General Climate Change

[VillagePlank]

Those forcing figures are for the change in atmosphere conc seen, why would you divide them in the way you do? Atmosphere conc has risen, due to our activities, by ~30% not 5%.

We're not going to have to go back to basics on the carbon cycle again are we?

It's perfectly possible that I've misread the source. The link is in my previous post, and here is the extract:

Manmade CO2 emissions are much smaller than natural emissions. Consumption of vegetation by animals & microbes accounts for about 220 gigatonnes of CO2 per year. Respiration by vegetation emits around 220 gigatonnes. The ocean releases about 332 gigatonnes. In contrast, when you combine the effect of fossil fuel burning and changes in land use, human CO2 emissions are only around 29 gigatonnes per year. However, natural CO2 emissions (from the ocean and vegetation) are balanced by natural absorptions (again by the ocean and vegetation). Land plants absorb about 450 gigatonnes of CO2 per year and the ocean absorbs about 338 gigatonnes. This keeps atmospheric CO2 levels in rough balance. Human CO2 emissions upsets the natural balance.

TBH, I can't see how I can misread 'emissions' for 'concentrations' but maybe I've missed something. I suppose one might argue that I should deduct the 220gt of consumption ....

... which gives 8%, which therefore, using the above analysis gives the answer 11.4% difference due to anthropogenic CO2 forcing.

The normal caveats as mentioned above apply, and, of course, you should be mindful that this only directly attributable effect of manmade CO₂ - it doesn't include reduction in albedo, nor black soot, or other factors.

(EDIT: 11.4% is well over one million square kilometres!!)

(EDIT2: Still something (slightly) wrong, here: I will look for another source - anyone got one handy?)

Edited June 3, 2010 by VillagePlank

[VillagePlank]

I don't suppose any of the University students who loiter in here, instead of studying , can get the figures from Keeling et al., 1995 ?

Pretty please? Particularly the airborne fraction figure.

(Serves me right for using blogs as a source <_< )

Edited June 3, 2010 by VillagePlank

[jethro]

You are an absolute star VP, that is precisely the kind of answer I've been looking for. Thank you soooooo much.

[Thundery wintry showers]

Annual mole fraction increases (ppm) in CO₂ are mostly between 1.50 and 2.00 over the last 30 years and raw values have gone up from approximately 338 to 386, if I'm reading the figures correctly, since 1980. This is from the following source: http://www.esrl.noaa.gov/gmd/ccgg/trends/#global_data I can't find any mention of the percentage of the increase that is deemed to be due to human activities though.

But put in simple terms, if human activity has contributed to the rise in global temperatures over that period it's extremely likely that human activities will also have contributed to sea ice melt in view of the large inverse correlation between temperatures and sea ice (-0.76) mentioned by VillagePlank. The question then moves over to how much of the melt can be explained by anthropogenic forcings.

[VillagePlank]

...in view of the large inverse correlation between temperatures and sea ice (-0.76) mentioned by VillagePlank. The question then moves over to how much of the melt can be explained by anthropogenic forcings.

Yes, I limited the answer to the CO₂ only. Clearly, we get up to an awful lot more than just pump CO₂ out. Without even looking at the feedbacks (or forwards) we'd need to include hydrocarbons, aerosols, black soot etc etc.

But, on this analysis, the limit with respect to a linear relationship to temperature is 76% - the correlation - which means 24% of it is either non-linearly related (likely) or something else entirely.

It's never quite simple.

Edited June 3, 2010 by VillagePlank

[VillagePlank]

You are an absolute star VP, that is precisely the kind of answer I've been looking for. Thank you soooooo much.

It might not be right - but it's a starting point, and hopefully everyone can add something to this so we can, by pertubation, get to a realistic figure given the data we have to hand.

<_<

[sunny starry skies]

Ah, VP, I think the hangover may have got in the way of your normally excellent numerical skills. I think you're confusing total emissions (your 552GT) with the balance between emissions and absorptions which defines the total concentration and resulting changes. Much of the 552GT is absorbed naturally - and pre-industrial times the carbon cycle was approximately in balance. Anthropogenic emissions are what has produced the great majority (ie nearly all) of the increase in concentration, as the carbon sinks have been unable to keep up with the new carbon sources. Given that this increase in atmospheric CO2 has driven (dominantly, with a small early 20th Century solar component) the temperature rise, and that the Arctic temperature rise is particularly susceptible to enhanced GHGs, most of the 20th/21st Century decline in sea ice is surely attributable to the increase in CO2. [i know you disagree with me on the relative merits of CO2/solar, but that's not for now]. Certainly the value of 5% included in the warming in your calculation should be rather closer to 100%, unless you doubt that the change from 280ppm to 380ppm was nearly all anthropogenic [which I don't think you do!]. EDIT: Just looking back at your calculations, you show a 76% correlation between temperature and sea ice, but when you multiply the 76% by your 2.5%, you're determining how much of that 76% is due to CO2 (how good the relationship is), not how much larger the sea ice cap would be if you removed the CO2. And so if we go on your IPCC figure of 51% of the energy imbalance is due to CO2, approximately all of which is due to anthropogenic input, then CO2 would be responsible directly for ~38% of the relationship between ice and temperature?

