Confused about CO2? - then read this

[Chris Knight]

A reasoned discussion of why CO2 increase is down to human emissions, and not natural.

http://www.ferdinand-engelbeen.be/klimaat/...asurements.html

What it does not attempt to do is correlate the increase in CO2 with global warming.

I found it to be a convincing essay.

[jethro]

Have you seen this Chris?

http://wattsupwiththat.wordpress.com/2008/...re-driving-co2/

[Devonian]

Have you seen this Chris?

http://wattsupwiththat.wordpress.com/2008/...re-driving-co2/

This is interesting.

There are sceptics who accept the science/consensus/models/predictions but try to remain questioning and open minded (me) there are sceptics who accept the Co2 increase is anthro in origin but most of the warming not (Ferd/Hans Erren) and there are sceptics who think neither the Co2 or the warming is anthro in origin (Anthony Watts, Roy Spencer).

Personally I think Watts and Spencer are going something like this but I'd like to see why you think it's worth spending time on? For a start where is all the CO2 going if a large amount of it isn't ending up in the atmosphere? Spencer's claim that, just at the time we add giga tonnes of Co2 to the atmosphere, the amount of Co2 in the atmosphere rises but due to another entirely different cause is one whopping coincidence toooo far for me - let alone that there is other just as convincing evidence he's wrong (isotopes, and the 'bleedin' obvious' to name two).

But, jethro, you posted it, why is it worth discussing?

Edited February 4, 2008 by Devonian

[jethro]

Because it's a thread about CO2 and this gives a different perspective. If I could find Beck's paper, I'd post that too. There is still much speculation, to not look at all sides is rather odd, is it not? After all, this isn't some blog, journalist's version of AGW or indeed lay folk like us, "Roy Spencer is a principal research scientist for University of Alabama in Huntsville. In the past, he served as Senior Scientist for Climate Studies at NASA's Marshall Space Flight Center in Huntsville, Alabama. Dr. Spencer is the recipient of NASA's Medal for Exceptional Scientific Achievement."

http://en.wikipedia.org/wiki/Roy_Spencer

Engelbeen is a chemist:

http://www.ping.be/chlorophiles/en/en_clf_aut.html

[PersianPaladin]

A reasoned discussion of why CO2 increase is down to human emissions, and not natural.

http://www.ferdinand-engelbeen.be/klimaat/...asurements.html

What it does not attempt to do is correlate the increase in CO2 with global warming.

I found it to be a convincing essay.

Erm...its pretty obvious that an increase in CO2 = increase in warming.

You only need to look at planets with CO2 rich atmospheres to see the exarcebating and insulating affect it has.

Edited February 4, 2008 by PersianPaladin

[Devonian]

Because it's a thread about CO2 and this gives a different perspective. If I could find Beck's paper, I'd post that too. There is still much speculation, to not look at all sides is rather odd, is it not?....

But, don't we look at things and then come to conclusion if the evidence is good? Isn't that what science is, building on the shoulders of giants and all that, and isn't that what education passes on? I've looked at these ideas and I know (and I mean it I KNOW) that the extra atmospheric CO2 is, essentially, anthopogenic. I've learnt that from the experts and what they write, from the science, from the evidence. To question, or rather to keep questioning something we understand - I'm sorry I just don't see why? We know how rain is formed, do we have to keep going back over old ideas about that (that the gods cause it, or it's some goddesses tears or something) over and over and over and over and over again like we do across the net wrt atmospheric CO2 increase? What's the point of learning if we're constantly stuck going over and over the basics? We'd be stuck in the 1500's if we always did that!

I say this. These posts denying the increase in CO2 is anthropogenic, these 'views', are about stopping science moving, about obfuscation, about needlessly tying people up in the kind of debate I'm getting myself needlessly tied up in . The reality is, the science shows, the evidence shows, the bleedin' obvious shows, that the extra CO2 in the atmosphere is anthropogenic in origin, yet every few months someone (this time it's Roy Spencer) comes along and demands that other views be given equal time and be accepted as equally valid - sorry, not by me they wont be, because they aren't equally valid.

