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  4. What proportion of global warming is attributable to humans?
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What proportion of global warming is attributable to humans?

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Offline peppercorn

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What proportion of global warming is attributable to humans?
« Reply #60 on: 25/11/2009 14:14:08 »
Quote from: litespeed on 24/11/2009 18:12:26
emails hacked from the Director of University of East Anglia
Good grief! The 'denialist' camp must be be in dire-straits if we have sunk to a level where commenting on one alleged email that can't be substantiated is banded about  - on this site of all places.  In any case, one bad egg does not a conspiracy make!  This sort of thing is a distraction at best and should not be posted in the first place.

Quote from: litespeed on 24/11/2009 19:11:16
What Damage? All industrial nations have cleaner environments now then at any time in the last many hundreds of years.
I think you're confusing cleaner environments with better air quality.

Quote from: litespeed on 24/11/2009 19:11:16
Reducing CO2 from industrial societies is little more then self-flagelation
Do you want to explain that rhetoric, please?



Quote from: frethack on 24/11/2009 22:38:57
It is not yet known whether it is a true cycle, or an internal response from the climate system, but the period actually has a somewhat wide range in error at 1500 +/- 500 years.
Thanks for the offer of sending the paper.  I'm sure it would be interesting, although being out of my field I will take it's rigour on trust at present.
That said, I have some a couple of queries that you might be able to illuminate on.
First, what do you mean by "internal response"?
Second, a fifty percent error margin - how can anything be analysed or predicted from that?  And even that assumes that the extrapolation for the core samples is valid.
Thirdly, let's just say, for arguments sake that this analysis is right on the money, what does it give us as a prediction of future climate trends? Does it indicate in any good-science way a climate maxima is happening?
« Last Edit: 25/11/2009 14:30:54 by peppercorn »
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Offline litespeed

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What proportion of global warming is attributable to humans?
« Reply #61 on: 25/11/2009 23:44:02 »
fret - You wrote: "First, what do you mean by "internal response"? I don't have a clue, but also have the epistomological advantage of not having written it.

You also wrote: "Second, a fifty percent error margin - how can anything be analysed or predicted from that?"  1,500 years plus/minus 500 is not fifty percent, and it is not an error margin, it is, I THINK, an observed variation.  None-the-less, those who argue this point tell us they observe this particular cycle in historical times, and we are now due for a warming.  Which, IMHO, is WAY better then the alternative.

As for the embarrassing email?  There is not just one. There is an entire sequence. I don't know how serious it is.  But hell, the guy flat out says he is manipulating the data. 

Flagelation?  The industrial world can begger itself back to huddling in caves without fire at all while India and China, about half the world population(?), build thousands of coal plants without even modern SO2 scrubbers. Its entirely pointless. Farting into a hurricane.






« Last Edit: 25/11/2009 23:46:33 by litespeed »
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Offline Karsten

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What proportion of global warming is attributable to humans?
« Reply #62 on: 26/11/2009 00:17:20 »
Quote from: litespeed on 25/11/2009 23:44:02
Flagelation?  The industrial world can begger itself back to huddling in caves without fire at all while India and China, about half the world population(?), build thousands of coal plants without even modern SO2 scrubbers. Its entirely pointless. Farting into a hurricane.

Depends on what you want to achieve. Do you want to stop or slow down the hurricane or do you want to get better at farting? I for one think that it would be wise to practice farting. We (in the USA) are lousy at it and it would be of great advantage to be so skilled that it will allow us to live entirely without hurricanes. Or at least smaller storms. We could even become one of the world's leaders in farting technology. Although it will be hard to catch up with the Europeans. Great farting going on there. I believe even the Chinese are practicing farting while they are building up the hurricane simultaneously. Now that we have created a hurricane ourselves, we just sit on our asses, expect to reap the benefits, and do nothing. Not knowing how to fart at a really big scale leads to "Developing County" status.
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Offline frethack

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What proportion of global warming is attributable to humans?
« Reply #63 on: 30/11/2009 17:12:17 »
Quote from: peppercorn on 25/11/2009 14:14:08
First, what do you mean by "internal response"?

