Meteorological data from KLAWS-2G for an astronomical site survey of Dome A, Antarctica

TL;DR

This study analyzes meteorological data from Dome A, Antarctica, revealing persistent temperature inversions and moderate winds that influence the boundary layer, informing optimal telescope placement and emphasizing the need for long-term data.

Contribution

First detailed analysis of KLAWS-2G meteorological data at Dome A, providing insights into temperature inversions, wind speeds, and boundary layer characteristics for astronomical site assessment.

Findings

Persistent temperature inversions up to 14 m elevation.

Average wind speeds around 4 m/s at 4 m elevation.

Boundary layer is shallow, suggesting telescopes should be elevated at least 8 m.

Abstract

We present an analysis of meteorological data from the second generation of the Kunlun Automated Weather Station (KLAWS-2G) at Dome A, Antarctica during 2015 and 2016. We find that a strong temperature inversion exists for all the elevations up to 14 m that KLAWS-2G can reach, and lasts for more than 10 hours for 50% or more of the time when temperature inversion occurs. The average wind speeds at 4 m elevation are 4.2 m/s and 3.8 m/s during 2015 and 2016, respectively. The strong temperature inversion and moderate wind speed lead to a shallow turbulent boundary layer height at Dome A. By analyzing the temperature and wind shear profiles, we note telescopes should be elevated by at least 8 m above the ice. We also find that the duration of temperature inversions, and the wind speed, vary considerably from year to year. Therefore, long-term and continuous data are still needed for the site survey at Dome A.