[muawiyah]

The Earth's angle of inclination changed about 2 degrees. That cooled down the Sahara with the result that the monsoons no longer came in and watered the place.

German researchers have proposed that if we could heat up the Sahara by propagating hardy broadleafed plant species, we might well be able to pull the monsoons back in and create a new pluvial period.

It wasn't insolation that changed, but rather the capacity of the environment to absorb and keep heat.

(Yes, plant cover makes an area warmer because it will trap water vapor, a powerful greenhouse gas. Gee, maybe apparant global warming has to do with expanded irrigation. Whadda' ya' think, eh?!)

[Lokibob]

Since "broadleafed plant species" is a bush, you are saying that it IS BUSH'S fault!!!!

[blam]

"German researchers have proposed that if we could heat up the Sahara by propagating hardy broadleafed plant species, we might well be able to pull the monsoons back in and create a new pluvial period."

I don't think that is to far fetched.