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From Prof. Gillett's Web site (amazing what the right keywords can do in Google, I used - Stott Gillett Antarctica and "Nature Geoscience"):

http://www.cru.uea.ac.uk/~nathan/pdf/ngeo338.pdf

Have fun: gotta go trick-or-treating. I'm going dressed as a CO2 molecule and I'm going to hit a lot of the houses of liberals I know: that should scare them!

[Parts of the observed and simulated trend patterns are associated with an upward trend in the Southern Annular Mode (SAM) index, which has probably been forced by a combination of greenhouse gas increases and stratospheric ozone depletion. The pattern of temperature trends associated with the trend in the SAM consists of warming of the Antarctic Peninsula and cooling elsewhere1, but the effect on the observed trends seems weaker here than in previous studies, partly because we are considering annual mean changes rather than just summer and autumn, and partly because there was a maximum in the SAM in the early 1960s, making the SAM trend over the period considered here smaller than that over the 1969–2000 period21. After the SAM-congruent component of the observed temperature trends has been removed, residual trends show warming everywhere except for at the South Pole, making them more similar to simulated residual trends than the corresponding raw trends. The CMIP3 models simulate a SAM-congruent temperature trend pattern that is weaker than that observed, owing to a smaller mean SAM trend in the models (0:05 hPa yr􀀀1) than that observed (0:06 hPa yr􀀀1) and a weaker temperature response to the SAM: the r.m.s. amplitude of the mean simulated temperature regression on the SAM is 79% of that observed. To objectively test for the presence of an anthropogenic or natural response in observations of polar temperature, we use a detection and attribution analysis to compare simulated and observed changes. Such methods, first developed to detect anthropogenic influence on global temperature, have more recently been used to detect anthropogenic influence on temperature on continental scales.] Looks like to me that they began by throwing out all the data that wouldn't fit their model. And none of it would work if the ozone influence data weren't cranked in to supplement the data.