Daily chart

Okay, allow me to explain. You first come with all kind of questions that science has tried to answer. But you don't seem to have made any effort to find out what scientists have found. We have the internet now, and wikipedia is usually a good place to start.

You then conclude that humans are not causing climate change. You cannot have concluded that from your knowledge of the mechanisms which caused the climate to change in the past, or those that cause it to change now, because you know nothing of them.

Those past and present mechansism are not necessarily the same, so it is a fallacy to say that because climate changed before there were humans, therefore the current changes cannot be due to human activity.

If you had looked up some answers to your questions, you would have found that changes in the past were due to the interplay of factors like solar output, fluctuations in the earth's tilt, volcanic activity, ocean currents and fluctuations in atmospheric greenhouse gases (notably CO2).

This is all perfectly compatible with the current warming being due to human CO2 emissions that have increased the greenhouse effect (the blanket that keeps us all warm).

Previous changes in climate have been caused by changes in the angle of the Earth's axis, its orbit around the sun, and precession, called Milankovich cycles. (http://en.wikipedia.org/wiki/Milankovitch_cycles).

They are also caused by the positioning of the Earth's continents, volcanic eruptions, solar activity and one-off events such as asteroid strikes, to name but a few.

The correlation between concentrations of carbon dioxide in the atmosphere and global temperature has been proved beyond reasonable doubt.

We humans are releasing CO2 into the atmosphere and its concentration is higher now than for hundreds of thousands of years. The last time it was this high, the planet was several degrees warmer. Never has the level of CO2 increased so rapidly (as far as we are aware) as is happening right now.

I really don't see how this is so controversial – or why you're incapable of informing yourself on the topic.

Dude . . . you just got pwned by Sense Seeker and lghwalker at the same time. I bet the space between your ears hurts real real bad.

1. I'm not declaring victory, just pointing out that there are scientific papers which are showing weakening evidence, whereas the IPCC always starts every section of their report by declaring that evidence of AGW is getting stronger.

2. I've provided the link to sea level rise. Clearly, it's not accelerating.

3. The earth has warmed 0.8C since 1850. Accusing skeptics of cherry picking seems to be a kneejerk reaction. I've provided a graph showing a flat trend which lasted for more than half of the entire temperature record. Most warmists cherry pick the period only from the 1970s. 0.8C in 162 years is hardly catastrophic AGW, and is well below the 0.2C per decade that the IPCC basket of climate models suggest we will have, and that they claim to have considerable confidence in. Any chance of justifying the alarmist predictions of climate models, when there is no observational evidence to support this?

4. The ice age was clearly colder than what it is today, and mankind can't be responsible for most of the warming. If you're going to claim that the earth has warmed since 1850 whilst there have been substantial periods including the period since 1998 where there's been no warming, then it's inconsistent to point out that there have been longer cooling periods since the last ice age as proof that my statement that there's been natural warming since the ice age is incorrect. I didn't say that there's been continuous natural warming since the ice age.

All you've got is ideology. Happy to refer to your nonsense as climate ideology rather than science, if that's what you meant.

That the Greenland Ice Sheet (GIS) is not melting as fast as initial estimates plugged it is not weakening evidence for AGW- the ice sheet is still melting here, just not at a continuous rate, nor at the rate that previous studies .

The major flaw in your points 3 and point 4 is a misunderstanding of processes, and the timescales on which those processes work, that lead to global temperature change.

For instance, the end of the last ice age was most likely caused by an increase of high latitude Northern Hemisphere insolation and release of CO2 from the Southern Ocean, both of which led to ice-sheet destabilization and surface warming (see Anderson 2009 in Science, Shakun 2012 in Nature or I can send you many more refs). Northern Hemisphere insolation peaked around 11,000 years ago and has been declining since, and CO2 stopped rising around the same time. The important point here is the specific processes leading to the end of the last ice age have *no relevance* to changes occurring over the last 150 years, or the next 1000 for that matter.

