Southern Hemisphere initiation of the mid-Pleistocene transition
Abstract
The mid-Pleistocene transition [MPT; between ~1.25 and 0.7 million years ago (Ma)] marks when Earth's glacial pacing switched from 41,000- to 100,000-year cyclicity. Here, we present a South Pacific hydrogenous neodymium isotope record tracking changes in deep ocean circulation spanning 1.5 to 0.5 Ma. This record indicates that the MPT was not triggered by Northern Hemisphere (NH) processes. Instead, the growth of Antarctic ice sheets to a critical size (~1.8 Ma) primed the climate system for the MPT, with iceberg release and melting transferring buoyancy out of the Southern Ocean. This iceberg-associated buoyancy redistribution ultimately reduced deep water formation in the NH, an observation supported by our data. Once the MPT was initiated in the Southern Hemisphere, its subsequent climatic changes were dominated by NH processes.
Fields of Study & Subjects
Geology and Paleoclimatology Research
Paleontology and Stratigraphy of Fossils
Geological formations and processes
Publication details
- Journal / source
- Science Advances
- Publisher
- American Association for the Advancement of Science (AAAS)
- Volume
- 12
- Issue
- 10
- Pages
- eaea6811–eaea6811
- Publication date
- 4 March 2026
- Language
- EN