You should read the whole article, crikey.
Zeke Huasfather writes about climate sensitivity being 1.2 C for a doubling of CO2 and that is called the climate sensitivity number. And the fact that CO2 is a green house gas isn't really under dispute although what the the actual climate sensitivity number actually is, is under a lot of disagreement simply because after some 25 years of climate research they still don't know what that climate sensitivity number, the number of degrees rise in temperature for the doubling of CO2 actually is.
And even the IPCCC is backing away from it's very high estimates of the AR4 and is back to about a figure of 3 C with a lot of climate scientists suggesting that it is below 2 C and maybe around 1.2 C where it's effect on the climate and it's ability to produce fed back effects becomes lost in the natural small scale noise of the climate variations.

As to the feedbacks from a warming created by CO2, well they just simply don't know and Hausfather more or less admits that.

The IPCC and the warmist scientists just claim that all feedbacks are assumed to be positive, they bootstrap up so the global temperatures just keep right on increasing until we finish up like Venus, a hellish ball of semi molten rock.

Well that hasn't happened yet after some 4.5 billion years.
And during that 4.5 billion years there have been periods where the CO2 levels were possibly as high as 5000 ppm or about 12 times today's levels.
Even during the time of the dinosaurs, CO2 reached close to 2000 ppm at times and the world hasn't burnt up yet.
In fact the opposite is the case. The Earth has been in some form of an ice age during the last billion years far more so than it has been warm enough for comfortable life.

No offence to you crikey as your intentions and your attitude are good and you are prepared to debate but we have been through this almost endlessly with every new brain washed CAGW believer who arrives on the forum complete with boots and spurs to do battle and convince the "deniers" just how wrong and ignorant they really are.

And if you read Arnost's last post in the AGW news thread you will get a glimpse of the zealotry and fanaticsm that has nothing to do at all with debating about the science but has everything to do with promoting a cult ideology where increasingly "the end" , evil as it might be as we see Africans forced from their ages old lands to enable carbon credits to be earn't by carpet bagging westerners and old people and the poor no longer able to afford the power to warm themselves during the cold of winter, "The end justifies the means" in the eyes of those that are global warming zealots.

"The end" being semi slavery beholden to a small fanatical, manipulative and cynical group who believe they have the right to impose their ideology and beliefs on the rest of mankind in the name of saving the planet.

Sadly all of those believers who show up here are the victims of what is now being called "The Merchants of Despair" the purveyors of the depressing and fear mongering CAGW ideology.

There is nothing uplifting or gives hope to the human spirit in the message the climate warming "Merchants of Despair" are now preaching to the world.

There's this paper for starters...

Positive Cloud Feedback

Changes in extratropical storm track cloudiness 1983–2008: observational support for a poleward shift

Abstract

Climate model simulations suggest that the extratropical storm tracks will shift poleward as a consequence of global warming. In this study the northern and southern hemisphere storm tracks over the Pacific and Atlantic ocean basins are studied using observational data, primarily from the International Satellite Cloud Climatology Project, ISCCP. Potential shifts in the storm tracks are examined using the observed cloud structures as proxies for cyclone activity. Different data analysis methods are employed, with the objective to address difficulties and uncertainties in using ISCCP data for regional trend analysis. In particular, three data filtering techniques are explored; excluding specific problematic regions from the analysis, regressing out a spurious viewing geometry effect, and excluding specific cloud types from the analysis. These adjustments all, to varying degree, moderate the cloud trends in the original data but leave the qualitative aspects of those trends largely unaffected. Therefore, our analysis suggests that ISCCP data can be used to interpret regional trends in cloudiness, provided that data and instrumental artefacts are recognized and accounted for. The variation in magnitude between trends emerging from application of different data correction methods, allows us to estimate possible ranges for the observational changes. It is found that the storm tracks, here represented by the extent of the midlatitude-centered band of maximum cloud cover over the studied ocean basins, experience a poleward shift as well as a narrowing over the 25 year period covered by ISCCP.

