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Posted
  • Location: Sunny Southsea
  • Location: Sunny Southsea

Apparently, the time it takes for the global system (especially the oceans) to respond to (CO2?) forcing in the atmosphere is in the order of 50-100 years.

So, the warming 1900-1940 and the warming 1970-2000 are in part responses about fifty or more years behind the increases in CO2, which would imply that the speed of warming for 2000-2030 and onwards is likely to be even faste, responding as it will to the twentieth century increases in FF burning. I think that's right. Certainly, in 1988 Hansen suggested that the 'real' warming would not start kicking in till 2000, which syggests this analysis is broadly correct.

:)P

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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
Apparently, the time it takes for the global system (especially the oceans) to respond to (CO2?) forcing in the atmosphere is in the order of 50-100 years...So, the warming 1900-1940 and the warming 1970-2000 are in part responses about fifty or more years behind the increases in CO2...

So you're saying that we should be looking at the CO2 data from 1810-1840 up to 1860-1890 to compare with temperatures over 1910-1940, and similarly looking at 1870-1900 up to 1920-1950 to compare with temperatures over 1970-2000.

We are often reminded that temperatures are increasing, and we've pushed CO2 levels over 100ppm above "normal" levels, and that there is some kind of causality between them. But, assuming only a fifty year lag, the 1910-1940 warming would have been caused (at least in part) by an increase in CO2 concentrations of only about 5ppm (presumably a 100 year lag would make the CO2 increase smaller still). Taking the 1970-2000 warming with the same 50 year lag you would be talking about an increase of around 10ppm.

Could that relatively small increase actually have the observed effect? The more I find out about this, the more unlikely it sounds. To me, anyway. I'm sure there's more to it than this, and that it is far more complicated, but it still just seems wrong to me... Yet more digging required!

:doh:

CB

EDIT - Also, if that original 5ppm increase really did have an effect then one would expect the later increase of 10ppm to have an even greater effect, which still begs the question of why the two warming trends (1910-1940 and 1970-2000) are so very nearly identical.

Edited by Captain_Bobski
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Posted
  • Location: Sunny Southsea
  • Location: Sunny Southsea

You'll also want to take Ruddiman's hypothesis into account, according to which there is a measurable human climate signal going back 8,000 years, related to the clearance of forests and the development of agriculture, changing albedo, soil moisture & evaporation (& cloud?) & CO2 sinks. It's also important to consider total population levels, as well as the industrial revolution in Europe and the 'taming' of the USA; a lot of small variables which add up to a small but measurable signal. It could also be argued that the negative forcings from 'dirty' industry could more or less have balanced (or at least masked) the positive forcings from CO2 or insolation changes; it makes for a complex set of calculations.

:)P

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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
You'll also want to take Ruddiman's hypothesis into account...it makes for a complex set of calculations.

It certainly does - so complex, in fact, that I'm not even going to try that one! However, the apparent similarity in gradients still bothers me...

:doh:

CB

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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

We have also got to remember that both pollution and CO2 are rising throughout the period. We are only starting to see benefits from the 'clean air act' period (65-85) so there are an awful lot of variables (most on an increasing slope) and a change in the types of 'common' Pollutants (apart from the CO2). As P3 reminds us the CO2 influence is not only skewed by dimming but also has a 'lag' in it's effects.

Again I have to say that the oil lobby tinkering through the 70's,80's and 90's has led us to a 'climate of distrust' where everyone jumps on any discrepancy and calls it a fatal flaw to the hypothesis of AGW. There is not satisfaction in knowing that the doubters will end up with egg on their faces as we start to witness both the 1950's CO2 effects and the impact that 'cleaning up our act' has had on sunlight strength.

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Posted
  • Location: Sunny Southsea
  • Location: Sunny Southsea

If you take the period 1900-2000 as a continuous one, with the 'aerosol hiccup' in the middle 30 years, and then look at the CO2 levels from, say, 1950 back to 1850, you could say that the CO2 conc. only rises in a relatively flat curve, whilst the temp rises in a comparable line. This would also imply, though, that it only took a forcing of about 40ppm of CO2 to produce a warming of ~ 1C.

But the palaeo record suggest two more numbers; a rise of ~10C associated with a CO2 rise of only 100ppm, of which approximately #1-2C is normally considered to be due to CO2. The Equilibrium climate sensitivity to a doubling of CO2 is normally set around 2.5-3.5C.

So, is it: 40ppm = 1C; 100ppm = 1-2C; or 275ppm = 2.5-3.5C ?

My summary of these numbers ends up with a ballpark relationship of CO2 to Temperature of about 1C per 100ppm over and above the pre-industrial levels. This is not taking into account other forcings or feedbacks (let's assume the feedback effects would be delayed slightly, anyway.

