General Climate Change

[jethro]

How so Jethro?

If we sit back whilst we suspect we are throwing 'our' finely balanced system out of kilter, bringing with it sea level rises, droughts across productive areas, more extreme storms then are we not culpable for the loses we foresaw and chose to ignore?

Surely the wise course (and most humane) is to be looking at mitigating the impacts we foresee, and fear most???

From your personal experience do you not wish that folk had acted differently across sub-Saharan Africa through the late 70's early 80's and do you not wish we all had better knowledge of what was occuring then so as to be able halt it far sooner?

You are not judge and jury Ian.

Your judgement and dolling out of sentence to an individual not in control of either the climate nor the world's response to climate change would be laughable if it were not bordering on offensive.

Drought in Africa back in the 70's and 80's - we've had those discussions already, it has no place in these discussions, the causes are well known and are not connected to climate change or more specifically AGW.

Your opinion is one among many others, you are entitled to that opinion, as is everyone else. Please respect the differences in those opinions and refrain from trying to impose your opinion upon others. You are again crossing the line between voicing opinion and evangelising, not everyone is Lovelockian in their approach to life; as with all belief systems in the world, there are followers and those who choose otherwise.

On the subject of Lovelock, why not open a new thread devoted to him where more detailed discussions could be had on the why's, how's and reasons for him being right.

[Pennine Ten Foot Drifts]

But are we talking about belief systems here ? I can't see anything offensive in what G-W is saying. Surely all he's saying is that where there is enough evidence that man's behaviour is having a detrimental effect shouldn't we accept responsibility and try to do something about it, rather than absolving ourselves of any possible blame (is this the word that scares people so much I wonder ?) by claiming either that we 'can't do anything anyway so why bother worrying' or that we don't 'believe' in the science so therefore can ignore it ?

Is the human race capable of concerted action, or are we all just unconnected individuals who can all claim 'it's not my problem', 'it's beyond my power to do anything', 'I don't believe in it so I'm opting out' and so on ? If that's the case are we able to change anything 'big', or are we all just helpless passengers ???

[jethro]

YS is talking about science and he's correct, there is a lot of evidence to support the theory that although warming has occurred, the majority of it is natural in origin.

There is a giant leap being taken that doubting the extent of AGW (based upon sound, scientific evidence) is also a reason for despoiling the planet and carrying on a little self journey of wanton waste. This assumption is continually made and is nothing more than a moral judgement designed to make the accuser feel superior and the accused guilty of causing, or contributing to disaster for which they must take personal responsibility.

Laser is probably one of the most ardent sceptics of AGW on this forum, as he has explained time and again, he lives a life in balance with nature, concientiously avoiding waste and consumption.

One does not automatically discount the other.

[Methuselah]

Solar, Lunar, Oceanic heat distribution. These are not political tools Pete, there is as much evidence for these, as there is for AGW. Maybe if a fraction of the funding, went into natural cycles as to what is pumped into AGW, then we would have a more balanced view of what is actually the cause! Still let's leave the political waffle to the green brigade!

Hi Solar...

Yes, there are myriad natural forcings in operation; there have always been. But, as of themselves, they don't suggest that AGW is a scam - only that it (AGW) might be being overestimated (or even underestimated?)...Both of which are, of course, always possible...Science is not religion?

Sorry TWS but it is my belief that you are mistaken here.

There is now a lot of evidence that the warming (that has undoubtably occurred) can be explained by natural cycles and changes in global cloud cover (associated with the coupled oceanic / atmposheric cycles).

As such it is becoming increasingly clear,that although CO2 is a greenhouse gas, and yes is contributing to the global warming scene, ... it is a minor and not a major player. Furthermore, it is the misguided notion that the climate system is predominatly sensitive (via positive feedback mechanisms) rather than tolerant (via feedback and forcing mecahnisms combined) that is skewing the IPCC global forecast models 'predictions' for the future.

Clearly new satellite data and recent publications on the solar cycles and perhaps most importantly PDO cycles cast huge doubt on the singular anthropgenic greenhous gas theory.

Y.S

Does this evidence come from research funded by big coal and big oil, perchance?

[Devonian]

Sorry TWS but it is my belief that you are mistaken here.

There is now a lot of evidence that the warming (that has undoubtably occurred) can be explained by natural cycles and changes in global cloud cover (associated with the coupled oceanic / atmposheric cycles).

I don't think there is any such credible evidence. But, perhaps you can post something from a reputable source (NOAA, Hadley Centre, a university atmosphere science dept for example) that the warm can be explained by, and you imply only by, natural cycles and the rest. There is NO such evidence.

