CLIMATE RECORD EXTENDED BY 300,000 YEARS

A new ice core taken from a glacier in Vostok, Antarctica, has extended our view of climate back to 740,000 years ago, 320,000 years further than the longest previous ice core. The additional time reveals new and intriguing information about temperature shifts between glacial and interglacial periods, according to members of the European Project for Ice Coring in Antarctica (EPICA).

"In the last 400,000 years, you've got very cold, cold periods and very warm, warm periods," notes EPICA scientist Eric Wolff of the British Antarctic Survey. But in the time span between 400,000 and 720,000 years ago, the interglacial periods never were significantly warm, according to Wolff. Yet, in that same span, a higher proportion of time was spent in interglacial periods. Wolff said that further study would be necessary to determine what caused these variations. The information was published in the 10 June issue of Nature.

The EPICA scientists are next planning to examine the carbon dioxide (CO2) record, which they hope will provide clues to the relationship between CO2 and climate-specifically, whether or not CO2 levels are influenced by temperature changes. The researchers also hope that this core may eventually reveal data even farther back, to around 800,000 years ago. At the time of the Nature article, about 120 m of ice in the core remained to be drilled, and the scientists expect to continue their research on the core for another 2 to 3 years.

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ECHOES

"I suspect this isn't a record, but it's certainly up there."

-JAMES FRANKLIN, meteorologist with the National Hurricane Center in Miami, Florida, referring to the amount of time it took for Hurricane Charley to go from a category 3 to a category 4 rating. Charley, which hit the west coast of Florida, was a category 2 at 11:00 A.M. on 13 August. By 4:00 P.M. that day, it was a category 4. It went from category 3 to category 4 in approximately 1 h. Over the course of the day, its wind speed increased from 110 to 145 mph. A rapid hurricane intensification, also known as "bombing out," can lead to the kind of extraordinary destruction that Charley wrought, with 27 deaths and damages in the billions of dollars. Hurricane Andrew, the costliest natural disaster in U.S. history, had a similarly rapid growth, going from category 1 to category 5 in 30 h.