Sorry, the term is a little vague.  What I meant by "internal response" is the climate system reacting to a number of forcing agents that just happen to culminate about every 1500 years rather than a direct response to a single (or a few) forcing agents.  Say that Greenlands continental glaciers begin advancing because their accumulation rates overcome ablation (melting...sort of).  Because of this advancement, large ice rafting events occur in the N Atlantic as the glaciers calve off icebergs, which causes a freshening of the normally dense, salty water in the N Atlantic, and pushes the overturning circulation slightly southward (the meridional overturning circulation "recycles" surface water into deep water currents, somewhat like a conveyor belt).  This in turn would also cool the northern latitudes because heat is no longer carried as far north by the surface currents, and allow sea ice to extend further south...perpetuating the "cycle".

This is a very brief (and likely poorly written) synopsis of one hypothesis for Heinrich events.  DO events and Heinrich events are related in that DO events are warming periods lasting on centennial time scales with intermittent cool periods.  Some of these cooling periods have very large ice rafting events called Heinrich events, which appear to have a loose periodicity.

Quote from: peppercorn on 25/11/2009 14:14:08
Second, a fifty percent error margin - how can anything be analysed or predicted from that?  And even that assumes that the extrapolation for the core samples is valid.
Thirdly, let's just say, for arguments sake that this analysis is right on the money, what does it give us as a prediction of future climate trends? Does it indicate in any good-science way a climate maxima is happening?


You would be very surprised at the error margins involved in almost all areas of climate research.  This particular one is not 50%, but about 33%.  As for the extrapolation from the core samples...DO and Heinrich events are repeated over many different types of proxy records from all over the world.  The timing and degree of climate system response varies somewhat from region to region, which is to be expected, but it is pretty certain that they have occurred. 

*If* solar activity is the main forcing agent for these events, as well as the cooling and warming events during the Holocene, it would be expected that the very high solar activity of the past 150 years or so would produce a climate optimum.  Even if this is proven the case (which could take many more years of research) that still does not mean that *all* of the warming being experienced is from natural sources.

Sorry it took me so long to reply...I love the holidays :)

 

« Last Edit: 30/11/2009 17:43:05 by frethack »
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Offline litespeed

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What proportion of global warming is attributable to humans?
« Reply #64 on: 01/12/2009 17:37:58 »
Hi Kartsten,

I understand Indians [from India] do a lot of loud farting, and may actually be a sort of status symbol for being well fed.  Cows and other ungulant animals are WAY good at this. Thus the term 'Holy Cow'. I believe some people support various types of vegetarianism in order to cut down on cow methane.

On the otherhand, trash dumps have become so technically efficient that methane is sometimes harvested from rotting trash. Further, human farts are also ignitable. As a college freshman we tried to convince one of our room mates of this.  He was skeptical but agreed to lay back on the lower bunk, put his feet on the underside of the upper bunk, while we held a butane lighter in the proper location.

He really let one go resulting in a perfect six or seven inch blue flame. This scared the living hell out of him and he ran from the room like, well, his butt was on fire, and quenched it all in the shower nearby.  One of the better stories of my long accademic life.....
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Offline litespeed

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What proportion of global warming is attributable to humans?
« Reply #65 on: 01/12/2009 18:12:00 »
fret - Your observations on margin of error are well taken. Its one reason I am a skeptic in general. During the 1970's oil embargo we were assured natural gas supplies would be exhausted in ten years. For Sure! 

I noticed unused tennis courts and office buildings brightly lit late at night and actually considered starting a small buisiness to provide specialized lighting management for such things.  We would contract with businesses and government to ensure lighting was turned off late in the evening after every one was gone. The Lighting Police! Now natural gas supplies are estimated at two hundred years. Decorative outdoor lighting in metropolitan areas is routine. Jeeze......

Also during the 1970's we were assured the signs of a New Ice Age were 'everywhere'. Over time I began to understand the social dynamics of hysteria. These hysterias range from poisoned Jack in the Box Taccos, to 'give up colesterol eggs' to the various statins to reduce cholesterol.

For decades I have challenged my physicians to provide studies showing statins routinely increased life expectancy in healthy people. HA! Talk about tortured science. They never even argued with me very much. Sort of shuffled their feet and mumbled about this or that advantage. In fact, EYE was the one who informed them of studies showing Simvistatin apparently has a huge impact on reducing dimentia in Veterans Administration studies. It seems to be the only LARGE advantage, and is limited to this particular statin.  But mums the word..... 