Now, I'm not, despite the above, closed minded (just in case someone is thinking of playing that card...). So, Jethro, you put the evidence forward. Do what we 'warmers' have to do all the time, explain why you think you are right, face disagreement, explain again, face disagreement, explain again, try to keep cool and keep trying. I think you've got as much chance of changing my mind as I have some here Wrt AGW, but, this time, you are the one having to do the convincing. Put forward some evidence, explain why you think you are right, to get me to change my mind. Show you understand of the science so you can show why I'm wrong.

So, over to you then

Edits for clarity

Edited February 4, 2008 by Devonian

[jethro]

But, don't we look at things and then come to conclusion if the evidence is good? Isn't that what science is, building on the shoulders of giants and all that, and isn't that what education passes on? I've looked at these ideas and I know (and I mean it I KNOW) that the extra atmospheric CO2 is, essentially, anthopogenic. I've learnt that from the experts and what they write, from the science, from the evidence. To question, or rather to keep questioning something we understand - I'm sorry I just don't see why? We know how rain is formed, do we have to keep going back over old ideas about that (that the gods cause it, or it's some goddesses tears or something) over and over and over and over and over again like we do across the net wrt atmospheric CO2 increase? What's the point of learning if we're constantly stuck going over and over the basics? We'd be stuck in the 1500's if we always did that!

I say this. These posts denying the increase in CO2 is anthropogenic, these 'views', are about stopping science moving, about obfuscation, about needlessly tying people up in the kind of debate I'm getting myself needlessly tied up in . The reality is, the science shows, the evidence shows, the bleedin' obvious shows, that the extra CO2 in the atmosphere is anthropogenic in origin, yet every few months someone (this time it's Roy Spencer) comes along and demands that other views be given equal time and be accepted as equally valid - sorry, not by me they wont be, because they aren't equally valid.

Now, I'm not, despite the above, closed minded (just in case someone is thinking of playing that card...). So, Jethro, you put the evidence forward. Do what we 'warmers' have to do all the time, explain why you think you are right, face disagreement, explain again, face disagreement, explain again, try to keep cool and keep trying. I think you've got as much chance of changing my mind as I have some here Wrt AGW, but, this time, you are the one having to do the convincing. Put forward some evidence, explain why you think you are right, to get me to change my mind. Show you understand of the science so you can show why I'm wrong.

So, over to you then

Edits for clarity

I don't have to prove anything Dev, did I say this is what I believe? Did I say the link from Engelbeen was wrong? Did I at any point say I think or believe such and such as purported by such and such is the one and only true answer? This is a CO2 thread, Chris posted a link which I found interesting, I posted another link and asked if he'd seen it. From one action and one question you have deduced a whole world of my opinion and views upon CO2 and climate change. How?

The topic of the thread is "Confused about CO2" - the whole damn world's confused about CO2. Nobody is stopping the science moving forward, if any hypothesis about AGW and the role which carbon plays is to move forward, then a good starting point would be some agreement between all these professionals.

[PersianPaladin]

I don't have to prove anything Dev, did I say this is what I believe? Did I say the link from Engelbeen was wrong? Did I at any point say I think or believe such and such as purported by such and such is the one and only true answer? This is a CO2 thread, Chris posted a link which I found interesting, I posted another link and asked if he'd seen it. From one action and one question you have deduced a whole world of my opinion and views upon CO2 and climate change. How?

The topic of the thread is "Confused about CO2" - the whole damn world's confused about CO2. Nobody is stopping the science moving forward, if any hypothesis about AGW and the role which carbon plays is to move forward, then a good starting point would be some agreement between all these professionals.

I disagree. The whole damn world is producing too much waste and crap and it needs to be cut.

[jethro]

I disagree. The whole damn world is producing too much waste and crap and it needs to be cut.

Agreed. But what on earth has this got to do with understanding CO2?

