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In identifying the PSA pattern as a possible contributor to these trends, the aforementioned studies looked through the lens of the variable/s of interest. For instance, \citet{Ding2011} performed a maximum covariance analysis to look at the relationship between central Pacific SSTs and the broader SH circulation (the 200hPa geopotential height). The second mode of that analysis revealed a circulation resembling the PSA pattern (and that brings warm air over West Antarctica), and atmospheric model runs forced with the associated central Pacific SSTs produced a PSA-like wave train. While this is certainly a valid research methodology, the result would be more robust if it went both ways. For example, when looking at rainfall variability in south-eastern Australia, an ENSO signature is seen when looking from the rainfall perspective (e.g. a regression analysis between rainfall over south-eastern Australia and Pacific SSTs) and a rainfall signature is seen when looking from the ENSO perspective (e.g. composites of months of strongly positive or negative Ni\~{n}o 3.4 index show large rainfall anomalies in south-east Australia). In other words, the proposed mechanism would be more robust if a climatology of PSA pattern activity displayed trends consistent with warming in West Antarcitca.  Given that our current climatological understanding of the PSA pattern is somewhat dated \citep{Mo1998,Mo2001}, this study will seek to present an update. Not only will it utilize a longer, higher quality reanalysis dataset than previous studies, it will also develop and apply a methodology that fully exploits the capabilities of the Fourier transform, as opposed to relying on a traditional EOF-based approach. This alternative methodology was adapted from a recent climatology of SH zonal wave activity \citep{IrvingSimmonds2015} and seeks to avoid the issues associated with the stationary nature ofthe  spatial EOF modes, which can be problematic when trying to capture phase variations in a wave pattern of interest. These issues are further compounded in the case of the PSA pattern, due to the degeneracy (North 1982) or near-degeneracy ofthe  PSA-1 and PSA-2modes  \citep[e.g.][]{Mo2000}. This updated climatology will provide new insights into the variability, propagation and downstream impacts of the PSA pattern, including its the role in recent high latitude trends.