Is there a period in the CO2 record where the figure rises ~100ppm? Only over the past 100-150 years (the first fifty of which are part of a slow rise, anyway). Does the temperature rise about 1C during this time? Yes. Even if there is a fifty year lag, it is still possible to get the numbers to stack, but the problem is that the graphs tend to show the correlation between current temp and current CO2, when, if this was right, they ought to show Current temps. plotted against CO2 fifty years ago: How does the correlation look then?

:)P

Edited by parmenides3
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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

Well done P3!! I far fewer words than I could manage you have hit the nail on the head.

Whilst folk are looking at temp rise and CO2 levels as 'comparable' they are making a mistake of underestimation of the CO2 and it's effects.

There are so many variables just within the industrial outputs over time never mind the planets attempts to mitigate them via the ultra complex climatic responses.

Maybe we do just need to 'pull back' and look at the oversimplified picture in an effort to just to get to grips with the slippery beasty that we're playing with.

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Posted
  • Location: Sunny Southsea
  • Location: Sunny Southsea

Ah Ha! Here, courtesy of NOAA, are the formulae for radiative forcing calculations and a table of the sums since 1979. (scroll down the page).

If I spent a while, I'd probably be able to work out what the formulae say, and do the numbers. http://www.esrl.noaa.gov/gmd/aggi/

Isn't the internet a wonderful thing?

Hope this is interesting/useful to you students of the subject.

:)P

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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
Again I have to say that the oil lobby tinkering through the 70's,80's and 90's has led us to a 'climate of distrust' where everyone jumps on any discrepancy and calls it a fatal flaw to the hypothesis of AGW. There is not satisfaction in knowing that the doubters will end up with egg on their faces as we start to witness both the 1950's CO2 effects and the impact that 'cleaning up our act' has had on sunlight strength.

I think that's a little harsh, GW, or if not harsh then somewhat overstated. I don't think that the oil lobby created a climate of distrust: I think the climate of distrust has always been there and the oil lobby have merely reinforced it. I, for one, have been very cautious in my approach to these various misgivings of mine (discrepancies, if you like), but I have not called them "fatal flaws". In fact I have been very specific in claiming that these discrepancies may cause problems with the theory without actually being fatal. Yes, there are skeptics who will claim these are fatal flaws, but I figure they are just the yin to the pro-AGW "Catastrophist"'s yang.

I also wonder how it is that you "know" that "doubters will end up with egg on their faces" - you may think that doubters will end up with egg on their faces. You may suspect it. You may even be positive that this is the case. But I don't think that anyone can honestly say that they know that to be the case.

I know for a fact that one of three things will happen in the next 50 years: either temps will continue to rise, or they will level off, or they will decline. Although there may be compelling evidence that temperatures will continue to increase, it is by no means certain. Some evidence suggests that temperatures may drop off, although this is far less well-supported.

Personally, I have suspicions that those who support AGW theory could end up with egg on their faces within the next twenty to fifty years - I am by no means certain of this, but I suspect that it is a distinct possibility. If that were to happen I won't be rubbing anyone's nose in it - we can all just move on...

:nonono:

CB

EDIT - P3, thanks for the link and info. A quick question for you: how are the constants for each GHG derived? (The answer's probably "out there", on the web, somewhere...but I'm being lazy! :good: )

Edited by Captain_Bobski
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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......
I also wonder how it is that you "know" that "doubters will end up with egg on their faces" - you may think that doubters will end up with egg on their faces. You may suspect it. You may even be positive that this is the case. But I don't think that anyone can honestly say that they know that to be the case.

;)

CB

Because I read up on the latest Scientific research and, from NOAA/NASA, the latest interpretation of the Vostok cores around the start of the Eemian gives a perfect match for the last 70yrs of warming. This would mean a warming of 8c over the next 15-30yrs in line with other interglacial retreat episodes.

The special IPCC paper, released today, also give a dire warning (now the deep sea ARGO data is included) on sea level change with the same 30yr period expected to show a 7m rise.

The B.A.S. (on their side of Antarctica) have show slumping in the area feeding the Pine Glacier suggesting a 'domino effect' is occurring from upland plateau to ice sheet.

All that aside if you look at the new 'cycle 24' data from SOHO it would appear that not only are we to expect the 'busiest' solar cycle recorded but also an increase in solar output approaching 30%.

So what do you say now???

Well I say.....................

APRIL FOOL!!!!!

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Posted
  • Location: Cheddar Valley, 20mtrs asl
  • Weather Preferences: Snow and lots of it or warm and sunny, no mediocre dross
  • Location: Cheddar Valley, 20mtrs asl

http://www.iarc.uaf.edu/highlights/2007/ak...ng_from_LIA.pdf

Found this today on Accuweather, thought some would find it interesting.

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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......
http://www.iarc.uaf.edu/highlights/2007/ak...ng_from_LIA.pdf

Found this today on Accuweather, thought some would find it interesting.