YS - we know Greenland was warmer in the Medieval than the early 20th Century, ditto Iceland. But there has been a lot of warming since then (!). And do you know that what you quote Brian Fagan it's not the original source? Most of the assertions you quote from Fagan are not easily supported by evidence, and quotes from sagas, often written >200 years after the events are notoriously unreliable. Fagan is also at liberty in his book to interpret the evidence in which way he will, but it does not make him the last word on the subject. Hence we can say that it was probably warmer/better weather in Norse times, but we cannot say by how much, or assess the veracity of statements about crops etc, unless we have corroborating historical, or more importantly, archaeological data. Do you have original sources for your quotes? The reason I got at you was because you were making comments about 'no ice', and then 'ice covering settlements', which were wrong. I'm not disputing the presence of the MWP in Greenland, but will happily dispute the climatic extinction of the Norse, for which there is no direct evidence. sss

Edited June 3, 2010 by sunny starry skies

[Yorkshiresnows]

Ah, VP, I think the hangover may have got in the way of your normally excellent numerical skills. I think you're confusing total emissions (your 552GT) with the balance between emissions and absorptions which defines the total concentration and resulting changes. Much of the 552GT is absorbed naturally - and pre-industrial times the carbon cycle was approximately in balance. Anthropogenic emissions are what has produced the great majority (ie nearly all) of the increase in concentration, as the carbon sinks have been unable to keep up with the new carbon sources. Given that this increase in atmospheric CO2 has driven (dominantly, with a small early 20th Century solar component) the temperature rise, and that the Arctic temperature rise is particularly susceptible to enhanced GHGs, most of the 20th/21st Century decline in sea ice is surely attributable to the increase in CO2. [i know you disagree with me on the relative merits of CO2/solar, but that's not for now]. Certainly the value of 5% included in the warming in your calculation should be rather closer to 100%, unless you doubt that the change from 280ppm to 380ppm was nearly all anthropogenic [which I don't think you do!]. EDIT: Just looking back at your calculations, you show a 76% correlation between temperature and sea ice, but when you multiply the 76% by your 2.5%, you're determining how much of that 76% is due to CO2 (how good the relationship is), not how much larger the sea ice cap would be if you removed the CO2. And so if we go on your IPCC figure of 51% of the energy imbalance is due to CO2, approximately all of which is due to anthropogenic input, then CO2 would be responsible directly for ~38% of the relationship between ice and temperature?

YS - we know Greenland was warmer in the Medieval than the early 20th Century, ditto Iceland. But there has been a lot of warming since then (!). And do you know that what you quote Brian Fagan it's not the original source? Most of the assertions you quote from Fagan are not easily supported by evidence, and quotes from sagas, often written >200 years after the events are notoriously unreliable. Fagan is also at liberty in his book to interpret the evidence in which way he will, but it does not make him the last word on the subject. Hence we can say that it was probably warmer/better weather in Norse times, but we cannot say by how much, or assess the veracity of statements about crops etc, unless we have corroborating historical, or more importantly, archaeological data. Do you have original sources for your quotes? The reason I got at you was because you were making comments about 'no ice', and then 'ice covering settlements', which were wrong. I'm not disputing the presence of the MWP in Greenland, but will happily dispute the climatic extinction of the Norse, for which there is no direct evidence. sss

Clearly the books and references that you use are superior and more accurate than all others quoted.

Enough now, again the point of the post was missed and is now so contaminated with silly nit-picking that we must move on.

My father was a farmer (Experimental horticulturist) and I can assure you that farming records going back to the medieval period do exist and are accurately quoted by Fagan.

If you wish to dispute this, then you go right ahead. I've seen nothing but praise for one of the most wonderfull historical accounts of how climate made history. Excellent reviews from no less than Scientific American and New Scientist.

