sahara thousands years ago
Post on 02-Dec-2014
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WHAT DID THE SAHARA LOOK LIKE SIX TO TEN THOUSAND YEARS AGO ?
Wendy Bintner
Sahara Irrigation Mega-Engineering Project
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SAHARA TODAY
Description of Sahara Today
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Sahara : sand, sun, scorcher temperatures
GREEN SAHARA
What ? Wet and rainy conditions in the northern Africa
When ? 9 000 and 6 000 years ago How ? Climate change
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Green Sahara
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GREEN SAHARA
Water
• Rivers• Lakes
Life
• Fertile conditions • Animals
Humans
• Humans
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GREEN SAHARA
Crocodiles, elephants, giraffe, hippos, antelopes, fish, …
Civilization used rivers : boat, raft, fishing (hook, harpoon, line, …)
Civilization learned a lot : cooking (porridge, soup, …), pottery,
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HOW DO WE KNOW ?
Sediment : evidence of water Cave painting : evidence of civilization and
animals
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How Earth Made Us - Sahara
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WHAT’S HAPPENED
After 2 thousands years, the drier conditions that prevailed prior to the Green Sahara returned. Desertification advanced, and the Sahara desert formed (or re-formed). Arid conditions have continued through to the present day.
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A NEW GREEN SAHARA SOON ?
Computer model simulations : an expansion of the vegetation cover in the Sahara Desert ( human-driven climate change leads to aggressive global warming)
Sahara won’t actually become greener than it is today, as the simulations do not account for the influence of human activity in this area.
8Science Daily
Thanks for listening.
Do you have any questions ?
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wendy.bintner(at)etu.emse.fr
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