The shifted path and reduced extent of the storm track cloudiness is accompanied by a regional reduction in total cloud cover. This decrease in cloudiness can primarily be ascribed to low level clouds, whereas the upper level cloud fraction actually increases, according to ISCCP. Independent satellite observations of radiative fluxes at the top of the atmosphere are consistent with the changes in total cloud cover.

The shift in cloudiness is also supported by a shift in central position of the mid-troposphere meridional temperature gradient. We do not find support for aerosols playing a significant role in the satellite observed changes in cloudiness. The observed changes in storm track cloudiness can be related to local cloud-induced changes in radiative forcing, using ERBE and CERES radiative fluxes.

The shortwave and the longwave components are found to act together, leading to a positive (warming) net radiative effect in response to the cloud changes in the storm track regions, indicative of positive cloud feedback.

Among the CMIP3 models that simulate poleward shifts in all four storm track areas, all but one show decreasing cloud amount on a global mean scale in response to increased CO2 forcing, further consistent with positive cloud feedback.

http://www.springerlink.com/content/q0q837g3363q435g/

This article is a must read...

Earth's Energy Budget Remained Out of Balance Despite Unusually Low Solar Activity

A new NASA study underscores the fact that greenhouse gases generated by human activity — not changes in solar activity — are the primary force driving global warming.

The study offers an updated calculation of the Earth's energy imbalance, the difference between the amount of solar energy absorbed by Earth's surface and the amount returned to space as heat. The researchers' calculations show that, despite unusually low solar activity between 2005 and 2010, the planet continued to absorb more energy than it returned to space.

http://www.giss.nasa.gov/research/news/20120130b/

Nonsense CB, solar ouputs of various kinds are controlling both the poleward and equatorward shifts, and the so called AGW warming and cooling!
Folk just need to look deeper into it all.

Nonsense back at you BD. It's not the sun!

http://www.wunderground.com/climate/facts/sun_is_not_to_blame.asp

Must see video featuring Dr. Pamela Matson, Dean of Stanford University's School of Earth Sciences, and a senior fellow at the Woods Institute for Environment. Dr. Matson is the Chair of the Panel on Advancing the Science of Climate Change.

Stanford is one of the most prestigious universities on the planet. While many of our best and brightest high school students apply to Stanford, very few are accepted. But imagine you are brilliant enough to get accepted to the school and find yourself in one of Dr. Matson's classes and you tell her you "just don't believe in climate change." What do you suppose she would say to you?

Here is what she states in this film clip:

"Lots of people have said to me, 'Well, I just don't believe in climate change.' And my answer is this is not about a belief. This is about evidence. This is about observations. This is about an accumulated body of knowledge that tells us something about the way the world is working. We are having a huge footprint on the planet. So it is very important at this point that we begin to think about ways to produce energy to meet the needs of people, to produce food to meet the needs of people without having negative consequences on the climate system."

We can deny AGW all we want but if we seek to stake our denial on the firm ground of science, we will miss every time, even while we deny the fact.


Click

Science is evidence-based, not belief-based. There is a difference between being sceptical and being anti-science. Someone who is sceptical does the same thing as any other scientist – follows the scientific method, and goes wherever it takes them, without partiality or prior conviction. Being sceptical is not a label, just a way of looking at things. One comes to conclusions or convictions in this way, a counterpoise to having preconceptions. Other connotations of the words "sceptic" or "believer" may be found in circulation, but their actual relevance in this (scientific) debate is very much on the periphery and seldom addresses key points.

The anti-scientist (as in someone who believes what they do regardless of any evidence for or against) goes on a mission to find as many – what they consider to be – flaws as they can in scientific theories, without regard for the scientific process or their confirmation bias (partiality). To be open-minded to any evidence (that follows from proper scientific practices) is a cornerstone of science, and it doesn’t matter who we are or what our views. At the moment it seems much evidence supports global warming (climate change in another context), given by genuine experts in their field.

This is not a question of belief, but of evidence, as in it has little to do with peoples' values (or beliefs) outside of the framework of science.

