  We present very encouraging preliminary results obtained in the context of
the MOSE project, an on-going study aiming at investigating the feasibility of
the forecast of the optical turbulence and meteorological parameters (in the
free atmosphere as well as in the boundary and surface layer) at Cerro Paranal
(site of the Very Large Telescope - VLT) and Cerro Armazones (site of the
European Extremely Large Telescope - E-ELT), both in Chile. The study employs
the Meso-Nh atmospheric mesoscale model and aims at supplying a tool for
optical turbulence forecasts to support the scheduling of the scientific
programs and the use of AO facilities at the VLT and the E-ELT. In this study
we take advantage of the huge amount of measurements performed so far at
Paranal and Armazones by ESO and the TMT consortium in the context of the site
selection for the E-ELT and the TMT to constraint/validate the model. A
detailed analysis of the model performances in reproducing the atmospheric
parameters (T, V, p, H, ...) near the ground as well as in the free atmosphere,
is critical and fundamental because the optical turbulence depends on most of
these parameters. This approach permits us to provide an exhaustive and
complete analysis of the model performances and to better define the model
operational application. This also helps us to identify the sources of
discrepancies with optical turbulence measurements (when they appear) and to
discriminate between different origins of the problem: model parameterization,
initial conditions, ... Preliminary results indicate a great accuracy of the
model in reproducing most of the main meteorological parameters in statistical
terms as well as in each individual night in the free atmosphere and in
proximity of the surface. The study is co-funded by ESO and INAF-Arcetri
(Italy).