So. I get suspicious when people support GW by showing photographs of forlorn Polar Bears, or seem entirely ignorant of actual cyclical ups and downs within historic times. And of course they do themselves no service in trumpeting this hurricane, or that hot summer, or a cluster of toronadoes as support for their views. Its just rediculous. More specifically, the Little Ice Age endend in the mid to late 1800's.  And it got warmer. What in the living hell did they expect?

Now its getting cooler. For now. I just hope it does not get COLD, like the Little Ice Age.....

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Offline litespeed

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What proportion of global warming is attributable to humans?
« Reply #66 on: 01/12/2009 18:40:51 »
fret - In addition to the very large margins of error in the variables we know, it seems clear we do not have anything near a complete list of variables.  For instance, I believe most vocanic activity takes place in the oceans. I have never even seen this listed as a variable, much less a quantification of the effects, or if these effects change over time.

It reminds me of The Drake Equation used to estimate the number of advanced civilizations in the Galaxy.  I think Drake plugged in some Wild Ass Quesses, and came up with less then twenty. Over the years, on a routine basis, some SETI reasearcher or another expresses absolute confidence we will discover such a civilization within x number of years. This usually happens after plans are made for ever more sophisticated detection methods.

Then actual data started coming in. Two things happened. First, the number of variables in the Drake equation started increasing. For instance, he never considered the importance of our specific, and very weird, moon. The equation for that variable adds orders of magnitude AGAINST the advanced life.  Seems you need just the exact size of an impact planet impacting the earth at just the exact angle and speed.  Without this you do not get a stable climate on the planet. Think a four bumper bank shot on a pool table to sink the eight ball.

Further, the original equation did not include consideration of Gas Giants.  It turns out you really really need at least one Gas Giant in the outer solar system to police up potential catastrophies such as Shumaker Levy Comet. But it gets worse.  We have now detected perhaps three hundred extra solar planets, and quess what. All but one of these systems have Gas Giants in their Inner Solar systems. Scratch 299 Goldie Locks orbits.

And the one rocky planet detected is too close to its sun.  I know something about statistical sampling, and all this is really really bad for the Drake Equation.
« Last Edit: 01/12/2009 18:43:42 by litespeed »
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Offline peppercorn

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What proportion of global warming is attributable to humans?
« Reply #67 on: 02/12/2009 09:26:13 »
Quote from: frethack on 30/11/2009 17:12:17
What I meant by "internal response" is the climate system reacting to a number of forcing agents that just happen to culminate about every 1500 years rather than a direct response to a single (or a few) forcing agents.
Thanks for the explanation, frethack.
So, if my understanding is correct, this very general climate trend could either be related to some sort of long-term variation in energy input (most likely solar) OR a purely climatic feedback loop of one kind or another (I.E. influenced by many factors perhaps including northern sea salinity cycles).

I'm sure you would agree that the single outstanding conclusion that we can draw from this sea ('scuse the pun!) of observation and analysis is that our world's climate approaches one of the most complex and hard-to-predict systems Man has to deal with.

There is, at the same time, some very fundamental aspects that affect our atmosphere.  They include very well understood chemical interactions, including the spectral absorption of atmospheric gases.  It just seems foolish in the extreme to add Our own random impacts to a system we are still in the infancy of understanding.

Quote from: frethack on 30/11/2009 17:12:17
*If* solar activity is the main forcing agent for these events, as well as the cooling and warming events during the Holocene, it would be expected that the very high solar activity of the past 150 years or so would produce a climate optimum.  Even if this is proven the case (which could take many more years of research) that still does not mean that *all* of the warming being experienced is from natural sources.
Even the most direct sampling from ice cores, etc seem to give a far from decisive image about what the Earth's climate looked like in any one period.  It would seem folly to claim as anything more than conjecture that this ambiguous evidence points to more than a bit-part for solar variation in the overall climate history.
Under the current circumstances of our known impact, I hope it will take a great deal more proof than this for any scientist working in the field.
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Offline frethack

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What proportion of global warming is attributable to humans?
« Reply #68 on: 02/12/2009 14:02:09 »
Quote from: peppercorn on 02/12/2009 09:26:13
So, if my understanding is correct, this very general climate trend could either be related to some sort of long-term variation in energy input (most likely solar) OR a purely climatic feedback loop of one kind or another (I.E. influenced by many factors perhaps including northern sea salinity cycles).

