Geronimo:

1. I'm well aware of feedbacks. But to get the total you have to add the +ve and -ve. The larger the -ve ones the lower the overall sensitivity. Sceptics like to claim a low sensitivity, and hence rely either upon the -ve feedbacks or upon discounting the +ve ones.

2. On your 200 months, you are cherry picking the start date.

3. I've not seen the rise of 1.16 quoted before here. Seems like spurious precision to me. Mostly people stick with 1C or 1.2C. True predicting future climate is difficult, but sceptics seem to want scientists not to try. Nice to see you describe some of your fellow posters as ignoramuses. I hope some of them will get as upset with you over that as you do with me using the banned word 'trapping'.

4. I don't know where you get your Arctic maximum from but it is nonsense. It is not even the end of the melt season so we haven't reached the minimum for the year.

Your story about Amundsen is interesting but insignificant. As for reconstructions failing, perhaps they should just have joined the cruise liner MS Bremen that passed through the Northwast Passage in 2006 (Wiki). And your 1922 article describes local conditions, not the whole Arctic.

5. As for you acidification and pH quibbles they are just more sceptic newspeak and have no relation to science.

5) Quibble is in the eye of the beholder.

http://hockeyschtick.blogspot.co.uk/2013/06/new-paper-finds-no-evidence-of-ocean.html
http://wattsupwiththat.com/2012/01/09/scripps-paper-ocean-acidification-fears-overhyped/

4) The Arctic was at its most robust at the end of the LIA. This was possibly an anomoly since much of the last 10,000 years was as warm or warmer than now. Do not try to quote studies that try to contradict a warmer globe if they rely on data from the Southern hemisphere as we are specifically talking about the North. The Arctic ice melted considerably in the first part of the last century but refroze somewhat during the 50s, 60s, 70s at which point the satellites were turned on. Turned on at the peak. Any melting we now see is probably normal for these temperatures. Wind also plays a huge role in ice melt since a lot of it flows out of the Arctic where it always did melt. Without hundreds of years of data it would be impossible to tell if what we've seen is normal, unusual or man made. Certainly with our short records this has been a cold Arctic summer and the ice gain between last year and this is impressive. Record breaking? It's easy to break short records.

http://ocean.dmi.dk/arctic/meant80n.uk.php

3) + 1) The problem with 'trap' is it suggests keeping something forever and 'newspeak and... no relation to science'. It's ok if you use it as shorthand but it really doesn't describe what's happening. The heat is being lost and gained all the time. Warming or cooling is the disparity between the two. It doesn't matter if you use 1.2C or 1.16C for doubling CO2, since both values are within our ability to adapt to. The questions should always be about feedbacks. To the best of my knowledge there are no proofs of what these are. Just guesses based on a very short range of data.

2) Cherries are a very popular fruit in climate science. One might say that it was cherry picking to start calculating feedbacks based on temperature data that includes the natural warming from an anomolously cold period, the positive phases of the two major oceans, a cut in western aerosols, high solar activity, substantial UHI and temperature data jiggery pockery. Something tells me the cherries are turning sour.

"1. I'm well aware of feedbacks. But to get the total you have to add the +ve and -ve. The larger the -ve ones the lower the overall sensitivity. Sceptics like to claim a low sensitivity, and hence rely either upon the -ve feedbacks or upon discounting the +ve ones."

You haven't the remotest awareness of feedbacks. You are taking the usual ignorant troll route of batting back facts you had no knowledge of before you started trolling. So let's ask you a feedback question, what is it that stops the positive feedbacks at any particular temperature. I'll be honest with you I don't know, and have asked many climate scientists for an explanation, without an answer from any of them, because, like you they pretend to understand "feedbacks". So, enlighten my ignorance what is it that limits a temperature increase to 3C, 4C or 4.5C. I'll give you a clue as to what the problem is:

(1) Increased temperature (from whatever source) causes an increase in water vapour

(2) Increased water vapour causes increased temperature

(3) Go back to (1).

Since you're an expert in feedbacks, how do we stop that?

Thanks MIke you've saved me 15 minutes of my life.

"On your 200 months, you are cherry picking the start date"

Of all the daft things you've said this is certainly the daftest. You don't have to cherry pick the period from which the temperature increase halted. The point is that your heroes told the world that CO2 caused an increase in temperature. We have 200 months when CO2 increased and temperature didn't. It's relevant because the theory tells us that CO2 caused late 20th century warming, so why didn't it cause warming from 1996?

1001, let me try to address your points more fully

1. I'm well aware of feedbacks. But to get the total you have to add the +ve and -ve. The larger the -ve ones the lower the overall sensitivity. Sceptics like to claim a low sensitivity, and hence rely either upon the -ve feedbacks or upon discounting the +ve ones.

