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Touching Climate History
Photograph by Peter Essick

The gloved hand of Tracy Mashiotta, a researcher at Ohio State's Byrd Polar Research Center, points to a dust band in an ice core from Peru's Quelccaya ice cap. The dust is swept up from Peru's high desert and deposited on the glacier each year during the dry season, creating the glacial equivalent of a tree's growth ring. Scientists use such data along with oxygen isotope ratios to extrapolate temperature and precipitation for each year. Such cores from Quelccaya have produced the longest annual climate record ever recovered from the tropics, dating back 2,200 years.

Photo Fast Facts

Camera: Canon EOS 1V
Film Type: Fujichrome Provia 100
Lens: 24-70mm
Speed and F-Stop: 1/50 @ f/11
Weather Conditions: Indoors
Time of Day: Unrecorded
Lighting Techniques: Tungsten and available light


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