Driven by Earth’s Orbit, Climate Changes in Africa May Have Aided Human Migration

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In 1961, John Kutzbach, then a recent college graduate, was stationed in France as an aviation weather forecaster for the U.S. Air Force.

In 1961, John Kutzbach, then a recent college graduate, was stationed in France as an aviation weather forecaster for the U.S. Air Force. There, he found himself exploring the storied caves of Dordogne, including the prehistoric painted caves at Lascoux.

Thinking about the ancient people and animals who would have gathered in these caves for warmth and shelter, he took up an interest in glaciology. “It was interesting to me, as a weather person, that people would live so close to an ice sheet,” says Kutzbach, emeritus University of Wisconsin–Madison professor of atmospheric and oceanic sciences and the Nelson Institute for Environmental Studies.

Kutzbach went on to a career studying how changes in Earth’s movements through space – the shape of its orbit, its tilt on its axis, its wobble – and other factors, including ice cover and greenhouse gases, affect its climate. Many years after reveling at Ice Age cave art, today he’s trying to better understand how changes in Earth’s climate may have influenced human migration out of Africa.

Read more at University of Wisconsin-Madison

Image: An aerial view of northern Africa, the Arabian Peninsula and the Mediterranean Basin. A new study led by University of Wisconsin–Madison’s John Kutzbach shows that changes in Earth’s orbit, greenhouse gases, and ice sheets influenced the planet’s climate over the last 140,000 years and may have provided wetter, greener corridors at times that permitted human migration out of Africa and into the Middle East. IMAGE COURTESY OF GOOGLE EARTH