You correctly point out that CO2 has a contribution to warming through the greenhouse effect. As I've said above, and as the IPCC illustrated, the only plausible mechanism to account for the observed 0.8°C warming since 1850 is the increase of atmospheric CO2 from fossil fuel use. You comment on the intervals of no warming since 1850- this is not evidence against the greenhouse effect, as is most commonly misstated- but rather that surface warming from CO2 is not instantaneous. Why? Because the heat from increased CO2 warmed the ocean instead of the land (the third curve in the Economist figure). As you can see, while the land has not warmed since 1998, the ocean has warmed remarkably.

The ocean cannot hold onto this heat indefinitely; it is eventually returned to the climate system and leads to surface temperature warming (this is the concept of "in the pipeline warming" from Hansen 2005 in Science). And that is the justification for the 0.2°C per decade warming in the IPCC scenarios- we will get a double whammy of heat inputs from increased CO2 in the atmosphere, plus warming due to heat currently stored in the ocean.

Thanks for at least providing a scientific theory. Unfortunately I have to dismiss the 1st paragraph as unprovable. In the 2nd paragrah, you're providing the ocean thermal inertia excuse for a lack of warming. There are several problems with this. Firstly, there is no accurate means of determining the missing heat in the ocean, since satellites are unable to detect subsurface heat which leaves the 3000 floating ARGO devices which are capable of diving to a relatively limited depth but obviously are randomly sampling the temperatures. Given the massive volume of the ocean, they're taking measurements of about 0.000000000000000001% of the ocean, which makes any attempt to say that the ocean is warming or not look dumb.

In the final paragraph, you're claiming that the ocean can't hold heat indefinitely and eventually will release the heat. This is the hypothesis that La Nina's are caused by the ocean absorbing heat and El Nino's when they release the heat. Since 1998, we've had 4.5 El Ninos and 5 La Ninas, so over the period it's been fairly evenly balanced. You also need to explain the mechanics which draws heat in to the ocean and allows it to be released. Given that CO2 levels have risen since the start of the industrial revolution (~1760), yet we had a period of no warming starting 90 years after the start, and lasting 82 years, it's difficult to see why the IPCC is so confident of 0.2C per decade going forward, in which they don't mention anything about the ocean thermal inertia theory. Their quotes are:-

"For the next two decades, a warming of about 0.2°C per decade is projected for a range of SRES emission scenarios. "

"Since IPCC’s first report in 1990, assessed projections have suggested global average temperature increases between about 0.15°C and 0.3°C per decade for 1990 to 2005. This can now be compared with observed values of about 0.2°C per decade, strengthening confidence in near-term projections."

This are 2 definite statements. They're saying that the models that they have confidence in predicted temperatures of between of 0.15C and 0.3C per decade between 1990 and 2005, which matched observed temperatures and that they're expecting this trend to continue going forward. No mention of a potential break in the trend due to ocean thermal inertia.

Well, if it was all provable we wouldn't need to have this debate! :) I agree that the climatological datasets greatly undersample the natural environment, but the ocean data that are available (Levitus climatology, ICOADS SST gridded fields) are certainly consistent with a significant increase in thermocline ocean heat content over the past 20 years. Despite the massive volume of the ocean, on this timescale only the thermocline component of the ocean (~20% of ocean volume) is really capable of storing heat, as deep ocean ventilation is (probably) too slow to significantly alter the balance.

The ocean heat storage hypothesis is not the same as the El Nino/La Nina hypothesis; changes between those modes involve translation of a warm water mass across the equatorial Pacific, but not a significant change in whole ocean heat content (during an El Nino event, eastern Pacific ocean warming is compensated by western Pacific ocean cooling, and vice versa for La Nina).

Relative to the no-warming periods, another wildcard is aerosols. Intriguing article by Booth et al. in Nature this year attributing multidecadal cooling of SSTs in the North Atlantic after the 1950s to sulfate aerosol emissions. It will be interesting to see what the IPCC next year says about last decade, and whether Chinese economic growth is associated with an increase in aerosol emissions that is offsetting expected warming. As you are aware, the climate system is multivariate in the extreme and quite a few factors can be at play at any time to muddle the CO2-surface temperature connection, aerosols and ocean warming just two examples of such.

