Jakarta –
Dunes and rocky plateaus in Sahara desert very old, but it seems that this is not entirely true. Maybe humanity will still see a period of greening of the Sahara Desert.
Of course this is not a sign of the end of the world. A new study shows that this vast region of North Africa will change from arid desert to lush green forest every 21 thousand years or so. The last period the Sahara became a green forest occurred between 15 thousand and 5 thousand years ago.
The research confirms that this is not just a strange change, but rather part of a cyclical transformation that changes the region from dry to humid approximately every 21 thousand years.
“The cyclical transformation of the Sahara Desert into a savanna and forest ecosystem is one of the most extraordinary environmental changes on the planet,” said Dr Edward Armstrong, lead author of the study and a climate scientist at Helsinki University Bristol University as quoted from IFL Science.
“Our study is one of the first climate modeling studies to simulate the African Humid Period with magnitudes comparable to what paleoclimate observations indicate, thereby revealing why and when this event occurred,” it said.
This research aims to better understand the so-called ‘North African Humid Period’ over the last 800 thousand years using a recently developed climate model.
Their study confirms the idea that periodic wet phases in the Sahara are driven by changes in the Earth’s orbit around the Sun. It is generally agreed that the ‘greening’ of the Sahara is caused by the Earth’s wobble on its axis, which impacts the seasons and determines the amount of energy received by this part of the planet. This ultimately influences the strength of the African Monsoon, which helps control how much vegetation is spread across this vast region.
But their workings also suggest that these cycles may be influenced by ice sheets at high latitudes far away in the Northern Hemisphere. Their research notes that moist periods did not occur during the Ice Age when most of Earth’s high latitude regions were covered in thick layers of glacial ice.
They speculate that this layer of ice helps cool the atmosphere like a refrigerator, limiting the African Monsoon system and suppressing plant growth in the Sahara Desert.
The cycle of transformation in North Africa not only had a major impact on the Sahara, but also had a major impact on our history. However, some of humanity’s greatest early achievements, namely migration out of Africa, were largely determined by the conditions of the Sahara.
“The Sahara region is a kind of gateway that controls the spread of species between North and Sub-Saharan Africa, as well as in and out of the continent,” explains Miikka Tallavaara, co-author and Assistant Professor of Hominin Environments at Helsinki University.
“The gate opened when the Sahara was still green and closed when the deserts began to emerge. This alternation of moist and dry phases has had major consequences for the distribution and evolution of species in Africa. Our ability to model the humid period in North Africa is a major achievement and means we are now also better able to modeling human distribution and understanding the evolution of our genus in Africa,” Tallavaara concluded.
Watch the video “3 signs of the end of the world in Israel that shocked the world”
(rns/agt)
2023-09-21 22:45:09
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