Modern (last 3-4 years) estimates of sensitivity are all calculated, they don't rely on taking the model and setting some of the feedbacks one way and some the other. That was how they came up with the huge theoretical climate sensitivities in the past - by modelling. You would be right to say we were choosing certain magnitudes of negative feedback if that was how we were calculating climate sensitivity.

In recent times, we have enough data to actually measure it, i.e. the gross calculation of CO2 v instrumental temperature rise. All of the recent estimates of sensitivity have been based how measuring how much temperature we actually got bang for buck for our tonnage of emitted CO2. Since it was lower (sometimes much) than the older theoretical models, there must be a dampening, sink or negative feedback at play - we don't need to pin our colours to any particular one to be able to say "look, the sensitivity is small" - the question of what is making it smaller than theoretical is an interesting question for climate scientists to study, but we don't need to be alarmed any more. That's our point.

2. On your 200 months, you are cherry picking the start date.

There is a nugget of truth in that, in that this is the longest period you can find on the temperature graph that still gives a statistically insignificant trend. Any longer than 200 months you get a positive rise, since temperatures were rising rapidly during the 90s, so this is a no-brainer. For most values under 200 months, it goes flat or an insignificant fall in temps. The important point is that although 200 is cherry-picked to be the longest time (for rhetorical effect) - you can choose just about any value since then as the start and end date (outliers excepted) and you get no rise, e.g. from HADCRUT3

200 months - http://www.woodfortrees.org/plot/hadcrut3vgl/last:200/plot/hadcrut3vgl/last:200/trend
150 months - http://www.woodfortrees.org/plot/hadcrut3vgl/last:150/plot/hadcrut3vgl/last:200/trend
100 months - http://www.woodfortrees.org/plot/hadcrut3vgl/last:100/plot/hadcrut3vgl/last:200/trend

So although 200 months is a polemical device - the point is that temperatures have been on a standstill for a period of time - at least a decade. We don't know why, people are starting to guess at certain mechanisms. Warming may indeed have just paused and will restart again. The point is we don't know - and that is the point. We were told 10 years ago that the science was settled and inexorable rise was definitely going to happen. The whole point of us highlighting the pause in the temperature rise isn't to imply that it has stopped (it may be for some people) but just that science doesn't know so they need to stop it with the definitive statements. The models didn't model it, so they have been discredited as predictive instruments.

3. I've not seen the rise of 1.16 quoted before here. Seems like spurious precision to me. Mostly people stick with 1C or 1.2C.

It is spurious precision. I always say "around 1" or "1 to 2" - I'm not completely convinced that sensitivity is a static quantity, it may itself be dependent on other factors, but that's another argument.

True predicting future climate is difficult, but sceptics seem to want scientists not to try.

Not at all, we want them to try, honestly. But there's a difference between that and trying something hard, getting partial success and claiming that they are 97% sure that they have it right. And then when nature disobliges their predictions, we want them to admit they got it wrong before, and on that basis have the humility to accept that they may also be wrong this time too. We just want some honesty, that's all.

I don't know where you get your Arctic maximum from but it is nonsense. It is not even the end of the melt season so we haven't reached the minimum for the year.

Sorry, temps went back under zero again a couple of weeks ago, so you're dead wrong on this one. This year in particular we had one of the shortest melt seasons for a long time. Have a look at this link http://ocean.dmi.dk/arctic/meant80n.uk.php

5. As for you acidification and pH quibbles they are just more sceptic newspeak and have no relation to science.

Yes, it's a non-science reply to a non-science term "ocean acidification". It's a bit like saying your car brakes are "reverse engines" or that a drop of white paint in a pot of black is a "lightening pigment" - oceans are nowhere near acidic, the changes are towards the acid end of the scale, but only by a smidgeon, and a movement in that direction is technically acidification. Like 'trapping' - the term is used not for its scientific precision, but for its scare value.

Have fun.

- As a test of whether 200 months is a cherry pick I suggest that any conclusion about a time sequence shouldn't be altered by removing any one year and replacing it with the average of the time period. Try that with 1998 and see if your theory still works. One year shouldn't change anything if your conclusion is sound.

- Arctic at a record for 'summer'? Bizarre! Look at the PIOMAS volume charts and see how we stand relative to the long term average. http://neven1.typepad.com/blog/2013/08/piomas-august-2013.html

- Amundsen's brave transit in a shallow draught ship, hogging the coast with minimum depths of a few meters sounds like poor evidence for anything. I guess those guys trying to reconstruct the voyage should just have taken the MS Bremen cruise liner for the transit, eh?

- An ice free Arctic many times? The Arctic is a big place and checking it for a lack of ice seems beyond pre-satellite technology. Do you have any evidence (beyond stories)?

- Acidification is a banned word only for pseudo-skeptics. Everyone else uses it. Either that or "neutralisation". If the latter were used my guess is you would complain about that with the same vigour. Silliness like this in my mind gives the game away on any claims of being motivated by the science.

