Jimu-1, a helium-filled tethered balloon, was launched on May 23 and will reach a record altitude of 7,003 meters. [Image from China Daily]

Chinese scientists launched Jimu-1, a giant aerostat or helium-filled tethered balloon, on May 23 morning to observe atmospheric water vapor at a record altitude of 7,003 meters in the Nam Co region of the Qinghai-Tibet Plateau.

Unlike a blimp, which is powered and steerable in the air, Jimu-1 is essentially a super-sized balloon with a volume of 2,300 cubic meters. It is made of a composite fabric that can withstand temperatures as low as - 70℃. It is the first time an aerostat of its class and weight has operated at such an altitude.

Jimu-1 is the first of three Chinese made aerostats that will be tasked with collecting more accurate atmospheric data to be used in studying climate change and sustainable development in the region, according to the Aerospace Information Research Institute of the Chinese Academy of Sciences, the balloon's manufacturer and operator.

Jimu-2, which is expected to be completed next year, will operate at an altitude of around 7,000 to 7,500 meters, said Li Zhaojie, director of the academy's Center for Lighter than Air System Research and Development.

Jimu-3, scheduled to be finished in 2021, will be a "state-of-the-art model" that will reach an altitude of more than 8,848 meters, greater than that of Mount Qomolangma, he said, adding this will be a monumental feat that will push the limits of engineering given its technical difficulties and scientific value.

Gao Jing, a professor at the academy's Institute of Tibetan Plateau Research, said ground-based instruments are generally used to observe atmospheric data such as water vapor, methane and dust, but they are too far away to examine moisture transport and environmental changes at high-altitude, or to assess their impact on human activities.

"But with Jimu, we can carry all sorts of instruments to various heights and collect data directly," she said. "This gives scientists a brand-new view of atmospheric moisture transportation processes and regional climate change."

The aerostat's size and design allows it to carry a heavier payload and have a greater resistance to the elements than a typical weather balloon, Li said. "This resistance is critical for the balloon's application since the weather conditions and the electromagnetic environment on the plateau can be very harsh and complex."

The Qinghai-Tibet Plateau is dubbed the "third pole". It is the source of many Asian rivers, including the Yangtze, Yellow, Indus and Mekong, as well as the natural habitat of rare animals, including Tibetan antelopes, wild yaks and black-necked cranes.

However, the effects of climate change are threatening the plateau's fragile ecosystem, which can have a profound impact on the region and the world. "This monitoring will allow us to have a better understanding of the water cycle and its influence on the ecosystem," Gao said.

Source: China Daily