General Climate Change Discussion

[Thundery wintry showers]

What justifies 'probability' in such circumstances? 'Possibility' is surely the very best that can be said? And that is fairly generous.

If there is so much uncertainty over an issue, how can it therefore be deemed to be serious without understanding the wholse story? Or is it deemed serious based on the suppositions of AGW which make it serious? It is a 'probability' in your own eyes because you subscribe strongly to AGW theory.

There is no certainty over AGW but there is a lot of evidence for it. In these situations, it is possible to derive conclusions of what is most likely to be true, based on the current understanding of the climate system. From the evidence I've seen, I conclude that humans are almost certainly impacting on the climate system but that there is a significant possibility that it could be somewhat less than the IPCC suggest.

That argument is heavily flawed in any case. For example, if I see a simplified pressure chart in June with a flabby low sat over Scotland, but don't have access to the detail, and look outside and see sunshine, is it fair to say that I can't talk of a high probability of cumuliform clouds sprouting up during the morning and bringing heavy afternoon showers, or that I can't talk of "a higher probability than if the pressure chart showed a big fat high"?

As for "here is no evidence worth acting on atm that says that CO2 etc are having anything like the clout assumed to overide our climate beyond that of natural cyclical variability"- yes there is. There is no proof, but there's plenty of evidence- which of course is hotly disputed in many quarters, but I guess the reason you can't see the evidence is because it is incompatible with the premise that AGW is a non-issue, and doesn't threaten the existence of snowy ENE'lys for Hastings. I think you are much closer to being guilty of the kind of circular reasoning you accuse me of than I am.

And there seems to be a certain defensiveness of the idea that we shouldn't take potentially destructive action, as an argument against AGW. That isn't a very venomous attack on my position as I've always promoted the "no regrets" type policies that simply aim to move us towards more sustainable ways of living (and here I differ from the consensus among environmentalists, which is for much more draconian policymaking). And most of the action that would help stop AGW would also help stop the consumption of finite resources and move us towards sustainability- so my retort is, "why not do it, then?"

[Guest North Sea Snow Convection]

There is no certainty over AGW but there is a lot of evidence for it. In these situations, it is possible to derive conclusions of what is most likely to be true, based on the current understanding of the climate system. From the evidence I've seen, I conclude that humans are almost certainly impacting on the climate system but that there is a significant possibility that it could be somewhat less than the IPCC suggest.

That argument is heavily flawed in any case. For example, if I see a simplified pressure chart in June with a flabby low sat over Scotland, but don't have access to the detail, and look outside and see sunshine, is it fair to say that I can't talk of a high probability of cumuliform clouds sprouting up during the morning and bringing heavy afternoon showers, or that I can't talk of "a higher probability than if the pressure chart showed a big fat high"?

As for "here is no evidence worth acting on atm that says that CO2 etc are having anything like the clout assumed to overide our climate beyond that of natural cyclical variability"- yes there is. There is no proof, but there's plenty of evidence- which of course is hotly disputed in many quarters, but I guess the reason you can't see the evidence is because it is incompatible with the premise that AGW is a non-issue, and doesn't threaten the existence of snowy ENE'lys for Hastings. I think you are much closer to being guilty of the kind of circular reasoning you accuse me of than I am.

And there seems to be a certain defensiveness of the idea that we shouldn't take potentially destructive action, as an argument against AGW. That isn't a very venomous attack on my position as I've always promoted the "no regrets" type policies that simply aim to move us towards more sustainable ways of living (and here I differ from the consensus among environmentalists, which is for much more draconian policymaking). And most of the action that would help stop AGW would also help stop the consumption of finite resources and move us towards sustainability- so my retort is, "why not do it, then?"

It's a shame that you had to add that part as it doesn't do me justice I don't think. I have said enough times that I might have started with the 'closed ears and mind' approach (like many others) on this subject but have tried to read into the background of this subject (as much as I am able to understand) with a much more open mind. It is because of this that I can now say what I say because I haven't, in all honesty, seen or read anything to convince me further about AGW. So I think I deserve a bit more credit than that.

My own suggestion that you will see the probabilities of AGW and therefore subscribe to action now on it, is because I am assuming that you reach your own conclusions through similar valid means in terms of how you interpret what you see, read and hear. So there was no accusation, personal 'attack' nor disrespect intended in what I said.