You can at least see why skeptics have a problem with the AGW hypothesis. Basic physics of CO2 suggests only a moderate warming over centuries, which wouldn't be catastrophic. This is in stark contrast to the alarming predictions of the IPCC and media stories all of which are based on computer model projections, which have failed to come true so far. The warmist stance is that we admit that there are still uncertainties but taxpayers should fork out billions of dollars because if the models are right, we're in deep doodoo. The problem for us skeptics is that there are an infinite number of end of the world scenarios which could come true, and the fact that this is one of the more popular ones doesn't mean it has any more substance than the others. The observed data available and suspected cause don't trouble skeptics, because fossil fuels will have become too costly to extract long before the world faces disaster on current trends. The insistence that the computer model projections are right and the fact that global warming has become politically polarised are also not helping.

Correct. The question is not whether the earth is getting warmer (which isn't clearly shown from a trustworthy source). The question is whether human CO2 emissions are causing it. Everything else is a side issue.

The reason for the trustworthy source comment is just that I think many intelligent people are being misled. Politicians want power. Control of the world oil supply is ultimate power. Then they will send all the Christians to the Gulag. Progressives have been building hatred for them for decades now. That's where it's going.

You are so right and so wrong.Our imports of oil have been flat for decades. To decrease them (and total fuel usage,and emmisions) there must be an incentive to buy more efficient cars.etc. as well as the means to do it. ....the simple package outlined does that as well as boosts the economy. (What's good for GM is good for the country).

Study this page carefully, and then revisit your response: http://www.realclimate.org/index.php/archives/2005/01/the-global-cooling...

How about "willful ignoramusol"?

When it is hotter than usual, it's declared AGW.
When it is colder than usual, it's declared AGW.
When it is the same temperature as usual, it's declared AGW.

/Now cough up the money suckers.

You've yet to post anything remotely intelligent on this topic. The global cooling, if you'd bother to do ANY research, was largely due to pollutants (esp. sulfates) that reflected sunlight back to space before it had a chance to warm the Earth. That's why the effect became less and less as pollution controls came into effect in the 1970's. Just saw an article on the science news aggrigator phys.org that showed warming in the Southeastern US has lagged due to this very effect (a lot of coal use in the region).

I see you make lots of claims yet fail to provide a shred of evidence for it. But then, your "liberal baiting" tells me you have no interest in facts, just pushing your political agenda. Pathetic. Here's some evidense for you if you wish to actually know something...

http://en.wikipedia.org/wiki/Sulfate#Environmental_effects

The only ones pushing a political agenda are you global warmists. I see you warmists make a lot of meteorological claims without a shred of long-term geological/astronomical understanding. Global cooling due to pollutants? --How much of the expected change is the consequence of climate feedback loops, water vapor, clouds, snow packs? --and to what extent? --by how much will temperatures change over the next 100 years, --and where? --prophesy if you have enough faith! --has science determined whether there is a “safe” level of concentration of greenhouse gases? --and why do they believe that?

/Climate scientists are nothing more than political scientists with an agenda.

Doh. On a superficial level it is fun to read this exchange, but did the authors notice that the article says exactly nothing about causes of temperature changes, let alone attributing them to mankind?

"Doh" --indeed!

But the Economist doesn't have the background to explain the physical causes, although they sure know how to put the fear of Gaia in some of their loyal congregants.

Dude, STFU until you get an actual eductation. Right now, you're just running your mouth and spouting BS. The only reason for you to do this is either -

You're being paid to post this crap by "deniers" such as the oil/coal industries.

You're too stupid to understand the science, but you're a "conservative" and anything that "liberals" like must be bad/wrong.

Either way, you come off like a fool.

It's axiomatic, the global warm-mongers are very profane people, and never like it when metaphors are deployed on a topic that they have a political interest in.
"Here, read this link" --is all they can muster.
/You sound like a frustrated Algore.

Assuming you don't get your knowledge from Skepticalscience.com, you'll no doubt be aware that BEST only covers Land temperatures and isn't up to date, so can hardly be the elusive consolidated global land and ocean temperature data set. My comment wasn't about what this unprovable 97% believe, it was a comment that without a baselined set of definitions, this isn't science.