[Stratos Ferric]

Because it's a thread about CO2 and this gives a different perspective. If I could find Beck's paper, I'd post that too. There is still much speculation, to not look at all sides is rather odd, is it not? After all, this isn't some blog, journalist's version of AGW or indeed lay folk like us, "Roy Spencer is a principal research scientist for University of Alabama in Huntsville. In the past, he served as Senior Scientist for Climate Studies at NASA's Marshall Space Flight Center in Huntsville, Alabama. Dr. Spencer is the recipient of NASA's Medal for Exceptional Scientific Achievement."

http://en.wikipedia.org/wiki/Roy_Spencer

Engelbeen is a chemist:

http://www.ping.be/chlorophiles/en/en_clf_aut.html

Jethro, as we write there is an inquest going on in London to an event about which there has been probably as much speculation as there has about anything since events one morning in Dallas in the early 60s. I can understand re JFK the speculation regarding possible events and causes. I cannot understand the speculation re the Princess of Wales. The car crashed.

It is possible to speculate endlessly about pretty much anything, however, in the majority of cases the obvious cause is often THE cause. There is a lot of bluster re CO2, but as Dev very succinctly puts it, it's one hell of a consequence - if that's all that it is - to see the coincidence of man's activities and rising levels in the atmosphere.

Dev's challenge is valid. Yes there is speculation, but why do you continue to buy into it all? Presumably you also believe that the Princess of Wales was the victim of some mad plot by MI6 to prevent the birth of a muslim child into the Royal line do you? Or was it an explosion? Or was the driver a secret agent? Or was the car booby trapped? And what about the mysterious white car...

As VP said this afternoon, and I have previously mentioned over and over, we would all be well served by thinking about the point at which - if we have not already - we would be willing to give up on the search for an answer other than the one that is staring us all in the face. if you don't do that then, as we all know, there is no end to the ever more futile search for an explanation; it's really just a matter of how daft do you want to get.

Mr Al Fayed is, understandably, allowing a huge amount of personal grief, and a long standing grudge towards the British establishment, to cloud his judgement. I struggle to understand what the motive is in the case of climate change.

[Stratos Ferric]

...by the way, re the paper, the guy does start out by admitting he knows next to nothing about the subject. Yet again, the real value and insight comes from the reviews that follow.

All the paper is really saying so far as I can see is that there is a huge annual carbon exchange ongoing within which man's additional input is fairly small. Furthermore, the rate of increase in CO2 is less than man's annual input. I'm not sure there's any new news in this. In a warming world there is more vegetative growth; the net natural fibre mass should be increasing, so it seems reasonable that if CO2 causes warming, there might also, up to a point, be an increase in absorption of some of that CO2 at least. The system cannot get ahead of itself as, if this happened, temperatures would fall back, growth would slow or stop in new areas, and less would then be absorbed. Thus the whole system self regulates in an upwards direction IF this is the control process at work.

[Devonian]

I don't have to prove anything Dev, did I say this is what I believe? Did I say the link from Engelbeen was wrong? Did I at any point say I think or believe such and such as purported by such and such is the one and only true answer? This is a CO2 thread, Chris posted a link which I found interesting, I posted another link and asked if he'd seen it. From one action and one question you have deduced a whole world of my opinion and views upon CO2 and climate change. How?

Humm you posted it, but you don't agree with it? My mistake :blush: . But I would be right to think you think it of merit and worth discussing? If so why (kind of what I was getting at actually)? Why would you post the link you did rather than, say, this or this or this or this or even this?

The topic of the thread is "Confused about CO2" - the whole damn world's confused about CO2. Nobody is stopping the science moving forward, if any hypothesis about AGW and the role which carbon plays is to move forward, then a good starting point would be some agreement between all these professionals.

What confusion? There are few things more certain in this natural world, as shown by independent lines of evidence, than that humanity is (IS) responsible for the rise in concentration of atmospheric CO2. Ok, there may be people out there who wish (want even) to make people think there is confusion, but there isn't any. Seriously, it's quite clear humanity is responsible for the changes to the amount of atmospheric CO2.

Edited February 4, 2008 by Devonian

[HighPressure]

Since 2000 Co2 levels have risen 35% faster than expected 18% of that rise is attributed to the decline in our oceans ability to soak up CO2.

The British Antarctic Survey state:

"We found that nearly half of the decline in the efficiency of the ocean CO2 sink is due to the intensification of the winds in the Southern Ocean."

Dr Fraser of The British Antarctic Survey

"Higher greenhouse gas levels and depletion of the ozone layer had caused circumpolar winds around Antarctica to move closer to the poles and speed up, and storms in the Southern Ocean to intensify."

