"At approximately 2200 BC, occupations of Tell Leilan and Tell Brak (in northern Mesopotamia) were suddenly abandoned...a marked increase in aridity and wind circulation, subsequent to a volcanic eruption, induced considerable degradation in land use conditions…this abrupt climatic change caused abandonment of Tell Leilan, regional desertion, and collapse of the Akkadian empire based in southern Mesopotamia.

Synchronous collapse in adjacent regions suggests the impact of abrupt climatic change was excessive."

(This is according to a statement made in 1993 by Harvey Weiss, professor of Near Eastern archaeology at Yale University).

The site of Tell Leilan was abandoned soon after the city's massive walls were constructed, its temple rebuilt and its grain production reorganized.

The debris, dust, and sand that followed show no trace of human activity.

Soil samples show fine wind-blown sand, no trace of earthworm activity, reduced rainfall and indications of a drier and windier climate.

Evidence shows that skeleton-thin sheep and cattle died of drought, and up to twenty-eight thousand people abandoned the site, seeking wetter areas elsewhere.