One of the twenty-first century’s greatest — and most controversial — engineering feats in terms of tourism, the Qinghai Railway from Xining in China to Lhasa in Tibet, faces an added threat because of global warming, which may melt the permafrost on which nearly half the 1,956-kilometer railway is built.

The railway, ostensibly built by the Chinese to economically empower the remote, unsettled region, received much criticism when it was opened in July 2006 because of its potential to give China further control over Tibet, the highest region on Earth. Tibetan activists say it increases the immigration of skilled Han Chinese to the ethnically unique region, exploits the region’s vast mineral reserves, and has created greater disparities between the urban rich and rural poor.

Because the permafrost along the route is at a higher temperature than Siberia and the Arctic, its response to climate change will take place earlier than that in other parts of the world. With increased glacial melting swelling lakes, Tibet’s temperatures have climbed an average of 0.32 degrees Celsius every decade since 1961, which is much higher than the Chinese national average temperature rise of 0.05-0.08 degrees, said China Meteorological Administration head Zheng Guoguang, who has instituted dynamic systems to monitor the permafrost’s stability.

“If the warming continues, millions of people in western China would face floods in the short term and drought in the long run. In the worst case, such warming could cause permafrost to melt and threaten the plateau railway linking Tibet with (neighboring) Qinghai province,” Zheng said.

The area is also a known corridor for earthquakes, which could destabilize the permafrost. In addition, though the issue is being addressed, frequent thunderstorms cause chaos with telecommunications and signaling systems.

News agency Xinhua quoted the government as saying that the railway, which added four new passenger trains and more frequent timetables in April and which they hope to extend, would be safe for 40 years if thawing continues at its present speed.

Developers, however, maintain that the railway, which has carried over 10 million passengers, is the most environmentally friendly in the world, and pollution-free energy has been instituted at stations along the Gela Section. Every train is equipped with sewage and garbage collectors, trees and grass have been planted over 4.5 million square meters beside the train, and 15 wastewater treatment centers have been set up.

In addition, government departments say the protection of delicate plateau vegetation is carefully monitored, and 33 special routeways for endangered Tibetan antelope, whose population has increased by 60,000 because of anti-hunting drives, have been built. The burning question is whether it’s all worth it in the long run.