It would very much surprise me if it were an either/or situation.  The solar effect is very obviously there.  The radio nucleotides produced by variations in solar activity are very well correlated with major IRD events, but there are a few excursions that appear to be solely within the system.  There are more than a few papers on this subject, and if you would like, after finals are over I can compile a list.

Quote from: peppercorn on 02/12/2009 09:26:13
I'm sure you would agree that the single outstanding conclusion that we can draw from this sea ('scuse the pun!) of observation and analysis is that our world's climate approaches one of the most complex and hard-to-predict systems Man has to deal with.

Yes, absolutely.  Without question.

Quote from: peppercorn on 02/12/2009 09:26:13
There is, at the same time, some very fundamental aspects that affect our atmosphere.  They include very well understood chemical interactions, including the spectral absorption of atmospheric gases.  It just seems foolish in the extreme to add Our own random impacts to a system we are still in the infancy of understanding.

You are mostly very correct.  However, I am still waiting to see a paper that can quantitatively measure the radiative properties of the various greenhouse gasses.  We know that it happens, but its the "how much" that I want to know.  There are other gray areas as well, such as cloud nucleation, which we understand next to nothing about.  The importance of understanding this process cannot be overstated, as clouds are a major factor in the earths albedo.

Quote from: peppercorn on 02/12/2009 09:26:13
Even the most direct sampling from ice cores, etc seem to give a far from decisive image about what the Earth's climate looked like in any one period.

One core cannot do much on its own, but a multiproxy approach that establishes a very large body of evidence can begin to reveal the big picture.  We know a lot more than we did 20 years ago and can make some educated assertions, but much more work is necessary. 

Quote from: peppercorn on 02/12/2009 09:26:13
It would seem folly to claim as anything more than conjecture that this ambiguous evidence points to more than a bit-part for solar variation in the overall climate history.

If this were the only major evidence for solar influence, I would agree with you.  As I said, there is MUCH more to post, which I can return to after finals are over.  In perspective, the sun effectively provides the earths climate system with 100% of its energy.  There are other sources of energy input (cosmic radiation, volcanism (general tectonics), magnetism, etc.), but they comprise only a very small fraction of a percent of the total energy compared to that received from the sun.  In my opinion, the folly is in thinking that variations in the single source of energy to the climate system would have little effect here on earth.

Quote from: peppercorn on 02/12/2009 09:26:13
Under the current circumstances of our known impact, I hope it will take a great deal more proof than this for any scientist working in the field.

As I stated above, this is not a single, lone paper that researchers are basing their findings on.  It was merely a paper by a scientist (who is very well respected on both sides of the debate) that can serve as a starting point to post more evidence.  It is worth stating that there are a good many reputable scientists researching solar influences on climate.  After finals are over I can begin posting the larger body of evidence (which by no means will be exhaustive...there is more out there than I can feasibly post).
« Last Edit: 02/12/2009 14:08:40 by frethack »
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Offline peppercorn

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What proportion of global warming is attributable to humans?
« Reply #69 on: 02/12/2009 14:56:06 »
Quote from: frethack on 02/12/2009 14:02:09
After finals are over I can begin posting the larger body of evidence.
Well, until then, good luck with those finals!
I will take on the generally valid points you've made -  It is good to ensure that no unfounded assumptions have slipped through the net for either argument.

When you are talking about radiative properties of GH gases, I take it you mean their emission spectrum. I would be surprised if those data are not easily found... I will start by Googling it...
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Offline frethack

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What proportion of global warming is attributable to humans?
« Reply #70 on: 02/12/2009 19:01:34 »
Quote from: peppercorn on 02/12/2009 14:56:06
When you are talking about radiative properties of GH gases, I take it you mean their emission spectrum. I would be surprised if those data are not easily found... I will start by Googling it...

