UC Irvine

In Table 2 of Elsbury et al. (2019), titled "The atmospheric response to positive IPV, positive AMV, and their combination in boreal winter," the number and frequency of sudden stratospheric warmings (SSWs) for various background interdecadal Pacific variability (IPV) and Atlantic multidecadal variability (AMV) states are incorrect. The reproduction of the Charlton and Polvani (2007, 2011) SSW algorithm used includes final warmings, which increases the SSW occurrences. Following correction, the number of SSWs decreases across all simulations. These results are printed in Table 2 below. The climatological frequency is 0.52 events per season in our control, lower than the frequency detected in reanalysis, but consistent with the frequency retrieved by Marsh et al. (2013), who also use WACCM4. With the correction, the percent increase in SSWs relative to control remains very similar, equaling 15% for 1AMV, 26% for 1IPV, and 33% for 1AIV (1AMV and 1IPV together). These figures appear correctly in the table. In general, these errors do not change any of the major findings of the manuscript. We apologize for the confusion the suspiciously high SSW results may have caused.