K.A. Tereszchuk and co-authors present a new PAN (peroxyacetyl nitrate) data product from the ACE-FTS satellite in a recent ACP paper. The estimated detection limit is 5pptv while the total systematic error contribution to the retrieval is approximately 16%. Comparison between the ACE-FTS product and measurements from the MIPAS instrument demonstrate good agreement, differing by no more than 70pptv. The data are used to produce zonal mean distributions of seasonal averages from 5-20km, with a strong seasonality being observed in the UTLS. Find the full abstract here.