Monitoring the optical turbulence in the surface layer at Dome C, Antarctica, with sonic anemometers

E. Aristidi (1) , J. Vernin (1) , E. Fossat (1) , Schmider F.X. (1) , T. Travouillon (2) , C. Pouzenc (3) , O. Traullé (4) , C. C. Genthon (5) , A. Agabi (1) , E. Bondoux (1) , Z. Challita (6) , D. Mekarnia (1) , F. Jeanneaux (1) , Guillaume Bouchez (7)

1 LAGRANGE - Joseph Louis LAGRANGE
2 Thirty Metre Telescope
3 Observatoire Sirene
4 CNRM - Centre national de recherches météorologiques
5 LGGE - Laboratoire de glaciologie et géophysique de l'environnement
6 LAM - Laboratoire d'Astrophysique de Marseille
7 GEMAC - Groupe d'Etude de la Matière Condensée

The optical turbulence above Dome C in winter is mainly concentrated in the first tens of metres above the ground. Properties of this so-called surface layer (SL) were investigated during the period 2007–2012 by a set of sonic anemometers placed on a 45 m high tower. We present the results of this long-term monitoring of the refractive index structure constant C2n within the SL, and confirm its thickness of 35 m. We give statistics of the contribution of the SL to the seeing and coherence time. We also investigate properties of large-scale structure functions of the temperature and show evidence of a second inertial zone at kilometric spatial scales.

Mots clés: turbulence; atmospheric effects; methods: data analysis; site testing

Domaines: Sciences de l'environnement

E. Aristidi, J. Vernin, E. Fossat, Schmider F.X., T. Travouillon, et al.. Monitoring the optical turbulence in the surface layer at Dome C, Antarctica, with sonic anemometers. Monthly Notices of the Royal Astronomical Society, 2015, 454 (4), pp.4304-4315. ⟨10.1093/mnras/stv2273⟩. ⟨insu-01326462⟩