this is usually due to other local factors. In order to determine the global climate change, readings from all over the world are taken and statistically analysed to give an accurate global average temperature, and it's that which is being discussed. It's also important that the vast majority of papers even this early on were suggesting a general warming trend, not a cooling one.

The industrial revolution had a tiny effect, until the car became widespread.
Carbon emissions were negligible till very recently, yet we warmed half a degree.
It's just not established by the evidence.

The amount of C02 in the atmosphere was a pretty steady value around 280 parts per million over the last 1000 years. From around 1800 onwards, we've seen a pretty steady but sharp rise in the concentration of C02 in the atmosphere which is now approaching 400 parts per million. I'd hardly say the industrial revolution had a negligible effect, but it's true that the rate of emission has increased over time.

Going back to my original post, why ISN'T THERE a UN global warming website, with this so-called overwhelming evidence stacked up? If it's so important, why must people search for it, hidden away in papers that you have to pay for to read?
I'm saying the evidence just isn't there. That's why they have never put it all in one place, without the bullshit.
If I worked for the UN, and believed in the evidence, the first thing I would do would be to get it out there, on it's own website, for all the world to see.
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This is why the IPCC was set up, to collect and collate available data from scientific experiments and observation in such a format that government bodies could make use of it and have a definitive basis on which to determine appropriate legislation. They do produce regular reports which for the most part do a good job of summing up the most recent evidence on the climate change issue straight from the scientific literature.

There are also plenty of websites and resources available which put the evidence in terms that the general public can get their heads around, most provide a nice chunk of references to support what they're saying, and if all else fails - you can always ask other people too and see if they can perhaps explain it better.

As for covariance, it's just a statistical term, I don't think it's anything particularly dishonest, it's a word that fits the relationship between C02 and temperature. It was used there because it describes what the data is telling us, no more, no less. That paper wasn't concerning itself with how carbon dioxide affects temperature, it was dealing with what the historical record was showing us. As such, there was no need to indicate what followed what. How and why the lag time is there is covered in other papers, and there's no need to rehash what's already been said when you've got something new to add. It's the kind of language I'd expect when reading scientific literature.

[PsychoSerenity]

Going back to my original post, why ISN'T THERE a UN global warming website, with this so-called overwhelming evidence stacked up? If it's so important, why must people search for it, hidden away in papers that you have to pay for to read?
I'm saying the evidence just isn't there. That's why they have never put it all in one place, without the bullshit.
If I worked for the UN, and believed in the evidence, the first thing I would do would be to get it out there, on it's own website, for all the world to see.
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Mistermack, what exactly do you think this evidence would look like, that it could simply be put on a website so everyone could understand it?

As I understand it, the majority of the evidence comes from thousands of studies, millions of data points, all put together into many different and highly technical climate models, which are then interpreted by climate scientists. They than get papers published in journals which are then interpreted again by other scientific bodies, science popularisers, the media, etc.

At what point do you think anyone can jump in and see exactly what's going on, without having studied it for years?