In the 1920s, Serbian scientist Milutin Milankovitch proposed that cyclical changes in Earth’s orbital eccentricity, as well as its axial tilt and orientation, shape global climate. Part of his theory — widely accepted since — is that the amount of solar radiation, or insolation, reaching high northern latitudes is a major factor in regulating global ice volume and albedo, which in turn control the strength of tropical monsoons. But in a new study, researchers suggest that instead of global ice volume regulating monsoon strength, it’s mostly the other way around.