Around five and half millenia ago, northern Africa went through a dramatic transformation. The Sahara desert expanded and grasslands, forests and lake

Dramatic Shift in Africa 5,000 Years Ago Could Be a Warning of The Future

submited by

Style Pass

2024-05-12 16:00:10

Around five and half millenia ago, northern Africa went through a dramatic transformation. The Sahara desert expanded and grasslands, forests and lakes favoured by humans disappeared. Humans were forced to retreat to the mountains, the oases, and the Nile valley and delta.

As a relatively large and dispersed population was squeezed into smaller and more fertile areas, it needed to innovate new ways to produce food and organise society. Soon after, one of the world's first great civilisations emerged – ancient Egypt.

This transition from the most recent "African humid period", which lasted from 15,000 to 5,500 years ago, to the current dry conditions in northern Africa is the clearest example of a climate tipping point in recent geological history. Climate tipping points are thresholds that, once crossed, result in dramatic climate change to a new stable climate.

Our new study published in Nature Communications reveals that before northern Africa dried out, its climate "flickered" between two stable climatic states before tipping permanently. This is the first time it's been shown such flickering happened in Earth's past. And it suggests that places with highly variable cycles of changing climate today may in some cases by headed for tipping points of their own.