I was merely expressing my disagreement with the opinion and was rather puzzled about a bit of what you had said. Internet words don't always convey the right expression. Smilies don't come as easily in this section somehow as on the weather section!

I think the idea that the action designated to treat AGW is also a 'cure-all' environmental palliative rather constitutes a 'get-out' clause for AGW proponents if it all proves wide of the mark. It may well be indeed that some of the measures assist general environmental issues (aside from climate) where there are KNOWN problems and I have, as I would hope you know have seen, previously already supported that.

But I have also clearly said that I do not agree that everything should be inextricably linked to climate change and by putting sceptics in a 'catch 22' situation by appearing to contradict themselves in terms of being hesitant in terms of action on the basis of climate change misses the point that action should be done for the right relevant reasons and not for the wrong one's.

And not every charter proposed is a 'cure-all' palliative by any means anyway.

Edited April 3, 2009 by North Sea Snow Convection

[Guest]

As a bystander in this discussion and not qualified to enter the technical part of the dispute, I can say that in the experience of my lifetime, the climate has become warmer generally. No doubt there are natural cycles involved as there were in the middle ages when it was warm enough for the Vikings to settle parts of Greenland. This was followed by the little ice age.

Not enough appears to be known about the causes and effects of these episodes, neither the causes of the onsets of the ice ages and their retreats.

In fact I have always been taught that at the moment we are still in an inter glacial period which at some time in future could revert back to being a full blown ice age.

At the same time human activity does influence the weather. Think of the "Pea Souper" fogs we used to have before the Clean Act, think of the pockets of relative warmth in urban areas. Since the introduction of this Clean Air Act in the 60's, fogs, especially really thick fogs, have reduced damatically, so it shows we can have some control to an extent.

I also understand that the Romans deforested large tracts of North Africa to grow grain for their Empire. The forests never grew back and the land eventually became desert.

Prior to the Industrial Revolution few fossilised fuels were used; since then the amount of CO2 in the atmosphere has gradually risen. There are lots of other greenhouses gases also put into the atmosphere, some far more effective in warming than CO2, such as methane, a lot of which, is being generated by our methods of disposal of rubbish and some more by the flatulence of cattle. Though is this something in common with all herbivores?

Some of the things we can do something about such as curbing the amount of CO2 we are creating and finding better ways of rubbish disposal, which if we are unable to prevent the production of methane, then perhaps find methods of harnessing it to use as fuel.

Some appear to be certain of global warming whilst others are sceptics. At the same time vast sums are being spent on both sides, some funded by people with vested interests and it seems relatively few people with a really open mind on the subject.

I take the view that there is anecdotal evidence to support global warming and we would well have a situation where the global warming is masking the effects of a cooling period.

It makes sense to me that we should take notice of the possibilities and take the appropriate action. After all we still buy insurance for our houses, though we do not really expect to be burgled.

Edited April 3, 2009 by mike Meehan

[Chris Knight]

Firstly a good debate all round, but I have to agree with this post, if you set out a proposition whether it be natural cycles or AGW you must exhibit evidence to make your case. I would still like to know if any paleoclimatologists are sceptics and if not why not because surely their knowledge is central to the debate. As I understand it much evidence of sudden climate shifts is now coming to light outside of known climate cycles and there is much debate on what was the driving force behind those shifts, also we have no idea how much forcing is necessary to tip us into a sudden climate shift it seems to me to be likely that our actions could tip the balance if they go on unchecked and it is possible that they have already done so, time as ever will tell.

Here's one - Bob Carter:

Professor Robert (Bob) Carter, is "a researcher at the Marine Geophysical Laboratory at James Cook University", Australia. [1] In a byline with an op-ed published in the Sydney Morning Herald in September 2005, he was described as an "experienced environmental scientist" [2], but a March 2007 article in the same paper noted that "Professor Carter, whose background is in marine geology, appears to have little, if any, standing in the Australian climate science community." [3] He is a well known climate change skeptic.