The prisoner's dilemma is a perfect set-up for the climate change debate. I would emphasize that the particular game we are playing is a one-shot version of the game because although we may make attempts at reducing emissions (Kyoto), because we don't actually feel the full bite of any failure (the bad part of choice two and also the Nash Equilibrium) until it is too late (if disaster strikes, to be fair to skeptics), we can not recognize the potential gains which become clear over multiple plays of the same game.

@SeattleToo: there will be economic costs (which varies depending on the severity of the ramp-up in pollution abatement, the costs in the future of doing nothing and the discount rate we use to solve the Cost-Benefit analysis) and they will hurt peoples standard of living in the short-term. To deny so hurts the argument.

@2Xvjpbp4uJ: To deny CO2 as a pollutant allows you to shirk a conversation. To CONSIDER CO2 as a pollutant allows you to be a meaningful part of it, even if in the end the optimal choice is to do nothing.

Right :)
You haven't read it either.
I won't get into my opinion of climate pseudo-science again. There's enough comments by me on the subject in this forum if you care to read them.

But... if you just read the Wikipedia entry on the book, you'll notice the first descriptive paragraph begins:
'Themes of the book include "Correlation does not imply causation" and "Using random sampling". It also shows how statistical graphs can be used to distort reality, ...'

I would really recommend reading it anyway.
Also "The Power of Supidity", by G. Livraghi, rather more recent.

FYI I am well educated in statistics. I was already aware that correlation alone is not sufficient to suggest causation. This, however, does not support your initial criticism of this daily chart. You are using a straw man argument - attacking the field of climate science for the simple error of "correlation implies causation", an error it has not made. There is much more depth to support a causative effect between climate change and carbon dioxide than such a simple argument. You are misrepresenting the field of climate science so as to more easily refute it.

Indeed this graph would not be appropriate in a technical article or when the causality of climate change is being debated, but this article is pitched at those who already believe in anthropogenic climate change. It does not attempt to convince of a causative relationship, rather it is highlighting some interesting trends.

Telling me to read some book or another is NOT a well reasoned argument. It is an admission of laziness, or a marker of ignorance. It tells me that either you can't be bothered to construct a reasoned argument or that you cannot. I understand that it is not possible to recapitulate an entire field in an internet argument, and at some point it may be appropriate to make a recommendation for further reading but before then you need to convince me that your argument has some merit. At this stage I have an entire body of literature detailing intricate models and exquisite data - and you, you have a straw man argument. I therefore will not be reading your recommended books.

Cheers.

"the previous generation of climate scientists announced the imminent next ice age, in the early 1970s" is a denier myth. See http://www.realclimate.org/index.php/archives/2005/01/the-global-cooling...
Al Gore, favorite target of the denier crowd, is irrelevant; he's not a scientist any more than most (all?) of the people (including me) blathering away on these blogs.

Denier myth: that is just silly! Clever move, on the rhetoric front however, I must admit that much.

In the 1970s I was in my 20s, living in Europe and I vividly remember reading about the coming ice age time and again (and actually being worried), just as now we are reading about global warming. Today I know a little more, and thus I am only worried about people like you who repeat, like a prayer mill, what others tell them.

Overeager climate meddlers are the real danger to our planet.

You seem to me to be in a state of denial; you can't accept that the world is not as gruesome as it pleases you. That takes your mission away. Think again, and try to find out who is profiting from your crusade. Think independently, for yourself.

Global coolin wsas a Denier myth? Are you nuts????

It was front page fodder at time magazine, newsweekn and every other rag from 1970 to the 80s!!!

Global coolin wsas a Denier myth? Are you nuts????

It was front page fodder at time magazine, newsweekn and every other rag from 1970 to the 80s!!!

Do you bother to read the material when someone puts evidence in front of you that counters your belief? The possibility of "global cooling" was nothing more than a blip in the scientific literature, picked up by the press for a very short stint (not "from 1970 to the 80s"), and now appears as a denier myth regardless of the facts.

I'm not nuts; I just read a lot.

Same response as to "justanonymous": do you read anything beyond denier blogs? Who do you rely on for scientific information? And I don't mean Al Gore, who is not a scientist of any sort, nor non-climatologist scientists who rage against evidence of AGW.

