We investigate the spectral properties of climatic times series derived from two recent ice cores in Greenland and East Antarctica. We find that the signals behave in a similar way in the high frequency part of their spectra. The rapid oscillations found in the GRIP ice core were closely correlated to Heinrich Events. A comparable spectral feature is detected in the Vostok ice core. We discuss the possibilities of connections between the two hemispheres and proper ice sheet oscillations in the light of simple oscillating climate models. ¿ American Geophysical Union 1995