The regression pattern of lower stratospheric (85 hPa) water vapour anomalies on the low-pass (6-year) filtered PDO index (thick black lines in Fig. 5f) form the Natural CESM experiment.
The time series of lower stratospheric water vapour are low-pass filtered before applying the regression. The black contour lines show the explained variance in percent. Stippling indicates the 95% significance level, with autocorrelation effects taken into account. Maps were produced using licensed IDL (http://www.harrisgeospatial.com/ProductsandSolutions/GeospatialProducts/IDL.aspx), version 8.1.