As such it is becoming increasingly clear,that although CO2 is a greenhouse gas, and yes is contributing to the global warming scene, ... it is a minor and not a major player. Furthermore, it is the misguided notion that the climate system is predominatly sensitive (via positive feedback mechanisms) rather than tolerant (via feedback and forcing mecahnisms combined) that is skewing the IPCC global forecast models 'predictions' for the future.

Sorry, but this does not follow.

Clearly new satellite data and recent publications on the solar cycles and perhaps most importantly PDO cycles cast huge doubt on the singular anthropgenic greenhous gas theory.

Y.S

But, above, you say that 'the warming (that's all of it) can be explained without any AGW. That is, tbh, preposterous.

Edited May 24, 2010 by Devonian

[Gray-Wolf]

I think maybe folk need re-examine our climate sensitivity. I think we all agree that climate see-saws between short term warming and cooling under a plethora of natural forcings (and nothing disastrous for the planets ecosystem becomes of them.........though the odd human civilisation may have fallen foul to such perturbations) but what if we add in a novel forcing on top of this natural cycle? what id that 'novel forcing' exists through both a natural 'cool phase' (and moderating it) and then on top of a natural 'warm phase'?

May we be pushing the envelope too far for 'natural' checks and balances to cope? May Nature need to take things to a different climate setting (climate shift to a 'warm' setting?) to cope?

We need to look for the natural mechanisms that suggest such a step change is about to occur and lay plans to cope with it.

The Carbon cycle seems to underpin both 'warm' (more CO2) and 'cool' (less CO2) climate settings. If we are pushing the 'warm' button we need look for extra carbon being placed into the system that does not have a human origin (fossil fuels,deforestation,land use changes etc.) like CO2 from permafrost melt/Methane from permafrost melt, soils drying and releasing CO2, Forrest die back and CO2 release, CO2 sink imbalances, warming oceans etc.

[Admiral_Bobski]

At the risk of perpetuating an argument which should not be perpetuated, I have to support Jethro in taking issue with GW's comment to YS earlier on.

This comment, "We all know 'history will tell all' but if you are wrong Y.S. your complacency condemns millions to death" is similar to others that have arisen over the years I have been on here - the insinuation being that by "denying" AGW you are somehow an accomplice to manslaughter (at best) or murder (at worst). This is a perfectly reprehensible allegation to make of anyone.

Perhaps, if we are to follow this trend, it is perfectly acceptable to accuse Gray-Wolf of aiding and abetting the mass brainwashing of the next generation with his AGW propoganda?

Is that not an offensive insinuation? And, if so, is Gray-Wolf's comment to YS not equally offensive? In fact, is it not even more so, since having the blood of millions on your hands is surely worse than moulding others in your image?

This is the kind of rhetoric which is likened to religious fervour, and it is best left out of these discussions.

CB

[Gray-Wolf]

C-Bob, we have been here before and I have offended your sensibilities with similar in the past (and always apologised for any discomfort I brought you for having you interpret such as a personal 'slur').

This is not a matter for us to 'judge' but merely my perception of how history will 'Judge' this generation for it's complacency at matters which ,by then ,will be oh so clear.

My hands are as bloody as yours or anyone else's (and no matter how 'Pilate' I be about it I cannot wash off this stink/stain) and ,as ever, our children will despair at the gaffs we have made.

At risk of being overlong 'Y.S.'s' complacency is that of the group to whom he adheres to and (it would seem from the words the poster uses) who feel we have no need for alarm/concern at the state of the climate system (or the projections science brings us as to the direction the climate system is headed in) and not a direct assault on the poster themselves. It is that 'set' of people, that 'clan' ,that 'ideology'.

If anyone else feels I have laid humanities fate at the feet of Y.S. (and have urged the global population to blame that poster alone for any large scale humanitarian disaster that our climate meddling brings us) I am sorry, I have been clumbsy, I will try and be less so in the future but can make you no promises.

Edited May 24, 2010 by Gray-Wolf

[Yorkshiresnows]

I don't think there is any such credible evidence. But, perhaps you can post something from a reputable source (NOAA, Hadley Centre, a university atmosphere science dept for example) that the warm can be explained by, and you imply only by, natural cycles and the rest. There is NO such evidence.

Sorry, but this does not follow.

But, above, you say that 'the warming (that's all of it) can be explained without any AGW. That is, tbh, preposterous.

Hi,

Nope, I stand by all of the above. What is preposterous is your narrow minded and quite dissmissive posts without looking into what is being stated.

You need to go and look at the wider scientific picture. I have. For your information, previously I was a AWG beleiver and believed as you do that global warming was caused by man's misuse of the environment and output of green-house gases.

What I have read and looked at (some of which I have referenced - its not my fault if you cannot be bothered to look at recent literature) has moved me away from these earlief views.