Ozone depletion continues to cause me issues with AGW and If anything my view is intensifying as real evidence is now starting to show that Ozone depletion is the main source of increased wind speed in the Southern Oceans and that increased wind speeds now has mainstream support for a major cause of Sink failure. We have yet to fully understand the effects of direct UV on the ecosystem but again evidence is growing this causes major dysfunction of at least some species of Phytoplankton.

My uneducated view (sorry profs) is that CO2 is undoubtedly a GHG responsible for a percentage (I do not know what that is) of warming. The key thing to me is what I believe the evidence points towards the simple fact that by simply reducing CO2 (on the scale possible) emissions without Ozone repair will not impact measurable on global temps as the sinks appear to be failing at a greater rate than any possible decrease in CO2. Ozone repair is something that is not a foregone conclusion we may still see records breached and indeed the hole measure its largest for Dec 8th which was the biggest ever recorded for that date.

My conclusion after reading a lot of this stuff is that we may of started a runaway effect of ocean sink failure initially due to Ozone depletion, CO2 may well enhance this effect but its removal will not stop it. Ozone repair is vital in the ability of the Oceans to soak up CO2 without it CO2 cuts are meaningless. I am driven to the overall view that CFCs are the primary cause of AGW and not CO2.

Edited February 4, 2008 by HighPressure

[Hiya]

I don't have to prove anything Dev, did I say this is what I believe? Did I say the link from Engelbeen was wrong? Did I at any point say I think or believe such and such as purported by such and such is the one and only true answer? This is a CO2 thread, Chris posted a link which I found interesting, I posted another link and asked if he'd seen it. From one action and one question you have deduced a whole world of my opinion and views upon CO2 and climate change. How?

The topic of the thread is "Confused about CO2" - the whole damn world's confused about CO2. Nobody is stopping the science moving forward, if any hypothesis about AGW and the role which carbon plays is to move forward, then a good starting point would be some agreement between all these professionals.

I'm just confused about how even apparently academic websites let alone BBc news, C4 news, most newspapers and others can't see it's CO₂, most inputs for websites have a subscript utility and a capital O yet they still get it wrong.

I had a look at the original article and it got on my nerves for said reason.

[jethro]

Jethro, as we write there is an inquest going on in London to an event about which there has been probably as much speculation as there has about anything since events one morning in Dallas in the early 60s. I can understand re JFK the speculation regarding possible events and causes. I cannot understand the speculation re the Princess of Wales. The car crashed.

It is possible to speculate endlessly about pretty much anything, however, in the majority of cases the obvious cause is often THE cause. There is a lot of bluster re CO2, but as Dev very succinctly puts it, it's one hell of a consequence - if that's all that it is - to see the coincidence of man's activities and rising levels in the atmosphere.

Dev's challenge is valid. Yes there is speculation, but why do you continue to buy into it all? Presumably you also believe that the Princess of Wales was the victim of some mad plot by MI6 to prevent the birth of a muslim child into the Royal line do you? Or was it an explosion? Or was the driver a secret agent? Or was the car booby trapped? And what about the mysterious white car...

As VP said this afternoon, and I have previously mentioned over and over, we would all be well served by thinking about the point at which - if we have not already - we would be willing to give up on the search for an answer other than the one that is staring us all in the face. if you don't do that then, as we all know, there is no end to the ever more futile search for an explanation; it's really just a matter of how daft do you want to get.

Mr Al Fayed is, understandably, allowing a huge amount of personal grief, and a long standing grudge towards the British establishment, to cloud his judgement. I struggle to understand what the motive is in the case of climate change.

All this bluster just because I had the temerity to post a link to a paper from a well respected, honoured and awarded climatologist who doesn't agree with the consensus view on AGW and CO2 in particular. If I'd posted Joe Bloggs from the Daily Express denounces AGW together with his reasons why, I'd understand.

Me thinks you all doth protest too much folks, this isn't a personal battle you know, calm down.

There is still much uncertainty over CO2 and the role it plays in AGW, not least the amount of impact it has had; if you don't understand this, think the science is a done deal, no more questions to be asked or research to be done then might I suggest your position is misguided, mis-informed and incomplete - perhaps more reading and research on your part is required before leaping on other members of this forum.

