What anomaly created the Sahara Desert.?

Question

I've often seen this posted by the proponents of GW.

Answer 1

Check this link:

http://en.wikipedia.org/wiki/Sahara_Dese...

Answer 2

A theory is that when India slammed into Asia, it pushed the Himalayan Mountain range further up and rerouted the winds.  There was more warm wind being dumped into Northern Africa and the cooler air was redirected into Northern Asia/Europe.  The area now known as the Sahara slowly began to form after this event but was impeded by many glacial periods.  (I remember seeing this on The Science Channel, but can't remember who the scientist(s) are that theorized this).

There is also a theory that a change in the Earth's axis created the Sahara.  The shift in the axis caused more radiation to be sent towards the Sahara area.

  "Some 9,000 years ago the tilt of the Earth's axis was 24.14 degrees; today it is 23.45 degrees. Today, the Earth is closest to the Sun in January. Nine thousand years ago, our planet was closest to the Sun at the end of July."

http://news.bbc.co.uk/1/hi/sci/tech/3900...

Answer 3

People ,and climatic changes

Sahara's Abrupt Desertification Started By Changes In Earth's Orbit, Accelerated By Atmospheric And Vegetation Feedbacks

http://www.sciencedaily.com/releases/199...

it was green once

http://www.newscientist.com/channel/bein...

One of the driest deserts in the world, the Saharan Tenere Desert, hosted at least two flourishing lakeside populations during the Stone Age, a discovery of the largest graveyard from the era reveals.It had been used as a burial site by two very different populations during the millennia when the Sahara was lush.

hunter-gatherers who grew up to two metres tall called Kiffian,All traces of the Kiffian vanish abruptly around 8,000 years ago, when the Sahara became very dry for a thousand years

they were replaced by the Tenerians, who were of a shorter and more gracile build, based themselves at this site. Bones and artifacts dated to the Tenerian episode suggest that these people herded cattle and hunted fish and wildlife

over grazing and farming followed and the Sahara was born ,

You cannot deforest or over graze on the equator

to return growth under this hot sun is normally impossible .

it can be done at great expense with shade netting

but normally any new growth just burns up.