The green house gas theory has some big flaws which have not been adequatly explained or investigated.

I have never ever said that we have not warmed, also I have never said that Co2 is having no effect. Clearly we have warmed, it is the main cause of the warming that I question.

Fact 1: A doubling of CO2 from pre-industrial levels to around 500-550ppm is widely accepted to only itself be able to force a warming of around 1 degree C. This is atmospheric warming which would result in approx 0.5 to 0.6 degree C on the ground). Everybody seems happy with this.

Fact 2: The IPCC forecasts which vary from a warming of 1.5 (minimum) to over 6.0 degrees C is based on the presumption (for which there is absolutely no concrete evidence) that the climate system is very sensitive and all feedbacks will be positive. They believe that cloud cover changes as a result of warming will amplify the warming.

What has never been made clear is that there is a lot of controversy as to whether cloud pattern changes are a result of any warming, or actually cause a forcing themselves, How this actuall would occur and the distribution of any change and effect.

Fact 3: There is satellite data available from the last 10-20 years that at the very least suggest that forcing and feebacks from cloud cover changes occur throughout each and every year, that is, clouds are the key and can have dramatic effects on the amount of solar radiation absorbed by the Earth.

The PDO cycles are associated with warming and cooling phases of the climate. Our most accurate satellite data from 2000 through 2008, show that the PDO impacts on the Earth's energy balance. Over the 9-year satellite period of record, the radiative imbalance varies over a range of 2.5 watts per metre square. Although this natural source of radiative forcing is only 1 percent of the average flows of sunlight into and infrared radiation out of the system, Roy Spencer has shown , via a simple computer model run on a home computer that this is itself sufficient to explain over 75% of the warming experienced during the 20th century.

Thus, the PDO itself can potentially explain most of what we popularly call global warming.

And, whilst the anthropogenic explanation for global warming involves a forcing mechanism that can only be computed theoretically, the PDO forcing mechanism (a natural player) is actually observed by satellites.

A recent publication has also made the connection between the PDO and climate change (D.H Douglass and R.S.Knox "Ocean heat content and Earth's radiation imbalance". Physics letters A, 373 (2009): 3296-3300)

I enjoy this forum immensly and have learned and continue to learn a great deal from it, I am also aware of certain posters views and beliefs ..... all valid and I have no problem with any of them posting. But, I do take offence at some of the recent posts aimed at ridiculing some of the information I have offered, clearly without bothering to check up on what has been said.

I have now read 8 books and countless scientific papers and what myself and others are pointing too is that perhaps (not saying for absolute certainty ... though I am getting closer day by day) is that there is more uncertainty around AGW than some think and contrary to the IPCC consensus, there are natural cyclical explanations for the late 20th century warming that has liitle to nothing to do with greenhouse gas emissions by the human population.

I would also state that personally I am happy to curb greenhouse gas emissions and transfer the world economy to a greener footing, this would be brilliant ..... I am just discussing and looking at what has caused the recent warming.

I do have graphs and charts that I should post, but these will have to wait for another time (I travel a lot and do not have access to my home files).

Y.S

[Admiral_Bobski]

C-Bob, we have been here before and I have offended your sensibilities with similar in the past (and always apologised for any discomfort I brought you for having you interpret such as a personal 'slur').

<snip>

Perhaps you misunderstand - nobody thinks that you are laying the blame solely at YS's feet, but your wording is extremely personal.

What I am suggesting is that you take a moment to read your posts through before submitting them, take a moment to put yourself in the shoes of the person at whom they are directed and see whether you would be happy if someone else wrote those things to you.

If you genuinely fail to see how a post such as your earlier one might be construed as being offensive or insulting then might I suggest that perhaps you lack the capacity to play Devil's Advocate, and perhaps that is the reason why you are unable to entertain the notions of the skeptics.

Looking at the alternative viewpoint in a debate is absolutely crucial - it is certainly not anti-scientific to play Devil's Advocate. On the contrary, I think that it is an absolutely essential part of the scientific process. For example, you cannot seem to entertain the idea of the LI precisely because you are so hung up on the concept that CO2 is a main driver of climate. Looking at the LI hypothesis (if I may call it that at this stage) absolutely demands that preconceptions to the contrary be temporarily suspended, or else how can one analyse its potential merits?

I think that this is a crucial discussion that needs to be had - a look at how preconceptions colour our interpretation of facts, how important it is to be able to properly explore the counter-arguments in an analytical, rather than dismissive, way - but I feel that I may have pressed this point for too long.

CB

[laserguy]

My hands are as bloody as yours or anyone else's (and no matter how 'Pilate' I be about it I cannot wash off this stink/stain) and............