Carter is a speaker at the International Conference on Climate Change (2009), organized by the Heartland Institute think tank. [1]

Carter could well be described as "a prominent research geologist with a personal interest in the issue of climate change," from his list of research papers. He has extensive experience of paleoclimatic research, including participation in Ocean Drilling Program Leg 181 in the southwest Pacific, which described the benchmark 4 million year-long, mid-latitude climate record from Site 1119 [4]

[weather eater]

Here's one - Bob Carter:

Thanks for that Chris, just looked him up, seems he has a few iffy connections including these people http://en.wikipedia.org/wiki/Institute_of_Public_Affairs and that makes him suspect to my mind, do you know of any others who are proven free of political agendas. As soon as the words right wing or left wing think tank appear I suspect bullsh*****

[Gray-Wolf]

El Nino does not have much impact on Arctic temperatures, it's mainly in the tropics where we see a big difference. 1998 for instance was not a particularly warm year in the Arctic, and there wasn't a major ice melt that summer.

I am at a loss ( again ) here.

We know that ocean currents may take in excess of 100yrs to go from surface, via subduction, to re-surface.

How are you so sure of your facts here TWS?

How can you say that excess energy in the system is lost???

I ask in honesty as I need to know such things to help me in my understandings as, the way I see things now, I'm desperate for an alternative understandings that rings as true as my current stance.

[MR EXTREMES]

there have been a fair few number of top forecasters who there selfs have openly said that man made gw is a complete joke.

and there pretty well educated in this field im very much a skeptic i admit,

but not very educated in this subject but strongly feel planet earths climate is going to throw egg on the faces of the gw camp (or should i say with help from our sun).

im happy to sit back and yes of coarse do my bit on for our planet as i said before theres nothing wrong with a cleaner planet and there are ways of not milking our planet of all of it resources.

there is noway you can say thease gw people no anything about how our climate shifts all they do know is its runs cold and hot and this has gone on for the complete lifetime of our earth.

ok so do they know how old planet earth is,

dont tell me they do because i will wet myself laughing because they dont everything is roughly or over estimated or under estimated.

just like temp projections for the future well there not correct already lets wait and see for another few years and how strange that the same people that project this warming also have been suggest a either cooling or stable temp projections for the next few years or more mmm strange.

so its not worth anyone saying this planet is doomed the biggest threat is nuclear war or terrorist attack,

but i wont do no more for our planet because what will be will be if gw is fact then i eat my hat.

i do think it is more likely we are now heading through a cooling period and yes ok then it will warm so thats is what is called a normal earth climate cycle.

i think gw is a scam a big political joke.

i have noticed that since the 80s winters have become less cold well not hard to answer that.

1. where coming out of a mini ice age.

2. the suns activity picked up and defrosted us lol.

and now the sun is having another rest and before long our climate will be once again cold when it wakes up it will warm again.

the sun is the one player that has the biggest influence on our planet thats fact.

and what ever happens mother nature will do what she will do,

and man made gw cant be reversed is that fact no of coarse not because if it does all kick off and most of us get whiped out then the climate will change again then the cycle starts from scratch.

either way global warming or cooling will have a effect in the end but my view is lets all focus on warming and forget cooling because its less likely and will have less effect because of warming lmao.

funny how cooling climate gets less research than the oposite side after all the usa has not been suffering with extreme cold winters in the last few years and that glaciers are not growing and cold records are not being broken around the world in the last couple of years or more,

all this dont matter because where blinded by the man made gw theory we ignore another major threat.THE ICE AGE but it makes no difference because you cant stop that either.

and it will happen.

[BLAST FROM THE PAST]

Neither have national economies, national crime statistics, national immigration statistics etc followed their respective models. Should we simply abandon all theories as rubbish?

[MR EXTREMES]

blast

agreed that makes sence .

[Chris Knight]

Thanks for that Chris, just looked him up, seems he has a few iffy connections including these people http://en.wikipedia.org/wiki/Institute_of_Public_Affairs and that makes him suspect to my mind, do you know of any others who are proven free of political agendas. As soon as the words right wing or left wing think tank appear I suspect bullsh*****

Any geologist, like Carter, involved in drilling programs is, of course, funded partly or entirely by petrochemical interests (often on the basis that the institution they find themselves working for is funded by grants from such business sources), and therefore tarred with the tag "Big Oil". Funnily enough if anyone cares to look at the CV of Pachauri, chief honcho & mouthpiece of IPCC - you can immediately see he was involved in the oil and gas business, as an economist, mind you, not as a physical scientist.

