Orbital Forcing of the Marine Isotope Stage 9 Interglacial

Milankovitch orbital forcing theory has been used to assign time scales to many paleoclimate records. However, the validity of this theory remains uncertain, and independent sea-level chronologies used to test its applicability have been restricted largely to the past ∼135,000 years. Here, we report U-series ages for coral reefs formed on Henderson Island during sea-level high-stands occurring at ∼630,000 and ∼330,000 years ago. These data are consistent with the hypothesis that interglacial climates are forced by Northern Hemisphere summer solar insolation centered at 65°N latitude, as predicted by Milankovitch theory.