Still it must all be a load of old tosh .... if you say so !!

Cobblers

Did you read the paper on the Indo-Pacific warm pool by any chance ?

Y.S

[Guest North Sea Snow Convection]

I'm sorry NSSC but you are incorrect. I have clearly clarified my views at least twice on this forum, along with many others, in two dedicated threads.

http://forum.netweat...ce/page__st__17

http://forum.netweat...-in-1-sentence/

The first of these obviously offers more scope for detail, in which I leave the option to others to pigeon hole me, personally preferring the tag of "questioner".

As far as this particular point in time and my recent posts I have had difficulties trying to make folk understand I am asking this question not from a sceptic viewpoint but from a searching for information point. I have stipulated this as the replies I was receiving were all aimed at beating the sceptic's views rather than answering my question.

When it comes to sceptic/pro/denier and all the other daft tags people get afflicted with, I've always argued for no definitions as to my mind, they all lead to needless and pointless conflict. There are no sides or camps in this debate for me, we're all just individuals with a mutual interest in the climate and future of this planet; to me that seems we all have more in common with each other than the sometimes petty tit for tat would lead folk to believe. If we didn't all share a mutual concern for this planet, we wouldn't be here and that to me is cause for celebration and hope.

Have I amended my position? Well having read through "My stance" written on here back in February 2008 I have to say no, I haven't. I was a questioner then, I'm a questioner now; as you can see I've spent the last however many days asking questions.

Has being a Moderator changed my views? No it hasn't. Being a Moderator simply means assisting everyone to get their chance to have their say, without the fear of intimidation and trying to ensure the debates remain polite and respectful. If someone doesn't comply with that, regardless of their views on this subject, I'll step in. Equally, just because I may fundamentally agree with the gist of someone's argument doesn't mean I'll stand back and let them make it in a rude and hostile manner. Can't get more even handed than that, can I?

GW: you still seem to be approaching this from a "convincing me we're to blame" point of view. I really cannot say any clearer than I've already said that, that is not my approach to this question. I'm not questioning the validity of the AGW theory.

I did say, Jethro, that it was just an observation....

I have not yet had time to read both links (and for some reason can't open the second one anyway) but the first one which I have read (and which I am in a lot of agreement with) is, still imo, a shift in sentiment from your current one. Or rather, the other way around , the shift has occured since then. Perhaps also, in retrospect, having posted late yesterday, 'sentiment' is the word I should have initially used.

You are naturally entitled to that, it is not criticism, just, as as I tried to say, an observation which can be deemed wrong if wished.

Regarding the rest of what you said - if it wasn't for the styles of posting that are adopted by individuals then I dare say that more common ground might be found by both sides of the debate and less of a 'them and us' regrettable theme would prevail. I am not, and have never been, personally, interested in 'winning' any 'armchair debating', which is the sort of competitive alpha arena that some approach these threads with but I will continue to question the validity of the AGW theory, at the very least in terms of its proposed extent, and will continue to question the emphaticness that some assuage to in this regard in certain quarters. And despite the brickbats that always follow for doing this.

SSS - everyone is 'speculating' about the causes and effects of climate movements. Supposition indeed extends to all ideas about what drives the climate movements but the difference is that some of us who are much less convinced about AGW, aren't trying to present any suppositions about natural drivers as something cut and dried, absolute and emphatic and crucially, then at the same time derogate anyone who differs. So if I suggest that AGW is based on supposition about the existence of positive feedbacks being available to enhance warming it is only because I am reminding people such as you that this works both ways.

As I said above, it is posting styles that become the main bone of contention rather than the differing ideas themselves.

Edited June 3, 2010 by North Sea Snow Convection

[laserguy]

http://www.newsweek....in-science.html

This is alright,the final paragraph of which has particular resonance for me and I suspect,for all those of a similar persuasion. Whilst the bickering goes relentlessly on,here and everywhere about the validity of the extremely rocky science of AGW,we encroach by the minute the real (and very tiny snapshot) state of things to come. Fretting over "AGW" is comparable to a man in his death throes from some dreadful rampant tumour being more concerned with treating the sniffle he's just picked up. The tragedy here is that AGW is still nothing more than a hypothesis/theory. See y'all on the other side. Gawd I wish it was October.....

[Admiral_Bobski]

I'm assuming, from the posts of the last 24 hours, that we're allowing the Milankovitch misconception to stand? Nobody seems interested in getting to the bottom of the matter.

Another thing that springs to mind is that it is incorrect to say that ENSO has no net effect on temperatures.