I think that this iffiness by association is prejudice of the first kind, including my exemplification of Pachauri, which is not meant as an ad-hominem criticism of the man, just a paradigm of how the slur works in practice.

Please read the (scientific, and critical) publications of Carter - there are plenty of direct links in the link I provided to make up your own mind if the fellow is a raving denialist or a genuine scientist (or both!) rather than the precis' of those who would praise or castigate him on their own prejudicial grounds.

I am not saying I 100% agree with Carter either, but at least he is open and outspoken about his understanding of the climate debate, and his palaeoclimatological credentials are open to scrutiny.

[Chris Knight]

I am at a loss ( again ) here.

We know that ocean currents may take in excess of 100yrs to go from surface, via subduction, to re-surface.

How are you so sure of your facts here TWS?

How can you say that excess energy in the system is lost???

I ask in honesty as I need to know such things to help me in my understandings as, the way I see things now, I'm desperate for an alternative understandings that rings as true as my current stance.

I understand why you are lost GW - you attempt to equate energy to temperature. It is an easy trap to fall into.

Energy as heat is short lived. James Watt, and other steam energy pioneers, understood and exploited the fact that you could use water, a common substance on earth, to transduce heat into mechanical energy. He understood some of the properties of the atmosphere, water and energy in the form of heat that drives the great engine of the weather and climate. He understood that an energy source provides heat, that water was an excellent means of transforming that heat into a source of mechanical energy, because it trapped the energy until it changed phase and then could exert tremendously greater mechanical energy as a gas than as a liquid.

(He also realised that as well as a potential energy source, it was also a latent energy source - he could have also become a refrigeration engineer or heat pump specialist - should the demand have arisen at that time.)

Energy as radiation is very short lived. This planet transduces energy in many ways. Radiation as longwave is a sure means to lose the energy into space. However, if we follow the really energetic weather pathways in the earth's atmosphere, we understand why the industrial revolution followed the rather reliable conversion of heat energy from liquid to gaseous water, and not the rather limpid, but pretty conversion of dry ice to ankle high fog, because CO2 is merely a biproduct, not a major player.

The former allows great empires to be founded, and the traditions of slavery to be ended on a wealth of all nations through honest trade, the latter allows sequined youth to dance themselves into hedonistic destruction through narcissistic addiction to S&D&R&R, and then to waste all that CO2 in removing the only worthwhile component of coffee, caffeine.

Edited April 3, 2009 by Chris Knight

[weather eater]

Any geologist, like Carter, involved in drilling programs is, of course, funded partly or entirely by petrochemical interests (often on the basis that the institution they find themselves working for is funded by grants from such business sources), and therefore tarred with the tag "Big Oil". Funnily enough if anyone cares to look at the CV of Pachauri, chief honcho & mouthpiece of IPCC - you can immediately see he was involved in the oil and gas business, as an economist, mind you, not as a physical scientist.

I think that this iffiness by association is prejudice of the first kind, including my exemplification of Pachauri, which is not meant as an ad-hominem criticism of the man, just a paradigm of how the slur works in practice.

Please read the (scientific, and critical) publications of Carter - there are plenty of direct links in the link I provided to make up your own mind if the fellow is a raving denialist or a genuine scientist (or both!) rather than the precis' of those who would praise or castigate him on their own prejudicial grounds.

I am not saying I 100% agree with Carter either, but at least he is open and outspoken about his understanding of the climate debate, and his palaeoclimatological credentials are open to scrutiny.

Thank you Chris I did indeed read them, of course the trouble with all this stuff from both sides of the argument is that it is made up of data which can be used to present whatever answer you want as indeed Mr Carter rightly points out, unfortunately this is being done by both sides of the debate and leaves the true sceptic (by that I mean somebody who really is unsure who to believe) none the wiser.

