A paper has been published in Quaternary International about
Extreme Nile floods and famines in Medieval Egypt. It is:

Fekri A. Hassan, F. A., 2007, Extreme Nile floods and famines
in Medieval Egypt (AD 930–1500) and their climatic implications.
Quaternary International. vol. 173–174, pp. 101–112
doi:10.1016/j.quaint.2007.06.001 [www.sciencedirect.com]

The abstract concludes:

“The transition from one state to the other was characterized
by incidents of low, high or a succession of both low and high
extreme floods. The cluster of extreme floods was detrimental
causing famines and economic disasters that are unmatched
over the last 2000 years.”

Yours,

Paul H.

"The past is never dead. It's not even past."
William Faulkner, Act 1, Scene III, Requiem for a Nun (1951)