Scientist says ice cores point to climate change - The Daily Utah Chronicle - News

For more than 30 years, Lonnie Thompson, a scientist from the Byrd Polar Research Center in Ohio, has led 57 field expeditions, published more than 200 articles and visited 16 countries—all for the cause of recording climate change.

Melting glaciers suggest there will be a harsh change of climate in the coming years, according to his research.
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"They are used in many ways—most importantly, ice contains air bubbles that record the composition of the atmosphere at the time the bubbles were trapped, so using this we can measure the amount of important greenhouse gases from almost a million years ago," said David Chapman, professor of geophysics.