[keithtod43]

All this bluster just because I had the temerity to post a link to a paper from a well respected, honoured and awarded climatologist who doesn't agree with the consensus view on AGW and CO2 in particular. If I'd posted Joe Bloggs from the Daily Express denounces AGW together with his reasons why, I'd understand.

Me thinks you all doth protest too much folks, this isn't a personal battle you know, calm down.

There is still much uncertainty over CO2 and the role it plays in AGW, not least the amount of impact it has had; if you don't understand this, think the science is a done deal, no more questions to be asked or research to be done then might I suggest your position is misguided, mis-informed and incomplete - perhaps more reading and research on your part is required before leaping on other members of this forum.Can anyone please tell me where the proof that the rise in Co2 is causing global warming,there seems to no proof ,but we keep on being told there is.

[Devonian]

I'm just confused about how even apparently academic websites let alone BBc news, C4 news, most newspapers and others can't see it's CO₂, most inputs for websites have a subscript utility and a capital O yet they still get it wrong.

I had a look at the original article and it got on my nerves for said reason.

CO₂ :lol:

[jethro]

"Can anyone please tell me where the proof that the rise in Co2 is causing global warming,there seems to no proof ,but we keep on being told there is."

Keep searching, you won't find it. You'll find a hypothesis which works in a lab, you'll find correlation, what you won't find is proof. There's no agreement on how much CO2 will cause temperatures to rise or by how much. There's no agreement on sinks. There's no agreement on residual times. There's dispute on natural, normal levels. There's dispute on the accuracy of ice core data and historical measurements. There's dispute on ocean out gassing. There's dispute on lead/lag times. There's dispute that CO2 can only lag not lead temperature increases. In fact, all in all there's very little agreement except, in theory increased CO2 should lead to higher temperatures. It's more a case of you pays your money, you takes your choice; lots of voices from both sides all saying different things.

[Roger J Smith]

This argument gets to the heart of the problem, increased greenhouse gases certainly must be of human origin, but are they causing the observed warming, or is that a more natural phenomenon that just happens to have come along when the carbon dioxide increase made its appearance?

Why can't it be a blend of both causes, thus with a more complicated prognosis?

That's my call on it, warming produced by two different and independent causes, and thus with a complicated outlook, possible reversals muted by the ongoing warm influence of greenhouse gases.

If China's winter is anything upon which to rest one's predictions, the future could be colder than some imagine. All the pollution in the air, yet temperatures fall five degrees below normal -- what does that suggest to any reasonable observer?

[jethro]

This argument gets to the heart of the problem, increased greenhouse gases certainly must be of human origin, but are they causing the observed warming, or is that a more natural phenomenon that just happens to have come along when the carbon dioxide increase made its appearance?

Why can't it be a blend of both causes, thus with a more complicated prognosis?

That's my call on it, warming produced by two different and independent causes, and thus with a complicated outlook, possible reversals muted by the ongoing warm influence of greenhouse gases.

If China's winter is anything upon which to rest one's predictions, the future could be colder than some imagine. All the pollution in the air, yet temperatures fall five degrees below normal -- what does that suggest to any reasonable observer?

Precisely. Nothing in climatology is as simple as add a bit of this and that will happen; it's a persuasive argument but far, far too simplistic. If it were that easy, would this debate rage so loudly and for so long by so many people, professional and interested lay people alike?

[Stratos Ferric]

...

My conclusion after reading a lot of this stuff is that we may of started a runaway effect of ocean sink failure initially due to Ozone depletion, CO2 may well enhance this effect but its removal will not stop it. Ozone repair is vital in the ability of the Oceans to soak up CO2 without it CO2 cuts are meaningless. I am driven to the overall view that CFCs are the primary cause of AGW and not CO2.

HP, I suspect there's a lot in that. CO2 (together with other anthropogenic GHGs) is, most probably now leading to secondary knock-on effects. We know warmer oceans absorb less CO2, so that's one obvious knock-on. We know a warmer world has less ice, thus lowering albedo; another knock-on, which then causes more ocean warming - a double whammy.

