Ancient rainfall patterns during the 6,000-year "Green Sahara" period have been revealed: A team of researchers has compiled the first continuous record of the region's rainfall going 25,000 years into the past by analyzing marine sediments.

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Ancient rainfall patterns during the 6,000-year "Green Sahara" period have been revealed: A team of researchers has compiled the first continuous record of the region's rainfall going 25,000 years into the past by analyzing marine sediments.