Slashdot Mirror
The Millennia After Tomorrow?
frankthechicken writes "Analysis of a three-kilometer-long ice core drilled from the Antarctic, has revealed our planet has had eight ice ages during that period, punctuated by rather brief warm spells - one of which we enjoy today. And fortunately, the end of the world is not the day after tomorrow, instead it may be expected on Sunday, 17000."
rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rrtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa tfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa rtfa
Analysis of a three-kilometer-long ice core drilled from the Antarctic, has revealed our planet has had eight ice ages during that period,
Sorry, not being familiar with the geological ebbs and flows of the polar ice caps, might someone explain how long in time 3 Kilometers worth of ice is?
And, on a side note, might this information also lend credence to the idea that the current warming trend is a natural phenomena? One that we couldn't stop if we tried and one that we may have insignifanctly affected if at all? Just curious.
"Are you ready to go into the freezer?" It's a warm summer's day in Le Fontanil, southeastern France, but glaciologist Jerome Chappellaz is pulling on a hefty parka and snow boots. He punches a button and a door slides open into a vast commercial cold store, where whirring fans add a bitter wind-chill to the temperature of -25 C. Although we have come to look at ice, we're first confronted with three floors of wooden pallets stacked up to the ceiling, bearing sides of beef, rings of yellow goat's cheese and boxes of frozen raspberries.
"We work with a raw material that is very close to melting, so we're always close to losing our samples," says Chappellaz, from France's leading glaciology laboratory - the Laboratoire de Glaciologie et Géophysique de l'Environnement (LGGE) in Grenoble, 15 kilometres from Le Fontanil. "But they have millions of euros of food in here, so there's no way they will let it thaw."
That's just as well, because the samples Chappellaz is talking about are far more precious than cheese. Tucked away in the attic, in scores of cardboard cartons cross-wrapped with black straps like slightly battered Christmas presents, is one of the world's most extraordinary archives - a record of ancient climate written into 15 kilometres of ice cores, taken from mountain glaciers and the frozen caps of Greenland and Antarctica. Chappellaz rummages in a carton, and lifts out a long thin wedge of ice, whose curved side is scored with spiral rings from each turn of the drill bit. Although it looks unremarkable, this core is setting the climate world buzzing. It comes from so deep in the Antarctic ice sheet that any bubbles have had the breath squashed out of them, and the ice is as clear as glass. Dating from roughly 740,000 years ago, it is also the oldest ice core ever retrieved.
The ice was drilled at Dome C in the East Antarctic ice sheet by a consortium called the European Project for Ice Coring in Antarctica (EPICA). It has nearly doubled the age record for an ice core - previously set by a core drilled 500 kilometres from Dome C, at the Russian station Vostok a decade ago. The flagship for ice-core research, the Vostok core extends back around 400,000 years, and contains four ice ages1. It was a resounding success for researchers, demonstrating - among other things - that carbon dioxide levels in the atmosphere have marched in exact step with temperature for hundreds of thousands of years2.
Cold comfort
But, frustratingly, the Vostok core stopped in the middle of a period known as stage 11, which occurred about 425,000-395,000 years ago, and which the EPICA core has now fully embraced. Researchers are particularly keen to explore this period because it is the last time that the Earth's orbit was very nearly identical to its present one, making it a potential model for our own climatic future. With its record of atmospheric gases frozen into the ice, the EPICA core could also reveal secrets of a mysterious climate transition that started a million years ago.
The site at Dome C, chosen for its exceptionally thick ice, i