Rambler's Top100





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the climate of Atlanta to Boston in a few decades, followed a few thou-
sand years later by an equally rapid return to normal. These sudden shifts in
climate, accompanied by out-of-place rocks being dumped into the North
Atlantic, were called "Heinrich events" after the German scientist who first
discovered them.
Doug's idea was that you could understand both the origin of the rocks
in the ocean bottom cores and the dramatic shift in the weather in terms
of the behavior of the ice sheet that covered North America over much of
the past 80,000 years. The depth of the sheet would increase as snow fell
and compressed into ice, but when the ice lying on top of Hudson Bay
reached to a height of about 10,000 feet, the soft rocks underneath would
crumble and mix with melt water, forming a slippery paste, and the whole
thing would slough down Hudson Strait and eventually into the ocean,
sending out an armada of icebergs, each with a load of crushed rocks fro-
zen into its undersides. When the icebergs melted, the rocks were
dumped. At the same time, the additional fresh water changed the patterns
of ocean currents while the absence of two vertical miles of ice changed wind
patterns.
Text 5
Elephant seals, the champion divers of the deep
By Kathleen McAuliffe
These ponderous pinnipeds continually set new records for diving to
crushing depths; researchers are hard at work to discover just how they do it.
The California bathers do not welcome a truck on the beach overlooking
Monterey Bay. Annoyance quickly gives way to curiosity, however, when a
coffin-shaped cage becomes the center of activity. As parents and children
gather round for a closer view, marine biologist Burney Le Boeuf signals
a team of six to unload the crate at the water's edge. Out rolls Camille, a
juvenile northern elephant seal with a video camera attached to her
back. Big brown eyes blinking in the noonday sun, she circles once,
snarls at her human abductors and then galumphs toward the ocean.
Moments later, the world's first video-shooting elephant seal disappears un-
der a big wave.
Le Boeuf, a professor at the nearby University of California at Santa
Cruz, is gambling that the animal's homing instincts will guide it back to a
beach on the mainland behind the island of Ano Nuevo, a popular spring
gathering ground of elephant seals 18 miles up the coast. "You never
know the film might just reveal something we didn't expect" he enthuses.
A moment later, his jubilant spirit falls prey to realism. "Or it might just
be all murk."