If we accept that a negative ENSO tends to cool the globe (draws heat into the ocean) and a positive ENSO tends to warm the globe (expels heat from the ocean) then, superficially, it seems that ENSO's net effect is zero.

However, if we have a negative ENSO during a period of higher insolation then there may be two effects: firstly, the globe may not cool as much as it would with lower insolation and, secondly, the oceans may draw in more warmth.

If the next positive ENSO period then occurs during a period of higher insolation then you have the dual effect of higher insolation plus more heat coming from the ocean.

I do believe, if I'm not very much mistaken, that this process would introduce some kind of...um...what's the word?.... Lag, is it?

(Just to clarify, ENSO's net effect is zero if all else remains equal which, as is quite obvious in the real world, is never the case.)

Edited June 3, 2010 by Captain_Bobski

[Yorkshiresnows]

Hi All,

Some good discussions on here today and interesting points made by a few.

I know that the issue of clouds is quite controversial and I (as well as others) have posted on the bizare point that the IPCC only assumes a positive (enhancing) effect of increased water vapour as a feedback of CO2 induced warming ....... yet ignores the very real possibility that at least a portion of this increased water vapour may turn to clouds and act as a negative feedback ... cancelling out some of the warming.

I've alos posted a lot on Peter taylor's work as well as Roy Spencer and this has proved particularly controversial.

Anyway, Dr Spencer has an interesting addition to his current blog on this issue:

http://www.drroyspencer.com/

Y.S

[Thundery wintry showers]

http://www.newsweek....in-science.html

This is alright,the final paragraph of which has particular resonance for me and I suspect,for all those of a similar persuasion. Whilst the bickering goes relentlessly on,here and everywhere about the validity of the extremely rocky science of AGW,we encroach by the minute the real (and very tiny snapshot) state of things to come. Fretting over "AGW" is comparable to a man in his death throes from some dreadful rampant tumour being more concerned with treating the sniffle he's just picked up. The tragedy here is that AGW is still nothing more than a hypothesis/theory. See y'all on the other side. Gawd I wish it was October.....

An interesting link indeed. I think, though, that the main thing undermining the credibility of the AGW cause is when politics gets involved. The science may not be perfect at achieving a balanced overview but it's pretty good, but when politics comes into play there's a desire to express everything in black and white rather than in probabilities and varying shades of grey. Also, in political discussions debate is often stifled as you have to "play the party line" or be kicked out.

The ethos of the last paragraph is similar to my own sentiments, and I say that as someone who believes in AGW.

Regarding cloud feedbacks it is well established that these are uncertain- uncertain both ways, that is.

[sunny starry skies]

LG - http://climateprogress.org/2010/05/31/newsweeks-stefan-theil-uncertain-science-climate-denier/ Always best to see both sides, and here we see the Newsweek article exposed as rubbish, including the last paragraph.

YS - you don't get it (why am I not surprised)... how do you know your source was right? You should read up on how to verify historical data. It's a nice book (I never said it wasn't), but that doesn't automatically make everything in it correct. I'd say my sources are more current than yours, as they are people actively working on Norse Greenland, not somebody who's written a much wider-ranging book of which Greenland is only a small part. I certainly don't need to ask my dad! Farming records in Europe go back to the Medieval, yes, but not in Greenland...

Speaking of Roy Spencer:

http://tamino.wordpress.com/2008/07/28/spencers-folly/ (in 3 parts)

http://scienceblogs.com/deltoid/2010/01/roy_spencer_hides_the_increase.php

http://scienceblogs.com/deltoid/2008/05/roy_spencer_says_that_if_you_d.php

http://scienceblogs.com/stoat/2008/01/spencer_is_totally_off_his_roc.php

http://www.realclimate.org/index.php/archives/2008/05/how-to-cook-a-graph-in-three-easy-lessons/

yikes! Some, ah, "interesting" theories there...

C-Bob, how does an internal redistribution of energy lead to a radiative imbalance? By definition, ENSO causes temporary warming and cooling (as observed), but cannot add heat to the system. You're speculating, without evidence (lots of 'ifs'). And if Ruddiman's right, Loutre is wrong on his 'long interstadial' hypothesis with decoupling from CO2, which is beside the point as our forcing has changed the picture entirely, at least in the short term - e.g.: Cochelin et al (2006), Climatic Change.

sss

[jethro]

I did say, Jethro, that it was just an observation....

