Radical Rodent

If 2.7 offends you, try GISS.

Most of the curve fits a quadratic curve with internal variation of about +/-0.1C mostly due to weather variations.

Look at 1998 or 2010 and you will see that an El Nino can push annual temperatures up by 0.3C and La Nino can push it down by 0.1C.

In 1961 Pinatubo erupted. You can see a 0.1C cooling.

Look at the 5 year average. You can see a weak 11 year oscillation from the solar cycle, again around 0.1C

All of these are too small to explain the -1C change over the century.

Occasoinally you get larger kinks like the possible Heinrich eventbat 8.2kya, which Paul Dennis measured as -1.7C.

Over 100,00 years we oscillate through 5C between glacial and interglacials. Before the Ice Age started 2 million years ago climates tended to be 5C warmer than the Holocene. There has even been an odd Snowball Earth 10C cooler.

These are the variations we know well. None of them explain the 20th and 21st century warming.

EM, you need a longer list of alternatives.

Regarding variability in surface warming, there is something else to bear in mind. The heat capacity of the land and atmosphere is around 10^{22}J/K. In other words, increasing the temperature by 1K would take around 10^{22]J. If surface temperatures rise by 1K, the Planck response is 3.2W/m^2. In other words, in the absence of some radiative response, we'd be losing about 5 x 10^{22}J/year. Hence, an internally-driven warming event that increased temperatures by 1K, would be radiated away in a matter of months if there were no associated radiative response. Now, there can be a radiative response that might maintain internally-driven warming/cooling, but the physical processes that produce this radiative response are essentially the same as the feedbacks to anthropogenically-driven warming. Hence arguing for long-term internally driven warming and against anthropogenically-driven warming, is somewhat logically inconsistent.

Alan,
It seems odd that you would get so worked up about what EM said and yet have no real problems with what you've said in response. Again, nothing surprises me these days.

EM

The Marcott proxy reconstruction has a resolution of 3-400 years and is not adequate to resolve significant temperature shifts which are known from other proxy records with better resolution - for example it does not resolve the 8200 y event which was a large negative temperature excursion of 400 years duration and well documented from many sources. The artifice of adding a temperature record from a totally different source also reveals the author's motivation was probably more political than scientific and the reconstruction is not considered robust by many Paleoclimatologists.

An illusion of stability can easily be created by the use of proxy data with long wavelenth resolution - or indeed by using long period rolling means.

The glacial periods of the Pliestocene - far from exibiting equilibria are the most unstable periods in the recent climate record - showing frequent large upward and downward temperature excursions on short time scales and superimposed on a declining temperature trend. See my earlier posts on this thread

Another sufferer.

And you repeatedly turn up here because you wouldn't allow people the same freedom on your own blog.

And you have previously set up attack blogs against people like Anthony Watts, then have the temerity to come here complaining about people who have freedom to criticise.

Michael,
I don't think you've ever tried commenting on my site and I wasn't complaining about people having the freedom to criticise.

Michael hart

Alternatives?

What would you suggest? Don't forget the evidence.

Paleoclimate buff

Paul Dennis seemed unsure that his techniques could resolve the 8.2kya event. If Marcott et al did not resolve it either, perhaps it did not happen..

Michael,
I don't think you've ever tried commenting on my site and I wasn't complaining about people having the freedom to criticise.

Apr 11, 2016 at 9:11 PM | Unregistered Commenter...and Then There's Physics

Now you’re just sounding like a fratboy who can't understand why he can't bed cheerleaders. You have a history to live down. Why should I trust you, when you have clearly abused others and we can have a conversation here? I quite like the ambiance at Bishop Hill. Andrew Montford gives people lot of freedom of expression (and I occasionally use strong language that would not be allowed at most blogs). If you disagree, I'll bet dimes for dollars that your reply will appear here unless it is very offensive. I'll say it again, aTTP: Trust. You don't have much in the bank. You spent it.
Once lost, it takes a long time to recover and I don't see you making any effort to recover it.

Maybe someday you will summon up the courage to publicly own your opinions under your real name. That is something I decided to learn from Anthony Watts. What did you learn from Anthony Watts after you set up an attack blog aimed at him?

EM,

I don't know why I am bothering to write a response to your 9.41pm comment after following first your allegations then your ungracious withdrawal and conspiracy ideation about the hydrocarbon industry! As Alan has pointed out there is not an iota of evidence that the CRU emails were 'leaked' by any university staff. Neither do I take kindly to your risible attempt to slur by innuendo. You have no idea what was going on at UEA in November/December 2009 nor what my meetings with the police were about, nor meetings any of my colleagues may have had with the police. As for the newspaper reports they bear little resemblance to the truth. You live in your own little world and don't read with any degree of comprehension.