People need to get a grip on reality here. The climatologists are not talking about apocalypse (remember, NOT Al Gore) in the near term, just a hugely risky and uncertain future as we continue to pump GHGs into the atmosphere. Please do some reading of the actual science and projections before you spew all over these blogs.

In case you need a little help: scholar.google allows you to access much if not most of the peer reviewed literature on the planet. Try "anthropogenic global warming" to start; lots of hits, and I doubt there's a denier among them (sorry, I don't have time to screen the 88,300 papers for you).

"Think independently" indeed. What an insulting bunch of ---

You don't need to screen 88.300 papers for me, however it would have been a good idea for you to read at least the few sentences that I wrote here, to Steve Thompson first, then to you, before trying to lecture me.

I do not read "denier blogs" at all, actually I do not read any climate change/global warming articles except in the Economist; most of the rest is utter, complete crap.

I repeat: I do know two climate scientists personally; one of them in Boston/Cambridge, the other in the UK. They told me that they, and thus we all, do not have a clue as to the Earth's carbon cycle. One went as far as to say that we cannot even be sure whether increasing CO2 does warm or cool right now.

We do know that humanity adds CO2 and quite a few other things (the hysterics are oversimplifying it all to CO2) to the atmosphere in larger quantities than nature would on its own.

So it makes perfect sense to refrain from adding these gases/pollutants if it can be easily avoided, however, there is no need to go overboard and feel threatened by "huge risks" and start preaching and becoming a missionary.

I do not like to pollute in any way, just as no dog likes to shit in his own yard. I do not drive an SUV, I optimize my air travel, I changed my heating/warm water from gas to a heat pump six years ago because it makes economic sense, I do e.g. not throw used batteries in the household garbage, and so on, just to give you a few examples of what one can do without becoming hysterical and paranoid.

BUT I do NOT feel threatened, I do not feel that anyone has to be the savior of mankind, preaching and so on. I just told my kids and grand-kits, and now you and Steve Thompson :-)

Indeed, do think independently, stop being a missionary; missionaries have always been the scourge of mankind and always will be; best intentions paving the way to hell.

If you need a worthy cause, there are many others that are crystal clear and uncontested. But unless you are a climate scientist yourself, leave this field to those who know better, i.e. those who know they don't know - yet.

I read your posts, including this latest one. In short:

• You don’t read any climate science at all because you just know it’s “utter, complete crap.” Apparently you haven’t even bothered to look at a single reference in the climate science literature. Instead, you get your ‘science’ from the Economist magazine.
• You also rely on two unnamed and apparently unpublished (because they’re paranoid to voice their skeptical opinion?) climate scientists for your conclusion that “most of the rest is utter, complete crap.”
• One of the scientists you rely on says “we cannot even be sure whether increasing CO2 does warm or cool right now” which is contrary to theory and empirical evidence developed for over a century. Even real skeptics about anthropogenic GW (i.e., not deniers) acknowledge that the greenhouse effect is real. Why don’t you ask your climate scientist friend what temperature Earth would be if the greenhouse effect didn’t exist. Hint: lots colder.
• You call me a preacher and missionary because I suggest that you read some of the peer reviewed scientific literature before ignorantly spouting off.
• You want me to “leave this field to those who know better” even though you clearly haven’t done so yourself. I’m an experienced policy analyst; I synthesize the science by reading broadly in both the peer reviewed and popular literature. You can call me a preacher if you want, but I suggest that the simple fact that I absorb hundreds of authors’ work before coming to my conclusions (which contain a lot of uncertainty) gives my opinion about the subject more credibility than yours.

You are a hypocrite and a fool.

Written like a true lawyer :-) - half-truths, misrepresentations, contortions.

Climate science is in its infancy, yet overcrowded by non-scientists, who either have a hidden agenda or are in need of a cause. Apparently you earn your living meddling in the field. I don't.

Don't try to throw "peer reviewed scientific literature" at me. That does not impress me. I know the "system" at least as well as you do, the good, the bad, and its relevance in climate science.

The point I have been trying to make is simply to not let oneself be misled by hysterics and other activists and (ab)used by people with hidden agendas. There is no need to panic.