Well thanks for clearing that up GW. Much as I like you,you invariably wind me up terribly with every post as you come across as the High Priest of Righteousness and everyone but yourself is responsible for the catastrophe you are so sure is coming. Actually,most 'warmists' do exactly the same trick,and it does their cause no favours - no favours at all.

[Devonian]

Hi,

Nope, I stand by all of the above. What is preposterous is your narrow minded and quite dissmissive posts without looking into what is being stated.

Oh, you'd therefore be surprised how much time I spend reading WUWT and the posturings of the Heartland Institute...

You need to go and look at the wider scientific picture. I have. For your information, previously I was a AWG beleiver and believed as you do that global warming was caused by man's misuse of the environment and output of green-house gases.

What I have read and looked at (some of which I have referenced - its not my fault if you cannot be bothered to look at recent literature) has moved me away from these earlief views.

The green house gas theory has some big flaws which have not been adequatly explained or investigated.

I have never ever said that we have not warmed, also I have never said that Co2 is having no effect. Clearly we have warmed, it is the main cause of the warming that I question.

Fact 1: A doubling of CO2 from pre-industrial levels to around 500-550ppm is widely accepted to only itself be able to force a warming of around 1 degree C. This is atmospheric warming which would result in approx 0.5 to 0.6 degree C on the ground). Everybody seems happy with this.

Fact 2: The IPCC forecasts which vary from a warming of 1.5 (minimum) to over 6.0 degrees C is based on the presumption (for which there is absolutely no concrete evidence) that the climate system is very sensitive and all feedbacks will be positive. They believe that cloud cover changes as a result of warming will amplify the warming.

It's water vapour changes not cloud cover, water vapour feedback warming - clouds are not water vapour!

What has never been made clear is that there is a lot of controversy as to whether cloud pattern changes are a result of any warming, or actually cause a forcing themselves, How this actuall would occur and the distribution of any change and effect.

Fact 3: There is satellite data available from the last 10-20 years that at the very least suggest that forcing and feebacks from cloud cover changes occur throughout each and every year, that is, clouds are the key and can have dramatic effects on the amount of solar radiation absorbed by the Earth.

The PDO cycles are associated with warming and cooling phases of the climate. Our most accurate satellite data from 2000 through 2008, show that the PDO impacts on the Earth's energy balance. Over the 9-year satellite period of record, the radiative imbalance varies over a range of 2.5 watts per metre square. Although this natural source of radiative forcing is only 1 percent of the average flows of sunlight into and infrared radiation out of the system, Roy Spencer has shown , via a simple computer model run on a home computer that this is itself sufficient to explain over 75% of the warming experienced during the 20th century.

Then let him submit his findings to peer review. So, you think it's all to do with the PDO? This is the trouble with all those who are anti the accepted science, you keep moving the goal posts, the only consistency with it is it's down to anything but CO2 (ABCD). When I first got into these debates it's was UHI that was the reason for the warming (but cities and rural areas show the same trend), then we had the satellites not showing any warming (until they were corrected), the it was the HS, then we had various 'gates'. Don't you see, it's ALWAYS ABCD . So, now it's the PDO - OK, that will change in the years to come...

Thus, the PDO itself can potentially explain most of what we popularly call global warming.

And, whilst the anthropogenic explanation for global warming involves a forcing mechanism that can only be computed theoretically, the PDO forcing mechanism (a natural player) is actually observed by satellites.

A recent publication has also made the connection between the PDO and climate change (D.H Douglass and R.S.Knox "Ocean heat content and Earth's radiation imbalance". Physics letters A, 373 (2009): 3296-3300)

I enjoy this forum immensly and have learned and continue to learn a great deal from it, I am also aware of certain posters views and beliefs ..... all valid and I have no problem with any of them posting. But, I do take offence at some of the recent posts aimed at ridiculing some of the information I have offered, clearly without bothering to check up on what has been said.

No ridicule from me, but nice try at playing the persecution card .

I have now read 8 books and countless scientific papers and what myself and others are pointing too is that perhaps (not saying for absolute certainty ... though I am getting closer day by day) is that there is more uncertainty around AGW than some think and contrary to the IPCC consensus, there are natural cyclical explanations for the late 20th century warming that has liitle to nothing to do with greenhouse gas emissions by the human population.

How little? 5%?

I would also state that personally I am happy to curb greenhouse gas emissions and transfer the world economy to a greener footing, this would be brilliant ..... I am just discussing and looking at what has caused the recent warming.

I do have graphs and charts that I should post, but these will have to wait for another time (I travel a lot and do not have access to my home files).

Y.S

But, if CO2 isn't a problem, lets just pour the stuff into the sky regardless.

