* Astronomy

Polar front shift and atmospheric CO2 during the glacial maximum of the Early Paleozoic Icehouse

An international team of scientists including Mark Williams and Jan Zalasiewicz of the Geology Department of the University of Leicester, and led by Dr. Thijs Vandenbroucke, formerly of Leicester and now at the University of Lille 1 (France), has reconstructed the Earth's climate belts of the late Ordovician Period, between 460 and 445 million years ago.
The findings have been published online in the Proceedings of the National Academy of Sciences of the USA - and show that these ancient climate belts were surprisingly like those of the present.

The researchers state: "The world of the ancient past had been thought by scientists to differ from ours in many respects, including having carbon dioxide levels much higher - over twenty times as high - than those of the present.  However, it is very hard to deduce carbon dioxide levels with any accuracy from such ancient rocks, and it was known that there was a paradox, for the late Ordovician was known to include a brief, intense glaciation - something difficult to envisage in a world with high levels of greenhouse gases."

University of Leicester