This position conflicts with yours, seeing a "hugely risky and uncertain future" if we do not do what you want, now!

Notwithstanding the above I am in favor of doing whatever is easily possible to help our climate and the environment. A few good habits go a long (enough) way.

I won't try to throw anything at you, least of all more facts; it's a waste of time. What does impress you? Being stupid?

You keep projecting "hysterics" on me. Where did I ever tell you "what I want"? You don't have a clue.

Throw MORE facts at me? So far I have not seen any, only "hypocrite", "fool" and "stupid". Just wishful thinking ... :-)

" ... Where did I ever tell you what I want? You don't have a clue. "

Precisely, that is what I call having a hidden agenda. You admit it yourself.

Why should I or anybody here trust or listen to you?

(To the other readers: indeed, SeattleToo - in over a dozen replies - lectures, reprimands and insults other commenters, but never says what he wants. However he expects us to be impressed by his pseudo-scientific claptrap; a "hugely risky and uncertain future" is awaiting us if we aren't.)

What, having the last word isn't good enough, you want two last words? And calling on "other readers" to condemn me!

OK, here's point one: I apologize for being so irritated that I used insults (although not directly if you read carefully). Nonetheless, I still think you're an irritating sot.

Regarding my "hidden agenda": your reading comprehension is not very good: I stated very clearly that what I desire here is that you read the science before expressing an ignorant opinion (and that's not an insult--ignorant means to ignore, as in ignoring the facts readily available to you). And that you respond to the content of my points, such as your reliance on two unidentified scientists expressing opinions contrary to 97% of the scientists publishing in the climate arena. Speaking of insults, what do you call "pseudo-scientific claptrap"? My summary and synthesis is accurate, and you produced nothing beyond arm waiving and your own insults in response. You are in fact intentionally ignorant and try to convince readers that because I am irritated and rude to you, my statement of the science is "claptrap" and yours is "truth." Talk about a lawyerly obfuscation!

I expressed no opinion or desire here ("agenda") as to what I think should be done about AGW. FYI, I think developing projections and scenarios to refine the range of likely outcomes of BAU and various options is the most important action we can take. Because the science and facts on the ground clearly indicate a "hugely risky and uncertain future." Much of the insurance industry gets it. Most people who deal with resource management (forests, water, wildlife) get it. What is your "hidden agenda"; that you prefer willful ignorance? Inquiring minds want to know; what's your "agenda"?

and we know what caused "global cooling" - pollution, esp. sulfates, that was pumped into the atmosphere until the early 70's by the developed (or 1st) world. The same sulfates that also caused acid rain, so it isn't a solution to the current warming. They reflected sunlight back towards space before it had a chance to reach the Earth's surface and warm it (and therefore the heat wasn't there to re-radiate towards space where CO2 could intercept it and redirct it towards the Earth again).

"the more you know"

oh god, are you insane. You're trying to tell us that the global cooling alarmism was caused by humanity too?

Read SeattleToo, he says that global cooling was oversensionalization by the media.

Can you crazy people just make up your minds? What was it? fake? or human caused? or denierconspiracy?

“... calling on "other readers" to condemn me!” Where do I ask for condemnation?

Just as I actually never denied that greenhouse gases may influence the climate. But that did not stop you from hitting me over the head with “what you remember vividly from the 1970s ‘is a denier myth’”.

You show a somewhat adolescent arrogance considering that you lack any direct experience with climate science. You believe you can compensate for that by “reading broadly in both the peer reviewed and popular literature” and come to the conclusion “my summary and synthesis is accurate”.

You mention peer reviews as if they were giving you a sort of papal infallibility. You have never peer reviewed nor ever been peer reviewed, otherwise you wouldn’t talk like that.

Quite frankly it seems to me that your judgement is that of the armchair dilettante.

Climate science is in its infancy, the conclusions you are jumping to “after reading broadly” are premature. You campaign against the imagined folly of what you present as delusional sots. At the same time you reveal your own foolishness, thinking you know all about it, while remaining ignorant of how your lack of knowledge distorts your judgement.