Edited May 24, 2010 by Devonian

[Thundery wintry showers]

As such it is becoming increasingly clear,that although CO2 is a greenhouse gas, and yes is contributing to the global warming scene, ... it is a minor and not a major player. Furthermore, it is the misguided notion that the climate system is predominatly sensitive (via positive feedback mechanisms) rather than tolerant (via feedback and forcing mecahnisms combined) that is skewing the IPCC global forecast models 'predictions' for the future.

Y.S

There is a problem with the bit in bold (which serves as a conclusion derived from those arguments). Evidence for various natural forcings, and the possibility that they may be contributing to the current warming, casts doubt upon whether CO2 is responsible for most of the warming. What they don't do is make it "increasingly clear" that CO2 is not responsible for most of the warming. For that, we would need to show strong evidence to suggest that they were likely to be bigger players in the warming than CO2.

Uncertainty doesn't imply certainty- you can't have it both ways.

The above said I thought GW's aforementioned jibe was a bit out of order. There is a difference between being an AGW sceptic, or even denier, and saying "I don't care less about our pollution of the environment"- one doesn't always imply the other as there are also other reasons for being concerned about pollution and lack of sustainable resource use.

[Pennine Ten Foot Drifts]

Well thanks for clearing that up GW. Much as I like you,you invariably wind me up terribly with every post as you come across as the High Priest of Righteousness and everyone but yourself is responsible for the catastrophe you are so sure is coming. Actually,most 'warmists' do exactly the same trick,and it does their cause no favours - no favours at all.

How strange is other peoples' perceptions ! Because I would have said it's precisely the opposite to that, the 'warmists' find it infuriating that 'deniers' seem to be utterly unwilling to accept the same 'blame' said 'warmists' have already accepted i.e. we know it's our fault, we're ready to take the punishment, why won't you accept your portion of it ???

[Yorkshiresnows]

Oh, you'd therefore be surprised how much time I spend reading WUWT and the posturings of the Heartland Institute...

It's water vapour changes not cloud cover, water vapour feedback warming - clouds are not water vapour!

Then let him submit his findings to peer review. So, you think it's all to do with the PDO? This is the trouble with all those who are anti the accepted science, you keep moving the goal posts, the only consistency with it is it's down to anything but CO2 (ABCD). When I first got into these debates it's was UHI that was the reason for the warming (but cities and rural areas show the same trend), then we had the satellites not showing any warming (until they were corrected), the it was the HS, then we had various 'gates'. Don't you see, it's ALWAYS ABCD . So, now it's the PDO - OK, that will change in the years to come...

No ridicule from me, but nice try at playing the persecution card .

How little? 5%?

But, if CO2 isn't a problem, lets just pour the stuff into the sky regardless.

What on Earth was the above post about. Absolute nonsence !!!!

You have not understood, nor tried to, anything of what has been stated... nothing at all.

Just so you know a little about Roy Spencer (as you have dished him):

Roy Spencer is a principal research scientist at the University of Alabama. Formerly he was a senior scientist for climate research for climate studies at NASA, he currently leads the US science team for the advanced Microwave Scanning Radiometer for EOS (AMSRE) on NASA's aqua satellite. He is also co-developer of the original satellite method for precise monitoring of global temperatures from earth orbiting staellites and has provided congressional testimony on the subject of global warming. He is also the bestselling author of the book Climate confusion and has published extensively on the subect of weather, climate and global warming.

You might want to take a look at this:

Roy. W Spencer and William D. Braswell, "Potential Biases in cloud feedback diagnosis: A simple model demonstration", Journal of climate 21 (2008); 5624-5628

As for clouds / water vapour you need to understand the relationship between reflective low level cloud effects and refractive high level cloud effects. There is growing evidence that the change in PDO state leads to changes in the overall distribution and cloudiness (low level cover). This then leads to changes in the quantity of absorbed solar irradiation ..... water vapour has around 100 x the power to alter temperature as compared to CO2.

Anyway, you can of course believe what you will.

Y.S

There is a problem with the bit in bold (which serves as a conclusion derived from those arguments). Evidence for various natural forcings, and the possibility that they may be contributing to the current warming, casts doubt upon whether CO2 is responsible for most of the warming. What they don't do is make it "increasingly clear" that CO2 is not responsible for most of the warming. For that, we would need to show strong evidence to suggest that they were likely to be bigger players in the warming than CO2.

Uncertainty doesn't imply certainty- you can't have it both ways.

The above said I thought GW's aforementioned jibe was a bit out of order. There is a difference between being an AGW sceptic, or even denier, and saying "I don't care less about our pollution of the environment"- one doesn't always imply the other as there are also other reasons for being concerned about pollution and lack of sustainable resource use.

