for National Geographic News
The energy source of the future may lie beneath the ocean floor and under Arctic permafrost, scientists say.
Both places are sources of gas hydrates, strange icelike substances that trap methane—the primary component of natural gas.
"It's not frozen gas," explained Timothy Collett of the U.S. Geological Survey in Denver. "It's [formed] from the interaction of gas and water."
The hydrates were discovered in 1983, and no one knows how many of them exist.
But there appear to be enough hydrates to represent a larger energy source than all of the word's gas, oil, and coal combined, Collett said at a meeting of the American Physical Society in Denver, Colorado, on March 5.
Twenty-three percent of the Earth's surface is covered by permafrost and may have hydrates beneath it, he said, and most of the world's oceans are deep enough for hydrates to exist just under the seabed.
Most deep-sea hydrates are likely to be found near the margins of continents, he added.
Because each cubic foot (0.02 cubic meter) of hydrate releases 160 cubic feet (4.5 cubic meters) of natural gas, "they're a very good storage system for methane," Collett said.
Hydrates are being studied as a fuel source not only in the U.S., which is looking for an alternative to foreign oil, but in India and China, whose burgeoning economies need a new energy source.
Japan and Korea are also interested, Collett said.
(See National Geographic magazine's "The End of Cheap Oil".)
Focus on Arctic
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