We do all concentrate on CO2, and it might be that this had a more dominant and exclusive role at the start of warming than it does now.

Either way, the issue is anthropogenic.

"Can anyone please tell me where the proof that the rise in Co2 is causing global warming,there seems to no proof ,but we keep on being told there is."

Keep searching, you won't find it. You'll find a hypothesis which works in a lab, you'll find correlation, what you won't find is proof. There's no agreement on how much CO2 will cause temperatures to rise or by how much. There's no agreement on sinks. There's no agreement on residual times. There's dispute on natural, normal levels. There's dispute on the accuracy of ice core data and historical measurements. There's dispute on ocean out gassing. There's dispute on lead/lag times. There's dispute that CO2 can only lag not lead temperature increases. In fact, all in all there's very little agreement except, in theory increased CO2 should lead to higher temperatures. It's more a case of you pays your money, you takes your choice; lots of voices from both sides all saying different things.

Jethro, you'll be trying to tell us that CO2 doesn't warm the atmosphere at all next.

Given that no CO2 means a cold world (see other atmospheres in our solar system), and that there is NO disagreement at all, anywhere, that the reason we have a temperate biosphere is because of the CO2 that we do have, then it would be remarkable indeed, would it not, if there were just two levels of warmth. None when there's no CO2, and around 290k when there is, say, 350ppm or so.

So, are you suggesting that additional CO2 does NOT lead to warming of the atmosphere.

...

Why can't it be a blend of both causes, thus with a more complicated prognosis?

...

Roger, I'm staggered that you of all people post as if the argument is polar. There are one or two on here who seemingly labour under that belief, but for the most part those of us who accept AGW willingly, and repeatedly, make the point that there can be several effects occurring concurrently. It is for precisely this reason that through time CO2 might well both have lagged, and led, temperature change.

When Noggin starts her "we've levelled" arguments, she tends to overlook the possibility that what might just be going on is some natural cooling against a continuing backdrop of AGW. As TWS has previously pointed out, the acid test will be when the next Nino comes along.

There will ALWAYS be several factors at play: how else can we account for the historic variability in climate, albeit in bands rather below the heady heights we're at now.

All this bluster just because I had the temerity to post a link to a paper from a well respected, honoured and awarded climatologist who doesn't agree with the consensus view on AGW and CO2 in particular. ...- perhaps more reading and research on your part is required before leaping on other members of this forum.

Jethro, I read as much as almost anyone on here, and a lot more than most, and I usually get around to reading the links you post (as I did this afternoon), even though I know they'll be going down some vain search for an argument to denounce unending warming. What I sometimes wonder is whether YOU read fully the articles. This afternoon post, in the first paragraph as I recall, still acknowledged that CO2 was causing warming, the argument seemed to be the extent to which a wholly anthropogenic source could be blamed.

There was no bluster in my post - believe me, you know full when I'm in bluster. Perhaps the over-sensitivity is yours?

[jethro]

Jethro, you'll be trying to tell us that CO2 doesn't warm the atmosphere at all next.

Given that no CO2 means a cold world (see other atmospheres in our solar system), and that there is NO disagreement at all, anywhere, that the reason we have a temperate biosphere is because of the CO2 that we do have, then it would be remarkable indeed, would it not, if there were just two levels of warmth. None when there's no CO2, and around 290k when there is, say, 350ppm or so.

So, are you suggesting that additional CO2 does NOT lead to warming of the atmosphere.

Prophecies too eh?

So are you suggesting we know all we need to know then?

Jethro, I read as much as almost anyone on here, and a lot more than most, and I usually get around to reading the links you post (as I did this afternoon), even though I know they'll be going down some vain search for an argument to denounce unending warming. What I sometimes wonder is whether YOU read fully the articles. This afternoon post, in the first paragraph as I recall, still acknowledged that CO2 was causing warming, the argument seemed to be the extent to which a wholly anthropogenic source could be blamed.

There was no bluster in my post - believe me, you know full when I'm in bluster. Perhaps the over-sensitivity is yours?

And where did I say otherwise Stratos? Have I not endlessly said some, but not all temperature change is down to us?

