Pleistocene Pluvial Lakes in East Africa Morgan Monz

Outline Locations Modern climates Evidence for pluvial Lakes Pleistocene glaciation Specific pluvial lakes

Location Victoria Tanganyika Malawi ( ontent/figures/ l.jpg)

Modern Day Climates Arid to semi arid Climate trend Ratio of precipitation to potential evaporation (PET) ( africa/graphics/25-aridity.jpg)

Hydrologic cycle Hadley Cells Intertropical Convergence Zone (ITCZ) Bimodal distribution (

Evidence for Pluvial Lakes Geomorphologic Geochemical Archeological (

Glaciation in Pleistocene Three major periods 30% of Earth’s surface was glaciated periodically Cooler climates lead to less evaporation and less precipitation

Glaciation in Pleistocene Abrupt Termination of LGM Milankovitch cycles Increased insolation

Lake Victoria Shallow basin between branches of rift valley Levels of total organic carbon and hydrogen content Paleosol records Seismic profiles (

Lake Tanganyika Occupies several rift basins within the Western Rift Valley Two intervals of dramatic drop during late pleistocene Pollen records (

Lake Malawi Rift Basin along the East African Rift Diatom assemblages About a 100 m drop in lake levels with the Last Glacial Maximum (

Summary East Africa has experienced a variety of climatic conditions Large scale glaciation can be correlated to pluvial periods Evidence for multiple dramatic lake level fluctuations in East Africa

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