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Do you know why the original 11,000 year chart doesn't look anything like the 10,000 year chart in your link?

His chart is based on a single data set (the vostok ice core) for the majority of that period (plus modern temp records slapped on at the end, but it's not visible in the 10,000 year graph) which is not representative of global climate. Correlating proxy records with modern instrument records of temperature is not trivial either (which becomes far more apparent once you look at more than a single proxy record).

It's just cherry picked data to make a cheap political point. The scale of the vertical axis makes it very hard to see what is happening during interglacials, which is what we are in at the moment. If we were worried about an ice age arriving in the next couple of centuries the choice of scale might have some merit, to show how much colder it could possibly get. But we are worried about rapid heating, which that scale does a good job of hiding.

Why do people worry about the possibility of entering an ice age? That seems like the sort of thing humanity is much more prepared to survive.

We are more prepared to survive a 10 degrees drop than a degree and a half increase?

Not so much that a degree warmer is hard to survive, but the associated things that either come along with or are implied by global warming seem more damaging than colder weather and more ice, which we already know humans survived no problem ages ago when they migrated through Siberia and Alaska.

Possibly because it's a three word AGW denying blog post, and includes only from ice core data from Antarctica, whereas the 11,000 year data in the original post is compiled from multiple combined sources.

I'd hate to assume bad faith on the part of a climate change denier, but I can't help but speculate that the data source was chosen specifically because it made the point s/he wanted to make.

but I can't help but speculate that the data source was chosen specifically because it made the point s/he wanted to make

You don't thing that isn't happening among those who raise the AGW alarm? As the morally "right" position to hold, it even grants leave to do so righteously.

If only we had some sort of rigorous process for evaluating the evidence impartially, and coming up with conclusions, and constantly reevaluating those conclusions when new evidence comes to light.

Actually, I've heard of something like that - I think they called it "science". Hey, maybe we should put some "scientists" on this question, and see what they come up with!

I really wish there was some possibility of making any statement having to do with global warming without the polarizing positions: There aren't camps. You don't get to wear a jersey with the team colors.

Or at least there shouldn't be.

Science is very imperfect (does this really need to be stated?). Scientists are people. People are fallible, and people are quadruple fallible in groups.

In the face of an avalanche of information, history has shown over, and over, and over again that people have a tendency to essentially select data that fits the narrative, and to grossly overestimate the confidence of one's understanding of complex systems (we're seeing this already as the model of global warming veers wildly from what is actually happening with the world. This model was used, with high confidence, to pitch massive economic restructuring world-wide, but it has become evident that we as a species know less about how to model a world climate system than we imagine).

As someone else pointed out, this very submission has the egregious mistake that it compares granular data with 350-year smoothed data (which itself is taken from derived sources) -- being in the financial industry, I've seen countless cases where such shenanigans are used for very fraudulent purposes, but this is science because it fits the accepted narrative.

I'm not a "climate change denier", as an aside, though it's unfortunate that some cannot rationally reply to anything without such absolutism. I am naturally skeptical, however.

[I should apologize for getting hot under the collar, previously. I should have been much more circumspect in composing my reply.]

Granted, science is imperfect and all too human. I'd even go so far as to argue that it's deficient, dysfunctional, and perhaps even somewhat defective. But its products are orders of magnitude more credible than some random scientific-context-free graph by someone with no scientific reputation on the line. Most scientists have decades of experience and plenty to lose if it turns out they were sloppy or selective. By contrast, those doing anti-AGW advocacy can do "drive-by" FUD: they can use dirty data tricks because they don't need to convince a scientific community, there are negligible reputational consequences if they're wrong or they deliberately mislead, and their funding is secure regardless because either they're unfunded or it comes from murky or agenda-heavy sources rather than from competitive science grants.

What can be infuriating is when people equate drive-by FUD with, e.g., the products of the IPCC. This is tantamount to rejecting the entire scientific enterprise.

Do you have any freaking clue, whatsoever, how science works? Do you?

I'm pretty sure you freaking don't. Because if you did, you'd understand that everyone is out to prove each other wrong. And these aren't clueless denier I've-got-an-engineering-degree-and-I-read-some-articles-and-so-I-know-everything-tards that are doing the proving-wrong: these are people who've spent 30 years reading papers, talking with thousands of similarly knowledgeable people, and collecting and analyzing data. This isn't to say that they know everything or that they're always right or that they aren't subject to groupthink: those problems definitely exist. But what they're good at -- what they spend ALL THEIR TIME DOING -- is making sure that cherry-picking, and other stuff like it, isn't going on.

They're not bumbling fools who work at think tanks and therefore aren't at all accountable to their peers for the arguments they make or the things they say; these are people whose job it is to be right about things that very few people are thinking about, and to make sure that other people are right when they're doing the same. That's what they spend their days doing.

Please stop.

"And you are lynching Negroes". I'm not going to respond to this obvious fallacy beyond that.

There is no fallacy here, and your offensive, inappropriate retort has absolutely no place in this discussion.

You specifically decided to label one proposing an unwelcome data point as "climate change denier", which in an instant made your position clear, hence my reply.

>your offensive, inappropriate retort has absolutely no place in this discussion

I assume that means you're unaware of the historical meaning behind the quote: http://en.wikipedia.org/wiki/And_you_are_lynching_Negroes

The fallacy in question is also known as "tu quoque".

Edit: Also, it's interesting how often I point out a fallacy in someone's reasoning, only to have them say "there's no fallacy". In virtually every case, the situation was that they simply didn't see the fallacy. A better answer would be "I don't see the fallacy you're talking about."

Different data set. The 10,000 year chart is only Antarctic ice cores. The 11,000 year chart is a composite of a number of temperature records - tree rings, etc.

The 11,000 year chart is a composite. Funny how the data takes a wild change right where a completely new data source is included.

You realise that there is an entire paper in Science about how they synthesised the various temperature records? http://www.usu.edu/geo/physical/MarcottEtal_Science_2013.pdf

If you have something constructive to say about the methodology then let us know rather than making ignorant comments that tell us more about your political ideology than about the science.

Another comment notes of that paper:The Science paper says their reconstruction is smoothed and has low time resolution. They say it displays no variation at all on timescales <300 years, and attenuates even 1,000 year variations. Superimposing this with the 30-year Hadley data seems misleading, because it is on a very short timescale which is suppressed from the older data.

Let me guess, you're a Republican?

The OP made a perfectly legitimate observation. People should be skeptical of anyone trying to prove a point by showing a graph.

Thanks for posting a link to the actual science.

I suspect that "geological record" quoted is only one source - the graph in the original link is many sources combined.

Also, note the scales are totally different, and that the original link at least states sigma (uncertainty.)

Also, look at the scale of the Y-axis. One has a range of 1C and the other has a range of 15C.

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