Nature paper on creation of the Sahara desert

Nature paper published today:

Aridification of the Sahara desert caused by Tethys Sea shrinkage during the Late Miocene


Summary:
Most evidence suggests that the modern Sahara desert first arose between two and three million years ago, coinciding with the initiation of major glaciations in the Northern Hemisphere. This study puts Saharan origins much earlier. Zhongshi Zhang et al. show that the shrinkage of the Tethys Sea — the progenitor of the modern Mediterranean, Black and Caspian seas — weakened the northern extension of the African monsoon and led to the creation of the Sahara desert about seven million years ago. Such a dramatic revision could lead to new investigations of the Sahara in fields as diverse as geology, evolutionary biology and climatology.

Read the paper here.