Interactive comment on " Antarctic ozone loss in 1989–2010: evidence for ozone recovery? " by

Abstract

The manuscript presents a decadal time series of the polar ozone losses in the Antarc-tic winter/spring obtained using the passive tracer method. Analysis utilizes data from 12 ground based stations and several satellite instruments. The work is in essence an extension of their previous paper " Estimation of Antarctic ozone loss from ground-based total column measurements " by J. Kuttippurath, F. Goutail, J.-P. Pommereau, F. Lefèvre, H. K. Roscoe, A. Pazmiño, W. Feng, M. P. Chipperfield, and S. Godin-Beekmann; Atmos. Chem. Phys., 10, 6569-6581, 2010, which was limited to the years (2005-2009). The extension to decadal time scale improves the details of the annual variability and gives better picture on timing of the beginning, peaking and ending of the polar loss periods including useful visualizations and gives hints for the recovery discussion. The trend analysis included in this work is also an extension compared with the predecessor paper. They use by now already standard statistical model which C3327 ACPD 12, C3327–C3330, 2012 applies so called explanatory variables that help in attributing the observed changes to physical and chemical causes. This type of statistical models has been extensively used since late 2000's for global, NH and Arctic data. For the Antarctic research they have not been used regularly because the dynamical proxies that work so well in NH and Arctic have smaller role in a stable and extremely cold Antarctic stratosphere. To get a better insight to the ozone layer recovery issue they use a piece wise linear trend estimator or EESC for spring time total ozone data with tipping point at 1997. The third element of the of the work includes speculation of whether or not and when " the first signs of recovery " can be seen from the Antarctic ozone data analyses. The Antarctic ozone is of course one of the most widely covered subject in geophysics and consequently, it is very difficult to find and present new aspects on it. The main novelty here is the extension of Antarctic ozone loss time series to two decades and clearly the work advances the knowledge on the details of polar ozone losses time series. On the other hand, general conclusions are quite as expected from the previ-ous literature. Structurally, the manuscript organization is well done and description of the methods sufficient as well as referencing to previous literature. I leave the specific comments on the use of English language to specialists or native speakers but in my mind rephrasing expressions and changing wording at places would improve the read-ability. In addition to language improvements I would like to draw attention (at least) to the following points in case the manuscript will be published.