Example time series for 2011 training period. The highest correlation for this fitting interval looks fairly similar to the 2012 fitting interval, but the 75–80 nm band has improved by 5%. This is evident as the model results no longer diverge from the observations at the edges of the time sample. Data uncertainties are a few percent, on the order of the size of the line used to plot. (a) Strongest correlation for 2011 training period, (b) weakest correlation for 2011 training period.