Another version of CO2, it's role and impact:

http://www.biomind.de/nogreenhouse/daten/EE%2018-2_Beck.pdf

DISCLAIMER: Being posted purely to demonstrate there are many differing views, from many different scientists; exactly the same reason for posting the other link earlier.

[Stratos Ferric]

Prophecies too eh?

...

I don't see a prophecy, only a question.

Prophecies too eh?

So are you suggesting we know all we need to know then?

And where did I say otherwise Stratos? Have I not endlessly said some, but not all temperature change is down to us?

Another version of CO2, it's role and impact:

http://www.biomind.de/nogreenhouse/daten/EE%2018-2_Beck.pdf

DISCLAIMER: Being posted purely to demonstrate there are many differing views, from many different scientists; exactly the same reason for posting the other link earlier.

Another question. IF CO₂ levels historically have been higher than they are now (a moot point, but let's accept that they might have been, or that at least they have been around as high), is your assertion that all of the increase we're now seeing must, therefore, be natural?

...If China's winter is anything upon which to rest one's predictions, the future could be colder than some imagine. All the pollution in the air, yet temperatures fall five degrees below normal -- what does that suggest to any reasonable observer?

It suggests that they've experienced a one in fifty year weather event.

Can anyone explain to me why there is a tendency on the part of people to assume that any single cold event somehow dismisses a warming climate?

I spent less on my shopping last week than I did the week before, but that doesn't mean that prices aren't still going up all the time.

[HighPressure]

HP, I suspect there's a lot in that. CO2 (together with other anthropogenic GHGs) is, most probably now leading to secondary knock-on effects. We know warmer oceans absorb less CO2, so that's one obvious knock-on. We know a warmer world has less ice, thus lowering albedo; another knock-on, which then causes more ocean warming - a double whammy.

We do all concentrate on CO2, and it might be that this had a more dominant and exclusive role at the start of warming than it does now.

Either way, the issue is anthropogenic.

I just want to follow up and say that I believe in an amount of Warming caused by Human activities as I said I am of the view that Ozone is a major factor. But one thing to make clear is that in all honesty I have been unable to come to a conclusion of just how much AGW makes up GW, I cannot define the IPCC's "significant'?. Where I really become sceptical is on what we are told will happen if we reduce CO2 emissions, there is simply no evidence to suggest that we can even stabilise Global temps let alone reduce them. This does not mean I advocate no action on reducing emissions just that given that there could be significant natural factors beyond our control coupled with earlier human errors (CFCs) as well as CO2 emissions, to tell us that if we simply reduce emissions everything will ok is dishonest. I have a real feeling that the scientific community know this but are prepared to go along with these claims as some kind of greater good. I also believe that governments like ours do see GW as an opportunity to raise revenue on the back of a remedy which may well not exist?

I see on Sky news tonight a bit on tipping points, but they stated that we need to reduce CO2 emissions to avoid them. In reality my maths say that even with CO2 reductions these tipping point will probably be reached but this is just not been told to us: WHY?

I also noted on the BBC website that the UK Carbon emissions dropped by 0.01% in 2007, but the reality is that manufacturing continues to fall in the UK and imports continue to rise so our Carbon footprint actually rose in 2007 and probably had a worse global impact then the year before. Again I ask why is our own government entering into the world of creative accounting and playing the numbers game when they tell us how serious the issue is?

Edited February 5, 2008 by HighPressure

[Chris Knight]

Yes Jethro, I have read Roy Spencer's essay, which discusses the correlation of CO₂ and temperature.

The various CO₂ records all have a temperature signal, which not only varies with the various ocean indices, volcanic events and possibly solar activity (as well as "mundane" diurnal and annual periodicity). The mechanism behind these variations may have intuitively obvious explanations, but I'd like to see some clear and measured analysis first.

I find the various different "forcings" taken together with our small number and short period of measured records of CO₂ serve to confuse the issue of where the CO₂ is really coming from, where it is going to and why it is increasing.

I felt that Ferdinand Engelbeen's essay showed quite nicely how the data is obtained and processed, and that despite the much greater quantities of natural and preexisting atmospheric CO₂ dealt with every year by the "sinks", neither the sinks are failing and that the increase in atmospheric CO₂ is pretty likely due to human fossil fuel use and nothing else.