Researchers have used sediment from the deep ocean bottom to reconstruct a record of ancient climate that dates back more than the last half-million years.
The record, trapped within the top 20 meters (65.6 feet) of a 400-meter (1,312-foot) sediment core drilled in 2005 in the North Atlantic Ocean by the Integrated Ocean Drilling Program, gives new information about the four glacial cycles that occurred during that period.
The new research was presented June 15 at the Chapman Conference on Abrupt Climate Change at Ohio State University's Byrd Polar Research Center. The meeting is jointly sponsored by the American Geophysical Union and the National Science Foundation.
Harunur Rashid, a post-doctoral fellow at the Byrd Center, explained that experts have been trying to capture a longer climate record for this part of the ocean for nearly a half-century. "We've now generated a climate record from this core that has a very high temporal resolution, one that is decipherable at increments of 100 to 300 years," he said. While climate records from ice cores can show resolutions with individual annual layers, ocean sediment cores are greatly compressed with resolutions sometimes no finer than millennia/ "What we have is unprecedented among marine records."
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