Giordano, C., J. Vernin, UniversitŽ de Nice-Sophia
Antipolis, Observatoire de la C™te dÕAzur, CNRS-UMR7293, Lab. Lagrange,
France. A. Mahalov & M.
Moustaoui, Center for Environmental Fluid Dynamics, Arizona State University
We propose to present
the first results obtained with WRF model in an astronomical context. The
purpose of our study is to predict 24 hours ahead the optical conditions above
an observatory to optimize the observation time, not only the meteorological
conditions at ground level, but also the vertical distribution of the Òoptical
turbulenceÓ and the wind speed, i.e the ÒseeingÓ. We chose to test the WRF
model above Dome C, in Antarctica, where the astronomical conditions are very
particular. Indeed during the summer, we can observe a steep and sudden
improvement of the seeing when the sun is culminating above the horizon. It is
interesting to test WRF above this site in order to retrieve this decrease. The
seeing is computed using the Trinquet-Vernin model coupled with the vertical
profiles of the wind shear and the potential temperature predicted by the WRF
model. WRF is parametrized with its finest grid of 1km and 99 vertical levels
with the vertical nesting. WRF first comparison with in situ seeing
measurements made with a Differential Image Motion Monitor are very promising.