Around 10,500 to 5,500 years ago, before Egyptian Pharaonic Era, Sahara Desert, the largest and hottest desert on Earth was habitable. There was rains, and even monsoon season. Ancient human settled all around today's one of the driest places. Vegetation can be grown. Animals were fed for livestock, especially domestic ones such as sheep and goats. This is not only a scientific calculation, but the hard evidences, found by the researchers, include 500 new radiocarbon dates of human and animal remains from more than 150 excavation sites.
Then, What Changed Green Sahara into A Desert?
Human activities? Definitely not! 5,500 years ago was very long before our Industrial Revolution. That is why scientists have been discussed, and it resulted in many possible causes. The most agreed one is a change in the Earth's tilt. It may sound odd, but the axial tilt changes bit by bit everyday - about 26 mm a year. During 41,000 years, it changes in cycle between 22.1 - 24.5 degree, from the angle of today's 23.5. Changes for thousands of years eventually made climate dramatically changed in Sahara. Rains decreased, and finally suspended some 5,000 years ago, prompting humans to move to remaining habitable niches in the Nile Valley, and began the Pharaonic Era.
We can learn from this as the undefeatable power of mother Earth, but when we know, and now we have technology, we just need our helps to be concerned about the climate changes, so we can fix and prevent it from happening.
ACTs Of Green
ONE SMALL CHANGE
ONE BIG DIFFERENCE
Credit (Story & image)