6,000 years ago the Sahara Desert was tropical, so what happened?

[rangerrebew]

6,000 years ago the Sahara Desert was tropical, so what happened?

Date:
    November 30, 2016
Source:
    Texas A&M University
Summary:
    As little as 6,000 years ago, the vast Sahara Desert was covered in grassland that received plenty of rainfall, but shifts in the world's weather patterns abruptly transformed the vegetated region into some of the driest land on Earth. Now a researcher is trying to uncover the clues responsible for this enormous climate transformation -- and the findings could lead to better rainfall predictions worldwide.

https://www.sciencedaily.com/releases/2016/11/161130141053.htm

[rangerrebew]

Anyone with half a brain knows its was caused either by anthropogenic global warming or cow farts!

[Free Vulcan]

And it's that sand and dust that creates the jungle climate of the Amazon on the other side of the world. 6K years ago that area was also more like grassland.

[verga]

Anyone with half a brain knows its was caused either by anthropogenic global warming or cow farts!

No way, it was due to the government being put in charge of rainforest growth. 

[rangerrebew]

No way, it was due to the government being put in charge of rainforest growth.

I stand corrected.  I was venting against people like St. Algore.