1. Pleistocene Pluvial Lakes in East Africa Morgan Monz

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

3. Location Victoria Tanganyika Malawi (http://www.biomedcentral.com/c ontent/figures/1471-2148-5-17-1- l.jpg)

4. Modern Day Climates Arid to semi arid Climate trend Ratio of precipitation to potential evaporation (PET) (http://www.grida.no/images/series/vg- africa/graphics/25-aridity.jpg)

5. Hydrologic cycle Hadley Cells Intertropical Convergence Zone (ITCZ) Bimodal distribution (http://upload.wikimedia.org/wikipedia/commons/d/d7/ITCZ_january-july.png)http://upload.wikimedia.org/wikipedia/commons/d/d7/ITCZ_january-july.png

6. Evidence for Pluvial Lakes Geomorphologic Geochemical Archeological (http://farm3.staticflickr.com/2557/5774714465_db908f9385_z.jpg)

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

8. Glaciation in Pleistocene Abrupt Termination of LGM Milankovitch cycles Increased insolation http://user.gs.rmit.edu.au/caa/global/graphics/insolation.jpg

9. Lake Victoria Shallow basin between branches of rift valley Levels of total organic carbon and hydrogen content Paleosol records Seismic profiles (http://www.eoearth.org/files/119601_119700/119602/400px-Lake_victoria_basin.jpg)

10. Lake Tanganyika Occupies several rift basins within the Western Rift Valley Two intervals of dramatic drop during late pleistocene Pollen records (http://www.ncdc.noaa.gov/paleo/pubs/tierney2008/tanganyika.jpg)

11. Lake Malawi Rift Basin along the East African Rift Diatom assemblages About a 100 m drop in lake levels with the Last Glacial Maximum (http://www.eosnap.com/public/media/2011/11/malawi/20111108-malawi-thumb.jpg)

12. 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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