I'd already tracked it down ( in true P3 'stylee') and it just re-affirms in me that we have more than our 'dabblings' to worry about. Folk will be worried (but reassured) by the IPCC report but we must remember that they are sticking to as firmer ground as they can find within the report. Anything that isn't 10yrs old and proven beyond even the biggest 'doubters' quizzing seems to be omitted. My personal stance is that the next 5 yrs will show ,in action not measurement, the scale of our problems and they will be far beyond 'controlling'. Better we cut our losses and adapt where we can. It will mean global catastrophies but we're becoming hardened to brown babies starving aren't we?.

Edited by Gray-Wolf
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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
http://www.iarc.uaf.edu/highlights/2007/ak...ng_from_LIA.pdf

Found this today on Accuweather, thought some would find it interesting.

Good find there, Jethro! (and GW :D ) There's also a good article by Dr Akasofu entitled "Why has global warming become such a passionate subject? Let's not lose our cool" which can be found in pdf form here:

http://www.iarc.uaf.edu/highlights/2007/ak...bal_warming.pdf

I could really grow to love this guy - we have so much in common!

:D

CB

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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......
Good find there, Jethro! (and GW :D ) There's also a good article by Dr Akasofu entitled "Why has global warming become such a passionate subject? Let's not lose our cool" which can be found in pdf form here:

http://www.iarc.uaf.edu/highlights/2007/ak...bal_warming.pdf

I could really grow to love this guy - we have so much in common!

:D

CB

Hi C-Bob! Sorry for my outburst the other night. I know I shouldn't post my feelings as positives but I'm not as self controlled as I might be. Hope you accept my appologies!

Ian.

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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
Hi C-Bob! Sorry for my outburst the other night. I know I shouldn't post my feelings as positives but I'm not as self controlled as I might be. Hope you accept my appologies!

Ian.

No need to apologise! I hope no offense was taken at my rather brusque reply... :D

CB

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Posted
  • Location: Sunny Southsea
  • Location: Sunny Southsea

Roger Pielke Sr. features a guest blog by the good doctor on Climate Science http://climatesci.colorado.edu/

I read the two pieces on his links and left the doc. a couple of questions, but there wasn't much response.

I had thought to go through the 'ice age' paper in some detail and put some stuff on my own blog, but with the IPCC part 2 due out in a couple of days, the blogosphere is likely to be full of dire warnings and rantings and ravings, so I might not get the time. Is it worth it?

I'll do a hard analysis if you want, but there'll be plenty to discuss in the next few days...

:)P

PS: C-Bob; sorry, haven't pursued your question on the origin of the GHG formulae yet...

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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
Roger Pielke Sr. features a guest blog by the good doctor on Climate Science http://climatesci.colorado.edu/

I read the two pieces on his links and left the doc. a couple of questions, but there wasn't much response.

I had thought to go through the 'ice age' paper in some detail and put some stuff on my own blog, but with the IPCC part 2 due out in a couple of days, the blogosphere is likely to be full of dire warnings and rantings and ravings, so I might not get the time. Is it worth it?

I'll do a hard analysis if you want, but there'll be plenty to discuss in the next few days...

:)P

PS: C-Bob; sorry, haven't pursued your question on the origin of the GHG formulae yet...

Thanks for that P3. I Googled "Akasofu" and saw that he'd guested on Climate Science, but I haven't read the post there yet. I remember Dr Akasofu being on the "Swindle" programme, and I had intended to look him up at the time but I didn't get round to it - I shall make a point of reading more of what he has to say on the subject of climate change. From the little I have read it seems apparent that he and I share many of the same views, which is rather interesting (in that I'm glad I am not alone in barking up this particular tree! Whether it's the right tree or the wrong tree is another matter...).

I look forward to the next part of the IPCC report - I'm hoping there'll be something rather meatier to get my teeth into than the SPM. I can't believe part 2 is due out already - hasn't time flown by this year?!

As for the derivation of the GHG constants, don't worry too much - as I said at the time, the answer's probably out there in cyberspace somewhere. I was just being lazy, and I thought that if anyone knew off the top of their head it would be you. I think it is important to know where they get these figures from, but it's not pressingly urgent right now...! I'm sure the answer will present itself when the time is right. :shok: (But thanks anyway - it's nice to know you were still thinking about it!)

CB

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Posted
  • Location: Sunny Southsea
  • Location: Sunny Southsea

Hah! The expressions on the NOAA page are those recommended by the IPCC TAR. So we go round in a circle. Not much help...

As tyo where the TAR got them, I'm working on it.

:)P

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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
Hah! The expressions on the NOAA page are those recommended by the IPCC TAR. So we go round in a circle. Not much help...

As tyo where the TAR got them, I'm working on it.

:)P

If the TAR got them from the NOAA page then we're all in big trouble! :shok:

CB

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Posted
  • Location: Sunny Southsea
  • Location: Sunny Southsea

Found this page on how the whole thing is supposed to work, thanks to Rabett Run: http://capitalistimperialistpig.blogspot.c...ers-it-all.html

I can't vouch for its accuracy, but it sounds about okay. Think it may help. See under 'Cap explains it all'

;)P

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