329754.fig.002a
(a) 4 months
329754.fig.002b
(b) 5 months
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(c) 6 months
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(d) 12 months
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(e) Summation
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(f) Anomaly
Figure 2: The time series of sine functions, their summation, and calculated anomaly. Shown are the sine functions with periods of (a) 4 months, (b) 5 months, (c) 6 months, (d) 12 months, (e) summation of the four time series (a) to (d), and (f) anomaly calculated from (e). The total time record of these time series is months (the plots are to 60 months). The anomaly calculation removes the signals of 4, 6, and 12 months periods, whereas it retains the signal of 5 months period.