Not necessarily their emission spectrum.  What I am looking for is a reproducible experiment that can show that X ppm of CO2 produces Y W/m2 of radiative forcing with Z W/m2 of incoming solar radiation.
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Offline litespeed

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What proportion of global warming is attributable to humans?
« Reply #71 on: 03/12/2009 00:11:09 »
IN GENERAL

Climatologist and the climate models are entirely incapable of modeling the last decade of plantetary cooling. The guys in Bolder Colorado seem entirely perplexed by all the snow shoveling that has come their way. The actual words they use are something like 'inexplicable'. Perhaps they used the word 'travesty' or some such to describe climate modeling failures.

It does not matter much. The CO2 guys are looking more and more like Pope Urban whats his number and Galaleo. My quess is these maniacs are PRAYING for more signs of warming. Unhappily I hope for the same.  The alternative is cooling, famine, pestulance, and all that comes with cold climates.

Who woulda thought....


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Offline frethack

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What proportion of global warming is attributable to humans?
« Reply #72 on: 03/12/2009 03:45:55 »
Quote from: litespeed on 03/12/2009 00:11:09
IN GENERAL

Climatologist and the climate models are entirely incapable of modeling the last decade of plantetary cooling.

You can shorten that even further. How about:

Climatologists and the climate models are entirely incapable of modeling the climate.

If you dont understand or cant even account for all of the input parameters there is little hope of getting anything meaningful from the other end.  That being said, models will hopefully be far more useful once processor capacity and our knowledge of climate progresses.
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Offline Karsten

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What proportion of global warming is attributable to humans?
« Reply #73 on: 04/12/2009 01:20:28 »
Quote from: litespeed on 01/12/2009 17:37:58
Hi Kartsten,

I understand Indians [from India] do a lot of loud farting, and may actually be a sort of status symbol for being well fed.  Cows and other ungulant animals are WAY good at this. Thus the term 'Holy Cow'. I believe some people support various types of vegetarianism in order to cut down on cow methane.

On the otherhand, trash dumps have become so technically efficient that methane is sometimes harvested from rotting trash. Further, human farts are also ignitable. As a college freshman we tried to convince one of our room mates of this.  He was skeptical but agreed to lay back on the lower bunk, put his feet on the underside of the upper bunk, while we held a butane lighter in the proper location.

He really let one go resulting in a perfect six or seven inch blue flame. This scared the living hell out of him and he ran from the room like, well, his butt was on fire, and quenched it all in the shower nearby.  One of the better stories of my long accademic life.....

Litespeed- my comments about farting where supposed to be understood as a metaphor. If we don't do the little things now ("farting into a hurricane", as you put it), we will fall behind developing technology that will help beginning today but later for sure. Especially since China is trying real hard to become the global leader in clean-energy technology while we in the USA still bicker whether it is really necessary and look for novel ways to get entertained.
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Offline Madidus_Scientia

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What proportion of global warming is attributable to humans?
« Reply #74 on: 07/12/2009 03:46:42 »
litespeed, the email you quoted about "hiding the decline" was referring to the temperature data based on tree rings, after 1960 there began to be discrepancies between tree ring data and thermometer data. (The tree ring data declined, whereas other data did not) "Mikes trick" refers to Dr Michael Mann, one of the worlds leading paleoclimate experts, famous for his reconstruction of global temps based on different sources such as corals, ice cores, historical data and of course tree rings, and overlaying all the data onto the same graph.

So the decline he was hiding was from temp data based on tree rings from 1960 onwards. We have instrumental data from this period anyway so unless you believe that tree ring temperature data is more accurate than every other source we have from 1960 onwards, there really is no argument against global warming from this cherrypicked sentence from a stolen email. It is only tree ring temp data that shows a decline, all other indicators follow each other to correlate with instrumental records.

Don't you see how weak it is though that this non-evidence has been bandied about by deniers who don't even understand what it means, as if it's the holy grail of evidence against global warming?

Quote from: litespeed on 03/12/2009 00:11:09
IN GENERAL

Climatologist and the climate models are entirely incapable of modeling the last decade of plantetary cooling. The guys in Bolder Colorado seem entirely perplexed by all the snow shoveling that has come their way. The actual words they use are something like 'inexplicable'. Perhaps they used the word 'travesty' or some such to describe climate modeling failures.

