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- <text id=93TT2119>
- <title>
- Aug. 30, 1993: Mystery of the 300-Year Drought
- </title>
- <history>
- TIME--The Weekly Newsmagazine--1993
- Aug. 30, 1993 Dave Letterman
- </history>
- <article>
- <source>Time Magazine</source>
- <hdr>
- SCIENCE, Page 46
- Mystery of the 300-Year Drought
- </hdr>
- <body>
- <p>The world's first empire may have been doomed by a volcano and
- an epic dry spell
- </p>
- <p>By CHRISTINE GORMAN
- </p>
- <p> Before the Han dynasty, before Alexander the Great, even before
- Ramses, the first empire the world ever knew was built by a
- Mesopotamian ruler named Sargon of Akkad. He conquered and subjugated
- dozens of cities and villages between the Tigris and Euphrates
- rivers more than 4,000 years ago, forcing them to pay tribute
- in wheat, barley and silver. For a century the regime flourished,
- first under Sargon and then under his grandson until suddenly,
- mysteriously, it collapsed. Neither the capital city of Akkad,
- famed for its harbor filled with vessels from distant shores,
- nor the imperial records, etched in cuneiform and possibly chronicling
- the empire's demise, have ever been found.
- </p>
- <p> Now the mystery may have been solved by researchers from the
- U.S. and France. In last week's Science, they put forth evidence
- that the empire was undone by a combination of climatic catastrophes.
- First a volcanic eruption blanketed the region in ash. Then
- a drought, which eventually lasted 300 years, crippled the farming
- communities on which the cities depended, forcing urban dwellers
- to abandon their empty granaries and silent temples. Refugees
- migrated to southern Mesopotamia (now Iraq), which had escaped
- the disaster. But the unexpected influx of people from the north
- so strained the region's resources that the Akkadian empire
- fell to neighboring hordes.
- </p>
- <p> According to legend, the Mesopotamians blamed their woes on
- Sargon's grandson, whose hubris had supposedly angered the gods.
- But the American and French researchers, led by Yale archaeologist
- Harvey Weiss, offer a more scientific, if no less surprising,
- explanation. They believe the drought was part of a major shift
- in weather patterns that affected the climate in many different
- areas of the globe 4,000 years ago. From Egypt to the Aegean
- to India, rainfall diminished and temperatures dropped. "This
- is opposite to what you might expect from global warming," explains
- George Kukla, senior research scientist at the Lamont-Doherty
- Earth Observatory in New York. "And it was an entirely natural
- change."
- </p>
- <p> By excavating the ancient Akkadian city of Shekhna in what is
- now Syria, Weiss and his colleagues determined that the urban
- center, once a thriving home for 10,000 people, was deserted
- for three centuries. One layer, which they dated to 2200 B.C.,
- revealed the crumbling walls of a ghost town. It also provided
- some important clues about the weather. "Ancient soils bear
- a climatic signature," Weiss explains. "In a dry climate, you
- see very little earthworm activity and lots of loose silt, for
- example."
- </p>
- <p> The pieces of the puzzle started falling into place after Marie-Agnes
- Courty, a geologist with the National Center for Scientific
- Research in Paris, painstakingly examined and sorted the soil
- samples from the roofs of the abandoned buildings under a binocular
- microscope. She identified a thin veil of volcanic ash, one
- quarter of an inch thick, underneath 8 to 20 inches of silt.
- The layers showed no evidence of having been disturbed by earthworms
- and also showed patterns characteristic of soil that has settled
- after a dust storm. It looked like a volcano had erupted, perhaps
- in nearby Turkey, and a long drought had followed.
- </p>
- <p> Wherever the researchers looked throughout the area, they found
- the same story: abandoned buildings and layers of volcanic ash
- and debris from fierce wind storms. After 300 years, when the
- rains returned, so did the people. The telltale scars of scarcity
- eventually were buried under 15 feet of new dirt. A new empire,
- whose capital was Babylon, arose and fell. Today the region
- is flush once again with wheat fields.
- </p>
- <p> Did the volcano cause the ancient drought? "That's unlikely,"
- Weiss says. "Volcanos are not known to generate climatic changes
- of this duration or intensity." So, with one mystery solved,
- researchers find themselves trying to explain how a drought
- can persist for three centuries. At least one thing seems certain.
- The ancient Mesopotamians did not cause the heavens to dry up.
- That raises the ominous possibility that it could happen again.
- And that modern humanity, by dumping pollutants into the atmosphere,
- is tinkering with a climatic system more complex and random
- than humans have realized.
- </p>
-
- </body>
- </article>
- </text>
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