To bring that evidence into question requires genuine evidence to the contrary, which means each step in the casual chain must be addressed and accounted for by research, investigation and analysis, and be verified within the field. Simply stating something is so is not sufficient – the idea is that scientific theories are predictive (or projective).

I do not believe a personalisation of this topic is reasonable, or even justified, and to that end some humour may be deriding. Blurring of boundaries between what constitutes science and what doesn’t may also be a catalyst for undesirable attention.

This topic can undoubtedly bring about heated discussion, which I prefer to avoid because of non-scientific (non-relevant?) information being brought in from other areas (disciplines), which may sometimes miss the point about having this debate. Pointing to others' or other organisations' fallacies without an acknowledgement of one’s own limitations and imperfections is also a recipe for criticism, whether due or undue.

A scientific debate, in a science thread, is about just that. It requires one to actively research without partiality information and ideas pertaining to a pursuit of understanding and learning. Presumptions and preconceptions are exempt to that extent. Background and experience may play a role, but if one is actively dismissing information based on prior conviction, the process can become mired in controversy.

I do not believe any one “side” ought to dominate this debate (although at times it may seem like it), and that includes drawing attention to information on the basis (perception) of acceptance rather than evidence.

My thoughts .

Cosmic, you are falling into your own trap when you say that

For about 4.5 billion years entirely natural forces have shaped the climate on this planet.
Every aspect of what we are seeing and experiencing here and now has been done and gone un-countable times over the aeons past on this planet and it has been entirely natural
And that includes very high levels of CO2,at up to at least 5000 ppm or 12 times at least the present levels of CO2 and life thrived and continued on.

Now the evidence that you seem to be relying on is an assumption that CO2 is responsible for the warming beginning in about 1970 if we take the warmist's criteria and then that warming slowed down to a non statistically important rate after about 1998 and which non statistically relevant low rate of increase in global temps continues on until today.

So that Catastrophic global warming actually lasted just some 3 decades, some 30 years from 1970 to 1998.
And on those 30 years of warming are based the entire claims of anthropogenic global warming.

In the science you are so fond of " Extraordinary claims demand extraordinary evidence to substantiate those claims" ,

There is NO proven, substantiated extraordinary observed evidence to support the claim that the 4% of the annual turn over of CO2 on this planet that is supposedly created by man's burning of fossil fuels is in any way responsible for the recent global warming.

There are numerous unverified and unvalidated computer models that are programmed to try and convince the citizenship that this is the case and there are numerous people and scientists who do a lot of arm waving and make claims that have no foundation in fact or science whatsoever.
But there is NO undoubted, observed, verified proof or"extraordinary evidence" that Anthropogenic CO2 is the cause and reason for the recent increase in global temperatures.

Such claims ned extraordinary evidence when entirely natural warming [ and cooling ] events both slow and rapid, have almost without number been a part and parcel of the Earth's climate for the 4.5 billion years of it's existence.

To quote the late Carl Sagan;

What counts is not what sounds plausible, not what we would like to believe, not what one or two witnesses claim, but only what is supported by hard evidence rigorously and skeptically examined. Extraordinary claims require extraordinary evidence.


Of "Extraordinary evidence" of man's role in global warming there exists not.

Ignore!

Not in any way an attack on you Cosmic.
Merely a dissecting of what was both in your post and what was implied in your post using Earth's known geological history of which there is a lot of sources to look at and which i am interested in.

And In those various comments I was laying the explanatory ground work for my conclusions which i again presented at the end of the comment.
You can't discuss something like this in a vacuum and without defining the boundaries of one's discussion and that was what I was doing from my perspective.
Nobody is trying to put word's in your mouth or interpret your comments in any nefarious way.

Far from it! I was replying in my own way, outlining my own understandings and beliefs of mankind's supposed contribution to the claimed anthropogenic warming.
[ and our own beliefs are the basis of our understandings and nothing you might like to say about the purity of science will alter human nature in that regard. ]
So rest easy.

Bold Added.

