Besoeker

That was exactly my point.
In a previous thread I said the same as you.
Hence my comment "Numerical data would be kinda useful.......... "

But JC claimed, based on that graph:
It was that specific point I was addressing. It is nonsense. You can't draw that conclusion from that graph.

Clippo

Allanon,
Wikipedia has a very balanced summary of Milankovitch cycles and links to paleoclimate.
In wiki’s words :-
Prof. Wunsch’s paper, which I’m sure you will have read closely, does highlight the so-called 100,000 year problem – basically, the insolation forcing due to the orbital position of earth is predicted to be small yet the 100Ka climate swings are the greatest. He does offer caution tho’ that sample size is rather small (6-7 observations) to make grand statistical summaries.

You will see from Wikipedia that 2 other researchers accept that insolation effect is low but other feedbacks amplify the weak intial warming.

The favourite other feedback is CO2 release from the oceans, ice sheets or melting ‘tundra’.

This is exactly the mechanism that most climate researchers now accept is the cause of the CO2 vs Temp. lag in the ‘lag’ graph.

Quite simply, Climate changes affect the Carbon cycle. Whether Milankovitch or little green men cause the initial climate change there will always be lags due to ocean responses.

In effect,by accepting the ‘swindle’ hypothesis, (that rising temperature drives rising CO2), one is acceping that CO2 is not a greenhouse gas – which is at variance with all scientific fact.

Whilst it is useful to study paleoclimates to derive modern models, Wusch’s paper is irrelevant to the current phase of GW since the great difference with the present is :-

For 650,000 years, possibly many millions, CO2 levels have not been much higher than 300ppm.

The ‘warming’ phase after glaciation is accepted to take about 5,000 years and thus the CO2 rise from 200 – 300 ppm is similar.

CO2 starts to increase after about 800 years and is thus thought to be the primary warming cause for the remaining 4200 years.

Currently, we are well past the 5,000 year warming period.

Neither temperature or CO2 rise inexorably thereafter, probably due to CO2 trapping mechanisms of which there are many.

In the present, CO2 evolution from about 280 ppm to the current 380 ppm has occurred in about 200 years and the rate is thought to be increasing.

The source of this has been categorically proved by isotope studies and other studies to be burning of fossil fuels.

Ergo,. Current GW is man-made – anthropogenic .

Feldoon

I love False Dilemmas, don't you?

"If you're not A, you're B!"

"If you're not for us, you're against us!"

Etc.

allanon

@Clippo,

Wiki was my starting point to learn about Milankovitch cycles.

I always read texts before I post links to them !

From Wiki regarding the 100,000 year problem:

The reference to [3] is Wunsch's paper. I therefore interpreted Wunsch's paper as doubting the relationship between climate and orbital forcing w.r.t to the above statement from Wiki.

From the paper's abstract (my bolding) :

Further on in Wiki:

All I am suggesting is that there are still unknowns at work regarding the initial mechanism for the termination of those ice ages.

Clippo

Allanon
I suspected as much ! – although I’m surprised you didn’t get an admonishment from Feldoon based on past performance. ( perhaps with his sad obsession, he's only selective with me !)

As I said, I’m sure you do. However, did you read the link to the Royal Society that I gave you a little while ago, when you were looking for independent research funded or promoted by the Queen? I’ve had no feedback from you about that.


Which is all summarised in my earlier comment and repeated following:-

You wrote:-
Aaaah, ----- the intellectual security & refuge in ‘unknowns’. I smell a sceptic not wanting to accept the truth.

No paleoclimate scientist would dare suggest that all the fine details of initial glacial termination mechanisms are understood. However, I would re-refer you to Wiki:-

Prof. Wunsch’s paper casts some statistical doubt on the Milkanovitch connection but the other 2 papers in Wiki offer some explanation. To be perfectly fair, why didn’t you note these also?

Furthermore, I repeat that the CH4 program’s inference that Temperature rise drives CO2 emissions is completely fraudulent logic – a fallacious argument I suppose Feldoon would describe it as.

Neither do any of the known factors driving any of the studied glacial terminations apply to our GW situation of today for the reasons I gave earlier.. Even Prof. Wunsch agrees that our current GW is AGW.

Finally, geological history is divided into Eons, Eras, periods & epochs/series. The most recent of these in the past were the Holocene & Pleistocene. In scientific literature now is appearing the term ‘Anthropocene’ to describe the period in which mankind has had an effect on climate. Opinion is naturally divided on exact dates but the 'coiner' of the term and many scientists say from the 18th century. But see http://en.wikipedia.org/wiki/Anthropocene for a discussion.

Feldoon

That's if they were trying to use correlation graphs as anything other than a suggestive.