I have not yet had time to read both links (and for some reason can't open the second one anyway) but the first one which I have read (and which I am in a lot of agreement with) is, still imo, a shift in sentiment from your current one. Or rather, the other way around , the shift has occured since then. Perhaps also, in retrospect, having posted late yesterday, 'sentiment' is the word I should have initially used.

You are naturally entitled to that, it is not criticism, just, as as I tried to say, an observation which can be deemed wrong if wished.

Well, what can I say, I know what I believe and think about things, I can explain as honestly as I possibly can but if that is then interpretted as something else by someone else, so be it. Ironically, that "What is my stance" thread was started as there had been so much confusion about where people stood in this debate.

Perhaps there were some expectations from some quarters that when I became a MOD, I'd favour one side of this debate over the other, perhaps supporting my own views or even perhaps champion the few female posters; I stick with how I deal with day to day life and that's as fair minded as possible on a meritocracy basis.

EDIT: If I confuse folk now isn't that a clear indication that I do try to put my own views to one side and be as fair minded as I can be? Isn't that a good thing?

[Admiral_Bobski]

C-Bob, how does an internal redistribution of energy lead to a radiative imbalance? By definition, ENSO causes temporary warming and cooling (as observed), but cannot add heat to the system. You're speculating, without evidence (lots of 'ifs'). And if Ruddiman's right, Loutre is wrong on his 'long interstadial' hypothesis with decoupling from CO2, which is beside the point as our forcing has changed the picture entirely, at least in the short term - e.g.: Cochelin et al (2006), Climatic Change.

sss

Okay, I was not specific enough in my last post, so let me rephrase.

ENSO's net effect should be zero given enough time. We have been talking pretty much exclusively about the effect of ENSO on global temperatures during the "global warming" period.

Let's say, for the sake of argument, that the period we have been discussing is 150 years. Is 150 years long enough for ENSO's effects to balance out at zero?

I accept that we have been through a number of ups and downs in the ENSO cycle, but quite clearly these ups and downs have not all been equal, not just in the magnitude of the peaks and troughs but in terms of the varying heat within, and entering, the system at any given point.

So ENSO's effect over the past 150, 200 or 1000 years does not have a net value of zero.

This is patently not "speculating without evidence" but rather an absolutely fundamental truth of the nature of ENSO - it is the way it must be.

Do you agree with this?

Actually - if I may further clarify - ENSO does add heat to the system if we're talking about the atmosphere! Since we do not generally take the total heat content of the oceans into account, any heat which comes from the ocean should be treated as a heat input into the (atmospheric) system.

[Yorkshiresnows]

LG - http://climateprogre...climate-denier/ Always best to see both sides, and here we see the Newsweek article exposed as rubbish, including the last paragraph.

YS - you don't get it (why am I not surprised)... how do you know your source was right? You should read up on how to verify historical data. It's a nice book (I never said it wasn't), but that doesn't automatically make everything in it correct. I'd say my sources are more current than yours, as they are people actively working on Norse Greenland, not somebody who's written a much wider-ranging book of which Greenland is only a small part. I certainly don't need to ask my dad! Farming records in Europe go back to the Medieval, yes, but not in Greenland...

Speaking of Roy Spencer:

http://tamino.wordpr...spencers-folly/ (in 3 parts)

http://scienceblogs....he_increase.php

http://scienceblogs....at_if_you_d.php

http://scienceblogs....off_his_roc.php

http://www.realclima...e-easy-lessons/

yikes! Some, ah, "interesting" theories there...

C-Bob, how does an internal redistribution of energy lead to a radiative imbalance? By definition, ENSO causes temporary warming and cooling (as observed), but cannot add heat to the system. You're speculating, without evidence (lots of 'ifs'). And if Ruddiman's right, Loutre is wrong on his 'long interstadial' hypothesis with decoupling from CO2, which is beside the point as our forcing has changed the picture entirely, at least in the short term - e.g.: Cochelin et al (2006), Climatic Change.

sss

H'mmmm lets see ..... oh I get it ... your right and I must be wrong because ...... you say so.

Your are joking, making yourself look plain silly and going nowhere.

My dad is dead thanks but again you missed the point of what I was getting at. Your sources tell you what exactly ...... and how are they prooving me wrong

The fact that you wish to marginalise the medieval warm period / Little ice-age in the face of massive overwhelming data (proxy data from around the world and historical fact) is quite beyond me ...... I guess its that they are an obvious problem to explain in regards to the current view on AGW and past cycles (your not related to Michael mann are you ?).