It does not matter much. The CO2 guys are looking more and more like Pope Urban whats his number and Galaleo. My quess is these maniacs are PRAYING for more signs of warming. Unhappily I hope for the same.  The alternative is cooling, famine, pestulance, and all that comes with cold climates.

Who woulda thought....

Regardless of the accuracy of climate models, how does it change the fact that actual instrumental data shows a steady warming trend? This isn't an argument against global warming.

And again you parrot your notion that "warm is good, cold is bad". I'm all for things being conveiniently simple but it's absurd to suggest this of global climate. But I and others have already tried to get this through to you, why do you keep parroting arguments that have long been refuted? It leads to circular discussion.
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Offline frethack

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What proportion of global warming is attributable to humans?
« Reply #75 on: 07/12/2009 07:30:41 »
Quote
So the decline he was hiding was from temp data based on tree rings from 1960 onwards.

Its called the "diversion problem", and it is actually very important because its still unknown why measured temp records would diverge from tree ring records.  The problem presented is that we dont really know when this may have happened before because there are no instrumental records with which to compare.  Other than asking if this is the *only* divergence, you would also have to ask: If there have been more than one, is the current event a shorter/longer divergence than normal, or is the amplitude of divergence shallower/deeper than normal.  Is this a naturally occurring phenomenon (and if so, do all trees record it), or could it be an artifact of data processing and standardization (such as growth detrending).  Also, would any existing past events show postive divergence...where proxy data is higher than measured data.  Its not really known.  Tree ring chronologies make up a substantial part of the whole data stack in the Mann and Jones papers, so this is not a trivial problem.

Acknowledgment of the diversion problem wasnt included into the IPCC TAR until the final draft was presented, which didnt exactly leave much time for peer review.  Obviously, a majority of scientists believe that anthropogenic forcing outweighs natural forcing (though a slow shift is occurring now that records are more robust), and the UT paleoclimate department is no exception, but if I were to cite MBH98 (or any of the "hockey stick" papers) in a paper meant for review, my advisor would likely ask that I use a different temp reconstruction.

That being said, taking a few lines out of an email from a series of correspondences is somewhat shaky ground to make a staunch judgment on, but there is nothing wrong with a good independent review of the CRU/IPCC/NOAA/NASA.  If there is nothing to hide, then a little daylight should only serve to strengthen their argument.
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Offline litespeed

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What proportion of global warming is attributable to humans?
« Reply #76 on: 10/12/2009 01:50:19 »
Christopher Johnson - You wrote: "What proportion of global warming is attributable to humans?" The long and the short of it is that not one single human on the entire planet has even the smallest clue. Anyone who tells you otherwise is a knave. In fact, we may actually be in a global cooling event. [Research Sunspot Cycle 24].

Further, the Global Climate Scientific Community has aligned itself with the Global Climate Jackass Community and now deserves whatever the hell will befall it. I await in quiet anticipation.
« Last Edit: 10/12/2009 01:54:49 by litespeed »
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Offline peppercorn

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What proportion of global warming is attributable to humans?
« Reply #77 on: 10/12/2009 13:43:22 »
Quote from: litespeed on 10/12/2009 01:50:19
Christopher Johnson - You wrote: "What proportion of global warming is attributable to humans?" The long and the short of it is that not one single human on the entire planet has even the smallest clue.
Nonsense. There's a bundle of 'clues'. What there isn't is the sort of knock out blow that man is prominently responsible.

My view is the same as it would be if I found myself in the following circumstances. I have entered (for the first time) the engine house of a large, complex machine that appears to be slowly, but surely heading for a runaway condition. I also know that someone has recently (but long enough before to be the cause) moved one of the dozens of regulator valve controls to a new, higher setting. At this stage I can't be sure that the adjustment is the cause, but I would immediately put the that valve back to it's earlier state & then see what happened next.

Is the CO2 issue not like this?


Quote from: litespeed on 10/12/2009 01:50:19
I await in quiet anticipation.
If you're waiting in quiet anticipation, there seems to be a fairly constant level of background noise emanating from your direction!
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Offline litespeed

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What proportion of global warming is attributable to humans?
« Reply #78 on: 11/12/2009 22:58:33 »
pepper - You are a good adversary. However, you wrote: "...the engine house of a large, complex machine that appears to be slowly, but surely heading for a runaway condition."

