Reply to: Climate Research

[BlasterBates]

And if this happened then it would certainly be noteworthy. I'd be interested in a link (to the actual analysis of the models) if you have one. I have to admit that I don't really know much about the individual models or how they have been validated. I only know how I would do it.

Here's a paper on it.

A comparison of local and aggregated climate model outputs with observed data - Hydrological Sciences Journal

[EternalOptimist]

And if this happened then it would certainly be noteworthy. I'd be interested in a link (to the actual analysis of the models) if you have one. I have to admit that I don't really know much about the individual models or how they have been validated. I only know how I would do it.

fair do's

check it out

[RichardCranium]

Before we carry on, please define what you mean by statistically signficant? What p-value are you starting with?

That reminds me. Sorry, this is slightly off-topic but...

Indeed I find the maths fascinating. Brillo, I think you would enjoy "Understanding Probability - Chance Rules in Everyday Life" by Henk Tijms.

Scourer enjoyed it, and so did I. A very well written book and an excellent recommendation.

Those of you seeking Xmas present ideas and enlightenment on statistics would appreciate a copy.

Getting back on topic, I suspect there are still too many unknown variables to predict climate change accurately.

Right, as you all were with the

[doodab]

I was thinking more of the sad situation where a model based upon a small series is then back-validated upon the same small series, passes the test and then is proclaimed infallible. Then the sceptics come along and hindcast it against a much larger series and show that it is erroneous

And if this happened then it would certainly be noteworthy. I'd be interested in a link (to the actual analysis of the models) if you have one. I have to admit that I don't really know much about the individual models or how they have been validated. I only know how I would do it.

[TimberWolf]

Going empirical necessarily imposes a limit on what you can know, not least the limits of human perception.
So yes pragmatism is all very well, but it doesn't help with the real deep questions.
What Feynman said was not that he thought the why didn't matter, but he could see no way of finding that out and therefore that he was not going to worry about it.

Empiricism is used for testing theories, it's not the whole story. Prior to shaking off philosophic blinkers and shackles, philosophers would make something up and it was accepted as true, and that held up scientific progress for hundreds years.

[EternalOptimist]

Which scientist after the 19th century has ever claimed a model infallible?

Anyone who claims the science is settled is wrong, anyone who claims that our children will not know what snow is, whilst defrosting the car is a fool

[BlasterBates]

Lets see what the scientists say about models:

A comparison of local and aggregated climate model outputs with observed data - Hydrological Sciences Journal

We compare the output of various climate models to temperature and precipitation observations at 55 points around the globe. We also spatially aggregate model output and observations over the contiguous USA using data from 70 stations, and we perform comparison at several temporal scales, including a climatic (30-year) scale. Besides confirming the findings of a previous assessment study that model projections at point scale are poor, results show that the spatially integrated projections are also poor.

...paraphrased in "English".

Climate models are a heap of sh*t.

Which is why instead of mild winters, as predicted by the models, we're about suffer harsh winters for the next 20 years. I mean the Met office can get it wrong once or twice, but it is becoming a serious habit, and that isn't just the UK, that includes most of the Southern Hemisphere and the Northern Hemisphere.

Hands up anyone who thinks 2011/2012 will be a mild winter.

[sasguru]

Your sig is intellectually dishonest as you don't understand what statistical significance is.

HTH

[sasguru]

I was thinking more of the sad situation where a model based upon a small series is then back-validated upon the same small series, passes the test and then is proclaimed infallible.

Which scientist after the 19th century has ever claimed a model infallible?

[sasguru]

Science made progress when it shook off its philosophical roots and went empirical.

Going empirical necessarily imposes a limit on what you can know, not least the limits of human perception.
So yes pragmatism is all very well, but it doesn't help with the real deep questions.
What Feynman said was not that he thought the why didn't matter, but he could see no way of finding that out and therefore that he was not going to worry about it.

[kandr]

Science made progress when it shook off its philosophical roots and went empirical.

I think Religion/Superstition has been the major drag on Scientific progress but hopefully those things will die out eventually.

But if you feel the works of Socrates, Plato and Descartes to name a few were a load of rubbish and a waste of time then that's your opinion.

[EternalOptimist]

I never said the models were perfectly accurate,.......

I was thinking more of the sad situation where a model based upon a small series is then back-validated upon the same small series, passes the test and then is proclaimed infallible. Then the sceptics come along and hindcast it against a much larger series and show that it is erroneous

[TimberWolf]

Maybe so. But philosophy is asking deeper questions than science does. Although the west has been hugely successful at science and technology, real intelligence is still missing.

Science made progress when it shook off its philosophical roots and went empirical.

[DimPrawn]

So who thinks DimPrawn is on Wikipedia right now looking up p-value.

Thatis quite a high barrier and not usual practice.
Why did you pick that?

[sasguru]

0.03

Thatis quite a high barrier and not usual practice.
Why did you pick that?