Anyway, folk reading these increasingly pointless posts (that I somehow cannot stop myself replying to) must wonder what on earth this place is all about. I would urge reading up on all sides of the arguments and coming to your own peaceful conclusion ... whatever that may be.

Meanwhile, the clock is ticking. El Nino has now completely collapsed with La Nina conditions likely before the end of the year and with no overall warming for the past 10 years that does not compute with IPCC forecasts....... but of course natural cycles have no part to play !!!!

Y.S

[sunny starry skies]

Okay, I was not specific enough in my last post, so let me rephrase.

ENSO's net effect should be zero given enough time. We have been talking pretty much exclusively about the effect of ENSO on global temperatures during the "global warming" period.

Let's say, for the sake of argument, that the period we have been discussing is 150 years. Is 150 years long enough for ENSO's effects to balance out at zero?

I accept that we have been through a number of ups and downs in the ENSO cycle, but quite clearly these ups and downs have not all been equal, not just in the magnitude of the peaks and troughs but in terms of the varying heat within, and entering, the system at any given point.

So ENSO's effect over the past 150, 200 or 1000 years does not have a net value of zero.

This is patently not "speculating without evidence" but rather an absolutely fundamental truth of the nature of ENSO - it is the way it must be.

Do you agree with this?

Actually - if I may further clarify - ENSO does add heat to the system if we're talking about the atmosphere! Since we do not generally take the total heat content of the oceans into account, any heat which comes from the ocean should be treated as a heat input into the (atmospheric) system.

C-Bob, have a read of:

http://www.skeptical...bal-warming.htm

You'll see the relative amounts of heat injected into the atmosphere and ocean since 1950. The rest of teh article is instructive reading too. Most anthropogenic warming is going into the ocean, only a little is warming the atmosphere. ENSO does not do that. You're still not showing me a long-term trend in ENSO either, only suggesting what might be, and so no I don't agree with you.

http://www.skeptical...ming-going.html

An interesting article for those that doubt water vapour feedbacks here (Dessler and Sherwood 2009, in Science), but should be freely available from here:

http://geotest.tamu....6/dessler09.pdf

sss

YS, we agree that in Greenland the MWP was relatively warm. We disagree on ice covering settlements in the LIA, and on a lack of sea ice in the MWP. Both of which you stated, without providing evidence. I provided evidence for the opposite. We also disagree on how to interpret historical records. I'll give you a clue - how do you know they are historical 'facts', especially when they were not written contemporaneously, or pertain to another region of the world? And with respect, you brought up your father, not me.

And thanks for putting words into my mouth, I have no wish to see the MWP 'disappear', neither does any other researcher. It was a perfectly sound event if you're a European or a Medieval Greenlander. But that does not mean it's a global event. And I'd put a summary of >1000 records from around the globe over your romantic assertions on that one. Remind me again, just exactly what the climatic significance of a strong global MWP is, by the way? High climate sensitivity in the future, or low climate sensitivity? I know which one I'd prefer. Low climate sensitivity, as shown in the global 'hockey stick', is rather prefereable over high sensitivity, given how much we have perturbed the energy balance of the Earth. But you seem to wish to believe that the MWP was global, and somehow that's a good thing in the context of global warming? :ph34r:

You also don't realise that the MWP has nothing to do with the fundamentals of AGW theory...

No global warming in 10 years is rubbish and you know it. Apart from my 2nd link above, look at:

http://woodfortrees.org/plot/hadcrut3vgl/from:2000/plot/hadcrut3vgl/from:2000/trend/plot/gistemp/from:2000/trend/plot/gistemp/from:2000/plot/uah/from:2000/plot/uah/from:2000/trend

See any downward slopes?

And yet again I'll post to this excellent guide to the 2000s by Tamino:

http://tamino.wordpress.com/2009/12/07/riddle-me-this/

and to:

http://tamino.wordpress.com/2009/12/15/how-long/

See any spectacular deviations from our warming trend? [and I'd reiterate that despite the insults flying at me here I'd really like to see that trend going the other way...]

Edited June 3, 2010 by sunny starry skies

[Thundery wintry showers]

LG - http://climateprogress.org/2010/05/31/newsweeks-stefan-theil-uncertain-science-climate-denier/ Always best to see both sides, and here we see the Newsweek article exposed as rubbish, including the last paragraph.

Having read those two articles now, I don't think it is quite as black and white as that. The response from the "other side" also contains a good deal of bias, but from the pro-AGW perspective as opposed to the anti-AGW one.

