Ed Brook, of Oregon State University, said that ice is a great medium for trapping air, as it does so without altering it much, Stuff.co.nz reported.
The ice in the North and South poles were formed from thousands of years of snowfall that never melted.
Over time, the weight of the snow compacted the individual snowflakes, till they eventually formed ice.
The study has been published in the journal Climate of the Past.
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