What made sahara go from a green savana to the desert we know today !

1. THE
SAHARA
6000YEARS AGO !

2. The SaharaToday

3. Desert Zones In theWorld
The largest deserts
are located in the
dry areas of our
planet !

4. SaharaTIMELINE
• 22,000 to 10,500 years ago:The Sahara
extended 250 miles further south than it does today.
• 10,500 to 9,000 years ago: Monsoon rains begin sweeping into the Sahara,
transforming the region into a habitable area swiftly settled by NileValley dwellers.
• 9,000 to 7,300 years ago: Continued rains, vegetation growth, and animal migrations
lead to well established human settlements, including the introduction of domesticated
livestock such as sheep and goats.
• 7,300 to 5,500 years ago: Retreating monsoonal rains initiate desiccation in the
Egyptian Sahara, prompting humans to move to remaining habitable niches in
Sudanese Sahara.The end of the rains and return of desert conditions throughout the
Sahara after 5,500 coincides with population return to the NileValley and the beginning
of pharaonic society.

5. Why ?
• Earth´s Orbital TILT!

6. Earth its a system
• Everything we do to alter the natural equilibrium of our planet will have
unexpected side effects, this is why its very important to study and
understand in dept the way our planet WORKS, if not we will not have a
place to live in!

7. References
• http://pre15.deviantart.net/a508/th/pre/i/2012/231/f/4/green_sahara_concept_by_darkriku90-d5bo8fc.jpg
• https://en.wikipedia.org/wiki/File:Tassili_-_whites_and_blacks_leaving_in_harmony%3F.jpg
• https://upload.wikimedia.org/wikipedia/commons/a/a7/Sahara_satellite_hires.jpg
• http://www.huffingtonpost.co.uk/entry/sahara-desert-tropical-rainforest_uk_58400b97e4b0bd623ad9dce7
• https://www.quora.com/Why-are-most-deserts-located-away-from-the-equator
• http://montessorimuddle.org/2011/04/21/global-atmospheric-circulation-and-biomes/
• http://www.wallpaperup.com/438038/sand_clock_time_sky_wood.html
• http://agron-www.agron.iastate.edu/courses/Agron541/classes/541/lesson07b/7b.1.html
• http://www.fatemag.com/the-truth-about-pole-shifts/
• http://www.livescience.com/4180-sahara-desert-lush-populated.html