We present some statistics of turbulence monitoring at the Plateau de Calern (France), with the Generalised Differential Image Motion Monitor (GDIMM). This instrument allows to measure integrated parameters of the atmospheric turbulence, i.e. seeing, isoplanatic angle, coherence time and outer scale, with 2 minutes time resolution. It is running routinely since November 2015 and is now fully automatic. A large dataset has been collected, leading to the first statistics of turbulence above the Plateau de Calern.
From its long expertise in Atmospheric Optics, the J.L. Lagrange Laboratory of the Observatoire de la Côte d'Azur has developed a new generation of autonomous stations of atmospheric turbulence measurement. Since two years, the Calern Observatory is equipped with this kind of stations called CATS for Calern Atmospheric Turbulence Station. CATS is an autonomous station consisting of a set of complementary instruments within original techniques for measuring optical turbulence since the first meters above the ground to the borders of the atmosphere including the dome seeing. Indeed, one of the CATS instruments is the PML (Profiler of Moon Limb) measuring the vertical distribution of turbulence using lunar and solar limbs with a resolution reaching 100m in the ground layer. The second instrument is a Generalized DIMM dedicated to provide wavefront parameters at ground level (seeing, outer scale, coherence time and isoplanatic angle). A third instrument called INTENSE (INdoor TurbulENce Sensor) is occasionally associated with CATS station to measure the turbulence inside the dome of the 1.5m MeO telescope to evaluate its contribution to the whole turbulence. The CATS station is also a support for our educative activities as part of our Masters in Astronomy and Optics, through the organization of on-sky training works.
Optical systems performances can be affected by local optical turbulence created by its surrounding environment (telescope dome, clean room, atmospheric surface layer). We present recent measurements of the local turbulence inside the 1.5m M´eO telescope dome at Calern observatory (France) with the INTENSE (INdoor TurbulENce SEnsor) instrument. Relationships between the dome turbulence and the local meteorological measurements (temperature, pressure, wind speed and direction) are investigated. The impact of the local dome turbulence on the seeing at the focal plane of the 1.5 m telescope is highlighted.