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Fig. 5


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Smoothed monthly values of observed PF (top) as recorded by the author (PFJJ) and PF values (bottom) which are corrected for B0 and seeing (PFcJJ). The effect from the B0 corrections can readily be seen as a significant reduction of the seasonal variation of the hemispheric PF numbers. The seeing correction concerns both the removal of days with poor seeing and a baselining of all observations to Q = 3.5. Both figures show the hemispheric values (North “n” in blue, South “s” in red) and the totals (green).

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