Figure 2.

Holocene climate has been more complacent than that of the ice age. Morelet wavelet analysis (Torrence & Compo, 1998) of the NGRIP δ¹⁸O record interpolated at 50‐year intervals (Rasmussen et al., 2014). Blue indicates periods with little to no power in climate cycles of various wavelengths (y axis). Red indicates occurrence of pronounced climate cycles. Black lines outline zones falling outside (P < 0.05) the 95% range of 1000 Monte Carlo simulations of red‐noise time series using the same autoregressive model as for the NGRIP (AR1) data. White shading on the top corners is the ‘cone of influence’ where cycles become suspect due to edge effects.