I am unaware of any dangerous runaway condition. For instance, the planet was TEAMING with life at CO2 levels of 2,500 ppm. In recorded history we have Britain exporting drinkable wine in the Roman Era with CO2 level lower then now; [Incidentally, someplace I have a URL where-in one of the Low Countries is now celebrating its revived wine industry. It actually references ancient British vinticulture, and observes Britain has yet to recover its previous reputation.]

Warm is good, cold is bad.....
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Offline Madidus_Scientia

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What proportion of global warming is attributable to humans?
« Reply #79 on: 12/12/2009 05:45:48 »
Quote
I am unaware of any dangerous runaway condition.

From Wikipedia: http://en.wikipedia.org/wiki/Runaway_climate_change

Estimates of the size of the total carbon reservoir in Arctic permafrost and clathrates vary widely. It is suggested that at least 900 gigatonnes of carbon in permafrost exists worldwide.[21][unreliable source?] Further, there are believed to be around and another 400 gigatonnes of carbon in methane clathrates in permafrost regions alone,[22] and 10,000 to 11,000 gigatonnes worldwide.[22] This is large enough that if 10% of the stored methane were released, it would have an effect equivalent to a factor of 10 increase in atmospheric CO2 concentrations.[23] Methane is a potent greenhouse gas with a higher global warming potential than CO2.

And the less ice there is the less sunlight the earth reflects.

There is also the effect ocean acidification has on phytoplankton which will reduce uptake of CO2 by the ocean.

The high temperatures also increase the risk of bushfires which release more CO2.

Quote
the planet was TEAMING with life at CO2 levels of 2,500 ppm

Were 6.8 billion humans part of this life?

Homo sapiens have only been around 50 thousand years or so. There is evidence to suggest CO2 levels have not been this high for 2 million years. You can't say what's good for life 2 million years ago will be good for life today.

If you're going to repeatedly regurgitate your long rebutted arguments i'll just continue to regurgitate my original rebuttals.

Quote from: Madidus_Scientia on 14/11/2009 23:00:53
It is not only the level of CO2 that is a problem, but the rate at which it is increasing. Slow increases like those that have occured in history give life time to evolve and adapt, and ocean chemistry to buffer against ph decrease, but at the current rate this will be alot more difficult.

http://www.abc.net.au/news/stories/2009/03/09/2510699.htm
Quote
Dr Howard says that over time, the ocean may be able to counteract acidity by dissolving accumulated shells of dead marine organisms on the ocean floor, thus raising ocean pH and its ability to take up CO2.

But he says this will take a long time and come at the cost of living marine organisms.

"The buffering mechanisms in the ocean are quite slow compared to the rate at which we are putting fossil fuel carbon into the atmosphere and into the ocean.," he said.

http://www.coralcoe.org.au/news_stories/coralfutures.html
Quote
“When CO2 levels in the atmosphere reach about 500 parts per million, you put calcification out of business in the oceans.”

http://www.sciencedaily.com/releases/2007/10/071017102133.htm
Quote
New calculations made by marine chemists from the Monterey Bay Aquarium Research Institute (MBARI) suggest that low-oxygen "dead zones" in the ocean could expand significantly over the next century. These predictions are based on the fact that, as more and more carbon dioxide dissolves from the atmosphere into the ocean, marine animals will need more oxygen to survive.


Quote
In recorded history we have Britain exporting drinkable wine in the Roman Era with CO2 level lower then now;

So what?

Quote
Warm is good, cold is bad.....

