In this video excerpt from NOVA: "Extreme Ice," learn about the historical record of climate changes captured in ice. Scientist Jim White discusses how ice cores store information about global climate and how scientists can study them. Graphs constructed from ice-core data illustrate the correlation between increases in greenhouse gases (such as carbon dioxide) and rises in global temperatures and sea levels. In the past, a major warming event caused a portion of Greenland's ice sheet to melt and raise sea levels. The recent ice-core record shows that as a result of the burning of fossil fuels, current levels of greenhouse gases are the highest they have been in the last half-million years, potentially putting Greenland's ice sheet in danger of melting more quickly than before.
This video is available in both English and Spanish audio, along with corresponding closed captions.
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