A tropical Pacific role for the Mid-Pleistocene Transition

The Mid-Pleistocene Transition (MPT), between ∼1.5 and 0.9 million years ago, represents one of the most perplexing climate transitions yet discovered in oceanic benthic δ¹⁸O records. It is characterized by the change in the frequency/amplitude of δ¹⁸O, from 41,000-year cycles to 100,000-year cycles. Although the cause of this transition is still largely unsolved, there is an exceptionally strong bias in proposed explanations from high-latitude regions, possibly limiting a complete explanation of this puzzling climate phenomena. Here, I provide an alternative explanation of the MPT, with forcings originating from the tropical Pacific.