You say you are a policy analyst. From the way you interfere in the debate here you seem to hide behind climate science instead of just saying what you want. Instead of convincing us of the well-foundedness of your policies you seem to count on irrational fears to obtain approval.

As a policy analyst you should concentrate on the costs, benefits and risks of your policies, on the likelihood of obtaining the planned benefits for the projected costs. If you plan a policy to influence the climate than it should be irrelevant to you “where the climate comes from”. However, if you present a policy in that way (“let’s change the climate”), you will be laughed at. That is why you need to hide behind climate science (“alas there is no alternative to ...”).

I am not a denier, but I say that we do not know enough about the climate to rush into an action as colossal as trying to deliberately steer the climate in a specific direction. I am all with you when it comes to try - within reason - to diminish human interference with nature.

At present there are many worthier, more cost-effective and less risky goals to pursue with our limited resources.

"You show a somewhat adolescent arrogance considering that you lack any direct experience with climate science. You believe you can compensate for that by “reading broadly in both the peer reviewed and popular literature” and come to the conclusion “my summary and synthesis is accurate”.

I clearly have more direct experience with the science than you; by your own admission you don't read it. Until you challenge me on my conclusions with some facts and analysis, I'll maintain that my summary and synthesis is more accurate than anything I've heard from you based on very little.

"You mention peer reviews as if they were giving you a sort of papal infallibility."

Oh, as opposed to your single unidentified scientist friend? I am not referring to the peer reviewed literature as infallible, but it's the best we've got. What do you suggest we rely on instead?

"You have never peer reviewed nor ever been peer reviewed, otherwise you wouldn’t talk like that."

Aside from the fact that you're projecting claims that I'm not making, your assumption is incorrect; I have reviewed a scientific paper prior to publication. And while my policy and legal writing is not formally peer reviewed, much of it gets a thorough vetting by a number of reviewers. More importantly, I have worked extensively with scientists in a number of resource fields over the years (water quality, fisheries, forestry), and understand both the process and the content. You don't need a Ph.D. to be able to think critically.

"Climate science is in its infancy, the conclusions you are jumping to “after reading broadly” are premature."

The relationship between GHGs and GW is not in its infancy; Arrhenius published a century ago. The only major aspect of AGW that's in its "infancy" is the modelling of likely future climatic behavior. And what conclusions are you claiming I'm jumping to? Don't set up straw positions in place of my posts to knock down.

"we do not know enough about the climate to rush into an action as colossal as trying to deliberately steer the climate in a specific direction."

Is this the position you claim I'm pushing? You've got it backwards; humans are already steering the climate in a specific direction--more energy in the system, as The Economist's graph shows. My suggestion is that we need to consider the consequences of that direction and step back. Business as usual increasingly appears to be a road to ruin. Much of my "dilettante" reading is in the area of risk analysis and scenario building. The likely results with BAU get pretty ugly a few decades out. We are a selfish generation to foist the costs of those results on our descendants because we are too cheap, stupid, and/or arrogant to deal with them now. And we could have a better quality of life to boot.

"At present there are many worthier, more cost-effective and less risky goals to pursue with our limited resources."

As a professed "not a denier" I find your position in some ways more dangerous than flat out flat earther-like deniers. If the odds of something horrible happening are small, but the consequences great, don't you think we should be considering the investment in avoiding that future? How is it "risky" to address the need to reduce GHG emissions? What do you suggest we be doing instead? In fact, I don't think we are dealing very effectively with any of the major environmental/resource problems--population, climate, resource shortages, inequitable wealth distribution.

Two intelligent, well-educated people can look at the same set of data and come to vastly different conclusions with both acting in perfectly good faith. It does not necessarily mean that one of the two is either a stupid idiot, or an irritating sot or “dangerous”.

In a forum like this lawyerly tactics as in “... in short: ” or “... by your own admission” are not effective. You have to make an effort to understand the information other people provide as best you can instead of forcing to defend themselves against (deliberately) distorted assumptions.

In a TED presentation about a decade ago Stephen Petranek listed ten (probably peer reviewed :-) ) scenarios likely to wipe out humanity in this century (roughly, I do not remember the exact title). GW was not one of them; however, destroying our ecosystem was, though relatively low on the list, in 8th or 9th position. I agree and believe we actually have to deal with polluting the oceans and overfishing and destroying the rain forests much more urgently than with GW. And then some other Petranek scenarios are worth dealing with urgently as well.

