Global warming in the Sunday Times mag

[landaftaf]

Re: Global warming and the media -

my 4th post earlier saying 'please read this' half way down -but its worth reading it all

another interesting site is here on this scientific discussion forum

 

[whipper_snapper]

Re: Global warming and the media -

OK, just done a very superficial google on this, and I am way beyond my expertise here but...

It looks to be very interesting. It appears that in the fine scale spikes - ie within the slow cycle - indeed temp does lead CO2. I cannot see it on the very long scale plots but it appears to be so.

So what is going on there ? The explanation I see is that the initial temp rise is indeed not caused by CO2, but by some 3rd factor. This temp rise causes an increase in CO2 levels which in turn trigger a CO2 rise and a positive feedback mechanism which is then responsible for the bulk of the spike until a new equilibrium is reached. I got that from here http://www.realclimate.org/index.php?p=13 (1st google hit, I know, not a proper way to do 'research')

For me that is a far from complete explanation, but clearly those ancient CO2 spikes were not caused by human activity, and if they were indeed triggered by, for example, increased solar heating, and if subsequent temp change was driven by feedback from that initial CO2 increase then we should still expect increasing CO2 to cause increasing global temperatures.

To me there is only one ‘if’ of any significance in the above. That is if CO2 is capable of providing a positive feedback mechanism. Well, isn’t that what a greenhouse gas is? Does anyone dispute that it can do this ? (That’s a genuine question by the way)

Looking at those ancient, slow, changes in CO2 and temperature, the obvious question is what is driving those cycles? It does not look random, the explanation that it is moving between equilibrium points triggered by temp changes and maintained by CO2 is rather convincing.

Now the question is, how robust are those equilibrium points ? I have no idea what might have constrained temp-CO2 over 650,000 years between the peaks that we see - I would love to know. An optimist might say that’s ok then the earth’s natural buffering will take care of it. The trouble is that from the evidence I see, we cannot hope for that. The reason being that
1. CO2 levels are today higher than they have been at any time over that period, so we are well outside the previously demonstrated buffering capacity.
2. The rise is faster than ever seen before, so we have no evidence that natural buffering can act that fast.
3. If we look further back, we do see periods when those equilibria were breached and temp and CO2 did stay correlated.

 

[landaftaf]

Re: Global warming and the media -

if you really want to read some comments pointing to the lack of substance to mans contribution towards GW

look here

 

[bedouin]

Re: Global warming and the media -

[ QUOTE ]

1. CO2 levels are today higher than they have been at any time over that period, so we are well outside the previously demonstrated buffering capacity.
2. The rise is faster than ever seen before, so we have no evidence that natural buffering can act that fast.


[/ QUOTE ]
Those are the two key facts and the truth is that no one knows the answer because we are too far removed from anything that has been observed in the last 1000000 years to have adequate data to model the future.

That should be the real debate at the moment.

The reassuring thing is that scientists have often in the past forecast doom and gloom on the basis on a linear extrapolation of non-linear processess so I am pretty sure the doom-and-gloom merchants are just as wrong as the flat-earthers who say it is not happening

 

[DavenHelen]

[ QUOTE ]
You complete and utter spanner.

The graph is INTENDED to illustrate the cycle. That's why it goes back so far and the recent increases look so STEEP. But didn't you notice the little spike in the last 150 years or so, which the temperature has yet to match...? Seem a little unusual? There ARE cycles, but the natural variance, particularly over such a SMALL PERIOD OF TIME, is NOTHING like the recent changes.

[/ QUOTE ]

Now go back and read what I wrote.....

You make an assumption that CO2 causes Global Warming and interpret the Graph accordingly. Take the Graph as a measure of 2 variables and it says what I said.

 

[landaftaf]

Re: Global warming - the ch 4 program is here

for those who are interested its an hour and 13 mins long - the full program

those who did see it might want to see it again - after all this palaver on here /forums/images/graemlins/cool.gif

 

[DavenHelen]

[ QUOTE ]
There is absolutely nothing in that graph that says anything except there is a very strong correlation between temp and CO2. That really is a fact.

[/ QUOTE ]

As an aside, there is a well known study in statistics which happened in Germany that showed an almost perfect correlation between numbers of Storks and number of Children born. Even with a perfect correlation you need to understand additional factors that may be a cause of the factors you are correlating.

 

[whipper_snapper]

Of course that is true. I have used sound statistics to show that the probability of supporting a given football team is determined by a single sex-limited gene. If you read what I wrote, I said that there is overwhelming evidence of an extraordinary correlation between CO2 and temperature. I did not say that one controls the other, but that remains a very distinct possibility. As you say, you need to look at the underlying proceses to distinguish cause from effect. As it happens, in this case there is a very well understood mechanism for a causal relationship.

 

[landaftaf]

did you view the recommended reading - and look at the video .... I do hope so as you did say you wanted more info

it states visually and verbally the graphical value of CO2 follows the graphical value of the temp by about 800 yrs. this looks like what happens on the graphs and seems logical to me, so is what I believe is the case.

it screws up the human effect theory about GW but hey - co-incidentally thats good as well isnt it /forums/images/graemlins/cool.gif

 

[whipper_snapper]

Yes I did. Please see my comments above on the lag.

Incidentally, I am right now in a very poor African country at a conference that touches on climate change. Ther are some 50 developing country scientists here - mostly agriculturalists and economists from Africa, S America and Asia . A UK -based speaker mention the C4 documentary and caused some amusement. Do you know how many of the developing country people here think that the 'global warmers' are a threat to them - not one. How many think global warming itself is a threat - 100%.

I think most people did not really understand the comments on the C4 documentary - just bemused puzzulement.

 

[merseamercy]

[ QUOTE ]
As an aside, there is a well known study in statistics which happened in Germany that showed an almost perfect correlation between numbers of Storks and number of Children born.

[/ QUOTE ]
Isn't that like finding a correlation between the number of cars on the motorway and the number of trucks on the motorway...? The cause in fact is quite likely to be the same, although I am no stork expert!

I don't think it disproves a link between CO2 and warming. You are being far too cynical (cynical, by the way, is not the same as objective, and science is not cynicism, so don't come back with that nonsense again). Perhaps you think it's fashionable.