A paper I read recently explains the slowdown in warming from around 2000.

http://www.springerlink.com/content/348g07361627360x/fulltext.html

From about 1970, the concerns in industrialized nations about the adverse effects of SO2 emissions on human health and ecological vitality led to effective policies to reduce those emissions.

The flat or even somewhat declining SO2 curve and the rising CO2 curve subsequently produced a steep increase in global temperatures between about 1970 and 2000.

After the year 2000, SO2 emissions started to rise once more, primarily attributable to increasing emissions in China (Smith et al. 2011). The model shows an inflection of the temperature curve at about the year 2000.

Fair enough .

I don’t believe evidence needs to be extraordinary…evidence simply is what it is, and is interpreted a certain way. That might be accurate, or very inaccurate, but any interpretation is a matter of degrees within this field.

Nope!
The global climate has been controlled entirely by natural means for the entire 4.5 billion years of the existence of this planet and that covers an immense range of climatic conditions which have swung quite often, geologically speaking, from quite far out extremes like ice ages back to the very warm Cretaceous times or even warmer epochs.

It needs "Extraordinary Evidence" to be able to even remotely back the "extraordinary claim" that an entirely new force / phenomena; ie Man made forces aka increasing human released CO2 from fossil fuels of which increasing CO2 levels are still far, far below previous levels of CO2 in past geological times, is now being claimed to be changing the global climate in catastrophic manner and doing so in just an instant of geological time.ie; 30 years of claimed global warming.

And the range of those claimed anthropogenic induced changes are just a tiny fraction of the range in the changes the planetary climate has gone through down the geological ages.

In the light of the above, "Extraordinary Evidence" is required before this claim can have any vestige of validity.
No evidence, extraordinary or otherwise, yet exists to back this claim.

OOPS! deleted. double post!

Given that there are still polar ice caps, would you agree that the climate can swing again either way, and that the natural variation – if it is induced – could be more dramatic than expected?

If it is "induced" by mankind, it's not a natural change to the climate.

So far there is increasing but still to be proven, evidence that there are natural factors, ie; an increasing volume of papers on the solar induced influences on the climate, and that these changing solar influences,might also have have been the cause of the entirely natural and recent swings and changes in the global climate, as has always been the case over past geological time.

On a past geological time basis, with the caveat that both volcanic eruptions on a massive and long lasting scale and meteor impacts, both entirely natural, have also created very significant changes to the past climate.

Not sure where or why you are fitting polar ice caps into this? They just go along with and are shaped by and influence the changes in the long term global climate.

The whole global climate / oceans/ land / volcano/ extra terrestrial influences ; ie solar, meteors, galactic arm crossings, possibly supernovas and the extreme radiation from them and etc and etc have all shaped and changed the global climate down through the ages in an interacting and chaotic and completely unpredictable manner.
Compared to the scale of those phenomena any influences that mankind can possibly have on the global climate is to say the least puny and very tempory in the extreme.

One of the main problems with the whole global warming claque is their complete inability to stop gazing at their own navel as that seems to be about as far as most of them can see when it comes to the time scales of our planet's existence and the processes and immense changes and extremes that the global climate has gone through over the aeons past.
The planet, swarming with life is still here as is it's life forms in all their multitudes of species despite those immense climate traumas of the past times.

The "Merchants of Despair" the anthropogenic catastrophists, are incapable of selling any message other than that of despair and fear of the future and because of that their cause is ultimately doomed and soon to be forgotten.

Palaeoclimatologists would disagree with you ROM. They study the past in order to better understand future scenarios.

http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch6.html

http://en.wikipedia.org/wiki/Paleoclimatology

Geologists have amongst the lowest percentage of believers in anthropogenic global warming of all the science professions and that says quite a lot.

As a very senior geologist said; our profession is the study of the Earth's past climate found in the rocks of the geological ages.

And Scenarios even based on the past history, aren't predictions nor can they be as the future is totally unpredictable.
Scenarios are just that, just playing with ideas and nothing else.