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Supplemental Material

2For Comparing the impacts of tropical SST variability and polar stratospheric ozone loss on the3Southern Ocean westerly winds by David P Schneider, Clara Deser and Tingting Fan.

45The experiments described in this paper enable two approaches to estimate the forced response to6ozone depletion. The first approach is to simply take the ensemble mean of the single forcing

7ozone sensitivity experiments. The second approach is to isolate the role of ozone forcing by8

differencing the ensemble means of Full Forcing and Partial Forcing experiments.

910The experiments described in this paper also facilitate the comparison of the responses to two

11

distinct ozone datasets, SPARC and WACCM.

1213

This appendix includes two figures that illustrate the zonal wind and temperature trends

14

associated with these two methods and two datasets.

15
16

The analysis includes comparisons of the simulated lower stratospheric temperature trends over17

Antarctica with corresponding trends in the ERA-Interim reanalysis. To assess the reliability of18

the ERAI data, we compared timeseries of anomalies from ERAI with a compilation of upper-air

19

temperatures from Screen and Simmonds (2012). This comparison is shown in the first figure

20below.

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23

Figure Captions for Supplemental Material:

24

Figure S1: Timeseries of (a) SON and (b) DJF seasonal-mean temperature anomalies at 100hPa

25

over Antarctica in ERAI (red dashed lines) and data from Screen and Simmonds (2012; hereafter

26“SS12”) (black dashed line). The SS12 data are an average of timeseries from eight stations on27

the Antarctic continent with long radiosonde records, included in a number of homogenized28

datasets described by SS12. The ERAI data were integrated over 65°S-90°S, and spatially29

averaged using cosine of latitude weighting. Trends in the timeseries during the 1979-201030

period of overlap are -0.10±0.19, -0.17±0.27, -0.10±0.05, and -0.12±0.05 °C/year for ERAI-

31

SON, SS12-SON, ERAI-DJF and SS12-DJF, respectively.

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33

Figure S2: Latitude-height plots of DJF zonal-mean zonal wind (left column) and temperature

34trends (right column) for 1960-2000, comparing six estimates of the forced response to ozone.

35

Single-forcing results are from first two sensitivity experiments listed in Table 1. Differenced

36

results are obtained by differencing the ensemble means of the Full Forcing and Partial Forcing

37

integrations. Both methods were applied separately to ensembles using the SPARC and38

WACCM datasets. The single forcing combined results (panels a and b), the basis of most of the39

discussion in the main text, are obtained by averaging all 10 single forcing ozone runs. In all

40panels, color shading corresponds to the trend, black contours indicate the climatology, and41

green stippling indicates that the trend is significant at or above the 95% level. Note the non-42

linear colorscale. The zonal wind contour interval is 3.0 m s-1.

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Figure S3: Seasonal, lower stratospheric temperature trends over the polar cap (65°S-90°S,

45100hPA) during 1979-2011 in the single-forcing ozone runs. The thin lines are individual runs.

46The thick green and purple lines are the ensemble mean of the SPARC-forced, and WACCM-

47

forced runs, respectively.

4849
50

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Figure S1: Timeseries of (a) SON and (b) DJF seasonal-mean temperature anomalies at 100hPa
over Antarctica in ERAI (red dashed lines) and data from Screen and Simmonds (2012; hereafter“SS12”) (black dashed line). The SS12 data are an average of timeseries from eight stations on
the Antarctic continent with long radiosonde records, included in a number of homogenizeddatasets described by SS12. The ERAI data were integrated over 65°S-90°S, and spatiallyaveraged using cosine of latitude weighting. Trends in the timeseries during the 1979-2010
period of overlap are -0.10±0.19, -0.17±0.27, -0.10±0.05, and -0.12±0.05 °C/year for ERAISON, SS12-SON, ERAI-DJF and SS12-DJF, respectively.

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Figure S2: Caption next page10.1175/JCLI-D-15-0090.s1

SCHNEIDER ET AL.

Figure S2: Latitude-height plots of DJF zonal-mean zonal wind (left column) and temperature
trends (right column) for 1960-2000, comparing six estimates of the forced response to ozone.
Single-forcing results are from first two sensitivity experiments listed in Table 1. Differenced
results are obtained by differencing the ensemble means of the Full Forcing and Partial Forcing
integrations. Both methods were applied separately to ensembles using the SPARC andWACCM datasets. The single forcing combined results (panels a and b), the basis of most of thediscussion in the main text, are obtained by averaging all 10 single forcing ozone runs. In all
panels, color shading corresponds to the trend, black contours indicate the climatology, andgreen stippling indicates that the trend is significant at or above the 95% level. Note the nonlinear colorscale. The zonal wind contour interval is 3.0 m s-1.

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Figure S3: Seasonal, lower stratospheric temperature trends over the polar cap(65°S-90°S, 100hPA) during 1979-2011 in the single-forcing ozone runs. The thin lines
are individual runs. The thick green and purple lines are the ensemble mean of theSPARC-forced, and WACCM-forced runs, respectively.