A new study published in Communications Earth & Environment has shed light on long-term climate trends in Northeast Africa over the past few million years. The study, led by Assistant Professor Rachel Lupien, Department of Geoscience, Aarhus University, examined leaf wax isotopes from sapropels in sediment cores from the eastern Mediterranean Sea.

The study found a lot of variability of precipitation and vegetation even during just the wet phases of the monsoon. Low-frequency orbital cycles can explain up to half of these changes, but there is still a lot of unexplained variability. These additional fluctuations in climate and environment may be due to long-term changes in ice volume, tropical sea surface temperature, sea surface temperature gradients, or even lower-frequency orbital cycles.

This study is important because it provides new insights into the long-term climate history of Northeast Africa, and researchers believe that these long-term hydroclimate and environmental shifts may have played a role in hominin evolution and the dispersal of our early ancestors out of Africa.

You can read the paper here.