Ice cores and climate: looking back over a million years of earth history

Ice cores from Antarctica and Greenland have reshaped our understanding of how the climate system operates. We see in the cycles of temperature and carbon dioxide the pulse of the ice ages back to 800 thousand years. Ice core records for recent millennia show detailed changes that are linked to drivers of Australian climate such as the westerlies or El Niño from which we can infer past periods of drought. Australia has been a leading nation in ice coring, particularly in East Antarctica, with a focus on studies of climate over recent millennia and into the last ice age. Now, an international initiative is maturing to drill for a continuous record extending into the very oldest ice, more than a million years old. Australia has announced its plans to lead such an expedition, which will commence early next decade. This talk will look at why such an old ice core record matters, and how the project might proceed.
Dr Tas van Ommen is the leader of climate research with the Australian Antarctic Division. Tas has participated in six research expeditions to Antarctica, drilling ice cores and conducting airborne surveys of the ice and bedrock beneath. In his most recent trip he drove a tractor in a traverse across some 1300 km of the continent, crossing areas never previously visited. His research interests centre around high resolution ice core studies, connections with Australian climate and the stability and future of the Antarctic ice sheet. Tas is leading the Australian project to drill the ‘million year’ ice core and is also co-chair of the International Partnerships in Ice Core Sciences, an international planning body behind the search for this oldest ice core.