Hi TWS,

Yes, accepted. I should have stated " It is becoming increasingly clear to me".

Apologies

Y.S

Edited May 24, 2010 by Yorkshiresnows

[Yorkshiresnows]

But, if CO2 isn't a problem, lets just pour the stuff into the sky regardless.

My apologies, but had to come back to one of your comments in your previous post.

How much Co2 are we flooding into the atmosphere.

Well, lets look at the facts:

Looks pretty dire doesn't it. H'mmmm but then, although we are clearly increasing the amount of CO2 in the atmosphere (and yes, this will be expected to have some warming associated as it is a greenhouse gas), how does this scale relate to the total percentage of gases that make up the atmosphere.

Well as of 2008, atmospheric CO2 was approaching 390 ppm by volume, or about 39 molecules of Co2 per 100,000 molecules of air and around 40% more than believed to be the case pre-industrialisation (270 ppm).

Al Gore stated that you could average the amount of Co2 being pumped into the air every day would be in the region of 70 million tonnes ..... sounds brutal ...... but,

If this statistic is correct it would take 5 years of these daily greenhouse gas emissions to add just one molecule of CO2 to every 100,000 molecules of air in the atmosphere.

Thus, even though CO2 is a trace gas, it still takes a long time of our burning of fossil fuels to impact its atmospheric concentration substantially.

As a fraction of the atmosphere and looking back from 1955 to 2010 we will have increased the overall atmospheric value from around 0.0003 to around 0.0004. (The graph I want to show is not behaving, so will pdf and input as picture later).

So, either CO2 is capable of being a most potent greenhouse gas and regulates world temperatures, or, something else is at work.

Y.S

[Devonian]

My apologies, but had to come back to one of your comments in your previous post.

How much Co2 are we flooding into the atmosphere.

Well, lets look at the facts:

...

Y.S

It's from ~.03% to ~.04%.

Oh, and the argument that because something is in trace concentrations it isn't significant has been shown over and over again to be wrong. But, there are endless highly poisonous substances you can partake of in similar concentrations if you don't believe me

No, CO2 is a ghg that if doubled in concentration will cause a warming effect of about 1C. And, yes, that isn't very much on it's own. But, this observer of all things atmospheric finds it hard to see how 1, a atmosphere 1C warmer wont hold more water vapour and 2, how the changes cause by 1C warming (ice melt) wont reduce the Earth's albedo. So, I think we'll see feedbak warming - but don't try and paint me as a alarmist or a catastropists - I see 2-4C warming which is serious, should be stopped and will damage the planet. Sadly (from my POV) 'sceptics' have won the arguement atm and we are going to do little (as a species) about curbing ghgs and we're probably going to add at least another decade of unlimited emissions. Great...

Btw, yes, I know the PDO is the current ABCD but, sorry, I've seen it all before and, like every other ABCD I expect this PDO talk will pass and those who wont accept the science will move on to the next get out of reality quibble.

[jethro]

No, CO2 is a ghg that if doubled in concentration will cause a warming effect of about 1C. And, yes, that isn't very much on it's own. But, this observer of all things atmospheric finds it hard to see how 1, a atmosphere 1C warmer wont hold more water vapour .....

Doesn't that then bring us back to the great unknown impact of clouds?

[Yorkshiresnows]

Doesn't that then bring us back to the great unknown impact of clouds?

Exactly.

And, Devonian, the warming of a doubling of CO2 to around 540 ppm is accepted to result in a 1 degree C rise in the upper atmosphere. It is further accepted that at the ground this would relate to less than that (around 0.5 to 0.6 degrees C).

So, it all comes round to the forcings and feedbacks. Is the climate system sensitive or resilient. What other factors could be responsible?

The PDO is a fairly new concept ..... well, not new, but a greater understanding of its impacts are beginning to surface. Of course there are others such as solar, the AO, NAD and AMO. New science is emerging all the time. Just a few years ago most would not take the notion of a relationship between solar cycels and Northern hemisphere temperatures (probably global affects) that seriously. Its certainly under consideration now.

Surely we can at least explore the possibility that the changes in states of these major oceanic / atmospheric players could impact global climate, is it that far-fetched when we know that El-nino and La Nina both warm and cool the climate almost immediately. If so, then why is the idea that longer term 30 year period or more changes in the PDO and other natural cycles could not impact on global temperatures ....... what effects do these have on global cloud cover for instance. A 1% or 2% change in cloud cover could have caused all of the climate change we saw during the 20th Century, and such a small change would have been impossible to detect.

I've pinched the below from Mr Spencer's blog, but basically these show the pre-1940 warming coinciding with the positive phase of the PDO; then, a slight cooling until the late 1970s coincided with a negative phase of the PDO; and finally, the warming since the 1970s has once again coincided with the positive phase of the PDO.

