http://news.yahoo.com/ancient-climat...141010126.html
Inside the National Ice Core Laboratory in Denver rests more than 11 miles (18 kilometers) of ice, drilled from Earth's glaciers, which are shedding new light on the dimly understood history of the planet's climate.
These ice cores, taken from both Antarctica and the Arctic, provide a unique glimpse into the past. Scientists take pieces of the ice to perform a wide variety of experiments.
Some scientists study the bubbles trapped within the cores — each a tiny pocket of air enclosed at the time the ice formed, essentially frozen in time. Testing that air for various chemicals can tell scientists a lot about what the Earth's climate was like at the time the bubble formed.
Other researchers look at levels of chemicals that can reveal how much precipitation fell in any given year. The samples also contain particles of volcanic dust that speak to Earth's geologic past and its potential influence on climate....
U.S. Geological Survey scientist Joan Fitzpatrick is looking at samples from the West Antarctic Ice Sheet to research how these masses of frozen water respond to changing climate. To do that, she creates thin wafers of ice from the core and then places the wafer samples under a microscope to analyze individual ice crystals.
"If the climate is warming, is the ice sheet going to get thinner overall?" she asked in a statement. "We really don't have a good handle on how the ice sheet as a whole will respond in a changing climate." But the samples at the lab allow scientists to compare recent data with more long-term information, to discover the impact of our behaviors on the climate.