Fig. 1: Variations of sea surface temperature (SST) and subsurface sea temperature (subT) in the cores KX21-215 and MD05-252916 (left) and their power spectra using the multi-taper method (mid) and periodogram (right).
From: Forcing mechanisms of the half-precession cycle in the western equatorial Pacific temperature

a SST and (b) subT in the core KX21-2, c SST and (d) subT in the core MD05-2925. In the power spectra, the pink and blue curves indicate the 90% and 95% significance levels.