QINGHAI, Northwest China — When Huang Jianqing and his colleagues head to the market in Gonghe County, Qinghai province, large shopping bags in hand, locals know a shift change is imminent.

“Going up the mountain?” asks a stall owner as he picks out vegetables for Huang, who nods in reply. The vendor knows that before Huang’s team climbs Mt. Waliguan, he always buys enough food to last for 10 days, but he understands little about what they actually do up there.

Atop the mountain, 3,816 meters above sea level on the Qinghai-Tibet plateau, is the China Global Atmosphere Watch Baseline Observatory — the world’s highest center to monitor ozone and greenhouse gases.

There, for the last 28 years, Huang and his team of observers have braved the harsh rocky terrain, bitter cold, and low oxygen conditions, collecting data for the World Meteorological Organization (WMO).

And their work has paid off. The decades of monitoring greenhouse gases, particularly carbon dioxide (CO2), helped develop the “Waliguan Curve.”

Zhou Xiuji, an atmospheric physicist at the Chinese Academy of Sciences who was involved in selecting Waliguan as a monitoring site almost three decades ago, told The Paper: “The Waliguan curve is the result of the work of multiple generations of observers.”

“When the curve flattens out, it means CO2 emissions have peaked and are no longer increasing. When the curve starts to decline, that means we’ve reached carbon neutrality, and that the work to achieve the goal of controlling carbon has been effective.”

The observatory is one of the WMO’s 31 global atmosphere background observatories and the only land-based one in continental Asia. Zhou says the data collected at Waliguan helps support the United Nations Framework Convention on Climate Change, providing reliable foundation materials for studying global and regional changes to the climate and environment, as well as global greenhouse gas reports.

Hill station

Mt. Waliguan lies more than 100 kilometers southwest of the city of Xining in the northwestern Qinghai province.

Looking south from atop the mountain is the Longyang Gorge Hydropower Station, the first dam in the upper reaches of the Yellow River, while the Qinghai Lake is visible to the north.

Click here to see a 360° video of the observatory.

Before this station was given the green light, Zhou recalls that local atmosphere watch stations in China were established in the early 1980s. Then, regional background stations were set up in Lin’an (Zhejiang province), Shangdianzi (Beijing), and Longfengshan (Heilongjiang province).

But these local stations weren’t sufficient. From an international perspective, the WMO Global Atmosphere Watch program had just been integrated at the time, and the First Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) — which red flagged global warming — was about to be released.

With the world waking up to rising greenhouse gas concentrations, atmospheric background baseline watch stations were set up at the north and south poles, but continental Asia had a lacuna — a distinct lack of baseline observations.

According to Zhou, at the time, all the world’s atmospheric background monitoring stations were built at sea or on the coast. There were very few located inland, he says, especially in Asia, where there was no data.

The data gap was bridged when the Mt. Waliguan observatory was established on Sep. 17, 1994. “Scientists around the world wanted to know about CO2 concentrations in continental Asia. Since Asia primarily comprises developing countries, some scientists posited that the concentration would be relatively high,” says Zhou.

“Yet, I saw things differently. Carbon dioxide is an inert gas and so doesn’t react chemically in the atmosphere after it is released. In terms of the global background, it should mix fully, meaning there wouldn’t be much difference globally.”

At the 10th World Meteorological Congress in 1987, Zou Jingmeng, then-director of the China Meteorological Administration, was elected president of the WMO. He believed that as a country with significant global influence, China should take responsibility to establish an atmospheric background station in Asia.

The idea found immediate support.

With no precedent to follow, Zhou and his colleagues first took various instruments to the Qinghai-Tibet plateau for a period of observation before beginning the construction of the observatory. In September 1991, Zhou, then the president of the Chinese Academy of Meteorological Sciences, climbed Mt. Waliguan to inspect the site.

Zhou says Mt. Waliguan was chosen since background stations cannot be built in completely uninhabited areas. Without the conditions necessary for living, it isn’t possible to guarantee continuous observations, he says.

Bumpy start

Zhao Yucheng, who retired this April, was the first head of the observatory’s operations department.

Recalling the time the station was first established, he says countries like Canada, the U.S., and Australia provided the equipment required to make observations, take standardized samples, and ensure international methods for making comparisons. Experts in the field also traveled to Mt. Waliguan from other countries to train the observatory staff in using the various instruments.

When the station was being set up, a certain level of English proficiency was required for all personnel. Since Zhao wasn’t fluent in English at the time, he was sent to the Nanjing Institute of Meteorology to study the language for one year.

After completing the course, he was then sent to Canada to study installation, operation, and maintenance of aerosol chemical sampling equipment for five months at the country’s environmental protection department before returning to start the sampling work at Mt. Waliguan.

Zhao still remembers the station in its infancy. “During the station’s construction and demonstration stages, we had to manually measure the temperature, air pressure, and other meteorological elements. The paper in the recorder needed to be replaced every week,” he says.

“While changing the recorder’s paper on a particularly windy day atop the mountain, I didn’t secure the clip fully and it blew away. I thought I’d messed up and that a week’s worth of observations would be lost. So I pressed a new roll of paper into the box as quickly as I could, and ran after the lost piece of paper. Fortunately, I found it a few hundred meters away.”

