title: Isotopic evidence for dramatic climatic changes in East Africa during the Pleistocene.
abstract: Rainfall decreased dramatically in the Lake Turkana region 1.8-2.0 Myr ago and in the Olduvai Gorge region 0.5-0.6 Myr ago. This is documented by a major increase in the delta18O values of pedogenic and groundwater carbonates at these times. The data suggest that meteoric water of the earlier, more humid climate was 2-4 per mil lower in 18O content than modern waters of these regions.
authors.affiliation: Department of Geology and Geophysics, University of California, Berkeley, CA 94720, USA.
authors.forename: T E
authors.initials: TE
authors.lastname: Cerling
authors.forename: R L
authors.initials: RL
authors.lastname: Hay
authors.forename: J R
authors.initials: JR
authors.lastname: O'Neil
mesh_terms: D002254:Carbonates / Q000032:analysis* / Q000737:chemistry*; D002980:Climate; D005618:Fresh Water / Q000737:chemistry*; D019015:Geologic Sediments / Q000737:chemistry*; D049690:History, Ancient; D006859:Hydrogen / Q000032:analysis / Q000737:chemistry; D007630:Kenya; D010103:Oxygen Isotopes; D011891:Rain; D013636:Tanzania; D013997:Time Factors
chemical_list: D002254:Carbonates; D010103:Oxygen Isotopes; D006859:Hydrogen