2017/07/26 by Chao-Lin Kuo
Earth and Planetary Sciences · Engineering · Environmental Science · Physics and Astronomy · #Brightness temperature #Dome (geology) #Northern Hemisphere #Precipitation Measurement and Analysis #Radio Wave Propagation Studies #Satellite #Sky #Soil Moisture and Remote Sensing #Southern Hemisphere #Summit #astro-ph.CO #astro-ph.IM
paper · pdf · doi:10.3847/1538-4357/aa8b74
14 pages, 8 figures
arxiv created 2017/07/26 · openalex created_date 2017/07/31 · openalex publication_date 2017/10/10 · arxiv updated 2017/10/18 · openalex updated_date 2026/08/05
Abstract NASA’s latest MERRA-2 reanalysis of the modern satellite measurements has made atmospheric data easily accessible with unprecedented uniformity, fidelity, and completeness. In this paper, these data are used to evaluate five sites for millimeter-wave (mm-wave) observations. These include two established sites (South Pole and Chajnantor, Atacama), and three new sites (Ali in Tibet, Dome A in Antarctica, and Summit Camp in Greenland). Atmospheric properties including precipitable water vapor (PWV), sky brightness temperature fluctuations, and ice and liquid water paths are derived and compared. Dome A emerges to be the best among those evaluated, with PWV and fluctuations smaller than the second-best site, South Pole, by more than a factor of 2. It is found that the higher site in Ali (6100 m) is on par with Cerro Chajnantor (5612 m) in terms of transmission and stability. The lower site in Ali (5250 m) planned for the first stage of observations at 90/150 GHz provides conditions comparable to those on the Chajnantor Plateau. These analyses confirm Ali to be an excellent mm-wave site in the Northern Hemisphere that will complement well-established Southern sites. According to MERRA-2 data, the observing conditions at Summit Camp are also comparable to Cerro Chajnantor. However, it is more affected by the presence of liquid water clouds.