Quote from: Madidus_Scientia on 07/11/2009 13:04:07
And concerning the advantages and disadvantages of global warming (from http://www.skepticalscience.com/global-warming-positives-negatives.htm )

Advantages:

Agriculture
    * Bumper crops in high latitude countries like Greenland, Canada
    * Higher rice yields in Northern China
Health
    * Fewer deaths from cold exposure
    * Record profits for pharmaceutical companies
Arctic Melt
    * Shippers get an Arctic shortcut between Atlantic and Pacific
    * Access to North Pole oil (hmm, good or bad?)
    * Thriving mammoth trade
Environment
    * Greener rainforests due to higher sunlight levels due to fewer rain clouds
    * Animals in Greenland can graze longer
    * Save grey nurse sharks from extinction
Glacier Melt
    * Access to more mining areas as Greenland's glaciers recede
    * New extreme sport of glacier surfing (riding waves when chunks of glaciers fall into the sea)
    * Longer grazing for sheep in Greenland
Economical
    * Increased summer movie box office
    * Lots of work and money for lawyers (not sure which column to put this one in)

Disadvantages:

Agriculture

    * China's grain harvest will be cut by 5 to 10% by 2030
    * Africa's food production will be halved by 2020.
    * Decelerating tropical forest growth
    * Increased conflict over resources
    * Dislocate millions (with subsequent economical and military ramifications) - an estimated 50 million by 2010
    * Coral reefs are dissolving due to CO2 turning seawater acidic and bleaching due to warmer waters
    * Increase of wildfire activity
    * Water shortages in the Mediterranean, flash floods along the Rhine and summers so hot that nuclear power stations can't cool down, more than half of Europe's plant species could risk extinction by 2080 according to EU paper
    * Increased range and severity of crop disease
    * Encroachment of shrubs into grasslands, rendering rangeland unsuitable for domestic livestock grazing
    * Diminishing fresh water supplies for coastal communities
    * Decreased water supply in the Colorado River Basin (McCabe 2007)
    * Decreasing water supply to the Murray-Darling Basin (Cai 2008)
    * Decreasing human water supplies, increased fire frequency, ecosystem change and expanded deserts (Solomon 2009)

Health

    * Increased deaths to heatwaves (5.74% increase to heatwaves compared to 1.59% to cold snaps)
    * Increases in malnutrition and consequent disorders, with implications for child growth and development.
    * Increased deaths, disease and injury due to heat waves, floods, storms, fires and droughts.
    * Spread of malaria into wider regions
    * Increased frequency of cardio-respiratory diseases due to higher concentrations of ground level ozone related to climate change.
    * Spread of mosquito vectors and dengue fever in Singapore.
    * Spread of dengue fever throughout the Americas.
    * Increased pollen levels (due to more CO2) leading to increased allergies
    * Increased spread of flesh eating disease
    * More heart problems

Arctic Melt

    * Decrease in Arctic albedo, further accelerating warming
    * Loss of 2/3 of the world's polar bear population within 50 years
    * Positive methane feedbacks from mammoth dung (you can't make this stuff up)
    * Melting of Arctic lakes leading to positive feedback from methane bubbling.
    * Icebergs risk to shipping
    * Rising sea levels due to melting land ice over Greenland and Canada

Environment

    * Rainforests releasing CO2 as regions become drier (from the 'greener rainforests' study)
    * Encroaching deserts displacing tens of millions
    * Drying of arctic ponds with subsequent damage to ecosystem
    * Vanishing lakes
    * Tibetan plateau warming at twice the global average, so that all the glaciers in the central and eastern Himalayas could disappear by 2035 at their present rate of decline
    * Skinny whales (I always thought they stood to lose some weight)
    * Acidification of the ocean that violate EPA standards for ocean quality, threatening ocean ecosystems (eg - harming coral and plankton)
    * Threatened extinction of British shellfish
    * Gradual extinction of leeches (someone's gotta love em)
    * Dwindling penguin numbers
    * Disappearance of the low-lying island country Tuvalu
    * Disruption to New Zealand aquatic species
    * Oxygen poor ocean zones are growing (Stramma 2008, Shaffer 2009)
    * Increased mortality rates of healthy trees in Western U.S. forest (more...)
    * More severe and extensive vegetation die-off due to warmer droughts (Breshears 2009)
Glacier Melt

    * Flooding of low lying Asian rice fields
    * Water supply cut off for China and South America
Economical

    * Billions of dollars of damage to public infrastructure
    * Reduced water supply in New Mexico


So either you really really like Grey Nurse sharks, or you haven't really weighed up the pros and cons.
« Last Edit: 12/12/2009 06:10:34 by Madidus_Scientia »
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