In early 2006, as the five-year construction project finally neared completion, a Chinese Academy of Sciences (CAS) engineer named Wu Ziwang predicted that the rate of change was more serious, concluding that the frozen ground supporting the railway could be soaked with puddles within a decade. A lone voice at the time, the researcher was admonished for his candor, rebuked by his department, and later declined to be interviewed for this story when I visited his CAS office in Lanzhou, located deep in central China.
Out of danger?
Clearly, not everyone believes the railway is in imminent danger. According to Cheng Guodong, one of the project's master scientists, the permafrost directly under the rail bed may be thinning, but it is holding firm, and that bodes well for its ability to withstand further warming. In his 2006 paper published in the journal Cold Regions Science and Technology, he wrote, "The temperature of the permafrost under the duct…decreased remarkably." As a result of this, according to the paper, the frozen layers have spread upward in some places, freezing the dirt infill of the rail bed itself.
Guodong explains that the construction impact posed a greater threat to the plateau permafrost than global warming. "The first two to three years might be the most dangerous period," he wrote in a translated e-mail in May. "If we had not considered the influencing factors well enough, thermal and stress adjustments would tell us."
If the railway has done well this far, as he says it has, then it will likely withstand whatever stresses the climate throws at it next—at least for awhile.
Abrahm Lustgarten is a reporter at ProPublica and is the author of China's Great Train, Beijing's Drive West and the Campaign to Remake Tibet, which was released in paperback in May.