“Miracle” Microbes Thrive at Earth’s Extremes

Publication: National Geographic News   Date: September 17, 2004   View Article

For the past 30 years scientists have scoured the most inhospitable environments on Earth searching for life. Just about everywhere researchers look, they find it thriving in microscopic form.

These organisms, known as extremophiles, snuggle up to scalding hydrothermal vents in the Pacific Ocean. They cling to ice in Antarctica. They burrow in the high deserts of Chile and wallow in salty lake beds of East Africa.

Scientists Track Nutrients Around Oceans

Publication: National Geographic News   Date: June 17, 2004   View Article

The glass-hoarding behavior of single-celled plants called diatoms that dominate the surface layer of the ocean around Antarctica has allowed scientists to map the delivery of ocean nutrients around the world.

“Diatoms basically come to dominate wherever there is enough silicic acid and other nutrients around,” said Jorge Sarmiento, a professor of ocean and atmospheric sciences at Princeton University in New Jersey.

Polar Dinosaurs Spotlighted in “Dinosaurs of Darkness” Exhibition

Publication: National Geographic News   Date: March 29, 2004   View Article

If famed Norwegian explorer Roald Amundsen trekked across Antarctica a few hundred million years earlier, he may never have returned to reveal the details of the world’s underside. Cryolophosaurus ellioti might have eaten him for dinner.

The 22-foot-long (7-meter-long) carnivore with an unusual crest on its skull was one of several dinosaurs that thrived in the extreme polar regions of the world. Though the climate was warmer then than it is now, the dinosaurs endured months of darkness and temperatures that plunged below freezing.

Antarctic Eclipse: Fans Pay Big to Be Left in Dark

Publication: National Geographic News   Date: November 21, 2003   View Article

Penguin rookeries in Antarctica—weather permitting—will be audience to a total solar eclipse Sunday as the moon slips between Earth and the sun and casts a narrow band of the icy continent into daytime darkness.

A few hundred humans, too, hope to catch the celestial show. They’ve paid thousands of dollars to journey to—or over—Antarctica, the only landmass where the minutes-long event will be visible.

Antarctic Glaciers Surged After 1995 Ice Shelf Collapse

Publication: National Geographic News   Date: March 6, 2003   View Article

When a huge floating shelf of ice hinged to the northern end of the Antarctic Peninsula disintegrated in January 1995, several glaciers that were backed up into it surged towards the sea, according to a pair of Argentinean researchers.

The discovery marks the first positive evidence that glacial surge follows an ice shelf collapse. It may lead scientists to revive the previously discarded theory that ice shelves acts as dams that prevent inland glaciers from slipping into the seas.

Antarctic Desert Rich With Insights Into Life on the Edge

Publication: National Geographic News   Date: February 26, 2003   View Article

When British polar explorer Robert F. Scott discovered Antarctica’s Taylor Valley in 1903 he described it as a “valley of the dead.”

“We have seen no living thing, not even a moss or a lichen,” he wrote in The Voyage of the Discovery, his book about the journey.

Do Fish Use Cold Current To Cross Tropics

Publication: National Geographic News   Date: February 5, 2003   View Article

A big, old Patagonian toothfish found thousands of miles from home is bolstering the theory that large fish can take advantage of very deep, cold ocean waters to cross the tropics from one polar region to the other, swimming under warm water in which they ordinarily could not survive.

The Patagonian toothfish (Dissostichtus eleginoides) is normally found in the icy sub-Antarctic waters off South America. So when a commercial halibut fisherman pulled one in November 2000 from the Davis Straight off the coast of Greenland, he was surprised.

© 2008-2010 Collected Writings By John Roach