At 4,534 meters above sea level, they help monitor world climate change

XINING -- In the early morning, Shi Kaihao struggles to run against the wind. The sharp breeze cuts through his clothes, but he is focused on his task: dragging a two-meter-diameter hydrogen balloon to the sky.

Twice a day, with the help of his colleagues, he fills the balloon with hydrogen, hangs sensors that measure temperature, humidity, wind speed and other meteorological data at the bottom of the balloon, and releases it into the air.

Shi, 28, works at the Tuotuohe Meteorological Station at an altitude of 4,534 meters, located at the source of the Yangtze River in the city of Golmud, Northwest China's Qinghai province.

Since its establishment in 1956, meteorologists have been stationed there, obtaining precious meteorological data and contributing to the climate observation on the Qinghai-Tibet Plateau, known as "the roof of the world."

Releasing balloons in this high-altitude area is no easy feat, considering the oxygen content in the air is less than 60 percent of that at sea level and the maximum wind speed reaches 17 meters per second. Even in spring, temperatures remain far below freezing, and the thin air makes every movement exhausting.

"Sometimes, some of our slighter colleagues get dragged by the wind while running to release the balloon, ending up thrown hard to the ground," said Shi.

In addition to upper-air meteorological observations, he and his colleagues carry out fieldwork including permafrost monitoring, temperature measurements and ecological surveys.

Miao Peilin, head of the station, said the upper-air detection measurements contribute to global meteorological data exchange, providing a vital reference for studying worldwide weather patterns and climate change on the Qinghai-Tibet Plateau.

"Despite various hardships, we know that our meteorological observation data is of great significance," said Miao, 36.

The station now has nine workers. Miao not only works with the team on daily weather monitoring tasks but also takes care of his colleagues, aged between 25 and 30. He said many young people struggle to adapt here, spending years in solitude.

"After working here for a while, even traffic in the city feels scary," he said.

The station keeps a cat and this lively little companion brings joy to their otherwise quiet and routine-filled days.

Over the decades, the station has witnessed enormous changes. Wang Shengcang, the observation center director of Golmud's meteorological bureau, used to work in the station for 12 years, starting in 1993. Back then, before the railway line had been built, he and his colleagues had to hitch a lift on trucks to get to the station from the city proper. The trip took up to two days if it was snowy. Supplies were scarce, often little more than potatoes and cabbage.

"A monthly letter from home became my meager comfort," said Wang, now 54.

The working conditions there have greatly improved, with makeshift facilities transformed into brick-and-mortar houses and dormitories with an oxygen supply.

Equipment upgrades have also enhanced meteorological data automation and accuracy. In 2023, the new BeiDou satellite-based navigation sounding system became operational, enabling real-time acquisition of second-level atmospheric data during the ascent, float and descent stages of weather balloons. This significantly enhances vertical atmospheric sounding capabilities and greatly improves meteorological support for disaster prevention and mitigation.

Data from the Tuotuohe Meteorological Station shows that over the past 30 years, the average annual temperature in the area has risen by 1.1 degrees Celsius, annual precipitation has increased by 13.8 percent, and the number of sandstorm days has decreased from an average of 11.1 days per year to 5 days compared with the 1971-2000 period.

Zhang Chengxiang, head of Golmud's meteorological bureau, said that rising temperatures and increased precipitation confirmed the warming and humidification trend of the Qinghai-Tibet Plateau. At the same time, the decrease in sandstorms and strong winds is attributed to ecological conservation efforts such as desert control and grassland restoration in nearby regions like the Sanjiangyuan, an area that contains the headwaters of the Yangtze, Yellow and Lancang rivers.

"The data serves as strong evidence of climate change on the Qinghai-Tibet Plateau and provides important references for permafrost research and ecological management on the plateau," he said.