If we look at a small section of climate history the little ice age, there is still much debate over dates and areas effected about 1650 seems to be a popular start date but others put it much earlier when the climate began the change from the medieval warm period, also location seems to play a part in defining when the LIA began making it at times a local rather than global event. The point being when I hear people say the science behind AGW is not settled or misinterpreted or even just plan wrong the same applies to the science behind natural cycles as I pointed out in my earlier post, my own view is that it’s a combination of the two.

The consensus of opinion is that we are entering into a cooling period and we have indeed seen a levelling off in global temperatures but as yet I see no true fall, thus it seems to me the next few years are crucial to those that maintain that natural cycles are the important factor behind the warming, the warming that all sides of the debate agree has happened.

Of course science in relation to climate and climate history is an on going learning curve and that leads in my mind to major doubts over the credibility of the arguments from both camps on the climate thread. My worry is that in-action on the possible implications of climate change will lead us to digging a hole that it might be impossible to get out of if the AGW camp are right. And indeed the more I’ve read about Natural cycles the more worried I become as there seems to a growing consensus amongst paleoclimatologists that the earths climate can shift very quickly indeed in response to drivers we don’t yet understand thus it becomes less important as to whether CO2 is the driving factor behind climate change but whether its contributing to it in a substantial way. In other words the dangers of AGW are being enhanced by natural cycles rather than negated.

[jethro]

There's an interesting article in New Scientist by Nora Schultz, dated 2nd April; it talks about a natural mechanism which caused the Medieval warm period and then goes onto explain why it couldn't be responsible for modern warming.

The article has copyright issues written all over it, hence providing no abstract or link, it can however be found here:

http://climatedebatedaily.com/ 3rd one down in the calls to action column.

Not sure how it could explain the peer reviewed stuff from China which also gives evidence of a MWP.

[noggin]

http://solarscience.msfc.nasa.gov/SunspotCycle.shtml

I find this heartening.....at the end of paragraph headed "The Maunder Minimum" is the following sentence:

"The connection between solar activity and terrestrial climate is an area of ongoing research".

I find it heartening because previously the Sun has been all but discounted as having an effect in the warming of the 80s and 90s.

I wish the researchers all the best in this work and I hope that it will be done without any preconceived notions and without any political interference and without any self- agrandissement.

[Chris Knight]

There's an interesting article in New Scientist by Nora Schultz, dated 2nd April; it talks about a natural mechanism which caused the Medieval warm period and then goes onto explain why it couldn't be responsible for modern warming.

The article has copyright issues written all over it, hence providing no abstract or link, it can however be found here:

http://climatedebatedaily.com/ 3rd one down in the calls to action column.

Not sure how it could explain the peer reviewed stuff from China which also gives evidence of a MWP.

Look on the bright side - the MWP has been rehabilitated, and can come out of the closet once more. At least one more wiggle can be reinstated in the climate record. Those who attempted to deny it existed now don't have to.

Edited April 10, 2009 by Chris Knight

[Devonian]

Look on the bright side - the MWP has been rehabilitated, and can come out of the closet once more. At least one more wiggle can be reinstated in the climate record. Those who attempted to deny it existed now don't have to.

Hey, Chris, it's strawmen time...

Who is denying there wasn't a MWP in NW Europe? Names please.

There certainly seems to have been one in NW Europe. What is in question is the magnitude of the MWP, how synchronised it was and whether it was global. If you look at the AR4 recon spaghetti graphs they all show a MWP of sorts - so who is going to deny the MWP's existence? Again, please name those who deny that.

[Solar Cycles]

Hey, Chris, it's strawmen time...

Who is denying there wasn't a MWP in NW Europe? Names please.

There certainly seems to have been one in NW Europe. What is in question is the magnitude of the MWP, how synchronised it was and whether it was global. If you look at the AR4 recon spaghetti graphs they all show a MWP of sorts - so who is going to deny the MWP's existence? Again, please name those who deny that.

Well Hansen as tried his best to smoothe away it's impact Dev! Seems there was plenty of evidence to be found, before it was decided that the MWP was a thorn in the side, off a theory already under scrunity!

[Devonian]

Well Hansen as tried his best to smoothe away it's impact Dev! Seems there was plenty of evidence to be found, before it was decided that the MWP was a thorn in the side, off a theory already under scrunity!

