Brutal welcome

The reality of their decision hit before they even unpacked. As Li Hongyan stepped out of the patrol car on her arrival at the border station in Pumaqangtang, her chest tightened in the thin air.

She looked up to see the station instructor, Nyima Gyaltsen, waiting to greet them. He was gaunt, recovering from a recent illness, his hands shaking with exhaustion as he poured them hot tea.

"My initial thoughts were 'This place is truly brutal'," Li said.

The statistics back her up: average temperatures stay below — 7 C, and oxygen levels are less than 40 percent of those at sea level. For the 20 officers and 6 auxiliary staff stationed there, the price of service is physical. Insomnia is constant. Hair falls out in clumps. Memory becomes "fuzzy" as the brain starves for oxygen.

"We joke about going scatterbrained," said Li Tianjiao.

"Whenever we take photos, we have to ask the photographer to airbrush a bit more hair onto our heads. It's a quiet reminder of what we leave behind here."