CRI听力:Scientific Expedition in Lop Nor

Lop Nor, also known as the "ear of the world," is a dried-up salt lake in the arid basin of the Tarim River in northwest China. A group of researchers recently conducted the largest scientific expedition there in 30 years. They found that Lop Nor, also known as Luo Bu Po in Chinese, was not only much larger than previously estimated, but also the driest area of China. Wu Jia has more.



A group of 75 scientists took part in the one-month expedition which covered a distance of 6,500 kilometers.

One of the key findings indicated that the size of the lake basin was twice as large as originally estimated.

Satellite images show that the lake basin is shaped just like a human's ear. Before the expedition, which ended earlier this month, the basin was believed to have covered an area of only some 5,000 square kilometers.

But as explorers discovered signs of the northwestern lakeshore, they proved that the big ear only occupied half of the entire lake basin.
The basin is actually a round enclosure covering 10,000 square kilometers.

Xia Xuncheng, Chief Scientist at the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences, was head of the expedition team.

He says 40,000 years ago, the lake was five times as big as it is now.

"We once studied the local environmental changes 10,000 years ago, but this time we found that more than 40,000 years ago the Yadan Landform was also part of Lop Nor. The lake then covered 50,000 square kilometers and contained water not only from Tarim River but also from the Qilian Mountains in Gansu Province."

In 1959, Lop Nor still had a huge area covered by water. Yet, because of severe drought the water soon evaporated, and the water level dropped a meter each year without rainwater to replenish it. Three years later the lake dried up.

Zhao Yong, a researcher at the Urumqi Institute of Desert Meteorology, says there is hardly any rain at any time of the year, while the annual evaporation rate is about 3,000 to 4,000 millimeters. The relative humidity of the air at the basin is zero.

"By comparison, Taklamakan Desert has an annual precipitation of 28 millimeters, while the precipitation in Lop Nor is 13.6 (millimeters). That is to say, the driest area in the Tarim Basin is not at the center of the basin but in Lop Nor, the easternmost end."

As the expedition progressed, scientists also found indications of agricultural activity, including many irrigation channels and farmlands, 10 kilometers east of ancient Loulan city.

The expedition was also held in memory of the great scientist, Peng Jiamu, who set off to explore Lop Nor in 1980 and disappeared.

For CRI, I'm Wu Jia.