David Deutscher, a scientist beyond any doubt, has made a speech at TED too where he also mentions GW (and no, he is not a denier) and comes to conclusions different from yours and mine. And he proposes a very interesting policy how to deal with it.

Last not least you will know Bjørn Lombork, another scientist, who should be close to any policy analyst as he advocates policy triage and brings a lot of common sense into the debate.

“How is it "risky" to address the need to reduce GHG emissions?”

The risk is - in my humble opinion - that we allocate limited resources badly. For a dollar invested in reducing GHG emissions we might well get less than for a dollar invested elsewhere, e.g. in stopping polluting the oceans and over-fishing.

It is not that GHG emissions do not exist, that GW does not exist, that GWG emissions do not contribute to GW. Reducing GHG emissions - today - is just a bad investment.

“In fact, I don't think we are dealing very effectively with any of the major environmental/resource problems--population, climate, resource shortages, inequitable wealth distribution.”

I couldn’t agree more!
But a crusade against GHG emissions alone, wearing blinders blocking out all others problems, is not the best answer.

"instead of forcing to defend themselves against (deliberately) distorted assumptions" Yes, and it works both ways here: I've never advocated "a crusade against GHG emissions alone, wearing blinders blocking out all others problems"

Petranek looks interesting (http://www.ted.com/talks/stephen_petranek_counts_down_to_armageddon.html); I'll watch when I have a half hour. David Deutscher I'm not familiar with and cannot readily find relevant sites; please post URLs. I've read some of Bjørn Lomborg (note sp.) and much of the commentary around him and his writings etc; I do not think he's credible on environmental and resource policy issues.

Of course GHG emissions (AGW) is not the only crisis; there is a whole area of study now on "boundary" problems with various resources. See e.g., http://www.stockholmresilience.org/download/18.8615c78125078c8d338000219...

I do not think it's a question of spending resources on GHG emissions reduction as opposed to spending them on something else, because our governance systems (apparently) are not capable of doing either in the time frame needed to avoid large increases in the risk (i.e., likelihood) of serious changes in our habitat from any of the threats. AGW probably won't "wipe out humanity in this century" but really unpleasant and costly consequences are highly likely, just as with population overshoot, peak oil, water shortages, phosphorus shortages, etc. And short sighted creatures that we are, looking only to this century ignores the lag time from anthropogenic GHG emissions, possible feedback additions (permafrost and Arctic Ocean methane is a huge one), etc. Whatever situation we have in 2100, it will probably not be the end of increasing instability in Earth's climate. Gaia does not recognize a calendar based on Jesus Christ.

Yes, I made up the blinders :-)
It's David Deutsch (not Deutscher, a spellchecker mishap), you will find him at TED.
I know that Bjørn Lombork is not liked for many reasons, but I still have to find fault with him. Read two of his books and found them ok; didn't read the latest one though.

Read a book. Maybe do some research into climate science? Historical data regarding climate and ice ages is explained in second year ecology classes.

Read a book. Maybe do some research into climate science? Historical data regarding climate and ice ages is explained in second year ecology classes.

Sir, it is silly to claim that The Economist is "sliding to the left" because you fail to fully understand the effects of global warming. If you bother to read the magazine you would realize that it does not operate on a political scale but is in fact very pro-corporate. This is good science despite your opinion and is important to consider for future risk management. A very apt topic for The Economist.

We know that basic physics doesn't imply that the world will warm alarmingly even if CO2 levels were to double from pre-industrial, so the risk is minimal, whereas the cost so far has been huge and as the AGW myth gets ever less credible, alarmists rhetoric demanding that we return to year 0 gets ever more worrisome. We can't run on fossil fuels forever, so there's a legitimate argument that we should fund research in to alternative energy, but this should be pulling research grants from no-nothing climate scientists who fill the internet with their anti-human bile.

I respectfully disagree. I do not believe climate warming is good science and I do not believe The Economist is pro-corporate.

Matter of opinion, I think both are self-serving.