COSMOS MAGAZINE
Credit: Vera Davidova
Though a desert today, researchers have revealed ancient Arabia had lakes and rivers due to high rainfall.
Credit: Joshua Sortino
Geological evidence even points to a mass flooding event which carved out a 150km-long valley.
The ancient lake, formed around 9,000 years ago during a wet period known as “Green Arabia,” was fed by powerful African monsoons.
Credit: Communications Earth & Environment (2025). DOI: 10.1038/s43247-025-02224-1. https://www.nature.com/articles /s43247-025-02224-1
New findings show that a massive lake once existed where today there is only desert.
The lake was about 1,100km² (110,000 hectares) and 42m deep.
Lake Michigan and Lake Huron photographed from NASA’s Terra satellite. Credit: Wiki Commons.
Its area is about the same as Lake Michigan-Huron – the second largest lake in the world today after the Caspian Sea.
The formation of lake and riverine landscapes, together with grasslands and savanna conditions, would have led to the expansion of hunting and gathering groups and pastoral populations across what is now a dry and barren desert.
Michael Petraglia, Director of Griffith University’s Australian Research Centre for Human Evolution.
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As rainfall declined around 6,000 years ago, the landscape dried out, leading to the abandonment of once-thriving areas and the rise of nomadic lifestyles.
Morning Mist in the Rub al Khali Desert. Credit: Achim Thomae / Moment / Getty Images Plus.