I did not say that isotopic techniques could not resolve the 8.2ka event. I was pointing out that (i) you should not take a measure of analytical precision as an indication of the minimum resolvable temperature, or of the precison with which we can determine temperature; (ii) our estimates of the temperature change are subject to an error because we don't have a complete understanding of the variables that contribute to the isotope shift in tufa deposits, namely the air temperature, groundwater temperature, precipitation isotope composition etc.

Following your behaviour and baseless allegations earlier today I'm now withdrawing from any further debate. It's clearly a waste of my time and I have much more worthwhile things to do with my time.

Mike,

We talking about desmogblog here? Or SkepticalScience perhaps? As an example of projection that comment wins the Award of the Week and here it is only Monday.

If I were to mention names like Soon, or Lomborg, or Ball, or Happer, or Plimer, or Salby, or even Pielke or Curry or Lindzen, all of whom have been maligned and insulted and had all sorts of accusations of misconduct made against them simply because they see climate science differently from the Faithful how would that sit with you, I wonder?

or bothering to engage in any sort of meaningful discussion.

And since you persist in telling us that you can't really be bothered with all our silly nonsense why not just butt out and leave us in peace?

Michael,

Trust. You don't have much in the bank. You spent it.
Once lost, it takes a long time to recover and I don't see you making any effort to recover it.

Maybe someday you will summon up the courage to publicly own your opinions under your real name.

What did you learn from Anthony Watts after you set up an attack blog aimed at him?

Paul Dennis

Paul please do not withdraw from debate here. If you do I will deeply regret calling EM out in the way I did. EM is not worth it. It has been made abundantly clear, and by many, that both of us are welcome here and our contributions valued. I also have learned much from your posts and will feel your absence.

Alan,

I didn't mean to imply that I would withdraw from commenting here. I mean to withdraw from direct debate with EM.

Paul Dennis

I mean to withdraw from direct debate with EM.

Me too!

It is a waste of effort - the man is suffering from an obsession.

aTTP, don't you co-author papers with some people well known to Skeptical Science? It seems strange that you want to distance yourself in this manner.

Paul Dennis

Follow the money.

Who benefitted from the UAE hack? Anyone with a financial interest in the failure of the Copenhagen conference. Fossil fuel companies top that list. This is logic, not paranoia or conspiracy ideation.

The police think it was a professional hack. Someone would have paid for it. The care to leave no trace and the lack of anyone claiming it support that view. There is also the quality of the analysis of the hacked emails. The way they were handled suggests professional lobbyists.

As Alan has pointed out there is not an iota of evidence that the CRU emails were 'leaked' by any university staff.

This is a logical fallacy. Absence of evidence is not evidence of absence. In fact, the evidence for a professional hack makes it less likely that they had inside help, but does not eliminate the possibility.

You might be better leaving this site. Without moderation, these discussions can get quite rough. It is not a place for the thin skinned.

About the 8.2kya event. We are back to the uncertainty question. You do not use statistical methods, so neither of us can quantify the uncertainties. Without knowing the standard deviation and 95% confidence limits of your data, how can you know whether the 8.2kya event is a real event or just noise in your data?

Marcott et al quote a temporal resolution of 300 years and 95% confidence limits of +/-0.2C. The 8.2kya event does not show in their data, at least according to paleoclimate buff. The temperature resolution is certainly sufficient, but the event may have been too brief for them to pick up.

What is the temporal and temperature resolution of your data?Can you demonstrate that they are good enough to be confident that the 8.2kya event is real? We have spent weeks going around this point and I never got a proper quantitative answer. Perhaps you could give me some numbers before you leave.

EM 12:13 "You might be better leaving this site. Without moderation, these discussions can get quite rough. It is not a place for the thin skinned."

EM thank you for demonstrating why everything you have ever posted here should be treated as unreliable. What kind of accusation do you consider to be unfair, if what you have said, and amplified on, above, is just 'rough'?

How much are you paid to post here? It is a logical question to ask, given your logic, as stated above.

You appear to be on a mission to discredit, by fair means, or foul, anyone who challenges your beliefs, and suggesting that someone else should cease posting here, could be construed as your misguided sense of victory.

All that money wasted on educating climate scientists how to communicate, and you have just demonstrated how climate science bullies people into silence. Congratulations.