cohenite,

Where does the IPCC say this ? Ie, CO2 increase from 1890 and 290PPM to 2014 and 400PPM; temperature increase of GAT 0.7C. Predicted temperature for next 100 PPM is from 1.5 - 4C.

What else does it say at that point? It may well answer your question. Or it may enable someone else to do so.

But here a few ideas:
(1) 1.5 to 4C seems more like the figure for doubling of CO2, eg

The IPCC Fourth Assessment Report summarized climate sensitivity as "likely to be in the range 2 to 4.5°C with a best estimate of about 3°C, and is very unlikely to be less than 1.5°C. Values substantially higher than 4.5°C cannot be excluded, but agreement of models with observations is not as good for those values."

http://www.skepticalscience.com/climate-sensitivity-advanced.htm

(2) Temperature rises so far have been affected by atmospheric aerosols (pollution) which hopefully will decrease in future

Hi Steele. I've put a link to the C3 discussion in the paragraph under the graph which previously linked to a larger version of the graph. Wrong link went in originally.

This discussion is amusing. First because it is not the main point of Viv's article, but those who can't find fault with the rest try and undermine his credibility with it. His main point is that increasing CO2 does not lead to more extreme weather - now more or less accepted by the IPCC.

Second, what the graph purports to show is that the effect of CO2 is logarithmic. Completely uncontroversial, but most people don't know this fact.

Third, the point about the alleged negative impact of CO2 at the beginning of the graph is as bad as any of the maths in the graph. All it shows is that while CO2 was increasing temperature was decreasing.

Fourth, the graph is no worse than many of the graphs I've seen that purport to show a direct relationship between CO2 and temperature increase. As most of the increase in temperature is caused by forcings, so temperature increase ought to be greater than CO2 increase, but no-one comments on that.

GrahamY,

I suggest you re-read Viv's article. The graph, and what it is alleged to show, is certainly the main, if not the only, point on which any information of a scientific nature is given, on the first page of the article. It's perfectly good sense to observe that, given
(1) the false suggestion that the graph is from the NOAA, and
(2) the fact that no-one who tries to fit a sixth-order polynomial could possibly be taken seriously,
one should prefer sources of information which don't bear such obvious signs of unreliability.

It also indicates, more importantly, that OLO's editorial standards require nothing more than that the author of an article can in fact write.

And I'm certainly not one who "can't find fault with the rest" of the article, though the "fault" I find is that, with one exception, he gives no sources for any of the facts he states. So the reader is certainly justified in taking no notice of it (given the wealth of material available on the subject).

On GrahamY's second and third point, he can't have it both ways. Either the graph shows something about the effect of CO2, or it is so affected by other sources of variability in the temperature that it doesn't. As several posters have pointed out, obviously the latter is correct, which means that trying to fit a curve to the graph shown is crazy.

Further on GrahamY's second point - since the graph is of _changes_ in temperature versus CO2, one wouldn't expect it to look like the curve at http://wattsupwiththat.files.wordpress.com/2010/03/co2_modtrans_img1.png (which is somewhat like a logarithmic curve), but like the derivative of that curve. That it vaguely resembles the graph linked above is pure coincidence.

And the sixth-order polynomial is in effect a seventh-order polynomial. Though it's hard to argue that that is sillier than fitting a sixth-order polynomial.

I've no idea what his fourth point means, but am curious.

Dear GrahamY,

Look I get that Viv is probably a great bloke, you may well know him personally, but ultimately he is a 'climate enthusiast' as is Cox and also Flannery.

There is absolutely nothing wrong with being an enthusiast but the rest of us are a little more cautious with their offerings because we know that very enthusiasm can sometimes trip them up. It has done on this occasion.

The very first post expressed confusion about whether the graph was from NOAA. The National Oceanic and Atmospheric Administration is not made up of enthusiasts but rather actual climate scientists. Their research rightly holds significant weight in discussions around AGW.

Ultimately it is a question of probity. Should a graphic that through incorrect and inadequate labelling is construed as coming from NOAA be withdrawn and altered in a way that removed any questions about its origins before being reinstated? Surely the answer must be yes, not just for the credibility of OLO but because it would be the right thing to do.

I know it, others here know it and I am confident so do you.

GrahamY I think you are wrong here.

1. The reason I have criticized the figure is because it occurs early in the article, is so utterly wrong and is the only bit of support that Viv references. All the other claims are just opinion with no reference to where the supporting data is. For the one claim where there is supporting data, Viv's claims fall at the first hurdle. Why should I accept any of the unreferenced claims as true?

2. The graph does not purport to show the effect of CO2 is logarithmic. There is nothing logarithmic about the graph, the plotted trend line or the underlying data used. Indeed the graph title states it is a graph of "Global Temperature Impact of CO2 Emissions Declines".

It is not even a graph of this. What it is is a graph of 30 year average global temperature differences divided by cumulative emissions since 1881. There is no rationale to plot such a comparison. Indeed, all you would get is that because the denominator keeps getting larger and larger, whereas the numerator gets larger less slowly, is a graph that will asymptote to 0. Do you think that is why that particular comparison was chosen?

3. I know why the data at the start of he graph is negative. However, this is supposed to be a graph of global temperature impact of CO2, go and read the title again. Under such circumstances, getting a negative value should have been a clear warning that the data was not showing what you thought it was showing. The fact that Viv, Cox and seemingly yourself have failed to recognize this provides no confidence that you would recognize another confidence trick if it was presented.

4. There are a lot if factors that impact on climate: not limited to what the sun is doing, aerosols, cloud cover, El Niño/La Nina.

Steele, I think you are far too generous. If the 'zero' is entirely arbitrary, then you cannot take quantitative values from it.

Anyways, love this little bit from cohenite:
"http://c3headlines.typepad.com/.a/6a010536b58035970c01a73d5ebffd970d-pi

I mean that's brilliant! Visible indisputable proof that CO2 cools!"

You are taking the piss right? Be careful in righting down sarcastic comments, as it's often difficult to tell when they are being made in print.

If you aren't , and you honestly think that is what those graphs are telling you, then I don't think anything more needs to be said about your ability to interpret graphs. We'll just http://www.picturesnew.com/media/images/facepalm-photo.jpg and move on shall we?

Also, when will you realise that the IPCC is saying exactly what you are clumsily attempting to say about the log 'decline' in effect? The RF increases as CO2 increases, but the RF per ton, will decrease.

So, in effect you are arguing a point with yourself. I think this deserves a http://static.fjcdn.com/pictures/Double_399996_1614105.jpg

Oh, and don't mention the booze again (the man upstairs doesn't like it).