Climate change poses dangers

Technicians and researchers have long struggled to combat the negative effects of climate change on the permafrost soil that forms the bed of the Qinghai-Tibet Highway, according to the highway authorities in the Tibet autonomous region.

"The rapid thawing of the frozen soil can lead to great instability, causing land slippage and other major problems in areas where major projects such as highways or railways run," said Wu Ziwang, a professor at the Chinese Academy of Science's frozen soil engineering lab.

In the past decade, the autonomous region's Commission for Science and Technology has collaborated with a number of universities and the Chinese Academy of Sciences in an effort to solve the problem. Technical measures such as insulating panels and ventilated embankments have been widely used in key sections of the highway.

Wu Ziwang, a professor at the frozen soil engineering lab of the Chinese Academy of Science, said research he has conducted over three decades indicates that large stretches of permafrost are shrinking because the duration of the "winter freeze" period is becoming shorter and the subsoil is thawing at a faster rate.

According to Zhang Shenghui, director of the Road Maintenance Office of the Tibet Highways Department, there is still no effective method of offsetting the negative effects, so the maintenance workers are required to fill in embankments to bolster the roadbed.