Those days, observers worked 10-day shifts atop the mountain, travelling seven-km on a winding, bumpy road. When it snowed, or when the snow melted in spring, the cars often made it only halfway up forcing the scientists to walk the rest of the way, hauling 10 days of supplies on their backs.

After handing the supplies over, the staff coming off a shift would carry the collected samples to the car, and slowly drive down the mountain — in reverse.

“That used to happen at least five or six times a year,” says Zhao. “It can still happen though the road has been fixed.”

Ground zero

Even now, the staff on duty on top of the mountain have to get up early to prepare for the day’s work.

The day after the shift change, Huang Jianqing arrived at the observation site at 7:45 a.m., notebook in hand. He first recorded the clouds, then registered the instrument parameters at the test site and checked the pressure in the air cylinders, before returning to the lab to check the greenhouse gas analyzer, gas chromatograph, and other equipment.

The mountaintop lab has the most advanced instruments in China to monitor greenhouse gases. Each instrument uses different methods to measure the gases; Huang goes back and forth between them to check the parameters.

“If you don’t check every day, you don’t know if there’s been a mistake or not,” says Huang. Pointing to an instrument called the Brewer ozone spectrophotometer, he says: “This is the first of its kind in China. Its serial code is #054, which means it is the 54th in the world. In June 1991, I went to Beijing specifically to learn how to operate it.”

For more expertise, Huang was sent to Antarctica in 1995, which made him the first team member from the observatory to take part in a research expedition to the south pole.

Huang isn’t a talkative man. He says it’s because he’s spent so much time working atop the mountain. For long spells, only two people work at the lab at any given time, each busy with their own work. For a couple of days after going on duty, they chit chat for a bit, but have little to talk about after.

Liu Peng, deputy director of the observatory, has been at Waliguan for 14 years. He says that though Huang never studied electric circuits, he’s capable of fixing most electrical problems.

Huang is also the observatory’s resident expert in high-pressure gas distribution. Currently, only Waliguan and Beijing’s regional station in Shangdianzi have the means to provide high-pressure gas distribution — a vital step in monitoring greenhouse gases. The job is very hands-on: He has to roll the cylinders into place, adjust the pressure, and hook up the gas. Connecting several gas cylinders takes time.

Liu started working at the observatory on March 6, 2001, initially studying surface observation under Zhao Yucheng and Huang Jianqing for one month. The first time he went up the mountain, he recalls, he was so engrossed in the lab’s advanced instruments that he forgot about the harsh surroundings.

Zhao reminded him that atop the mountain, he had to learn how to cook since there was no one else up there; it was every man for himself.

Referring to the first generation of meteorological observers, like Huang and Zhao, Liu says, “They were very rigorous in their work. For example, when it is time to record the measurements, they do it exactly to the minute, never early or late. Another example is that they record everything they do in their notebooks, rather than just relying on memory.”

“As the next generation of atmospheric background observers, we must carry on their rigorous spirit and good habits. Many years later, sometimes when an instrument isn’t working, I’ll start flicking through my notebook and suddenly remember. These habits are extremely valuable,” says Liu.

High point

The mountaintop lab may be the perfect location to measure concentrations of greenhouse gases, but it presents multiple challenges for human habitation.

When he was young, Zhao Yucheng was in good shape — he even caught hares running on the mountain. Now 45, he’s started to suffer from altitude sickness and insomnia.

He recalls changing the direction his bed faced every time he couldn’t sleep while on the mountain. Two years ago, he stopped going up altogether, complaining of frequent headaches and his fingernails turning blue — unmistakable signs of oxygen deprivation.

Huang Jianqing is also close to retiring. He too struggles with insomnia when on duty. When he does manage to sleep, he’s often jolted awake by nightmares of the observatory’s instruments suddenly malfunctioning.

On the mountain, the observers seem to repeat the same monotonous tasks day after day. But over the years, they’ve seen data from Waliguan used in reports by organizations such as the IPCC, and feel that they’ve spent their lives doing something meaningful for the country.

“The main significance of the observatory is to provide continuous and high-quality monitoring data,” Liu says. “If it’s not accurate and continuous, it will lead to misunderstandings in subsequent climate change research and affect the judgments of decision-makers.”

According to Zhou Xiuji from the Chinese Academy of Sciences, the Waliguan curve is consistent with trends observed in Hawaii and is a highly successful observation. “It represents the global background data and has become an important support for the WMO in studying climate change. It is also extremely important when it comes to assessing global CO2 targets,” he says.

“The data has been strictly compared internationally, and experts from the WMO hold the measurements recorded here in high regard. The Waliguan curve has played a huge role in all aspects of our country’s climate diplomacy.”

A version of this article was originally published by The Paper. It has been translated and edited for length and clarity, and is reproduced here with permission.

Translator: David Ball; editors: Xue Yongle and Apurva.

(Header image: A general view of the China Global Atmosphere Watch Baseline Observatory, Qinghai province, 2021. Shi Hanwei for Sixth Tone)