Mr Spencer then asked a simple question: What if this known mode of natural climate variability (the PDO) caused a small fluctuation in global-average cloud cover?

Without regurgitating all of his work, I would recommend a visit to his blog and possible purchase of the paper back edition of 'The Great Global Warming Blunder' in which his work is discussed in simplistic detail (or even reference his publications). Even if you do not believe his views are correct, he has generated a simplistic model and used actual satellite measurements to almost exactly replicate the 20th century temperature changes !!

Y.S

[Devonian]

Exactly.

And, Devonian, the warming of a doubling of CO2 to around 540 ppm is accepted to result in a 1 degree C rise in the upper atmosphere. It is further accepted that at the ground this would relate to less than that (around 0.5 to 0.6 degrees C).

So, it all comes round to the forcings and feedbacks. Is the climate system sensitive or resilient. What other factors could be responsible?

The PDO is a fairly new concept ..... well, not new, but a greater understanding of its impacts are beginning to surface. Of course there are others such as solar, the AO, NAD and AMO. New science is emerging all the time. Just a few years ago most would not take the notion of a relationship between solar cycels and Northern hemisphere temperatures (probably global affects) that seriously. Its certainly under consideration now.

Surely we can at least explore the possibility that the changes in states of these major oceanic / atmospheric players could impact global climate, is it that far-fetched when we know that El-nino and La Nina both warm and cool the climate almost immediately. If so, then why is the idea that longer term 30 year period or more changes in the PDO and other natural cycles could not impact on global temperatures ....... what effects do these have on global cloud cover for instance. A 1% or 2% change in cloud cover could have caused all of the climate change we saw during the 20th Century, and such a small change would have been impossible to detect.

I've pinched the below from Mr Spencer's blog, but basically these show the pre-1940 warming coinciding with the positive phase of the PDO; then, a slight cooling until the late 1970s coincided with a negative phase of the PDO; and finally, the warming since the 1970s has once again coincided with the positive phase of the PDO.

But there is no NET change in the PDO. So, you're saying something that, essentially, hasn't change can cause a long term change in temperature. Sorry, but looking at the graph I see one rising and one fluctuating - not changing. So, how does a none change cause a change?

Mr Spencer then asked a simple question: What if this known mode of natural climate variability (the PDO) caused a small fluctuation in global-average cloud cover?

Again, why are temperatures higher when the PDO is no higher than where temperatures were lower?

Without regurgitating all of his work, I would recommend a visit to his blog and possible purchase of the paper back edition of 'The Great Global Warming Blunder' in which his work is discussed in simplistic detail (or even reference his publications). Even if you do not believe his views are correct, he has generated a simplistic model and used actual satellite measurements to almost exactly replicate the 20th century temperature changes !!

Y.S

Some quick points.

1, I don't dispute there is a way of crudely classiflying climate we can call the PDO.

2, the PDO (like ENSO) is a internal part of the climate system - it's energy distributive not addative. As such saying it has a net effect more than zero (that long term it changes global temperature) is a bit like saying it's the piston that drive a engine - it's not it's the energy input to the system that drives both climate and an engine.

3, The input to the climate system is almost all solar.

4, But the greenhouse effect is a bit like sending some of the unburt fuel that escapes in an engines exhaust back into the engine = more energy in the system.

5, so the gh effect also 'forces' climate like solar output does - in a small way (a few degrees out of several hundred). Solar and GH effect - that's all (atm).

6, So why, how, can the climate be forced to warm long term, is the question I ask.

7, clouds. If these are unknown then they ARE unknown.

8, Btw, who says the warming figure is for the upper atmosphere?

Edited May 25, 2010 by Devonian

[Yorkshiresnows]

But there is no NET change in the PDO. So, you're saying something that, essentially, hasn't change can cause a long term change in temperature. Sorry, but looking at the graph I see one rising and one fluctuating - not changing. So, how does a none change cause a change?

Again, why are temperatures higher when the PDO is no higher than where temperatures were lower?

Some quick points.

1, I don't dispute there is a way of crudely classiflying climate we can call the PDO.

2, the PDO (like ENSO) is a internal part of the climate system - it's energy distributive not addative. As such saying it has a net effect more than zero (that long term it changes global temperature) is a bit like saying it's the piston that drive a engine - it's not it's the energy input to the system that drives both climate and an engine.

3, The input to the climate system is almost all solar.

4, But the greenhouse effect is a bit like sending some of the unburt fuel that escapes in an engines exhaust back into the engine = more energy in the system.

5, so the gh effect also 'forces' climate like solar output does - in a small way (a few degrees out of several hundred). Solar and GH effect - that's all (atm).