The reference to the Neweweek article as emphasising a "climate denier viewpoint" is somewhat OTT. The Newsweek article acknowledges that AGW exists, but plays up the uncertainties associated with AGW, which is not the same as saying something along the lines "AGW is a myth". This is a case of lumping climate sceptic positions together with extreme denier positions.

The main problem with the article was tarring climate scientists with the same brush as politicians. I see a lot of the problems that it describes, but it is usually a political problem, trying to make out that the science is more cast-iron black and white than it is, and not a problem with climate science as the article infers. I think that aspect of it was addressed quite fairly, though with a rather arrogant tone.

Regarding public opinion on AGW, I think both the article and the response are guilty of taking individual surveys of public opinion and drawing strong conclusions from them- one apiece to suit the opposing agendas ("AGW isn't taken seriously" vs "yes it is").

A couple of points from the response that I think are extremely open to question:

As I’ve noted many times, the possibility we are greatly overestimating the sensitivity is very, very low, whereas the possibility we are greatly underestimating it — and hence greatly underestimating the chances of catastrophic impacts — is quite high.

The overwhelming majority of the recent scientific literature has raised concerns that the extent and time frame of human-caused global warming is graver and faster than what the IPCC — let alone most of the media — reported

Neither of those tally very well with the range of papers that I've seen on the subject- including those printed in the likes of Nature, Journal of Climate etc. All papers are agreed that the recent warming that can be attributed to AGW is not less than the lower bound of the IPCC's uncertainty estimates, while some warn that it may be progressing at a considerably larger rate. But the consensus strikes me as being more that the current warming is in line with what the IPCC expected from AGW, not well in excess of it.

And as for the uncertainties, many papers point to potential uncertainties in both directions. Furthermore, the reliability of conclusions regarding AGW, in climate model driven simulations, are dependent on the reliability of climate models, which although being the best we have, are not strong enough to support such a sweeping statement as that in bold. In fact I think such an assertion is as bad as the frequent implication that uncertainty on AGW implies that it is being overestimated and ignoring the possibility of underestimation.

There are also doubts about the "globally the warmest winter on record" status for 2009/10 and downplaying the cold over Europe (2nd coldest winter in 100 years in Scotland- not exceptional?). This is only true if you accept the NASA/GISS stats as gospel and ignore the NCDC and CRU stats, which have it inside the top five but not a record-breaker. I've seen the argument "GISS includes the Arctic" used in support of that stance, but am yet to see climate scientists coming out in numbers rejecting NCDC/CRU data- they may well have other advantages that GISS does not have. (For sake of balance, it's worth noting that NCDC has January-April 2010 combined as the warmest on record globally, albeit only with a couple of hundreths of a degree in it).

As for the "debunking" of the last paragraph, it is clearly assumed that the reference to "certainty" implies "we should do nothing about AGW unless it is absolutely certain"- a strong case of "reading between the lines" and not necessarily what was intended. The last paragraph even offers AGW as a reason to take action, but downplays the significance of it. I think it is very reasonable to state the other reasons for promoting more sustiainable approaches- even if AGW is a more serious threat than the others- because the public and governments are more likely to take more notice if numerous reasons are "pushed" rather than just one of them.

So while the initial article contains numerous flaws, the attempt to expose it as rubbish also contains numerous flaws.

[Admiral_Bobski]

C-Bob, have a read of:

http://www.skeptical...bal-warming.htm

You'll see the relative amounts of heat injected into the atmosphere and ocean since 1950. The rest of teh article is instructive reading too. Most anthropogenic warming is going into the ocean, only a little is warming the atmosphere. ENSO does not do that. You're still not showing me a long-term trend in ENSO either, only suggesting what might be, and so no I don't agree with you.

http://www.skeptical...ming-going.html

I'll read those links through later on, but you're missing the point.

I'm pointing out that the ENSO fluctuations, in and of themselves, are not the be-all and end-all of the ENSO phenomenon - you are not taking into account the relative insolation at every point during the ENSO cycle.

If you're going to be pig-headed about it and not actually address the issue that I am raising then I'm not going to bother discussing it with you. But then that seems to be an ongoing trend in these debates - answer the question you can answer - even if it wasn't the question that was asked - but evade the question that you can't answer.

Edited June 3, 2010 by Captain_Bobski

[sunny starry skies]

So what, CB, then the changes in relative insolation would be the driver, not ENSO. Since it's well established that the Sun cannot be the dominant driver (incompatible spatial pattern in the atmosphere), clouds show little response (albeit with relatively large uncertainty), what drives relative insolation, or energy input into the oceans and atmsphere? How about increased CO2? This is ridiculous. You'll be telling me that McLean et al were right, next! Seriously, CB, maybe it isn't worth discussing with you if you don't make sense.

