The Age of the Sahara desert

Related Articles

Related Articles

A team of scientists from Norway, France and China revise the view that the Sahara desert has existed for only the last 2-3million years.

The Sahara is the earth’s largest subtropical desert. During the last decades, multiple scientific studies have probed its geological and archaeological archives seeking to reveal its history. Despite some crucial breakthroughs, there are still basic questions that lack satisfactory answers.

An example being, how old is the Sahara desert? It is believed by many that the Sahara desert first appeared during the last 2 to 3 million years, however, recent discoveries such as ancient sand dunes and dust records in marine cores push the possible onset of Saharan aridity back in time by several million years. Until now, however, there have been no good explanations for such an early Sahara onset.

The study pinpoints the Tortonian stage (-7-11 million years ago) as an essential period for triggering North African aridity and creating the Sahara desert. Using snapshot simulations with the Norwegian Earth System Model (NorESM) model suite, the international team explored the climate evolution of North Africa through major tectonic shifts over the last 30 million years. They discovered that the region undergoes aridification with the shrinkage of the Tethys– a giant ocean that was the origin of the modern Mediterranean, Black and Caspian Seas– during the Tortonian.

Sahara desert via satellite: WikiPedia

The simulations are the first to show that the Tethys shrinkage has two main consequences for North African climate. First, it weakens the African summer monsoon circulations and dries out North Africa. Second, it enhances the sensitivity of the African summer monsoon and its associated rainfall to orbital forcing. The Totonian stage thus marks the time when North Africa shifted from permanently lush, vegetated landscape to a landscape experiencing arid/humid cycles on orbital timescales.

Subscribe to more articles like this by following our Google Discovery feed - Click the follow button on your desktop or the star button on mobile. Subscribe

Interestingly, these major alterations in North African climate and environment coincide with an important time period for the appearance of early hominids.

The study, led by Zhongshi Zhang from the Bjerkness Centre for Climate Research, Uni Research Climate, was published on Thursday September 18th in Nature. The research team comprises of Gilles Ramstein from Laboratoire des Sciences du Climat et de l’Environement; Mathieu Schuster from Institut de Physique du Globe de Strasbourg; Camille Li from the University of Bergen and the Bjerknes Centre for Climate Research; Camille Contoux from the Bjerkness Centre for Climate Research, Uni Research Climate; and Qing Yan from the Nansen-Zhu International Research Centre.



Contributing Source: Uni Research

Header Image Source: Wikimedia

- Advertisement -

Download the HeritageDaily mobile application on iOS and Android

More on this topic


Study Suggests the Mystery of The Lost Colony of Roanoke Solved

The Roanoke Colony refers to two colonisation attempts by Sir Walter Raleigh to establish a permanent English settlement in North America.

Drones Map High Plateaus Basin in Moroccan Atlas to Understand Human Evolution

Researchers from the Centro Nacional de Investigación sobre la Evolución Humana (CENIEH) have been using drones to create high-resolution aerial images and topographies to compile maps of the High Plateaus Basin in Moroccan Atlas.

The Kerguelen Oceanic Plateau Sheds Light on the Formation of Continents

How did the continents form? Although to a certain extent this remains an open question, the oceanic plateau of the Kerguelen Islands may well provide part of the answer, according to a French-Australian team led by the Géosciences Environnement Toulouse laboratory.

Ancient Societies Hold Lessons for Modern Cities

Today's modern cities, from Denver to Dubai, could learn a thing or two from the ancient Pueblo communities that once stretched across the southwestern United States. For starters, the more people live together, the better the living standards.

Volubilis – The Ancient Berber City

Volubilis is an archaeological site and ancient Berber city that many archaeologists believe was the capital of the Kingdom of Mauretania.

Pella – Birthplace of Alexander The Great

Pella is an archaeological site and the historical capital of the ancient kingdom of Macedon.

New Argentine fossils uncover history of celebrated conifer group

Newly unearthed, surprisingly well-preserved conifer fossils from Patagonia, Argentina, show that an endangered and celebrated group of tropical West Pacific trees has roots in the ancient supercontinent that once comprised Australia, Antarctica and South America, according to an international team of researchers.

High-tech CT reveals ancient evolutionary adaptation of extinct crocodylomorphs

The tree of life is rich in examples of species that changed from living in water to a land-based existence.

Fish fossils become buried treasure

Rare metals crucial to green industries turn out to have a surprising origin. Ancient global climate change and certain kinds of undersea geology drove fish populations to specific locations.

Archaeologists Discover Viking Toilet in Denmark

Archaeologists excavating a settlement on the Stevns Peninsula in Denmark suggests they have discovered a toilet from the Viking Age.

Popular stories