6, So why, how, can the climate be forced to warm long term, is the question I ask.

7, clouds. If these are unknown then they ARE unknown.

8, Btw, who says the warming figure is for the upper atmosphere?

Give up,

Last one from me on this subject, you clearly are unable to grasp what I was inferring, but I suspect most of your posts are just wind-up efforts anyway as they are so silly to the point of being just plain stupid.

The argument is that the PDO can affect global cloudiness (as well as predominance of El Nino / La Nina conditions). If it does have an impact on low cloud cover, then there will be a net reduction in global temperature due to a reduced rate of solar absorption at the Earth's surface.

There are now several scientific papers (and blogs) you can visit that are suggesting just that .... one being Roy Spencer (go and have alook, huis blog contains a bevy of publications and you can see the peer reviewed literature for yourself !!).

His model has actual satellite data (that's proven measurements) suggesting that such a link occurs and has produced a model that could (repeat could) explain most of the 20th century warming without relying on a greenhouse gas model (for which the methodology relies entirely on computed feedback mechanisms that are not proved).

Y.S

[Devonian]

Give up,

Last one from me on this subject, you clearly are unable to grasp what I was inferring, but I suspect most of your posts are just wind-up efforts anyway as they are so silly to the point of being just plain stupid.

I've put the accepted science forward. What, if I'd gone, I'd have leanrt at uni or the Met Office.

I don't see the need for you to call me stupid or (and it's a worse slurr tbh) imply I'm am on a wind up. I reply to people's posts, I can do without such replies for my trouble. This is a debate, we both have differing views, I don't accept yours and I put forward my case as to why. Address my points, don't resort to ad hom.

The argument is that the PDO can affect global cloudiness (as well as predominance of El Nino / La Nina conditions). If it does have an impact on low cloud cover, then there will be a net reduction in global temperature due to a reduced rate of solar absorption at the Earth's surface.

Buit, how can this happen if the PDO has no trend? A trendless indicator cause a trend in temperature? How? Why wasn't temp as high last time the PDO was as it is now. No insults, why?

There are now several scientific papers (and blogs) you can visit that are suggesting just that .... one being Roy Spencer (go and have alook, huis blog contains a bevy of publications and you can see the peer reviewed literature for yourself !!).

His model has actual satellite data (that's proven measurements) suggesting that such a link occurs and has produced a model that could (repeat could) explain most of the 20th century warming without relying on a greenhouse gas model (for which the methodology relies entirely on computed feedback mechanisms that are not proved).

Y.S

No it does not. It relies on accepted, known, shown physics. Not proven, but certainly not disproven.

Edited May 25, 2010 by Devonian

[Gray-Wolf]

As I hope to have made plain I do not see human interference in climate as the only driver.

I just wonder where the school of thought that 'natural' and not 'human' drove 20th century warming draw the line for when 'human interference' does' start to have an impact?

With CO2 it looks like this year will see the 400ppm level broken and we see no signs of global outputs reducing any time soon, do the 'natural cycle' folk see any role for CO2 in future climate change (we see some relation in past warming/cooling episodes so will this 'relationship' still hold with the current warming?).

Do the folk who assign all of the 20th century warming to 'natural cycles' believe that mans impacts (land use/CO2/Deforestation etc.) will eventually start to drive change or do they think that man could never impact climate?

[Admiral_Bobski]

Something very interesting occurs to me about this graph. The negative phase up to around 1920 was nowhere near as pronounced as the negative phase between 1940 and 1970.

During a negative phase the ocean is effectively absorbing heat, which is later released during a positive phase (simplified, but that's the general gist).

Now, the PDO was particularly negative around 1950-1955/6, which was when the Sun was ramping up to its highest maximum of sunspot activity.

So, there was markedly high sunspot activity (which generally correlates to increased insolation) at a time when the oceans were absorbing a great deal of energy.

Post-1970 we see a return to positive PDO, and suddenly temperatures start to rise dramatically.

You are quite right, Devonian, that the PDO does not - in and of itself - create more heat. But we need to look at the bigger picture, compare the positive and negative phases with other phases and see how and where they coincide with increases in incoming radiation.

This PDO data set has been incorporated into the LI, as have the sunspot numbers over the same period. These figures, along with some others, generate the LI output. What I have just described above is incorporated into the LI, but has perhaps not been explicitly laid out as I have just done.

Thoughts?

CB

[VillagePlank]

Do the folk who assign all of the 20th century warming to 'natural cycles' believe that mans impacts (land use/CO2/Deforestation etc.) will eventually start to drive change or do they think that man could never impact climate?

Is there a third, fourth, fifth, sixth (...) option? Just wondering ....