September 28, 2021 marks the fourth year of establishment of "Atmospheric Profiling Synthetic Observation System" (APSOS) in Yangbajain, about 90 kilometers from Lhasa and 4300 meters above the sea level.
APSOS is the world's first ground-based facility for profiling atmospheric variables and multiple constituents in the whole (neutral) atmosphere, covering the altitudes of the troposphere, stratosphere, mesosphere, and the lower thermosphere.
The APSOS site selection team led by CAS Academician LYU Daren (middle) and the head of the APSOS observatory WANG Yinan (first from left). Photo was taken in the spring of 2017. (Image by IAP）
The site selection team stood around a pile of yak's manure on April 1, 2017. It's where APSOS was built from the scratch. (Image by IAP)
After the main building of APSOS was complete in September 2017, facilities were transported by trucks from Huainan, Anhui Province, where they were trialed before being installed in Yangbajing. (Image by IAP)
A crane was hoisting and installing telescopes in September 2017. APSOS was officially launched on September 28, 2017 and it soon started probing the whole atmosphere. (Image by IAP)
A scientist observed the status of the laser in July 2019. (Image by IAP)
[video:羊八井]
Panorama view of APSOS in 2019.(video taken by an IAP drone)
Mesosphere-Stratosphere-Troposphere (MST) radar experiment facility built in 2020 on the campus of APSOS station. (Image by IAP)
A joint observation field on the campus of APSOS station was completed in 2021. It includes an automatic weather station, an all-sky and infrared imager, a surface radiometer, a microwave radiometer, and off-line sampling instruments for pollutant gases and particulates. New instruments will be installed as APSOS develops. (Image by IAP)
Probing the whole atmosphere for four years on the Tibetan Plateau, APSOS provides valuable observations for researches on middle atmospheric dynamics, radiative fluxes, cloud properties, and surface variables, including albedo and pollutants. Recently, the APSOS observatory became the "base camp" for the Meridian Project Phase Ⅱ, and in the near future, a MST radar, an all-day-operational lidar, and a millimeter-infrared active and passive imager will be added to the station.
Media contact: Ms. LIN Zheng, jennylin@mail.iap.ac.cn
