Dryland dunes and other dryland environmental archives as proxies for Late Quaternary stratigraphy and environmental and climate change in southern Africa

Abstract The Namib Desert and the Kalahari constitute drylands of southern Africa, with current relatively humid portions latter having experienced periodically drier conditions during Late Quaternary. This study explores range dryland archives proxies available for past ~190 ka. These include classic geomorphological proxies, such as sand dunes, well water-lain sediments within former lakes ephemeral fluvial systems, lake shorelines, ramps, calcrete tufa at interface surface hydrological hydrogeological, speleothems groundwater hydrogeological records, hyrax middens. Palaeoenvironmental evidence can also be contained geoarchaeological in caves, overhangs rockshelters. integration records is undertaken aim identifying a (or number of) terrestrial regional chronostratigraphic framework(s) this time period because missing from Quaternary stratigraphy lexicon. Owing to lack long, near-continuous sequences these drylands, correspondence between nearby are explored basis parasequences build chronostratigraphy. Recognising modern climatological diversity across subcontinent, four broad spatial subdivisions used explore potential sub-regional parasequences, which capture climatic gradients, including hyper-arid west coast decrease aridity southwest toward north east. Desert, northern Kalahari, eastern fringes Kalahari. Terrestrial chronostratigraphies must start premise that climate-driven environmental shifts may have occurred independently those other locations diachronous compared marine oxygen isotope (MIS), serves global-scale master climatostratigraphy relating global ice volume. fragmented nature preserved means we still some way producing unambiguous parasequences. There however, rich record consider, compile compare, seven wetter intervals identified, breaks inferred drier, proxy drying. onset cessation does not align MIS: they occur greater frequency, but regular periodicity. Precession-paced insolation forcing often invoked key control on African climate, explain pacing all identified events. Overall, pattern complex corresponding space others opposing west-east trends. drying over 10 ka pronounced (Namib Desert), ephemerally wet south (southern Kalahari). patterns here provide framework scrutinised inspire refinements proposed Africa. Considering changes large geographic area highlights complexity responses continue test hypotheses about region.