A new time series analysis technique, Empirical Mode Decomposition (EMD), which has been successfully applied to nonlinear and nonstationary data, is used to examine paleoclimate cycles in the Pleistocene (1 Ma bp–20 Ka bp). The purpose of this study is to improve knowledge of the climatic significance of solar insolation. The results show that the eccentricity band signal is much larger than previously estimated, having an amplitude of about 1% of solar irradiance which is comparable to the amplitude of the precession and obliquity band signals. This finding implies the need to reconsider the role of solar radiation on the formation and maintenance of quaternary ice sheet cycles.