Middle Pleistocene glaciations in the Southern Hemisphere

Middle Pleistocene glacial records (774–129 ka) provide important insights into the drivers and tempo of Quaternary glaciations. However, such records are often fragmentary and incomplete due erosion over tens-to-hundreds of millennia—including by subsequent glacial readvances—and because research may yet to have fully documented their timing and extent. This review examines the current state of knowledge for the timing and extent of glaciation during the Middle Pleistocene across the Southern Hemisphere, particularly focussing on absolute-dated limits of terrestrial glaciation. Advances in dating techniques have helped reveal a multitude of Mid-Pleistocene glacial limits. The most well-defined reconstructions come from the Southern Andes of South America, where a long history of work on well-preserved, nested glacial limits has revealed one of the most complete and well constrained records of Quaternary glaciation anywhere in the world. Other detailed records of Mid-Pleistocene glaciation come from Tasmania and New Zealand. Combined with research from elsewhere in the Southern Hemisphere, the evidence highlights a consistent pattern of glaciation across the Southern Hemisphere during MIS 8 (∼300–243 ka). Some records also constrain the timing and extent of glaciation during MIS 12 (∼478–424 ka), MIS 10 (∼374–337 ka) and MIS 6 (∼191–130 ka), but not all glaciations are (yet) represented consistently in all places. The review supports work suggesting MIS 8 glaciation may have been driven by processes in the Southern Hemisphere and highlights key gaps worthy of further investigation.