Fig. S8.

Cross-wavelet coherence and phase relationship of the FB-δ¹⁵N and benthic δ¹⁸O at MD972142. Squared wavelet coherence between two time series was computed using the methods proposed by ref. 68. This analysis identifies regions of significant (95% confidence) coherence and its relative phase in time−frequency space. The 95% confidence level against red noise was calculated using the Monte Carlo method and is shown as a thick contour that encloses the significant sections. The light shading represents the COI, which ensures that the edge effects are negligible beyond this point. Black arrows indicate the relative phase relationship between the two time series, with in-phase pointing right, antiphase pointing left, benthic δ¹⁸O leading FB-δ¹⁵N by 90° pointing up, and benthic δ¹⁸O lagging by 90° pointing down. The different records have been interpolated to an evenly spaced time series of 2 ky before the spectral analysis of the data. A lag of FB-δ¹⁵N relative to benthic foraminiferal δ¹⁸O is observed especially in the four most recent terminations, as indicated by the direction of the arrows over the past 400 ky at the dominant 100-ky period.