Amplitude of fluctuations at different frequency ranges.

Amplitude of oscillations at particular frequency ranges derived from the partition of variances performed with spectral analyses, assuming normal distributions and applying the empirical rule. The amplitude of climate change for temperature corresponds to the estimated changes between 1906 and 2005 [51]. The climate change value for pH corresponds to the decrease in surface pH between 1750 and 1994 derived from estimated uptake of anthropogenic CO2 by the ocean [52]. Seasonal signals are derived from the long-term time series.