Ancient Egypt was destroyed by drought, discover Scottish experts

But the fall of the great Egyptian Old Kingdom may have been helped along by a common problem which remains with us now - drought.

Researchers from the University of St Andrews have confirmed that a severe period of drought around 4,200 years ago may have contributed to the demise of the civilisation.

Using seismic investigations with sound waves, along with carbon dating of a 100-metre section of sediment from the bed of Lake Tana in Ethiopia, the team were able to look back many thousands of years. They were able to see how water levels in the lake had varied over the past 17,000 years, with the sediment signalling lush periods but also times of drought.

Lake Tana - the source of the Blue Nile river - flows to the White Nile at Khartoum and eventually to the Nile Delta.

Dr Richard Bates, senior lecturer in earth sciences at St Andrews, said their studies had confirmed that the ancient civilisation that was the Egyptian Old Kingdom - often referred to as the Age of the Pyramids - may have experienced a prolonged period of drought of the same severity being seen in parts of Africa now.

"Part of this research was driven by whether we could see anything in the lake sediment that would help us understand more about that period of drought, which was during the 90-year period at the end of the Old Kingdom, which really caused its demise," he said.

"There were great riots, and anarchy breaking out as a result of it."

Historical records have suggested the region was hit by a drought spanning several decades, forcing people to extreme measures with some writings even suggesting people were forced to eat their own children.

This drought has now been confirmed by information collected by the St Andrews team, along with colleagues from the University of Aberystwyth.

Dr Bates said: "It was coming to the end of a particularly long period in the pharaohs and there is quite a good record that law and order was breaking down.

"Most of that comes as a result of pressures outside and in this case it was the failing agricultural system where that was such a dominant part of society, and the result of that being anarchy."

But Dr Bates said they had found evidence of much more severe droughts up to 19,000 years ago in Africa.

"Those were way more severe than either the ones we have got today or this time period 4,200 years ago," he said.

"That was significant, but actually within the last 100,000 years it was by no means the worst.

"That's interesting … we are getting droughts in different places that are causing severe conditions, but these are compared to the absolute worst ones that could and have happened, and by the law of succession will happen again."

Dr Bates said they hoped the work would improve understanding of climate change.