The meteorological data recorded at Waliguan has never stopped and has never been interrupted. "The observational data from nearly 30 years are a valuable asset to China's meteorological endeavors," Hu said.

In the late 1980s, then director of the National Meteorological Administration and World Meteorological Organization president Zou Jingmeng said that China must establish a high-standard, global atmospheric background observatory inland or on a plateau to enhance global monitoring of greenhouse gases and research on climate change.

In Beijing and Geneva on Sept 15, 1994, representatives from the Chinese government and the World Meteorological Organization, said the Waliguan observatory was to become the world's highest observatory for monitoring ozone and greenhouse gases at that time, filling the void in global atmospheric background monitoring in the Eurasian continent's hinterland.

Gregory R. Carmichael, chair of the Scientific Steering Committee of Global Atmosphere Watch, said during the 30th anniversary of the establishment of the Waliguan observatory: "It faced many challenges in construction and in establishing operations. This site joined observatories at Cape Grim, Cape Point, Mauna Loa, Jungfraujoch and Zugspitze, among others to form the backbone of a high-quality global network of background/baseline stations."

To date, the Waliguan observatory has provided the world with continuous data on globally representative atmospheric elements such as carbon dioxide, methane, nitrous oxide and stable isotopes. Particularly noteworthy is the Waliguan Curve's tracking of carbon dioxide variations, one of its most representative achievements.

"The international contributions of the China Meteorological Association and its partner institutions through the operation of Mount Waliguan are truly exemplary. Mount Waliguan and China are key contributors to Global Atmosphere Watch, not only through their GAW sites, but also through their active participation in GAW scientific advisory boards and expert teams," Carmichael said.

The Waliguan Curve shows a yearly increase in atmospheric carbon dioxide concentration, perfectly aligning with observational data from the Mauna Loa Observatory in Hawaii, and serving as a crucial basis for countries worldwide to formulate international climate agreements.