TWS, yes, Climate Progress may lean a little farther over to one side, but at least it's supported by evidence. Sure it was cold in Scotland, but despite what had to be about ideal conditions, record temperatures weren't set. That, I find remarkable. And a fairly nondescript day (synoptically) two weeks ago set record May highs in parts of Scotland. But I am of course aware enough that Scotland is not the world, and cold air here came from somewhere, and overall most other regions were warmer than average, as shown in all datasets.

You emboldened a statement that actually I'd agree with. And many of those sensitivity estimates are not made with models - notably palaeoclimatic ones. I've yet to see anything much credible that places sensitivity below 1.5C/doubling (Knutti and Hegerl is a good place to start there), 3C is quite likely, and higher sensitivity is estimated by some when looking at Pliocene climate, and cannot exactly be ruled out, unfortunately.

http://climateprogress.org/2010/05/17/hurricane-season-record-atlantic-temperatures-hottest-april/

http://climateprogress.org/2010/06/01/record-heat-wave-may/

And the hottest 12-month period in the GISS record. Hmmm, certainly no sign of cooling...

If I've avoided questions, it's because of the veritable gish gallop of non-sensical claims that I'm trying to deal with. I fear it's going to be time to fade into the background rather than try and explain the basics to people unwilling to accept some or all of : that CO2 is a greenhouse gas, we're significantly increasing the concentration in forcable amounts, we expect that to cause warming, we're observing the warming, we're observing the greenhouse effect actually happening, the spatial pattern of that warming is distinct to GHGs, and the responses of the cryosphere, biosphere, oceans and atmosphere are essentially exactly what we expect.

One last link for now:

http://www2.sunysuffolk.edu/mandias/global_warming/index.html

Some nice links here from Prof Mandia with explanations as to why it's humans, the role of natural variations, the size and impact of the fossil-fuel-funded denial machine (quite an eye-opener) among a host of other topics.

ta ta the noo, happy debating!

sss

[Admiral_Bobski]

So what, CB, then the changes in relative insolation would be the driver, not ENSO. Since it's well established that the Sun cannot be the dominant driver (incompatible spatial pattern in the atmosphere), clouds show little response (albeit with relatively large uncertainty), what drives relative insolation, or energy input into the oceans and atmsphere? How about increased CO2? This is ridiculous. You'll be telling me that McLean et al were right, next! Seriously, CB, maybe it isn't worth discussing with you if you don't make sense.

Well, yes - insolation is the driver, when all is said and done, but it's not an instantaneous driver, which is what I've been trying to get at for well over a year.

I'm also still not convinced, obviously, that the "spatial pattern in the atmosphere" is incompatible with insolation being the main driver, and it's an issue I am still trying to resolve - but one slight downpoint does not, to my mind, render all the other points redundant.

I have been trying to seriously approach this issue from an alternative viewpoint, my arguments are logical and - where necessary - I have conceded errors and even altered my viewpoint (which has, in turn, led to an adaptation of my arguments - but this is not the same as leaping from argument to argument, you understand). What have I got in return? Scoffing, patronising, frankly insulting drivel from you. You say that I don't make sense? Well, plenty of other people on here seem to think I'm making some kind of sense, so the fact that you will not allow yourself to consider an alternative to the All-Hallowed AGW shows you to be a closed-minded jerk.

Since you still will not tackle the point that I have actually raised then I see no reason to continue this discussion. And you have still not responded to my points about the Milankovitch cycles beyond saying "some people disagree with you". I really am sick of the whole thing - the only reason I continue to stick my oar in these discussions is that I hate to think that the absence of sensible skeptic voices makes some people think that the AGW debate is settled.

I think I should give up, not because "you've won" but rather because you won't listen, you won't reason, you won't discuss, you won't consider and you won't treat others with any kind of respect.

If I've avoided questions, it's because of the veritable gish gallop of non-sensical claims that I'm trying to deal with.

You're trying to deal with? What, single-handedly? Well, what a martyr you are to The Cause.

[VillagePlank]

<snipt>

That's me out of it again. I'm not going to go 'back to basics' and my normal mathematical skill is not in doubt - it is awful, as always.

Carry on, guys.

Edited June 3, 2010 by VillagePlank

[jethro]

Goodness me, how quickly this all descends. Yet again.

Is there really any point in having a Climate area on this forum if the simplest of debates cannot be had without the petty bickering?