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Kilimanjaro ice cap almost gone
18/10/2002 09:27 - (SA)
Paul Recer
Washington - The snow cap of Mount Kilimanjaro, famed in literature and beloved by tourists, first formed some 11 000 years ago, but will be gone in two decades, according to researchers who say the ice fields on Africa's highest mountain shrank by 80 percent in the past century.
Lonnie G. Thompson of Ohio State University said measurements
using ice corings and modern navigation satellites show that the
oldest ice layers on the famed mountain were deposited during an
extremely wet period starting about 11 700 years ago.
But a temperature rise in recent years, measured at about a full
degree since 2000, is eroding the 50 metre high blocks of ice that gave Kilimanjaro its distinctive white cap.
"The ice will be gone by about 2020," said Thompson, the first
author of a study appearing on Friday in the journal Science. The
diminishing ice already has reduced the amount of water in some
Tanzanian rivers and the government fears that when Kilimanjaro is bald the tourists will stop coming.
"Kilimanjaro is the number one foreign currency earner for the
government of Tanzania," said Thompson. "It has its own
international airport and some 20 000 tourists every year. The
question is how many will come if there are no ice fields on the
mountain."
The mountain is enshrined in literature, most notably Ernest
Hemingway's The Snows of Kilimanjaro and some ancient beliefs in Africa hold the mountain to be a sacred place.
Water from the mountain supplies villages and hospitals and
already some are suffering, said Thompson.
Scientists raced to drill cores from the shrinking ice field
because the frozen layers tell a story of Africa's ancient weather, and, indirectly, give clues about the global climate.
An extremely wet period evidenced in the ice corings matches
independent studies that showed about 11 000 years ago the lakes in Africa spilled across vast areas of the continent.
Lake Chad, for instance, said Thompson, grew until it covered
345 000 square kilometres, about the size of the present day Caspian Sea. The African lake now is only about 17 square kilometres.
That wet period ended and the ice corings show that Africa slid
into a deep drought about 4 000 years ago.
This dry period, said Thompson, is also found in other records,
including some written history.
"This dry period appears in the historic record in Egypt," he
said. "Writings on tombs talk about sand dunes moving across the
Nile and people migrating. Some have called this the Earth's first dark age."
Africa was not alone in the global drought. Thompson said other
records show that civilisations during this period collapsed in
India, the Middle East and South America.
Researchers put markers atop the ice field blocks in 1962 and
Thompson said measurements using satellites show the summit of the ice has been lowered by about 56 feet in 40 years.
The margin of the ice also has retreated more than six feet in
the past two years, he said.
"That's more than two metre's worth of ice lost from a wall 50
metres high," said Thompson. "That's an enormous amount of ice."
On the net:
Science journal - Sapa/AP
- SAPA
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