Australian work on the analysis of an ice core, taken from the icecap at Law Dome near Casey Station, is confirming data from other Antarctic ice analyses and assisting us in drawing an accurate picture of the history of Antarctic climate. The Australian core is particularly significant because it comes from a region with high precipitation, allowing a high resolution of the climate over the past 80,000 years. So good is the record that chemical markers from the air trapped in the ice allow us to pinpoint ancient volcanic eruptions, and trace the history of the world's biological productivity. There is no doubt that climate is changing. An international study, Regional Sensitivity to Climate Change, has recently been established, with Australian scientists taking a leading role.
Climate change has measurable consequences.
Changes in the distribution of plant species and their microhabitats can be used to make predictions about the future, and changes in the rates at which genetic mutations occur gives us a clue about how climate change is a factor in evolution. Warming of the earth's surface and its lower atmosphere leads to cooling in the upper atmosphere. The ozone hole over the Antarctic is now a closely monitored international signal of global health but we do not know enough about the climatology of the middle and upper atmosphere. Cooling rates of 0.7 C per year have been reported from northern hemisphere measurements. It has also been observed that noctilucent or 'night shining' ice-clouds that form at an altitude of around 83 km, mainly in summer in polar regions, are increasing in occurrence and extent.