2011-06-15 11:56:07Quirky Temperatures


I invite attention to an article by Tom Quirk published by On Line Opinion (OLO) and entitled The temperature trend is not as simple as Garnaut makes out.  It is at http://www.onlineopinion.com.au/view.asp?article=12177.

You may feel that his attempt to link global temperature to Pacific Decadal Oscillation to show that temperature since 1998 has remained flat (Fig. 2) is worthy of rebuttal.

I am not sure what the Pacific Decadal Oscillation is, particularly since his graph shows points which are far more than ten years apart.  What I do know, is that the conclusions reached in his article are nonsense.

Would any other SkS authors care to write a rebuttal or make a comment on the article at OLO?  

2011-06-15 14:16:26
Dana Nuccitelli
We have a rebuttal already for this basic argument. Do a search for "it's Pacific Decadal Oscillation".
2011-06-16 10:48:15


Thanks - and a good rebuttal too.

2011-09-05 01:46:05A summary of Quirk's crazy argument.
MA Rodger


My first 'contribution' to this Forum so I don't know if this is useful.

This article was written by an idiot with, for the right audience, enough dressing to sound like he's knowledgeable. It's not a PDO argument per say. It's so bad, I don't know what you'd call it. A Tisdaleism perhaps? Below a 300 word summary.


Professor Ross Garnaut (who?) relies on econometrics to examine global temperature record which is foolish. Using 10 year average temperature figures obscures detail that may be important. So Garnaut's findings are premature (whatever they were). We need my 'trend analysis' of different atmospheric variables to look for 'breaks' in trends. Oceanography shows the Great Pacific Climate Shift (GPCS) happened in 1925, 1945 & 1977. The oceans are very important climate-wise. Temperature (graphed) and CO2 (not graphed yet) & humidity (not graphed at all) all show 'trend breaks' in these years, 3 things with breaks is too much for mere coincidence. Water temperatures drives air temperatures, thus it drives humidity & (like a soda bottle) CO2.

Annual temperatures (graph shows 1925, 1945 & 1977 'breaks') suggest another 'break at the end of the 1990s. Does CO2 support this? A graph of annual CO2 (south pole) with straight-line trend presented. CO2 value minus trend value then graphed yields a U-shaped graph of “Residual Difference” which is approximated by 3 straight lines which cross in 1975 & late 1990s. “It turns out there is also a break in the humidity time series in 1975-6.” These 'breaks' are just on the GPCS date. The 1990s break in CO2 matches the suggested temperature break and ones in humidity & methane (no graph). Methane is driven up by dropping humidity. It has only been measured since the 1980s. “This is a a 4 way coincidence not random noise (temperature) event...” A cool phase beginning in the PDO perhaps?

PDO not understood yet. Not driven by CO2. One suggestion is changes in earth's rotational speed but we cannot forecast “these ocean changes.” Ocean surface temperatures imbalance CO2 making modelling complicated. It is complicated. Garnaut's work was poor, perhaps cherry-picking. “It” casts doubt on the usefulness of atmospheric models to forecast temperature if temperature trends (perhaps 'breaks') and the likes of sea level change are uncertain.

2011-09-05 04:51:27A developed version of Quirk's paper.
MA Rodger


Just sat down with a cup of tea thinking I'd set about rebutting this Quirk paper. Looking for his references I quickly came across a later Quirk paper, much refined, more graphical support, least squares to draw his lines (a ruler would be quicker chum), significantly changed conclusions & showing all the signs of a rewrite by another more sensible hand (some acknowledgements at the end may point to who). Having both in the public arena could be a blessing. The new-found paper i:-

Submitted to Advances in Meteorology on July 3 2011

Did the global temperature trend change at the end of the 1990s?


It is basically saying that something happened climate-wise in 1997 coz I can approximate some graphs with straight lines and they all bend in 1997. And also in 1977 (although methane wasn't measured then so isn't considered) and temperatures also kinked in 1925 & 1947 (as long as you look through squinty eyes). And these are all years the PDO flipped. Strangely, the paper has no data on the PDO.