- TinyCO2 you clearly have a temperature record that you trust for the last 10k years. Which one is it?

- TinyCO2, do you have a scientific reference for your claim that the "Arctic ice melted considerably"? How do those melts compare with today. What were the estimated ice masses during summer in those years? Or is 'considerably' specific enough for you to draw a conclusion?

- TinyCO2, ice gain between last year and this was "impressive"? To whom? During winter there is no sunshine for 6 months, so are you impressed that the water froze? You try to sound scientific and then spoil it with things like this.

- Geronimo: not knowing about feedback? I don't want to go back to bickering about degrees to "prove" what I know. Like I said, assume I know nothing if it comforts you. The fact that nobody knows why historical temperature rises are constrained proves nothing. Are you suggesting that because we don't fully understand them that climate feedbacks don't exist?

- James, thanks for the thoughtful response. I wrote the above before seeing your text but I don't think what you write invalidates it.

It appears that 1001 may have left us.
I have been following this thread, and watching with interest at the way 1001 has failed to clearly answer any of the questions put to him.
For example, Mike Jackson asked: "I have been asking for empirical evidence (not "97% of scientists say ..."; not "the
models tell us ,,,"; not "it must be CO2 because we can't think of anything else") that the temperature is going to continue rising inexorably unless we reduce CO2 levels. So show me it."

1001 replied: "there's plenty of evidence, including rising temperatures, rising sea levels, melting Arctic,
rising ocean acidity, receding glaciers and of course rising CO2 levels and the inevitable 'trapping' (oops,
delaying) of heat. Take your pick."

Let's look at 1001's 'plenty of evidence' and ask him for a reply .

1. 'Rising temperatures.'
1001. Please provide the impirical evidence that shows any recent rising of temperatures have been soley or partly caused
by rising levels of Co2. And are not the result of natural variation. 'Simply to say that, temperatures have risen, therefore
it must have been because of rising Co2', is not science. It is purely supposition or blind faith.
Show the undisputed causal link.
Oh, and it may be worth pointing out that temperatures have remained static for 15 years while Co2 levels continue to rise. Though we are of course told that this is just natural variation, but when it starts to warm again, it will be our fault.

2. 'Rising sea-levels.'
Sea-levels continually rise and fall over the whole planet, and for a great many reasons. And have done so since time began. Please show me absolute proof that any recent rise is down soley to rises in Co2.

3. 'Melting Arctic'.
The arctic has melted to levels similar to, and beyond those of recent years, a number of times in recorded history.
Please show why any recent melting is down to rising Co2 levels and not other possible causes, a number of which are well documented.
By the way, the Northwest Passage was successfully navigated in 1940, 1941, 1942, 1944, 1957, 1969, 1977, 1984, 1988, and 2000. Was that all possible because of higher levels of Co2?
And if it was due to Co2 levels, what about the other years when this N.W Passage was not navigable?

4. 'Rising ocean acidity.'
The oceans of this world are all alkaline. They therefore cannot be 'rising in acidity', only 'lowering in alkalinity'. Using the correct terms can help to avoid confusion. To use the phrase 'Seawater is rising in acidity' is done soley to scare.
Seawater has Ph levels of between 7.5 to 8.5. The reasons the oceans are alkaline are due mainly to the vast amounts of calcium from animals and soluble chalk and limestone that has, and will continue to reach the oceans for millions of years. You would need to 'switch-off' these systems for the Ph of seawater to change greatly in the long term, let alone over the coming years.

5. 'Receding glaciers.'
There are now an estimated 170,000 glaciers in the world.The vast majority of these, around 95%, are on the Antarctic Continent where the average temperatures are -45C. Glaciers don't melt at those temperatures. As for the others, as many have been found to be growing as melting, 2000 found have recently been found growing in India alone. To simply say 'Glaciers are melting' and add nothing more, says nothing.

6. 'Rising Co2 levels.'
Any effect of Co2 on global temperature is a physical process and will obey the laws of physics every single hour of every day, 365 days a year, for ever. So if Co2 levels continue to rise, as they are doing, but temperatures have been virtually static for 15 years, then surely there must be other factors at work, such as:
1. That rising Co2 levels do not have a proven and clearly measurable affect on temperature.
2. That rising Co2 may have an effect, but is so small that it has very little effect on temperature.
3. Whether or not Co2 affects temperature, there are so many other factors which must control it, and certainly have as great, if not a far greater affect, that simply to concentrate on Co2 as being a 'demon' makes very little sense.