That's an answer...but not to my question. I'll put it again, in case you missed it, "Who is denying there wasn't a MWP in NW Europe? Names please.". I'll go further, who is denying the was an MWP, names please?

[BLAST FROM THE PAST]

That's an answer...but not to my question. I'll put it again, in case you missed it, "Who is denying there wasn't a MWP in NW Europe? Names please.". I'll go further, who is denying the was an MWP, names please?

How about all those that championed Hansen and his graph? Did you?

BFTP

[Devonian]

How about all those that championed Hansen and his graph? Did you?

BFTP

Huh? 'Hansen'? What graph? What 'did you'? And what's that got to do with denying the MWP? Again who is denying there wasn't a MWP in NW Europe? Names please. I'm sure Dr Hansen isn't.

[Essan]

I'm still confused as to why the deniers are so obsessed with the MWP? Not as though it was the warmest period, even in Europe, of the last few thousand years.

[Solar Cycles]

I'm still confused as to why the deniers are so obsessed with the MWP? Not as though it was the warmest period, even in Europe, of the last few thousand years.

I think you know why Essan! Maybe because the warmist are hell bent on denying, that the MWP was warmer than today, in order to prop up a theory, which as little evidence to back up it's claims. Hence Mr Hansen, decided to set about tackling this thorny issue!

[Chris Knight]

Hey, Chris, it's strawmen time...

Who is denying there wasn't a MWP in NW Europe? Names please.

There certainly seems to have been one in NW Europe. What is in question is the magnitude of the MWP, how synchronised it was and whether it was global. If you look at the AR4 recon spaghetti graphs they all show a MWP of sorts - so who is going to deny the MWP's existence? Again, please name those who deny that.

Perhaps you should ask the New Scientist's journos and editors, Dev, they seem to think that a lot of folks have been led to believe in a non-existent MWP as supposed by respected (and now outmoded) figures in the past such as Hubert Lamb, and that Briffa and others have gone to great lengths in AR4 {chap. 6.6, fig 6.10, explained in detail in (box 6.4)} to convince governments that such climate extremes not only did not (likely) happen in the past, but do not happen except (very likely) by human intervention, by increasing carbon dioxide levels in the atmosphere post-industrially by continued burning of fossil fuels, as we see today.

Better still, ask your friends in Exeter, they will (very likely) have the best answers.

[Devonian]

Perhaps you should ask the New Scientist's journos and editors, Dev, they seem to think that a lot of folks have been led to believe in a non-existent MWP as supposed by respected (and now outmoded) figures in the past such as Hubert Lamb, and that Briffa and others have gone to great lengths in AR4 {chap. 6.6, fig 6.10, explained in detail in (box 6.4)} to convince governments that such climate extremes not only did not (likely) happen in the past, but do not happen except (very likely) by human intervention, by increasing carbon dioxide levels in the atmosphere post-industrially by continued burning of fossil fuels, as we see today.

OK, I wont try again. No one has named anyone who has denied there was a MWP - because no one does!

Chris, do you think that people like 'Briffa' did a honest study and found out things and honestly reported that? Because you seem to me (that's seem - the written word can be hard to interpret) to be saying he didn't do that - 'led to believe...great lengths...to convince'.

Better still, ask your friends in Exeter, they will (very likely) have the best answers.

What do you mean by 'the best' answers?

[Essan]

I think you know why Essan! Maybe because the warmist are hell bent on denying, that the MWP was warmer than today, in order to prop up a theory, which as little evidence to back up it's claims. Hence Mr Hansen, decided to set about tackling this thorny issue!

Well firstly there's no evidence that it was any warmer and secondly it doesn't matter, because it was warmer before then.

And even if it was 5c warmer or 2c colder than today makes exactly 0.0000000000000000 difference to the impacts of human activity on climate today. So it's a complete red herring anyway! The only people who ever said the MWP was warmer are the people who want you to think that whatever you do has no effect on the planet whatsoever. Stop listening to the flim flam man. His snakeoil isn't the elixir he claims it is. Trust me

Edit: what we should be thinking about is the cause of the LIA - why it started and perhaps more especially why it ended. The Medieval and Modern warm periods are only 'warm' in comparison with the LIA. And were it not for the LIA the MWP would cease to exist.

Edited April 11, 2009 by Essan