The world's biomass is presently at a very low level. This is primarily due to the recent very low levels of Co2.
In times past, when levels reached 7,000ppm and more, the biomass was far, far greater than today. Higher levels can only be beneficial to our wellbeing.
Plant’s eat Co2 and flourish when Co2 levels increase. For example: cereal crop yields can increase by up to 40% with a doubling of Co2. Higher Co2 levels also makes plants more drought resistant, allowing them to grow in places previously thought unworkable. Root-growth is greatly improved. Plants can also better withstand the growth-retarding effects of various environmental stresses, including soil salinity, air pollution, high and low air temperatures, and air-borne and soil-borne plant pathogens. Plants are the most important living organisms on our planet. To concentrate on their wellbeing would be far more productive than to spend time worrying about geologically low-levels of Co2 and there possible dire affects on us.

Over geological time Co2 levels have gone up, and come down. From a historical perspective, atmospheric CO2 levels of 400 ppm is not far off as low as it gets. In fact dangerously low. We are today barely above the Earth’s record lows. The Earth can sustain a much more green and fruitful environment if we reached CO2 levels of around 1000-1500 ppm.
We have recently (unwittingly) helped increase Co2 levels, and hopefully we can continue to do so, to get nearer to an ideal of around 1000 - 1500ppm.
Much lower than they have been recently and the world as we know it would end.

So what I would like to know is, exactly what is it you and your friends are woriied about from rising Co2 levels? The answer to that we rarely hear about.

Give me more co2 anyday!

1001 I'm sorry, I got the impression you followed climate science. Oh I forgot, you probably hang out with Dan Kahan who endlessly links to things to prove his points. Usually the links are to other posts he's made or spurious people surveys. Yawn. Well it's up to you now. The information is out there and counter information too, so there's no point linking to stuff because there's always another paper being printed. You are either interested or you're not.

We get it, you believe in CAGW and nothing we say will convince you otherwise. Now why not fess up about your CO2 footprint and we might think you really are interested in climate change and not just wasting everyone's time? Or is the theory of cutting CO2 too complicated for you too?

Martin A, Missy went beyond the pale with me by throwing up a person's religious beliefs as a reason to discount the science. I'm not sure where annoying stops and Trolling begins.

1001 is a good example of the topic heading. It has gone quiet out there. It mystifies the warmists and they blame sceptics. They wander into sceptic blogs and try to work out why. Obviously it's not because we have overwhelming evidence to convince people but because the warmist proof is equally vague. Both sides of the argument are bloody complex and won't be solved by grumbling about them here or Real Climate. Only time will tell.

As a chemist, I fully understand the spectroscopic properties of CO2 and other so-called GHG gases.

There is no doubt at all that they do absorb and emit IR at characteristic wavelengths.

I also understand black body radiation principles.

There is a massive and complex leap to say that this mechanism can lead to AGW.

Climate science appears to be Mickey Mouse Science based on a scant understanding of real science.

Mike Jackson, I don't suggest Geronimo use a new date, I suggest that he and you don't select a dataset and draw conclusions from it when changing one value in that dataset would invalidate the result. You wouldn't accept that
from a climate scientists so why practice it yourself.

I also find it strange that you lay the blame for the stupidity of people in boats at the feet of greens when it seems clearly to belong with the people in boats.

As far as evidence is concerned, if you can reject the mass of observations gathered by from satellites and other measurements in favour of a few old newspaper articles (or equate the two), then there is no evidence that can reach you. As I said earlier, you are all so inured to what goes around in blogs that you no longer know what is true and what is not.

As you say, we are done. I'll wish you all the best. And I hope you'll enjoy and be really impressed by the spectacle of Arctic water freezing over this winter all over again.

“Therefore everyone who hears these words of mine and puts them into practice is like a wise man who built his house on the rock. The rain came down, the streams rose, and the winds blew and beat against that house; yet it did not fall, because it had its foundation on the rock. But everyone who hears these words of mine and does not put them into practice is like a foolish man who built his house on sand. The rain came down, the streams rose, and the winds blew and beat against that house, and it fell with a great crash.”

And I think that explains nicely why the AGW phenomenon is actually a religion-substitute and our own little chunk of millenarianism madness which will be chuckled at by future generations. Oh look, they thought the climate was going to destroy them like a vengeful god - how primitive.

If anyone thinks the skeptic side is populated by bible-bashing fundies, explain why every major religion is backing the AGW message hell-for-leather. You're on the side of the 'angels' indeed.

Schrodinger's Cat:

"Climate science appears to be Mickey Mouse Science based on a scant understanding of real science."

I'll provide the links for you should 1001 return. First, the very basic;

Here

Now apply to Trenberth's Energy Budget;

Here

Which proves your point succinctly.

http://www.theguardian.com/environment/blog/2013/jul/15/uk-climate-movement-relaunch-2014

The heat will be turned up in the spring.... unless it's a bad winter. I wonder what people who donate to the RSPB or Christian Aid would think about their money going towards making their energy bills higher.